CHRONOSPHERE » Perfusion http://chronopause.com A revolution in time. Fri, 03 Aug 2012 22:34:48 +0000 en-US hourly 1 http://wordpress.org/?v=3.5.1 THE EFFECTS OF CRYOPRESERVATION ON THE CAT, Part 1 http://chronopause.com/index.php/2012/02/13/the-effects-of-cryopreservation-on-the-cat-part-1/ http://chronopause.com/index.php/2012/02/13/the-effects-of-cryopreservation-on-the-cat-part-1/#comments Mon, 13 Feb 2012 22:46:34 +0000 chronopause http://chronopause.com/?p=1309 Continue reading ]]> by Michael Darwin, Jerry Leaf, Hugh L. Hixon

I.    Introduction                                  

II.   Materials and Methods

III   Effects of Glycerolization

IV.  Gross Effects of Cooling to and Rewarming From -196°C

I. INTRODUCTION

The  immediate  goal  of human cryopreservation  is  to  use  current cryobiological  techniques  to  preserve the  brain  structures  which encode personal identity adequately enough to allow for  resuscitation or reconstruction of the individual should molecular nanotechnology be realized (1,2).  Aside from two previous isolated efforts (3,4)  there has  been  virtually no systematic effort to examine the  fidelity  of histological,  ultrastructural, or even gross structural  preservation of  the brain following cryopreservation in either an animal or  human model.    While  there  is  a  substantial  amount  of  indirect   and fragmentary  evidence  in the  cryobiological  literature  documenting varying  degrees  of  structural  preservation  in  a  wide  range  of mammalian tissues (5,6,7), there is little data of direct relevance to cryonics.   In particular, the focus of contemporary  cryobiology  has been   on   developing  cryopreservation  techniques   for   currently transplantable  organs,  and this has necessarily  excluded  extensive cryobiological  investigation  of  the brain, the  organ  of  critical importance to human identity and mentation.

The  principal  objective of this pilot study was to  survey  the effects of glycerolization, freezing to liquid nitrogen  temperature, and  rewarming  on  the physiology, gross  structure,  histology,  and ultrastructure of both the ischemic and non-ischemic adult cats  using a preparation protocol similar to the one then in use on human cryopreservation patients.  The non-ischemic group was given the designation Feline Glycerol Perfusion (FGP) and the ischemic group was referred to as Feline Ischemic Glycerol Perfusion (FIGP).

The work described in this paper was carried out over a  19-month period from January, 1982 through July, 1983.  The perfusate  employed in this study was one which was being used in human cryopreservation operations at that time, the composition of which is given in Table I.

The principal cryoprotectant was glycerol.

II. MATERIALS AND METHODS

Pre-perfusion Procedures

Nine adult cats weighing between 3.4 and 6.0 kg were used in this study.  The animals were divided evenly into a non-ischemic and a  24-hour mixed warm/cold ischemic group.  All animals received humane care in  compliance  with  the  “Principles  of  Laboratory  Animal   Care” formulated by the National Society for Medical Research and the “Guide for  the Care and Use of Laboratory Animals” prepared by the  National Institutes  of  Health  (NIH Publication  No.  80-23,  revised  1978).  Anesthesia   in  both  groups  was  secured  by  the   intraperitoneal administration of 40 mg/kg of sodium pentobarbital.  The animals  were then  intubated and placed on a pressure-cycled ventilator.   The  EKG was monitored throughout the procedure until cardiac arrest  occurred. Rectal and esophageal temperatures were continuously monitored  during perfusion using YSI type 401 thermistor probes.

Following placement of temperature probes, an IV was  established in  the medial foreleg vein and a drip of Lactated Ringer’s was  begun to  maintain  the  patency of the IV and  support  circulating  volume during  surgery. Premedication (prior to perfusion) consisted of  the IV  administration of 1 mg/kg of metubine iodide to inhibit  shivering during  external  and  extracorporeal cooling  and  420  IU/kg  sodium heparin  as  an anticoagulant.  Two 0.77 mm I.D.  Argyle  Medicut  15″ Sentinel line catheters with Pharmaseal K-69 stopcocks attached to the luer fittings of the catheters were placed in the right femoral artery and vein.  The catheters were connected to Gould Model P23Db  pressure transducers   and  arterial  and  venous  pressures   were   monitored throughout the course of perfusion.

Surgical Protocol

Following placement of the monitoring catheters, the animals were transferred  to a tub of crushed ice and positioned for surgery.   The chest  was shaved and a median sternotomy was performed.   The  aortic root was cleared of fat and a purse-string suture was placed,  through which  a  14-gauge  Angiocath was introduced.   The  Angiocath,  which served  as  the  arterial  perfusion cannula,  was  snared  in  place, connected  to  the  extracorporeal circuit and cleared  of  air.   The pericardium  was  opened  and tented to expose the  right  atrium.   A purse-string  suture was placed in the apex of the right atrium and  a USCI  type  1967 16 fr. venous cannula was introduced  and  snared  in place.  Back-ties were used on both the arterial and venous cannulae to secure  them and prevent accidental dislodgment during the  course  of perfusion.  Placement of cannulae is shown in Figure 1.

Figure 1: Vascular access for extracorporeal perfusion was via median sternotomy. The arterial cannula consisted of a 14-gauge  Angiocath (AC) which was placed in the aortic root (AR) and secured in place with a purse string suture. A USCI  type  1967 16 fr. venous cannula (VC) was placed in the right atrium (RA) and snared in place using 0-silk ligature and a length of Red Robinson urinary catheter (snare). The chest wound was kept open using a Weitlander retractor. The left ventricle (LV) was not vented.

  Extracorporeal Circuit

Figure 2: Cryoprotective perfusion apparatus: RR = recirculating reservoir, PMC = arterial pressure monitor and controller, MBD = micro-bubble detector, US = ultrasonic sensor, ADC = arterial drip chamber, D/0 = dialyzer/oxygenator, RP = cryoprotective ramp pump, HEX = arterial heat exchanger, 40 MFH = 40 micron filter holder, PT = arterial pressure transducer, CR = glycerol concentrate reservoir, EKG = electrocardiograph, TT = thermistor thermometer, TS = thermistor switch box, IB = ice bath, EC = electrocautery, APD = arterial pressure display.

The extracorporeal circuit (Figures 2&3) was of composed of 1/4″ and 3/8″  medical grade polyvinyl chloride tubing.  The circuit  consisted of  two  sections:  a  recirculating loop  to  which  the  animal  was connected  and a glycerol addition system.  The  recirculating  system consisted  of  a  10 liter polyethylene reservoir  positioned  atop  a magnetic  stirrer, an arterial (recirculating) roller pump,  an  Erika HPF-200  hemodialyzer which was used as a hollow fiber oxygenator  (8) (or alternatively, a Sci-Med Kolobow membrane oxygenator), a  Travenol Miniprime  pediatric  heat  exchanger, and a 40-micron  Pall  LP  1440 pediatric blood filter.  The recirculating reservoir was  continuously stirred with a 2″ Teflon-coated magnetic stir bar driven by a  Corning PC  353 magnetic stirrer.  Temperature was continuously  monitored  in the  arterial line approximately 15.2 cm from the arterial  cannula using a Sarns in-line thermistor temperature probe and YSI 42SL remote sensing  thermometer.  Glycerol concentrate was continuously added  to the recirculating system using a Drake-Willock dual raceway hemodialysis pump, while venous perfusate was concurrently withdrawn from the circuit and discarded using a second raceway in the same pump head.

Figure 3: Schematic of cryoprotective perfusion circuit.

Storage and Reuse of the Extracorporeal Circuit

After  use the circuit was flushed extensively with filtered  tap and distilled water, and then flushed and filled with 3%  formaldehyde in distilled water to prevent bacterial overgrowth.  Prior to use  the circuit was again thoroughly flushed with filtered tap water, and then with  filtered distilled water (including both blood and gas sides  of the hollow fiber dialyzer; Kolobow oxygenators were not re-used).   At the  end  of  the distilled water flush, a test for  the  presence  of residual formaldehyde was performed using Schiff’s Reagent.  Prior  to loading  of  the perfusate, the circuit was rinsed with 10  liters  of clinical  grade normal saline to remove any particulates  and  prevent osmotic dilution of the base perfusate.

Pall filters and arterial cannula were not re-used.  The  circuit was replaced after a maximum of three uses.

Preparation of Control Animals

Fixative Perfusion

Two control animals were prepared as per the above.  However, the animals  were subjected to fixation after induction of anesthesia  and placement  of cannulae.  Fixation was achieved by first perfusing  the animals   with  500  mL  of  bicarbonate-buffered  Lactated   Ringer’s containing 50 g/l hydroxyethyl starch (HES) with an average  molecular weight  of  400,000 to 500,000 supplied by  McGaw  Pharmaceuticals  of Irvine, Ca (pH adjusted to 7.4) to displace blood and facilitate  good distribution of fixative, followed immediately by perfusion of 1 liter of  modified  Karnovsky’s  fixative (Composition given  in  Table  I).  Buffered Ringers-HES perfusate and Karnovsky’s solution were  filtered through 0.2 micron filters and delivered with the same  extracorporeal circuit described above.

Immediately   following  fixative  perfusion  the  animals   were dissected and 4-5 mm thick coronal sections of organs were cut, placed in  glass screw-cap bottles, and transported, as detailed  below,  for light or electron microscopy.

Straight Frozen Non-ischemic Control

One animal was subjected to straight freezing (i.e., not  treated with   cryoprotectant).    Following  induction  of   anesthesia   and intubation  the  animal  was supported on  a  ventilator  while  being externally  cooled  in  a  crushed  ice-water  bath.   When  the   EKG documented  profound bradycardia at 26°C, the animal was  disconnected from  the  ventilator,  placed  in a  plastic  bag,  submerged  in  an isopropanol  cooling bath at -10°C, and chilled to dry ice and  liquid nitrogen  temperature  per the same protocol used for  the  other  two experimental groups as described below.

Preparation of FGP Animals

Following  placement of cannulae, FGP animals were  subjected  to total  body  washout  (TBW) by open-circuit perfusion  of  500  mL  of glycerol-free  perfusate.  The extracorporeal circuit was then  closed and constant-rate addition of glycerol-containing perfusate was begun.

Cryoprotective  perfusion continued until the target concentration  of glycerol  was reached or the supply of glycerol-concentrate  perfusate was exhausted.

Preparation of FIGP Animals

In   the  FIGP  animals,  ventilator  support  was   discontinued following anesthesia and administration of Metubine.  The endotracheal tube was clamped and the ischemic episode was considered to have begun when cardiac arrest was documented by absent EKG.

After the start of the ischemic episode the animals were  allowed to  remain on the operating table at room temperature ( 22°C to  25°C) for  a  30  minute period to simulate  the  typical  interval  between pronouncement  of legal death in a clinical environment and the  start  of  external cooling at that time.  During the 30 minute  normothermic ischemic  interval the femoral cut-down was performed  and  monitoring lines were placed in the right femoral artery and vein as per the  FGP animals.  Prior to placement, the monitoring catheters were  irrigated with normal saline, and following placement the catheters were  filled with 1000 unit/mL of sodium heparin to guard against clot  obstruction of the catheter during the post-arrest ischemic period.

Figure 4: Typical cooling curve of FIGP animals to ~1°C following cardiac arrest.

After the 30 minute normothermic ischemic period the animals were placed  in  a  1-mil polyethylene bag,  transferred  to  an  insulated container  in  which  a bed of crushed ice had  been  laid  down,  and covered  over with ice.  A typical cooling curve for a FIGP animal  is presented in Figure 4. FIGP animals were stored on ice in this fashion for a period of 24 hours, after which time they were removed from  the container and prepared for perfusion using the surgical and  perfusion protocol described above.

Perfusate

 TABLE I

 Perfusate Composition

Component                                           mM

Potassium Chloride                                  2.8

Dibasic Potassium Phosphate                 5.9

Sodium Bicarbonate                               10.0

Sodium Glycerophosphate                   27.0

Magnesium Chloride                               4.3

Dextrose                                                   11.0

Mannitol                                                118.0

Hydroxyethyl Starch                         50 g/l

The  perfusate  was an intracellular formulation  which  employed sodium  glycerophosphate  as the impermeant species  and  hydroxyethyl starch  (HES)(av.  MW   400,000  -  500,000)  as  the  colloid.    The composition of the base perfusate is given in Table I.  The pH of  the perfusate  was adjusted to 7.6 with potassium hydroxide.  A  pH  above 7.7, which would have been “appropriate” to the degree of  hypothermia experienced  during cryoprotective perfusion (9), was  not  achievable with  this mixture owing to problems with complexing of magnesium  and calcium   with  the  phosphate  buffer,  resulting  in  an   insoluble precipitate.

Perfusate components were reagent or USP grade and were dissolved in USP grade water for injection.  Perfusate was pre-filtered through a Whatman GFB glass filter (a necessary step to remove precipitate)  and then passed through a Pall 0.2 micron filter prior to loading into the extracorporeal circuit.

Perfusion

Perfusion  of both groups of animals was begun by carrying out  a total body washout (TBW) with the base perfusate in the absence of any cryoprotective agent.  In the FGP group washout was achieved within  2 –  3 minutes of the start of open circuit asanguineous perfusion at  a flow rate of 160 to 200 mL/min and an average perfusion pressure of 40 mm Hg.   TBW  in  the  FGP  group  was  considered  complete  when  the hematocrit  was  unreadable and the venous effluent was  clear.   This typically was achieved after perfusion of 500 mL of perfusate.

Complete blood washout in the FIGP group was virtually impossible to  achieve (see “Results” below).  A decision was made prior  to  the start  of  this  study (based on  previous  clinical  experience  with ischemic human cryopreservation patients) not to allow the  arterial pressure  to  exceed  60  mm Hg for any  significant  period  of  time.  Consequently, peak flow rates obtained during both total body  washout and subsequent glycerol perfusion in the FIGP group were in the  range of 50-60 mL/min at a mean arterial pressure of 50 mm Hg.

Due to the presence of massive intravascular clotting in the FIGP animals  it  was necessary to delay placement of the  atrial  (venous) cannula (lest the drainage holes become plugged with clots) until  the large  clots present in the right heart and the superior and  inferior vena  cava  had been expressed through the atriotomy.  The  chest  was kept  relatively  clear of fluid/clots by active suction  during  this interval.   Removal  of  large clots and reasonable  clearing  of  the effluent  was usually achieved in the FIGP group after 15  minutes  of open  circuit asanguineous perfusion, following which the circuit  was closed and the introduction of glycerol was begun.

Figure 5: pH of non-ischemic Δ•▪*(FGP) and ischemic ●●●  (FIGP) cats during cryoprotective perfusion. The FIGP animals were, as expected, profoundly acidotic with the initial arterial pH being between 6.5 and 6.6.

The  arterial pO2 of animals in both the FGP and FIGP groups  was kept  between  600  mm Hg and 760 mm Hg throughout  TBW  and  subsequent glycerol  perfusion.  Arterial pH in the FGP animals was  between  7.1 and  7.7  and was largely a function of the degree of  diligence  with which  addition of buffer was pursued.  Arterial pH in the FIGP  group was 6.5 to 7.3.  Two of the FIGP animals were not subjected to  active buffering during perfusion and as a consequence recovery of pH to more normal  values  from the acidosis of ischemia (starting  pH  for  FIGP animals was typically 6.5 to 6.6) was not as pronounced (Figure 5).

Figure 6: Calculated versus actual increase in arterial and venous glycerol concentration in the FGP animals. Arrow indicates actual time of termination of perfusion.

Introduction  of glycerol was by constant rate addition  of  base perfusate  formulation  made up with 6M glycerol  to  a  recirculating reservoir  containing 3 liters of glycerol-free base  perfusate.   The target  terminal tissue glycerol concentration was 3M and  the  target time  course for introduction was 2 hours.  The volume of 6M  glycerol concentrate  required  to  reach  a  terminal  concentration  in   the recirculating   system  (and  thus  presumably  in  the  animal)   was calculated as follows:

Vp

Mc = ——— Mp

Vc + Vp

where

Mc = Molarity of glycerol in animal and circuit.

Mp = Molarity of glycerol concentrate.

Vc = Volume of circuit and exchangeable volume of animal.*

Vp = Volume of perfusate added.

* Assumes an exchangeable water volume of 60% of the pre-perfusion  weight of the animal.

Glycerolization  of  the FGP animals was carried out at  10°C  to 12°C.   Initial  perfusion  of FIGP animals was at  4°C  to  5°C  with warming  (facilitated  by  TBW with warmer perfusate  and  removal  of surface  ice packs) to 10°-12°C for cryoprotectant introduction.   The lower  TBW  temperature of the FIGP animals was a consequence  of  the animals  having  been refrigerated on ice for the 24  hours  preceding perfusion.

Following  termination  of the cryoprotective ramp,  the  animals were  removed  from bypass, the aortic cannula was left  in  place  to facilitate  prompt reperfusion upon rewarming, and the venous  cannula was removed and the right atrium closed.  The chest wound was  loosely closed using surgical staples.

Concurrent with closure of the chest wound, a burr hole craniotomy 3  to  5  mm in diameter was made in the right parietal  bone  of  all animals  using a high speed Dremel “hobby” drill.  The purpose of  the burr hole  was  to  allow for  post-perfusion  evaluation  of  cerebralvolume, assess the degree of blood washout in the ischemic animals and facilitate  rapid expansion of the burr hole on re-warming to allow  for the visual evaluation of post-thaw reperfusion (using dye).

The  rectal  thermistor probe used to  monitor  core  temperature during  perfusion was replaced by a copper/constantan thermocouple  at the  conclusion  of perfusion for monitoring of the  core  temperature during cooling to -79°C and -196°C.

Cooling to -79°C

Figure 7: Representative cooling curve (esophageal and rectal temperatures) of FGP and FIGP animals from ~ 10°C to ~ -79°C. The ragged curve with sharp temperature excursions and rebounds is an artifact of the manual control of temperature descent via the addition of chunks of dry ice.

Cooling  to -79°C was carried out by placing the  animals  within two 1 mil polyethylene bags and submerging them in an isopropanol bath which  had  been  pre-cooled to -10°C.   Bath  temperature  was  slowly reduced  to  -79°C  by the periodic addition of dry  ice.   A  typical cooling curve obtained in this fashion is shown in Figure 7.   Cooling was at a rate of approximately 4°C per hour.

Cooling to and Storage at -196°C

Figure 8: Animals were cooled to -196°C by immersion in liquid nitrogen (LN2) vapor in a Linde LR-40 cryogenic dewar. When a core temperature of ~-180 to -185°C was reached, the animals were immersed in LN2.

Following cooling to -79°C, the plastic bags used to protect  the animals  from  alcohol were removed, the animals  were  placed  inside nylon  bags with draw-string closures and were then positioned atop  a 6″ high aluminum platform in an MVE TA-60 cryogenic dewar to which 2″-3″ of liquid nitrogen had been added.  Over a period of  approximately 15  hours  the liquid nitrogen level was gradually  raised  until  the animal  was  submerged.  A typical cooling curve  to  liquid  nitrogen temperature  for animals in this study is shown in Figure 8.   Cooling rates to liquid nitrogen temperature were approximately 0.178°C per  hour.  After  cool-down  animals  were maintained in liquid  nitrogen  for  a period  of  6-8  months until being removed  and  re-warmed  for  gross structural, histological, and ultrastructural evaluation.

Re-warming

Figure 9: Rewarming of all animals was accomplished by removing the animals from LN2 and placing them in a pre-cooled box insulated with 15.2 cm of polyurethane (isocyothianate) foam to which 1.5 L of LN2 (~2 cm on the bottom of the box)  of LN2 had been added. When the core temperature of the animals reached -20°C the animals were transferred to a mechanical refrigerator at 3.4°C.

The  animals  in  both groups were re-warmed to -2°C  to  -3°C  by removing them from liquid nitrogen and placing them in a pre-cooled box insulated on all sides with a 10.2 cm thickness of Styrofoam and containing a small quantity of liquid nitrogen.  The animals were then allowed to re-warm to approximately -20°C, at which time they were transferred  to a  mechanical  refrigerator at a temperature of 8°C.   When  the  core temperature  of the animals had reached -2°C to -3°C the animals  were removed to a bed of crushed ice for dissection, examination and tissue collection  for  light and electron microscopy.  A  typical  re-warming curve is presented in Figure 9.

Modification of Protocol Due To Tissue Fracturing

After the completion of the first phase of this study  (perfusion and  cooling  to  liquid nitrogen temperature)  the  authors  had  the opportunity  to evaluate the gross and histological condition  of  the remains  of three human cryopreservation patients who  were  removed from  cryogenic  storage  and  converted  to  neuropreservation  (thus allowing  for post-arrest dissection of the body, excluding the  head) (10).  The results of this study confirmed previous, preliminary, data indicative of gross fracturing of organs and tissues in animals cooled to  and  re-warmed from -196°C.  These findings led us to  abandon  our plans  to  reperfuse  the  animals  in  this  study  with  oxygenated, substrate-containing  perfusate  (to have been  followed  by  fixative perfusion  for histological and ultrastructural evaluation) which  was to be have been undertaken in an attempt to assess post-thaw viability by  evaluation  of post-thaw oxygen consumption, glucose  uptake,  and tissue-specific enzyme release.

Re-warming  and  examination  of the first  animal  in  the  study confirmed  the presence of gross fractures in all organ systems.   The scope  and severity of these fractures resulted in disruption  of  the circulatory system, thus precluding any attempt at reperfusion as  was originally planned.

Preparation of Tissue Samples For Microscopy

Fixation

 TABLE II.

 Composition Of Modified Karnovsky’s Solution

Component                             g/l

Paraformaldehyde                 40

Glutaraldehyde                      20

Sodium Chloride                      0.2

Sodium Phosphate                   1.42

Calcium Chloride                    2.0 mM

pH adjusted to 7.4 with sodium hydroxide.

Samples of four organs were collected for subsequent histological and  ultrastructural  examination:  brain, heart,  liver  and  kidney.  Dissection  to  obtain  the tissue samples was begun as  soon  as  the animals  were  transferred to crushed ice.  The brain  was  the  first  organ  removed  for sampling.  The burr hole created at  the  start  of perfusion  was  rapidly extended to a full craniotomy  using  rongeurs (Figure  14).   The  brain was then removed en bloc to  a  shallow  pan containing  iced,  modified Karnovsky’s fixative  containing  25%  w/v glycerol  (see  Table  II  for composition)  sufficient  to  cover  it.  Slicing of the brain into 5 mm thick sections was carried out with the brain  submerged  in fixative in this manner.  At  the  conclusion  of slicing  a 1 mm section of tissue was excised from the  visual  cortex and  fixed  in a separate container for electron  microscopy.   During final  sample  preparation for electron microscopy care was  taken  to avoid  the  cut  edges  of the tissue block  in  preparing  the  Epon embedded sections.

Figure 10: The sagitally sectioned (5 mm thickness) brains of the animals were placed in a  perforated basket immersed in Karnofsky’s fixative. This assembly was placed atop a magnetic stirring table and the fixative was gently  stirred with a magnetic stirring bar.

      The  sliced  brain  was  then placed in  350  ml  of  Karnovsky’s containing  25%w/v glycerol in a special stirring apparatus  which  is illustrated  in Figure 10.  This  fixation/de-glycerolization  apparatus consisted of two plastic containers nested inside of each other atop a magnetic stirrer.  The inner container was perforated with numerous  3 mm holes and acted to protect the brain slices from the stir bar which continuously  circulated the fixative over the slices.   The  stirring reduced  the likelihood of delayed or poor fixation due to overlap  of slices  or stable zones of tissue water stratification.   (The  latter was a very real possibility owing to the high viscosity of the  25%w/v glycerol-containing Karnovsky’s.)

De-glycerolization of Samples

Figure 11: Following fixation, the tissues slices of all organs evaluated by microscopy were serially de-glycerolized using the scheme shown above. When all of the glycerol was unloaded from the tissues they were shipped in modified Karnovsky’s to outside laboratories for histological and electron microscopic imaging.

          To avoid osmotic shock all tissue samples were initially immersed in Karnovsky’s containing 25%w/v glycerol at room temperature and were subsequently  de-glycerolized  prior  to  staining  and  embedding   by stepwise    incubation    in   Karnovsky’s    containing   decreasing concentrations  of  glycerol  (see  Figure  11  for the de-glycerolization protocol).

Figure 12: Fixation and de-glycerolization set up employed to prepare tissues for subsequent microscopic examination. Karnofsky’s fixative (A) was added to the tissue slice fixation apparatus (B) and the tissue slices were then subjected to serial immersion in fixative bathing media containing progressively lower concentrations of glycerol (C) (see Figure 11).

      To  prepare  tissue sections from heart, liver,  and  kidney  for microscopy,  the  organs  were  first removed  en  bloc  to  a  beaker containing an amount of ice-cold fixative containing 25% w/v  glycerol sufficient  to cover the organ.  The organ was then removed to a  room temperature  work  surface at where 0.5 mm sections were made  with  a Stadie-Riggs microtome.  The microtome and blade were pre-wetted  with fixative,  and cut sections were irrigated from the microtome  chamber into  a beaker containing 200 ml of room-temperature fixative using  a plastic  squeeze-type  laboratory  rinse  bottle  containing  fixative solution.   Sections  were  deglycerolized using  the  same  procedure previously detailed for the other slices.

Osmication and Further Processing

At  the  conclusion  of de-glycerolization of  the  specimens  all tissues  were  separated into two groups; tissues to be  evaluated  by light microscopy, and those to be examined with transmission  electron microscopy.   Tissues for light microscopy were shipped  in  glycerol-free  modified  Karnovsky’s solution to American  Histolabs,  Inc.  in Rockville,  MD  for  paraffin  embedding,  sectioning,  mounting,  and staining.

Tissues   for  electron  microscopy  were  transported   to   the facilities  of the University of California at San Diego in  glycerol-free  Karnovsky’s at 1° to 2°C for osmication, Epon embedding, and  EM preparation of micrographs by Dr. Paul Farnsworth.

Due  to  concerns  about the osmication and  preparation  of  the material processed for electron microscopy by Farnsworth, tissues from the  same  animals  were also submitted  for  electron  microscopy  to Electronucleonics of Silver Spring, Maryland.

III. EFFECTS OF GLYCEROLIZATION

 Perfusion of FGP Animals

Blood  washout  was  rapid and complete in the  FGP  animals  and vascular  resistance  decreased  markedly  following  blood   washout.  Vascular  resistance increased steadily as the glycerol  concentration increased,  probably  as a result of the increasing viscosity  of  the perfusate.

Within   approximately  5  minutes  of  the  beginning   of   the cryoprotective ramp, bilateral ocular flaccidity was noted in the  FGP animals.   As  the perfusion proceeded, ocular  flaccidity  progressed until  the  eyes had lost approximately 30% to 50%  of  their  volume.

Gross  examination  of the eyes revealed that initial water  loss  was primarily  from the aqueous humor, with more significant  losses  from the posterior chamber of the eyes apparently not occurring until later in  the  course  of  perfusion.  Within 15 minutes  of  the  start  of glycerolization  the corneal surface became dimpled and irregular  and the eyes had developed a “caved-in” appearance.

Dehydration  was also apparent in the skin and  skeletal  muscles and  was  evidenced  by  a marked decrease  in  limb  girth,  profound muscular  rigidity,  cutaneous  wrinkling (Figure 11),  and  a  “waxy-leathery” appearance and texture to both cut skin and skeletal muscle.

Tissue water evaluations conducted on ileum, kidney, liver, lung,  and skeletal  muscle  confirmed  and  extended  the  gross   observations.

Figure 13: Cutaneous dehydration following glycerol perfusion is evidenced by washboard wrinkling of the thoraco-abdominal skin (CD). The ruffled appearance of the fur on the right foreleg (RF) is also an artifact of cutaneous dehydration. The sternotomy wound, venous cannula and the Weitlaner retractor (R) and the retractor blade (RB) holding open the chest wound are visible at the upper left of the photo.

Preliminary  observation suggest that water loss was in the  range  of 30%  to 40% in most tissues. As can be seen in Table III,  total  body water  losses  attributable  to dehydration, while  typically  not  as profound, were still in the range of 18% to 34%.  The gross appearance of  the heart suggested a similar degree of dehydration, as  evidenced by modest shrinkage and the development of a “pebbly” surface  texture and a somewhat translucent or “waxy” appearance.

TABLE III.

 Total Water-Loss Associated With Glycerolization of the Cat

____________________________________________________

Animal    Pre-Perfusion    Post-Perfusion     Kg./     % Lost As     

  #          Weight Kg.        Weight        Water     Dehydration

 FGP-1          4.1                    3.6           2.46                 18

FGP-2          3.9                    3.1           2.34                 34

FGP-3          4.5                    3.9           2.70                 22

FGP-4          6.0                    5.0           3.60                 28

FIGP-1         3.4                    3.0           2.04                 18

FIGP-2         3.4                    3.2           2.04                   9

FIGP-3         4.32                 3.57          2.59                29

 

Figure 14: Cerebrocortical dehydration as a result of 4M glycerol perfusion. The cortical surface (CS) is retracted ~5-8 mm below the margin of the cranial bone (CB).

Examination  of  the cerebral hemispheres through the  burr  hole (Figure  14) and of the brain in the brain brainpan (Figure 19) revealed an estimated 30% to 50% reduction  in  cerebral volume,  presumably  as a result of osmotic dehydration  secondary  to glycerolization.   The cortices also had the “waxy”  amber  appearance previously observed as characteristic of glycerolized brains.

The  gross  appearance  of the kidneys,  spleen,  mesenteric  and subcutaneous  fat, pancreas, and reproductive organs  (where  present) were   unremarkable.   The  ileum  and  mesentery  appeared   somewhat dehydrated,  but  did  not  exhibit  the  waxy  appearance  that   was characteristic of muscle, skin, and brain.

Figure 15: Oxygen consumption was not apparently affected by glycerolization as can be seen in the data above from the perfusions of FGP-5 and FGP-5.

Oxygen  consumption (determined by measuring the  arterial/venous difference)  throughout  perfusion  was fairly constant  and  did  not appear to be significantly impacted by glycerolization, as can be seen Figure 12.

Perfusion of FIGP Animals

As previously noted, the ischemic animals had far lower flow rates at  the  same  perfusion  pressure as  FGP  animals  and  demonstrated incomplete  blood  washout.   Intravascular  clotting  was  serious  a barrier  to  adequate perfusion.   Post-thaw  dissection  demonstrated multiple  infarcted areas in virtually all organ systems; areas  where blood  washout  and  glycerolization were incomplete  or  absent.   In contrast  to  the even color and texture changes observed in  the  FGP animals,  the  skin of the FIGP animals  developed  multiple,  patchy, non-perfused   areas  which  were  clearly  outlined  by   surrounding, dehydrated, amber-colored glycerolized areas.

External  and internal examination of the brain and  spinal  cord revealed  surprisingly  good  blood washout  of  the  central  nervous system.  While grossly visible infarcted areas were noted, these  were relatively  few  and  were generally no larger than 2 mm to  3  mm  in diameter.   With few exceptions, the pial vessels were free  of  blood and appeared empty of gross emboli.  One striking difference which was consistently  observed  in  FIGP  animals  was  a  far  less  profound reduction  in brain volume during glycerolization (Figure  17).   This may  have  been due to a number of factors: lower flow  rates,  higher perfusion  pressures,  and the increased  capillary  permeability  and perhaps increased cellular permeability to glycerol.

Figure 16: The eye of an FGP animal following cryopreservation. The cornea has  become concave due to the glycerol-induced osmotic evacuation of the aqueous humor. The vitreous humor is completely obscured by the lens which has become white and opaque as a result of the precipitation of the crystallin proteins in the lens.

Whereas   edema   was   virtually   never   a   problem    during glycerolization  of  FGP  animals, edema was  universal  in  the  FIGP animals  after as little as 30 minutes of perfusion.  In  the  central nervous  system this edema was evidenced by a “rebound”  from  initial cerebral  shrinkage  to  frank  cerebral  edema,  with  the  cortices, restrained by the dura, often abutting or slightly projecting into the burr hole.   Marked  edema of the nictating membranes,  the  lung,  the intestines,  and  the  pancreas  was also a  uniform  finding  at  the conclusion  of cryoprotective perfusion.  The development of edema  in the central nervous system sometimes closely paralleled the  beginning of “rebound” of ocular volume and the development of ocular turgor and frank ocular edema.

Figure 17: The appearance of the brain of an FIGP animal following cryoprotective perfusion as seen through a craniotomy performed over the right temporal lobe. The cortical surface (CS) is retracted ~3-5 mm from the cranial bone (CB) and appears

In contrast to the relatively good blood washout observed in  the brain,  the  kidneys  of  FIGP animals had a  very  dark  and  mottled appearance.   While  some  areas (an estimated  20%  of  the  cortical surface) appeared to be blood-free, most of the organ remained  blood-filled throughout perfusion.  Smears of vascular fluid made from renal biopsies  which  were collected at the conclusion  of  perfusion  (for tissue  water determinations) revealed the presence of many  free  and irregularly clumped groups of crenated and normal-appearing red cells, further evidence of the incompleteness of blood washout.   Microscopic examination  of recirculating perfusate revealed some free, and a  few clumped  red  cells.   However, the concentration  was  low,  and  the perfusate  microhematocrit  was  unreadable  at  the  termination   of perfusion (i.e., less than 1%).

The  liver  of  FIGP  animals  appeared  uniformly   blood-filled throughout  perfusion,  and  did not exhibit even  the  partial  blood washout evidenced by the kidneys.  However, despite the absence of any grossly  apparent blood washout, tissue water evaluations in one  FIGP animal  were  indicative  of  osmotic dehydration  and  thus  of  some perfusion.

The mesenteric, pancreatic, splanchnic, and other small  abdominal vessels  were  largely free of blood by the conclusion  of  perfusion.  However,  blood-filled  vessels  were not  uncommon,  and  examination during   perfusion   of   mesenteric   vessels   performed   with   an ophthalmoscope  at 20x magnification revealed stasis in  many  smaller vessels, and irregularly shaped small clots or agglutinated masses  of red  cells in most of the mesenteric vessels.   Nevertheless,  despite the   presence  of  massive  intravascular  clotting,  perfusion   was possible, and significant amounts of tissue water appear to have  been exchanged for glycerol.

One  immediately  apparent difference between the  FGP  and  FIGP animals  was  the  accumulation in the lumen of  the  ileum  of  large amounts  of  perfusate  or perfusate  ultrafiltrate  by  the  ischemic animals.  Within approximately 10 minutes of the start of reperfusion, the  ileum  of the ischemic animals that had  been  laparotomized  was noticed  to  be  accumulating fluid.  By the  end  of  perfusion,  the stomach  and the small and large bowel had become massively  distended with  perfusate.   Figure  14 shows both FIGP and  FGP  ileum  at  the conclusion  of glycerol perfusion.  As can be clearly seen,  the  FIGP intestine  is markedly distended.  Gross examination of the  gut  wall was   indicative  of  tissue-wall  edema  as  well   as   intraluminal accumulation  of  fluid.  Often by the end of perfusion, the  gut  had become  so  edematous  and  distended  with  perfusate  that  it   was impossible  to completely close the laparotomy  incision.   Similarly, gross  examination of gastric mucosa revealed severe erosion with  the mucosa being very friable and frankly hemorrhagic.

Escape  of  perfusate/stomach contents from the  mouth  (purging) which occurs during perfusion in ischemically injured human suspension patients did not occur, perhaps due to greater post-arrest  competence of the gastroesophageal valve in the cat.

Oxygen  consumption  in  the two ischemic cats in  which  it  was measured  was dramatically impacted, being only 30% to 50% of  control and deteriorating throughout the course of perfusion (Figure 12).

IV. GROSS EFFECTS OF COOLING TO AND REWARMING FROM -196°C

The  most striking change noted upon thawing of the  animals  was the presence of multiple fractures in all organ systems.  As had  been previously noted in human cryopreservation patients, fracturing  was most pronounced in delicate, high flow organs which are poorly  fiber-reinforced.   An exception to this was the large arteries such as  the aorta, which were heavily fractured.

Fractures  were most serious in the brain, spleen, pancreas,  and kidney.   In these organs fractures would often completely  divide  or sever  the  organ  into one or more discrete  pieces.   Tougher,  more fiber-reinforced tissues such as myocardium, skeletal muscle, and skin were less affected by fracturing; there were fewer fractures and  they were smaller and less frequently penetrated the full thickness of  the organ.

Figure 18: All of the animals in the study exhibited fractures of the white matter that transected the brain between the cerebellum and the cerebral cortices. Similarly, the spinal cord was invariable severed by fractures in several locations and exhibited the appearance of a broken candle stick. The yellow box encloses a sampling area used to determine brain water content.

Figure 19: Deep fracture of the left occipital cortex. Note the absence oif fracturing in the adjacent skeletal muscle (M) observed in FGP-1. Note that the brain appears shrunken and retracted in the brainpan.

Figure 20: Appearance of the brain after removal from the brainpan. There is a massive fracture of thew right frontal=temporal cortex which penetrates the full thickness of the cerebral hemisphere to expose the right cerebral ventricle observed in FIGP-2. The cortex appears buff colored and gives the appearance of being incompletely washed out of blood.

Figure 21: Typical fracture sites in the brain (arrows and yellow shading). The olfactory cortices and the brainstem were invariably completely severed by fractures.

In both FGP and FIGP animals the brain was particularly  affected by  fracturing  (Figures 18, 19 & 22) and  it  was not uncommon to  find  fractures  in  the cerebral hemispheres penetrating through to the ventricles as seen  in Figure  20, or to find most of both cerebral hemispheres and the  mid-brain  completely  severed from the cerebellum by a  fracture  (Figure 18).  Similarly, the cerebellum was uniformly severed from the medulla at the foramen magnum as were the olfactory lobes, which were  usually retained  within  the olfactory fossa with severing  fractures  having occurred at about the level of the transverse ridge.  The spinal  cord was  invariably transversely fractured at intervals of 5 mm to  15  mm over  its  entire  length (Figure 21).  Bisecting CNS fractures  were  most  often observed  to  occur  transversely  rather  than  longitudinally.   In general,  roughly  cylindrical structures such as  arteries,  cerebral hemispheres, spinal cord, lungs, and so on are completely severed only by transverse fractures.  Longitudinal fractures tend to be shorter in length and shallower in depth, although there were numerous exceptions to this generalization.

Figure 22: Crisp olfactory lobe fracture which also partially penetrated the pia matter in FGG-4.

In  ischemic animals the kidney was usually grossly fractured  in one  or  two locations (Figure 25).  By  contrast,  the  well-perfused kidneys of the non-ischemic FGP group exhibited multiple fractures,  as can  be  seen in Figure 24.  A similar pattern was observed  in  other organ  systems  as well; the non-ischemic animals  experienced  greater fracturing injury than the ischemic animals, presumably as a result of the   higher   terminal  glycerol  concentrations  achieved   in   the non-ischemic group.

Figure 23: Appearance of a fractured kidney before removal of the renal capsule. The renal capsule has only one fracture, however when the capsule is removed, the extensive fracturing of the renal cortex and medulla become evident (Figure 24, below).

Figure 24: Fractured renal cortex from FGP-1 after removal of the renal capsule. The renal cortex is extensively fractured, the renal medulla slightly less so. Note the uniform, tan/light brown color of the cortex indicating complete blood washout and the absence of red cell trapping.

Cannulae  and attached stopcocks where they were externalized  on the  animals  were  also frequently  fractured.   In  particular,  the polyethylene pressure-monitoring catheters were usually fractured into many  small  pieces.   The  extensive  fracture  damage  occurring  in cannulae,  stopcocks, and catheters was almost certainly a  result  of handling  the animals after cooling to deep subzero  temperatures,  as this  kind of fracturing was not observed in these items upon  cooling to  liquid nitrogen temperature (even at moderate rates).  It is  also possible that repeated transfer of the animals after cooling to liquid nitrogen  temperature may have contributed to fracturing  of  tissues, although the occurrence of fractures in organs and bulk quantities  of water-cryoprotectant  solutions  in the absence of  handling  is  well documented in the literature (12, 13).

There were subtle post-thaw alterations in the appearance of  the tissues of all three groups of animals.  There was little if any fluid present  in the vasculature and yet the tissues exhibited  oozing  and “drip”  (similar to that observed in the muscle of frozen-thawed  meat and  seafood)  when cut.  This was most pronounced  in  the  straight-frozen  animal.  The tissues (especially in the ischemic  group)  also had  a somewhat pulpy texture on handling as contrasted with  that  of unfrozen,  glycerolized  tissues  (i.e.,  those  handled  during  pre-freezing  sampling for water content).  This was most in  evidence  by the accumulation during the course of dissection of small particles of what appeared to be tissue substance with a starchy appearance and  an oily  texture on gloves and instruments .  This phenomenon  was  never observed  when handling fresh tissue or glycerolized tissue  prior  to freezing and thawing.

There were marked differences in the color of the tissues between the three groups of animals as well.  This was most pronounced in  the straight-frozen  control  where the color of almost  every  organ  and tissue examined had undergone change.  Typically the color of  tissues in  the  straight-frozen animal was darker, and white  or  translucent tissues such as the brain or mesentery were discolored with hemoglobin released from lysed red cells.

Figure 25: The (ventral) dependent and dorsal (less dependent) surfaces of the right kidney from FIGP-1. There is extensive mottling evidencing incomplete blood washout despite perfusion with many liters of CPA solution. Fracturing is much less extensive than that observed in FGP animals not subjected to prolonged periods of post-arrest ischemia. Note the pink colored “drip” from the organ that is present on sectioning board.

Figure 26: Appearance of the kidney from FIGP-1 shown above on cross-section. The renal medulla appears congested and blood filled.

The FGP and FIGP groups did not experience the profound post-thaw changes  in tissue color experienced by the straight-frozen  controls, although  the  livers and kidneys of the FIGP  animals  appeared  very dark, even when contrasted with their pre-perfusion color as  observed in those animals laparotomized for tissue water evaluation.

END OF PART 1

 

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Science Fiction, Double Feature… http://chronopause.com/index.php/2011/07/30/science-fiction-double-feature/ http://chronopause.com/index.php/2011/07/30/science-fiction-double-feature/#comments Sat, 30 Jul 2011 11:13:35 +0000 admin http://chronopause.com/?p=1057 Continue reading ]]>

By Mike Darwin

I used to love science fiction. The trouble is that it simply became too believable to be any fun anymore. Space travel? Sure, everybody knows that’s possible, and thanks to Industrial Light & Magic, we all know what it will look like, too. Multiple universes? That’s almost received dogma in physics these days,[1] and it’s made it into Scientific American,[2] not once, but twice! You can turn on your TV and watch “Fringe” if you want to have an adventure in the universe next door. Yes, it has gotten really hard for a person to have a good time these days. So I was thinking, maybe I should sit down and write some uplifting cryonics science fiction. You know, the kind of really unbelievable stuff that get’s your pulse pounding and respiratory rate up – when you’re not holding your breath, that is! Because there sure isn’t much that’s very escapist or uplifting here on Chronosphere most of the time.

The question is, am I up to the task? The good ideas have already been well exploited by literary talents far greater than mine, and it’s hard to find inspiration for “the almost impossible” from the advancing front of science, these days. Or so I thought. Then I came across a remarkable new discovery, one made just this year, in fact. It turns out that there are two Alcors! That’s right, the “star” we’ve called Alcor for about 500 years years is really two stars.[3] One star is your run of the mill M-type star, and the other is a small, dim red dwarf star about one fourth the mass of Sol. There is thus an Alcor-A and an Alcor-B. Wow! That really got me thinking, what if there were an Alcor-A and an Alcor-B cryonics organization?

Of course, we know all about Alcor-A, because we can see it. It’s everywhere; on TV, on the Internet, everywhere we look for information about cryonics. But what if there were an Alcor-B, sort of an alternate, utterly fantastical and impossible Alcor? An Alcor that could say, take $20 million dollars over 20 years or so, and, and…what? Well, in order to find out the answer to that question, you have to read my story. Now let me warn you that I’m not much of a story teller. My story is one of those newfangled ones, which has no beginning, no middle and no end! It’s just a press release by an alternate Alcor, Alcor-B. Alcor-B may seem much like Alcor-A, but I assure you that any resemblance is purely coincidental. They are enough alike, however, that I was able to use pictures, illustrations and the like from Alcor-A, to tell my story, and for that I am very grateful.

Similarly, I do what most science fiction writers do. I build heavily on existing science. Even though my story is utterly incredible, indeed completely impossible (like time travel or faster than light travel), I need the real science to try to persuade my readers (you) to suspend your disbelief just long enough to read the story through, and hopefully to thoroughly enjoy it. My premise is simple. Just a few days from now on 06 August, 2011, in a universe much like ours, a cryonics organization called Alcor-B holds a press conference and makes the following announcement. Regrettably, due to constraints on data transmission between adjacent universes, all we are able to retrieve from that event is the media handout. And so, without further ado, here it is.

An Extensive Press Briefing from the Alcor-B Foundation on the Debut of its Novel Near Vitrification Cryopreservation Technology for Humans

Alcor-B Cryopreservation Research Foundation (ABCRF)

FOR IMMEDIATE RELEASE

06 August, 2006

ALCOR-B FOUNDATION DEVELOPS NEAR VITRIFICATION TECHNOLOGY (NVT)

NEAR PERFECT STRUCTURAL

PRESERVATION OF THE HUMAN BRAIN ACHIEVED

 Figure 1: The Alcors are the second, smaller and dimmer companion stars to the Mizars, the bright stars that comprise the crook in the handle of the Big Dipper constellation. In the Arab world of the 5th Century CE, Mizar’s much less bright (and more difficult to see) companion stars, Alcor-A and Alcor-B, were used as tests for good vision. Only someone with the clearest and most acute vision could see the Alcor’s. Alcor-B was discovered early in 2011 using Project 1640m, which makes use of the Hale Telescope’s adaptive optics system. Project 1640 gives the Hale a view almost equal to what is possible in space with the Hubble telescope. The instrument also has the ability to block out the light of a star, allowing faint objects located next to a star to be seen. The Hale, armed with Project 1640, was pointed at Alcor earlier this year and found that it isn’t a single star. Alcor has a small stellar companion that hadn’t been seen before: Alcor-B, a small, dim, red dwarf star about one fourth the mass of our Sun. To see Alcor-B you must have the superior vision that only mastery of the most sophisticated technology allows. Alcor-B is thus a test for the clearest and most acute vision – vision capable of seeing things as they really are – not just as they appear to be.

Introduction

Over the past five years the Alcor-B Cryobiology Research Foundation (Alcor-B) has been working to develop a fundamentally new and profoundly improved human cryopreservation technology platform.  We have expended $3.5 million dollars on this effort and what we have developed is nothing less than a quantum advance in the quality of cryopreservation now available to Alcor-B patients who present for treatment under optimum conditions.

Figure 2: At left, above, is a light micrograph (400x) of the molecular layerof the rabbit cerebral cortex subjected to freezing to -79oC in the absence of cryoprotection (straight freezing). The tissue is compressed between blocks of ice that have osmotically extracted the intracellular water. At right is the molecular layer of rabbit cerebral cortex tissue (10,000x) following thawing and fixation after straight freezing. The ultrastructure of the tissue resembles that of a tissue homogenate, rather than that of the molecular layer of the cerebral cortex.[4]

Previous cryopreservation techniques have relied on freezing, usually after the introduction of a cryoprotective chemical(s) to reduce the amount of ice being formed. While this technology reduces the amount of freezing injury that occurs when human patients are cryopreserved, there is still a great deal of serious disruption of the fine structure of the brain (ultrastructure) that will require very sophisticated molecular-level repair by a mature nanotechnology – a technology that is likely to be many decades, or even a century or more in the future. Alcor-B’s development of minimal ice, or Near-Vitrification Technology (NVT) all but eliminates damage from ice formation. In fact, in experimental animals subjected to Alcor-B  NVT, damaging ice formation is confined to a few small areas of the brain comprising less than 1% of total brain volume. Similarly, NVT, delivered under optimal conditions, results in only approximately 3-5% ice formation in entire body of dogs subjected to this procedure.

What is NVT?

Under normal conditions, when a living system is cooled, the water in it, which comprises about 60% of its mass, is converted into ice. This ice forms outside of cells, not inside of them, and in the process the cells become dehydrated and shrunken. This dehydration due to ice formation increases the concentration of the salts normally present in body fluids, which in turn causes chemical injury to the proteins and the lipids (fats) that make-up the cells’ structures (Figures 2 & 3). The addition of modest (10-20% w/v) or moderate (20-50%) amounts of cryoprotective agents which do not freeze, and which interact with cellular water to reduce the amount of that water which freezes during cooling, markedly reduces freezing damage.

Figure 3: A ribbon model of a protein depicting the kind of conformational changes typically seen in protein denaturation as a result of freezing injury.

Figure 4: Above, top, shows a false-color rendering of the normal configuration of membrane lipids and the membrane protein sodium-potassium-ATPase in a bacterial cell membrane. The membrane exhibits a smooth, lamellar character, and there are only a few aggregated and displaced particles of protein evident (yellow granules). In B, at right above, there is evidence of an alteration in membrane structure after the cell has been incubated at ~ -6oC for 1 hour in the presence of 20% w/v dimethylsulfoxide (DMSO). The membrane has developed a pebbly appearance and there are many extruded granules of protein on the membrane surface. The lower illustration (above) is a computer rendering of various lipid phase transitions in a model system (Langmuir trough), some of which result in perforations of the normally lamellar membrane structure.

In fact, such “cryo-protection” almost completely eliminates the damage that normally occurs to the lipids and proteins that cells are comprised of. This kind of cryopreservation technique is what forms the basis for the successful freeze-preservation of sperm, blood, bone marrow and many other types of cells and tissues that are amorphous in structure – in other words, cells and tissues where the cells are not attached to each other and organized in a highly structured way.

Figure 5: Typical representation of how freezing proceeds in cells and tissues. Ice begins forming outside cells, forming crystals of pure water. The salts and other solids that were formerly dissolved in the crystallized water are forced into a progressively smaller volume of unfrozen solution. This increase in the concentration of solids dissolved in the extracellular fluid osmotically extracts water from the cells, causing them to shrink. At ~ -20oC no further water can be converted into ice and the interior of the cells remains in an unfrozen state – a highly concentrated solution of cell proteins and salts, from both inside and outside the cells. With further cooling this electrolyte gel will be converted to a crystal free glass at ~ -100oC

Unfortunately, most multi-cellular animals, including human beings, consist of highly organized and structurally complex aggregations of cells which have specific jobs to do – jobs which can only be carried out if those structures are intact and un-disrupted. Ice formation in tissues can disrupt those important inter-cellular connections, and while the cells themselves may survive freezing and cryopreservation, the function of the tissue or organ is compromised (Figure 5).

Vitrification: A New Preservation Technology

Over the past two decades a new technology of cryopreservation has emerged and is being perfected. This technology is called “vitrification” (from the Latin vitrum, glass + Latin -ficre, -fy)because it completely suppresses the formation of damaging ice crystals during the cryopreservation process, as can be seen in Figure 6, below.

Figure 6: At bottom left a rabbit kidney that has been frozen following treatment with ~ 40% cryoprotectant agents. The kidney was submerged in solution that did not have enough cryoprotective agents present to allow it to vitrify. The kidney has a chalky, opaque appearance is due the presence of large amounts of ice in the tissue. At bottom right is a kidney that has been perfused and equilibrated with sufficient cryoprotectant to allow cooling to -140oC with no ice formation.  Because this kidney has no ice crystals in it to refract light, it remains translucent and appears unfrozen – which is in fact the case – even though it has been converted to a solid, glassy state.[43] At top; Even in the everyday world, the difference between ice and glass is clearly visible when the two are compared side by side.

This non-frozen glassy solid state is achieved by replacing ~60% of the water in the tissues of an organ, or a whole organism, with a combination of antifreeze molecules that completely prevent ice formation. The technique of vitrification as applied to whole organs is relatively new, and only recently has a whole mammalian organ, the rabbit kidney, been subjected to vitrification and recovered function. However, there are still many obstacles to be overcome before this technology can be routinely applied to organs to allow for the creation of organ banks, wherein a large reserve of organs and tissues can be stored indefinitely, for transplantation. And there are many additional obstacles to be overcome before whole organisms, such as human beings, can be cooled to very low temperatures for stable, indefinite storage.

Figure 7: Visual appearance of ice in a rabbit kidney that was cross-sectioned during rewarming. The kidney was perfused with a cryoprotective mixture called M22 at -22°C, cut in half, immersed in M22, vitrified at -135°C, and eventually re-warmed at ~1°C/min while being periodically photographed. Times (1:30 and 1:40) represent times in hours and minutes from the start of slow warming. The temperatures refer to ambient atmospheric temperatures near the kidney but not within the kidney itself. The upper panel shows the kidney at the point of maximum ice cross-sectional area, and the lower panel shows the kidney after complete ice melting. Both panels show the site of an inner medullary biopsy taken for differential scanning calorimetery in order to determine the actual concentration of cryoprotectants in the tissue with high precision. [http://cryoeuro.eu:8080/download/attachments/425990/FahyPhysicBiolAspectsRenalVitri2010.pdf?version=1&modificationDate=1285892563927]

The ability to cryopreserve people indefinitely would effectively allow for ‘medical time travel,’ whereby terminally ill patients with currently incurable illnesses could wait in suspended animation until medicine developed not just the cure for the particular disease that caused them to opt for cryopreservation, but also for aging and other degenerative diseases. Such a technology of fully reversible suspended animation would thus allow for a broad cross-section of the terminally ill population to have an opportunity to take advantage of indefinitely long lives in youthful good health, or in other words, what the neurosurgeon and medical commentator Dr. Sanjay Gupta, has termed “practical immortality.”

Near Vitrification Technology

Until suspended animation is developed it is necessary to cryopreserve today’s terminally ill patients with less than perfect techniques. These techniques inflict some injury, but we believe that this injury will be reversible in the future and we have excellent evidence right now that it is reversible, in principle. This is the theoretical underpinning of cryonics – the idea that if we cryopreserve today’s terminally ill patients with the best available techniques, it may well be possible to not only cure the lethal illness the patient is suffering from, but also to cure the damage incurred through the use of still imperfect cryopreservation techniques.

However, the damage inflicted by conventional freezing techniques is extensive, and it will take many decades, and perhaps even a century or two, before a mature “nanotechnology,” one capable of effecting repair at the molecular level, is likely to be developed. It would obviously be much better to be able to cryopreserve patients in such a way that the kind of damage being done could be reversed (and the patient restored to life) by biomedical technologies currently under development, and which may well become available within the next 30 to 60 years.

Alcor-B has been working relentlessly to develop such a cryopreservation platform and now, after 5 years and expenditure of $3.5 million dollars, we have succeeded. We call this cryopreservation modality Near Vitrification Technology (NVT). NVT is basically vitrification applied to the human body, or the human head in isolation, with the understanding that small islands of tissue will still be undergoing freezing, despite our best efforts to completely suppress ice formation. As you will see in the discussion that follows, the amount of ice that forms is surprisingly low; < 5% of the body as a whole and only ~1% of the brain.

It is important to point out that this ice formation is not global in nature, but rather is confined to a few tissues that are poorly circulated with blood under normal conditions, and are thus difficult to equilibrate with a sufficient amount of cryoprotectant to completely inhibit ice formation (Figure 7). It is also important to point out that even where some ice formation does take place and “freezing” occurs, it is freezing in the presence of very high concentrations of cryoprotectant drugs, and therefore the damage is much less than would be the case if freezing were to have occurred in the absence of cryoprotection.

Alcor B’s Laboratory Experience

To achieve NVT, Alcor-B is using technology similar to that developed by 21st Century Medicine (21CM), a cryobiological research and development company located in Fontana, CA. We have used M-22 solution, a vitrification solution developed by 21CM primarily for kidney vitrification. The composition of M-22 is shown Figure 8, below. This complex mixture of antifreeze and actively ice-growth inhibiting (ice-blocking) cryoprotectants exhibits comparatively low toxicity, even at concentrations of ~60%. A unique feature of M-22 is the presence of two synthetic molecules that inhibit ice growth by binding to both the  a and c axes of ice. These molecules stabilize the solution against ice nucleation and propagation, allowing for use of the much slower cooling and rewarming rates needed for ice free cryopreservation of large tissues masses, such as humans organs or entire human beings.

Figure 8: Twenty First Century Medicine’s M-22 vitrification solution contains 5 penetrating colligative cryoprotective agents as well as 6% of non-penetrating polymers – two of which are highly active ice-blocking molecules; Supercool X-1000 and Supercool Z-1000. X-1000 contains 80% of the syndiotactic stereochemical form of polyvinyl alcohol and 20% vinyl acetate and Z-1000 is a linear polymer of polyglcerol with an average molecular weight of 750 Da. Both bind to the a and c axes of ice crystals, stabilizing solutions they are present in against ice formation during slow rates of cooling and rewarming.[95

A fair summary of the current technological state of the art with respect to the vitrification of organs for the purpose of developing organ banks is that under ideal (laboratory) conditions it is likely now possible to place complex mammalian organs, such as the rabbit kidney, into indefinitely long suspended animation with little or no loss of viability, and no damage as a consequence of structural disruption due to ice formation. The use of radio frequency, or microwave illumination to speed rewarming, the use of warm gas (such as helium) to perfuse the organ’s circulation, or a combination of these modalities, may offer a workable solution to the problem of ice formation during rewarming. Perhaps most impressively, one mammalian kidney has survived vitrification and rewarming sufficiently intact to permit immediate support of the rabbit from which it was removed (as the sole kidney), until the animal was sacrificed for evaluation 29 days after the organ was re-implanted.

Figure 9: The first kidney to survive vitrification shortly before it was removed from the animal for evaluation after supporting its life as the sole kidney for 29 days.[5]

It is not possible to directly apply the 21CM vitrification technology to humans, or to the human brain, because of constraints on the rate at which the necessary cryoprotective drugs can be loaded into and unloaded from the brain. Kidneys can be perfused with M-22 to temperatures as low as -20oC, whereas the brain can be perfused only to -3-4 oC. This means that the brain will be exposed to toxicity from the cryoprotectants in the vitrification solution, which cause injury very much like that shown in Figures 4 & 5 above – although much, much less extensively. Alcor-B research indicates that perhaps a total of 25 proteins undergo some kind of denaturation, and that fewer than 20% of the cells in an animal treated with NVT undergo alterations in membrane structure that would interfere with function upon reanimation.

Viability studies conducted by Alcor-B indicate that even with extended exposure to M-22 at -3oC, there is recovery of ~40% of pre-preservation viability (as measured by Na++/K+ ratio). Very importantly, two dog brains out of a series of 17, subjected to NVT and stored for 7 and 11 days, respectively, at -130oC, demonstrated brief recovery of electrical activity (EEG). Rabbit brain slices treated with M-22 in the laboratories of 21CM, have demonstrated complete recovery of viability, electrical activity and Long Term Potentiation (LTP). Importantly, LTP is the biochemical change in brain cells currently thought to encode memory. Brain slices in which LTP was induced, by simulating a learning experience with a weak electrical current, were able to ‘recall’ this event following cryopreservation and reanimation.

An additional complicating factor in achieving reversible (viable) vitrification of the mammalian brain has been the inability to continue cryoprotectant perfusion at the same subzero temperatures (-20oC) that have proven essential for recovery of rabbit kidneys following loading and unloading with M-22. As can be seen in Figure 10, below, perfusion of the terminal concentration of M-22 is not possible below ~ -3-4oC. Exposure to ~8.2M M-22 at such a relatively high temperature, for the final ~60 min of perfusion required to load the brain with the CPA mixture, results in major loss of viability, but does not visibly affect brain ultrastructure, as imaged using Transmission Electron Microscopy (TEM).

Figure 10: Cryoprotection and cooling protocol used to achieve structural vitrification of the rabbit brain at 21st Century Medicine, Inc., CPA loading commences at a temperature of ~+4oC and continues at that temperature for ~ 60 minutes while the M-22 concentration is gradually increased to ~4 M. The temperature is then reduced to ~ -3oC while the CPA concentration is increased to ~ 8M. The total time required to achieve full equilibration of the brain with M-22 is ~ 180 minutes, after which the organ is immediately transferred to an air-blast cooler for very rapid cooling to ~ -135oC. [Image is courtesy of Brian Wowk, Ph.D., of 21st Century Medicine, Inc., http://www.21cm.com/]

The ultrastructure of dog brains cryopreserved using the 21CM vitrification technique shows no evidence of gross ice formation, as can be seen in the photo at the top of Figure 11, below. Indeed, there is no evidence of ice formation in any of the tissues of the head and neck with simple visual inspection.

Figure 11: Dog brains subjected to NVT under optimum laboratory conditions show no visual evidence of ice formation. However, when false-color, polarized light imaging is used, areas of minimal ice formation can be seen. Measurements of the ice content in the brain regions seen to contain ice (as above) using differential scanning calorimetery typically show ice formation in the range of 4-12% of the tissues volume. A=brain, B=space from cryoprotectant-induced brain dehydration, C=spinal cord, D=soft palate.

However, if the exposed tissues of the brain and head are subjected to false-color, polarized light imaging, the areas where ice has formed become visible as green, highlighted areas. As can be seen in Figure 11, above, small amounts of ice have formed in several brain areas, as well as in the muscle of the neck, and in the frontal sinus. The rest of the brain appears ice free, fully vitrified, and thus spared any mechanical disruption of the tissues.

Figure 12: Sections of the experimental animals were cut at deep subzero temperatures using a specially modified Bright Instruments 8000 (BI-8000) sledge microtome with electro-linear drive (left, above). The modified BI-8000 can section specimens up to 250mm long, and is liquid nitrogen cooled to maintain stable temperatures during sectioning, and to avoid artifact-crystallization due to inadvertent re-warming. The BI-8000 employs a fully automated cutting sequence and an electro-linear drive for high cutting forces. Cut sections were then removed from the BI-8000 and photographed for subsequent analysis of the effects of the NVT procedure on the tissues, including polarimetric evaluation of ice formation (e.g., when and where it occurred).

In order to resolve the question of whether or not ice is forming at the cellular and intra-cellular level, Alcor-B has conducted extensive Transmission Electron Microscopy (TEM) studies of animals’ brains subjected to NVT. Exposure to the vitrifying cryoprotectants results in extensive (but fully reversible) dehydration of the tissues (Figure 11) and this makes interpreting the TEM pictures more difficult. Aside from increased density of the ground substance (which is the molecular fabric of the brain) due to dehydration, the brain cells (neurons), their long processes (axons) and their connections (synapses) are intact.  As is evident in Figures 13-15, the architecture of NVT treated brains is essentially normal (aside from the cryoprotectant-induced dehydration). Cell membranes are crisp and intact, as are the intra-cellular membranes, including the synaptic vesicles that contain neurotransmitting chemicals.

Figure 13: TEM of rabbit cerebral cortex gray matter (~ 15,000x) subjected to vitrification, rewarming and perfusion fixation using M-22 and the perfusion protocol shown in Figure 10, above. The extensive dehydration induced by cryoprotective loading makes it difficult to visualize the finer elements of the ultrastructure such as vesicles and microtubules. The overall appearance of tissue in terms of the larger structural elements and their relationship to each other is apparently normal. [Image is courtesy of Brian Wowk, Ph.D., of 21st Century Medicine, Inc., http://www.21cm.com/]

Figure 14: High magnification TEM (~ 40,000x) of vitrified rabbit brain tissue discloses the presence of difficult to visualize fine structures – in this case a synapse (S) with synaptic vesicles visible as dark densities in the synaptic bouton and a small myleinated (M) axon containing condensed axoplasm (A). Importantly, the topographical and structural relation of the synapse to the surrounding structures appears intact. [Image is courtesy of Brian Wowk, Ph.D., of 21st Century Medicine, Inc., http://www.21cm.com/]

Figure 15: TEM of rabbit cerebral cortex white matter (15,000x) subjected to vitrification, rewarming and perfusion fixation using M-22 and the perfusion protocol shown in Figure 10, above. There is severe dehydration of the axoplasm and separation between some of the layers of myelin. There is no evidence of ice formation, and all structural changes appear to be a consequence of CPA-induced dehydration. These changes are reversible with controlled removal of CPA and return of the tissue to incubating medium (see Figure 17, below). [Image is courtesy of Brian Wowk, Ph.D., of 21st Century Medicine, Inc., http://www.21cm.com/]

Figure 16: Mosaic of TEM’s demonstrating continuity of a long axon (red arrows) in a rabbit brain subjected to vitrification, rewarming and perfusion fixation using M-22 and the perfusion protocol shown in Figure 10, above. The tear in the tissue (green arrow) is believed to be a processing artifact. Two capillaries visible near the middle and top of the mosaic (blue arrows). [Image is courtesy of Brian Wowk, Ph.D., of 21st Century Medicine, Inc., http://www.21cm.com/]

As can be seen quite dramatically above, in Figure 16, the axons are intact over long distances within the NVT treated brains. The areas of open space seen in Figure 15 are not due to ice formation, but rather appear to be tears in the brain tissue resulting from the cryoprotectant-induced dehydration. This is a worrisome problem that Alcor-B is actively working to solve. However, it should be emphasized that such damage does not destroy any information about the structure of the brain tissue. Thus, it should be possible to restore the tissue to its pre-cryopreservation state. It is also the case that micro-tears of this nature occur in concussion and other kinds of closed head trauma and that they are survivable, albeit it often with some cognitive impairment, with even the very limited repair abilities the brain naturally possesses.

Figure 17: Hippocampal CA4 cells following recovery from vitrification using a fully reversible, viability conserving technique. Following rewarming and unloading of the CPA the tissue was incubated in artificial cerebrospinal fluid at 35oC for >60 min before being fixed in low-osmolality Karnovsky’s and examined by TEM.[6]

Most reassuringly, when brains subjected to NVT are cleared of cryoprotectant and reperfused with a life-supporting physiological solution, the dehydration induced changes in the fine structure of the brain observed in the NVT- state disappear, as can be seen in Figure 17, above.

Both freezing and vitrification have the potential to disrupt the structures that encode LTM in ways that would leave them non-infer able. Vitrification may do this by the expedient of altering membrane structure irreversibly by dehydration, or by changing the molecular structure of the membranes (or membrane components) by directly perturbing their structure. Vitrification solution is not water, and water is critical to the structure of many of the molecules inside cells. Indeed, a good part of the science behind designing tolerable vitrification solutions is to make them behave as much like water as possible – while at the same time behaving as good, or good enough, glass forming agents when cooled.On a purely structural basis it would seem that vitrification, applied under ideal (laboratory) conditions, is preserving the structures that encode memory and personality. To the extent that structural vitrification (as opposed to fully reversible, viable vitrification) perturbs or damages the biochemistry associated with LTP, there are grounds for concern. However, it seems unlikely that such injury would render the biochemistry of the brain non-infer-able, and therefore nonviable.

Real World Considerations

While laboratory investigations conducted under ideally controlled conditions provide considerable reassurance that existing cryopreservation techniques can conserve the essential structural and biochemical elements that comprise personal identity, such techniques are rarely available to human cryonics patients. Due to medico-legal and logistical constraints, most patients presenting for cryopreservation suffer extensive peri- and post-cardiac arrest global ischemia. When cryoprotection is delivered under these conditions in the laboratory setting, the results are very discouraging.

Figure 18: Feline cerebral cortex frozen, thawed and fixed in the presence of 4 M glycerol after 30 minutes of normothermic ischemia, followed by 24 hours of cold ischemia at ~2-4oC. There was severe disruption of the tissue fine structure by ice (A,B), in addition to changes associated with ischemia such as mitochondrial swelling and blebbing of the endothelial cells (A). [TEMs by the author.][7]

In 1983, studies were undertaken by Alcor-B to determine the effects of 30 minutes of normothermic ischemia followed by 24 hours of cold ischemia at ~ 2-4oC.[101] Healthy adult cats were anesthetized; heparinized and cardiac arrest was induced. The animals were allowed to remain undisturbed on the operating table for 30 minutes, and then were packed completely in water ice, where they were allowed to remain for 24 hours. They were then perfused to 4 M glycerol using a linear increase in glycerol concentration during the ~ 60 minute perfusion interval. Following cryoprotective perfusion, the animals were cooled to dry ice temperature at ~ 3oC/hour, and to liquid nitrogen temperature at ~4oC/hour. Due to the unexpected presence of fracturing in the brain and other viscera, fixative reperfusion following thawing was not possible, and brain tissue samples for TEM were fixed by immersion.

As can be seen in Figure 18, above, there was extensive freezing damage superimposed over ischemic injury to the tissue. The mitochondria were swollen and often showed little internal structure. Neuronal plasma membranes were impossible to identify and the neuropil was macerated by what appeared to be ice artifacts. Large peri-capillary ice holes were almost uniformly present and large islands of tissue had the appearance of a tissue homogenate, as was observed in animals subjected to straight freezing. We thus wish to emphasize that for cryonics patients to obtain the maximum benefit from NVT, they must present for care immediately upon cardiac arrest, so that procedures can be undertaken to minimize the effects of lack of blood circulation on the brain and other vital organs (Figure 19).

The Alcor-B Cryopreservation Procedure

Figure 19: Ideally, immediately following the pronouncement of medico-legal death, circulation and respiration are restored by mechanical means while the patient is rapidly cooled. Medications to protect the brain against damage from lack of blood flow (ischemic injury) are also administered at this time. A new technique for cooling employing chilled liquid perfluorocarbon cycled in and out of the patient’s lungs allows for even faster cooling of the brain (~0.5 oC/min).[8]

Initial Stabilization & Cooling

As shown in Figure 19, above, care of Alcor-B cryonics patients commences the instant that medico-legal death is pronounced. Circulation and respiration are temporarily restored by mechanical means, initially employing chest compressions and mechanical ventilation. Cooling is also initiated at this time; both externally, and by the infusion of cold fluids into the abdominal cavity as well as chilled perfluorochemical into the lungs. Cooling using these technique can approach that achievable with cardiopulmonary bypass (1.0oC/min) for the first 10 minutes of closed-chest cardiopulmonary support.

Figure 20: The Alcor-B extracorporeal membrane oxygenation, or ECMO cart, being used to provide circulation, gas exchange and cooling to a cryonics patient who has experienced medico-legal death in his home, under the care of home hospice.

As soon as possible, usually with 45-90 minutes of the onset of cardiac arrest, circulation and gas exchange are taken over by the use of a blood pump and a membrane oxygenator (extracorporeal membrane oxygenation, or ECMO). ECMO allows any deficits in artificial circulation or ventilation due to organ failure (such as fluid accumulation or tumor in the lungs) to be side-stepped, and it also allows for far more rapid cooling, typically in the range of 1oC/min all the way down to a few degrees above freezing. The Alcor-B ECMO cart is shown in Figure 20, above.

Cryoprotective Perfusion

Figure 21: At left above are the process control refractometrs (inside perspex fronted cabinet) which monitor the concentration of cryoprotectants going into (arterial) and coming out of (venous) the patient. The data stream from these refractometers feeds into the cryoprotective perfusion and cooling control computer. Next to the refractometers are the cryoprotectant addition pump and the recirculating perfusate withdrawal pump. The third pump is for ‘cardiotomy suction’ to recover perfusate leaking into the chest wound and return it to the circuit. At right above is the recirculating and mixing reservoir (yellow top) sitting atop a magnetic stirring table. A magnetically driven stir bar mixes the concentrated cryoprotectant solution with the much more dilute perfusate being recirculated through the patient.

Once the patient has been stabilized and temporarily protected against further ischemic injury, he is transported to Alcor-B’s facilities for cryoprotective treatment and cooling to -150oC for long term care. The introduction of cryoprotectants is carried out using a sophisticated, computer controlled perfusion system developed in-house by Alcor-B. The key elements of the cryoprotectant introduction circuit are shown in Figure 21, above, and in schematic form in Figure 22, below. Two low capacity pumps deliver cryoprotectant to the perfusate being recirculated through the patient, and withdraw fluid from the circuit – fluid containing water from the patient’s tissues – which is discarded.

Figure 22: A schematic diagram of the extracorporeal circuit used to replace ~60% of the water in a cryonics patient’s body with vitrification (cryoprotective) drugs.

The process of cryoprotective perfusion requires very careful control over not just the pressure and the flow rate of the cryoprotective solution through the patient’s circulatory system, but also of the temperature. The toxicity of the cryoprotective drugs is a function of both their concentration and the temperature at which they are introduced. The lower the temperature; the lower the toxicity of the cryoprotective agents. That is why, in order for the rabbit kidney to recover from cryoprotectant loading to a vitrifiable concentration of cryoprotectant, the final phase of introduction must be carried out at -20oC. If this is done, 100% of kidneys treated with a vitrifiable amount of M-22 cryoprotectant will recover completely, and support the animal as the sole kidney after re-implantation.

Figure 23: At left, above, is the controlled temperature enclosure for cryoprotective perfusion of the patient and cooling to -150oC. The contoured aluminum module on which the patient rests is the bottom half of the protective pod that will enclose the patient during long-term cryogenic storage. Once perfusion and deep cooling are complete, the pre-cooled upper half of the patient pod is attached and the patient is transferred to long-term storage. At right, above, is close-up view of the liquid nitrogen (LN2) vapor circulating fans and the LN2 dispensing manifold. A solenoid, under computer control, open and closes the valve to the LN2 reservoir to maintain the temperature at the desired point.

However, as previously noted, it is not yet possible to introduce M-22 into mammalian brains at such a low temperature. Nevertheless, it is still very important to control the temperature precisely and to keep it as low as possible during cryoprotectant loading. The current procedure for perfusing cryonics patients with M22 is to wash out the blood with a specially designed carrier solution called B1, and then continue perfusion with B1 at ~+3.5oC. Over a period of ~90 minutes, a concentrated form of M22 (125%) is gradually added to effect a linear increase in concentration in the perfusion circuit in order to allow the patient’s cells adequate time to equilibrate, and thus avoid injury from too much cellular dehydration.[9]

When 50% of target concentration of M-22 is reached, there is a pause in the addition of M-22 to the circuit, again in order to allow time for cryoprotectant to equilibrate more completely, and also to allow for the patient’s temperature to be reduced to -3oC. When the venous and arterial concentrations of M-22 are roughly equal, the concentration of M-22 is rapidly increased to 100% of the target concentration. This is done in order to minimize the toxic effects of the cryoprotectants that would occur if they were introduced at these (high) concentrations at temperatures at or above 0oC. At this point, the arterial concentration is held between 100% and 105% as long needed, but not exceeding 5 hours, until the concentration of M-22 in the venous perfusate reaches 100% of the target concentration.[9]

Figure 24: Once the patient is connected to the cryoprotective perfusion system and flushed with B1 carrier solution, the control of all parameters of cryoprotective perfusion is assumed by the computer. Arterial and venous pressures, perfusate flow rate, cryoprotectant concentration increase and all temperatures are under computer control. This is necessary because the rapid changes to these parameters that are required to minimize perfusion time and reduce toxicity by keeping the patient’s temperature just above the freezing point of the cryoprotectant-water mixture in his tissues cannot be managed by humans – we’re too slow – and too easily distracted. 

Control over the temperature of the patient, and the perfusate flowing through his circulatory system, is achieved by the use of a sophisticated, computerized temperature controlled enclosure, in addition to the computerized perfusion system already described. This enclosure was developed by Alcor-B, and is shown in Figure 23, above. The refrigerated enclosure is cooled by liquid nitrogen vapor and it can maintain the patient’s temperature at any desired point between +15oC and -150oC. This means that when cryoprotective perfusion is completed, the patient can be cooled, in place within the enclosure he was perfused in, all the way to his long-term storage temperature of -150oC. The entire perfusion and cooling to storage procedure are completely automated and continuously monitored by Alcor-B’s highly trained cryo-biomedical staff (Figure 24).

Long-Term Cryogenic Care

Figure 25: Long-term cryogenic storage is carried out using a newly developed technology known as intermediate temperature storage (ITS). ITS holds the patient at a temperature of ~ -150oC, which is a sufficiently low temperature to stop all biochemical activity, and yet not so cold that it could cause fracturing in the patient’s tissues.

Once the patient has been cooled to storage the temperature, the other half of the protective aluminum storage pod, which has been pre-cooled to -180 oC, is placed atop the bottom half of the pod that the patient has rested upon during cryoprotective perfusion and cooling. With the two halves of the pod secured, the patient is them removed to long-term storage in one of Alcor-B’s unique, Intermediate Temperature Storage (ITS) units (Figure 25). There the patient can be held at -150oC for centuries, if need be, to await rescue by more sophisticated medical technology. And in the meantime, Alcor-B will be there to care for him, and to assist in developing both the social and the technological infrastructure required to restore him to life, health and youth

Validating NVT in Cryonics Patients

Figure 26: Quality control and validation of our procedures is critically important to Alcor-B. For that reason we treat each human case as an experiment; an undertaking to be carefully documented and to be learned from. At left above is an Alcor-B patient following cooling to -150oC. The chalky white areas present on the skin are areas where ice formation has occurred. The rest of the patient’s skin appears somewhat translucent and is not frozen, but rather is vitrified – converted into a glassy state. At right is a section of spinal cord taken from an Alcor-B neuropatient (i.e., a head-only patient). This section of cord is completely free of ice and demonstrated normal ultrastructure for tissue subjected to NVT, as can be seen in Figure 28, below.

Alcor-B is not content to rely solely on animal experiments conducted under ideal laboratory conditions; we have carried out careful examinations of patients undergoing NVT both during cooling, and after 8 months of storage, in order to evaluate the amount of superficial freezing that is occurring. As can be seen at left in Figure 26, above, there is always some ice formation in the skin of NVT patients, which is typically associated with peri-cardiac arrest trauma, or with injury to the skin secondary to the placement of temperature probes and the creation of “monitoring widows” in the skull. This ice formation is not of concern, and the amount of ice formed in the skin is within survivable limits for that tissue.

Figure 27: At left above is a dog treated with NVT under ideal conditions of 5 minutes of cardiac arrest at normal body temperature followed by 45 minutes and closed-chest CPS and then extracorporeal cooling to 10 oC. Cryoprotective perfusion was then carried out followed by cooling to -150oC and solidification. There is no visible ice and the animal presents the appearance of being uniformly equilibrated with cryoprotective solution. At right, above, is a dog which experienced cardiac arrest followed by cooling with ice bags. Blood washout and cryoprotective perfusion were not initiated until 18 hours after the start of both cardiac arrest and external cooling. This animal underwent freezing and the distribution of cryoprotective agents was very inhomogeneous in the brain and in the skeletal muscle and other tissues.

We have conducted many experiments simulating the non-ideal conditions to which cryonics patients are sometimes subjected and we have also taken non-vital samples from human patients in our care that have been treated under a variety of conditions, ranging from optimum, to highly undesirable (Figure 27). In patients treated under ideal conditions, with only a few minutes of ischemia between the time of cardiac arrest (and the pronouncement of legal death) and the start of the procedure, the spinal cord is uniformly vitrified, as is evident in at right in Figure 26, above. TEM examination of tissue taken from patients treated under such conditions is indistinguishable in appearance from that observed in experimental animals (dogs) subjected NVT (Figure 28). Examination of the surface of the brain through the two observation windows (burr holes) made in the skull at the start of the procedure also show no evidence of ice formation when a patient is treated with NVT under ideal conditions.

Figure 28: Above are gray (left) and white (right) matter from the spinal cord of an Alcor-B neuropatient who underwent NVT under optimum conditions. The gray matter (left) shows two normal appearing capillaries and dehydrated, but otherwise normal fine structure. The white matter (right) shows more dehydration from cryoprotection. The interiors of the axons (axoplasm) are shrunken and the myelin sheaths that surround the axons have a rumpled and somewhat unraveled appearance.  Alcor-B is currently conducting research to try to overcome these problems. Despite these admittedly undesirable alterations, the overall structure of the spinal cord appears beautifully preserved.

Summary

Figure 29: Patients treated with NVT & ITS may be recoverable before this century’s end using biologically derived organogenesis and tissue repair technologies. This offers considerable risk reduction and improved odds that cryopreservation will be successful.

With the advent of NVT and ITS technology, Alcor-B is now able to cryopreserve patients in a state of near viability, with little structural injury. It is conceivable that patients so treated may be recoverable before this century’s end, if the pace of biomedical advance continues at the rate that it has over the past five decades. The ability to recover cryonics patients within the limits of normal corporate and human undertakings (i.e., 60 to 90 years) offers a tremendous reduction in the degree of risk to which the patients are subjected. For example, very few business entities of any kind survive long-term. Even non-profit organizations (NPOs), such as Alcor-B, have a ~95% failure rate by the 30 year mark, and of those that survive to 30 years, only ~1 % will survive to 100 years.

Figure 30: Using the “Cryonics Calculator” developed by Brook Norton (http://www.cryonicscalculator.com/), and assuming a very conservative risk of organizational failure of 30% for the first two decades of cryopreservation, 75% for the second 20 year interval, 10% for the third 20 year interval, 3% for the fourth 20 year interval and 2% for last 20 year interval the probability of being recovered from cryopreservation is only 17%. [This assumes that you are currently 50 years old and will be cryopreserved at age 90 and that you have a 5% risk of autopsy, or other catastrophic destruction of your remains prior to cryopreservation.]

 Using a very simple model of the impact of institutional failure on the chances of recovery from cryopreservation, and (approximately) applying the historical NPO failure rate, the chances that a person will be recovered from cryopreservation over a 100 year period of storage are only 8%. This outcome does not consider other risks, such as government proscription of cryonics, or existential risks, such as fire, flood, earthquake, pandemic disease, etc. Very importantly, it also does not take into account the probability that existing cryopreservation procedures may not be sufficiently advanced to allow for recovery of today’s patients (the default assigned autopsy risk is 5%, which is also quite low). Given such a high probability of failure solely from lack of institutional continuity, it should be clear why so many people, especially those who are knowledgeable and world-wise, fail to find cryonics sufficiently attractive to commit to it personally.

Figure 31: Alcor-B’s timeline to achieving fully reversible suspended animation for both the human brain and the intact human.

This is one of the principal reasons that Alcor-B is working so hard to improve the quality of cryopreservation, and to ultimately achieve fully reversible suspended animation. While the current odds of cryonics working are anything but good, we strongly believe that we can change that situation. With our commitment to research to achieve suspended animation, and our deep commitment to achieve truly long-term institutional stability, we believe cryonics will become an increasingly attractive choice. We invite you to join us in our effort to break the limiting chains of time and open a future for all of humanity that is as potentially limitless in time, as it is boundless in space.

References

1.            Deutsch D: The Fabric of Reality: The Science of Parallel Universes and Its Implications New York: Penguin; 1998.

2.            Tegmark M: Paralell Universes: http://space.mit.edu/home/tegmark/PDF/multiverse_sciam.pdf. Scientific American 2003(May, 2003):41-51.

3.            http://www.sciencedaily.com/releases/2009/12/091210092005.htm. Science Daily 2009.

4.            Darwin M, Russell, S, Wakfer, P, Wood, L, Wood, C.: Effect of a human cryopreservation protocol on the ultrastructure of the canine brain. (Originally published by BioPreservation, Inc, as BPI Tech Brief 16 on CryoNet and SciCryonics, May 31, 1995), http://wwwalcororg/Library/html/braincryopreservation2html and http://wwwalcororg/Library/html/braincryopreservation1html 1995.

5.            Fahy G, Wowk, B, Pagotan, R, et al.: Physical and biological aspects of renal vitrification. Organogenesis 2009, 5(3):167-175.

6.            Pichugin Y, Fahy, GM, Morin, R.: Cryopreservation of rat hippocampal slices by vitrification. Cryobiology 2006, 52(2):228-240.

7.            Darwin M, Leaf, JD.: Cryoprotective perfusion and freezing of the ischemic and nonischemic cat: http://www.cryonet.org/cgi-bin/dsp.cgi?msg=1389, http://www.cryonet.org/cgi-bin/dsp.cgi?msg=1390, http://www.cryonet.org/cgi-bin/dsp.cgi?msg=1391, http://www.cryonet.org/cgi-bin/dsp.cgi?msg=1392  See also: Federowicz,  MG. and Leaf JD. Cryonics. issue 30, p.14,1983. 1983.

8.            Darwin M, Russell, S, Rasch, C, O’Farrell, J, Harris, S.: A novel method of rapidly inducing or treating hypothermia or hyperpyrexia, by means of ‘mixed-mode’ (gas and liquid) ventilation using perfluorochemicals. In: In: Society of Critical Care Medicine 28th Educational and Scientific Symposium. vol. 27. San Francisco: Critical Care Medicine; 1999: A81.

9.            de Wolf A: Vitrification agents in cryonics: http://www.depressedmetabolism.com/2008/07/08/vitrification-agents-in-cryonics-m22/. 2008.

 Selected Bibliography

  1. Fahy GM, Wowk B, Wu J, Phan J, Rasch C, Chang A, Zendejas E. Cryopreservation of organs by vitrification: perspectives and recent advances. Cryobiology, 2004 Apr;48(2):157-78.
  2. Fahy GM, Wowk B, Pagotan R, Chang A, Phan J, Thomson B, Phan L. Physical and biological aspects of renal vitrification. Organogenesis. 2009 Jul-Sep;5(3):167-75.
  3. Fahy, G.M. “A personal view of the Alcor research fund-raiser.” Cryonics, Volume 12, December 1991, Issue 137, pp. 13-14.
  4. Fahy GM, Wowk B, Wu J, Paynter S. Improved vitrification solutions based on the predictability of vitrification solution toxicity. Cryobiology, 2004 Feb;48(1):22-35.
  5. Wowk B, Leitl E, Rasch CM, Mesbah-Karimi N, Harris SB, Fahy GM. Vitrification enhancement by synthetic ice blocking agents. Cryobiology. 2000 May;40(3):228-36.
  6. Wowk B. Anomalous high activity of a subfraction of polyvinyl alcohol ice blocker. Cryobiology. 2005 Jun;50(3):325-31.
  7. Gomez-Angelats M, Cidlowski JA. Cell volume control and signal transduction in apoptosis. Toxicologic Pathology. 2002 Sep-Oct;30(5):541-51.
  8. Schliess F, Haussinger D. The cellular hydration state: a critical determinant for cell death and survival. Biological Chemistry. 2002 Mar-Apr;383(3-4):577-83.
  9. de Wolf, A. de Wolf, C. Advances in Cryonics Protocols, 1990-2006: http://www.alcor.org/Library/html/protocoladvances.html
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You be the Judge: Understanding and Evaluating the Quality of Human Cryopreservations from Cryonics Organization Literature and Case Report Data, Part 4 http://chronopause.com/index.php/2011/04/11/you-be-the-judge-understanding-and-evaluating-the-quality-of-human-cryopreservations-from-cryonics-organization-literature-and-case-report-data-part-4/ http://chronopause.com/index.php/2011/04/11/you-be-the-judge-understanding-and-evaluating-the-quality-of-human-cryopreservations-from-cryonics-organization-literature-and-case-report-data-part-4/#comments Mon, 11 Apr 2011 11:42:17 +0000 admin http://chronopause.com/?p=600 Continue reading ]]> Medical Records, Medical History and the Necessity for Highly Skilled Cryonics-Based Medical Evaluation and Judgment

“The physician must be able to tell the antecedents, know the present, and foretell the future–must mediate these things, and have two special objects in view with regard to diseases, mainly to do good or to do no harm.”[119]

-Hippocrates Of The Epidemics

By Mike Darwin

Figure 9: Hippocrates of Kos, the father of rational medicine.

In the past two decades I have had the frustrating experience of having no fewer than four Officers, Directors or Presidents of currently extant cryonics organizations dismiss the need to gather and thoroughly analyze the medical records and the medical histories of cryopatients. Two cryonics organization Presidents have informed me that these materials are not only hard to gather, but in addition, are of little or no use to the patient, since future medical diagnostic and treatment modalities will render such information superfluous at best, and misleading at worst. As a consequence, it has been deemed not merely annoying and futile to gather this information (let alone analyze it), but also a needless and costly burden on the cryonics organization, and one which is presumably best avoided.

My purpose here, from the beginning, will be not only to refute this erroneous position, but to demonstrate, largely by example from long previously published case reports, the criticality of the patient’s medical condition prior to as well as at the time he presents for cryonics care, to the quality of the cryopreservation he will subsequently receive. In addition, I wish to demonstrate that the routine acquisition and interpretation patient medical records is not just of great utility to the patient for whom it is done, it stands to benefit all patients who come later, by enriching the knowledge and experience base in the practice of cryonics as a scientific-technological discipline.

Example 1: Pre-cryopreservation Disease May Alter Critical Anatomy

The first example I am going to use to demonstrate the criticality of the patient’s medical history (Hx) and complete medical record to optimizing cryopreservation and avoiding delay took place on 12 Feb 1985. Since the involved family member discussed in this case is now in cryopreservation, it is possible to discuss the case with greater frankness than was possible when it was first reported. The patient was a 68-year-old woman (Alcor Life Extension Foundation patient A-1068) who was terminally ill with recurrent, disseminated lymphoma. The husband was not only supportive of cryonics; he was a long-time cryonicist himself. Hospital cooperation was excellent and cardiopulmonary support (CPS) was initiated within ~1-2 min of cardiorespiratory arrest and pronouncement. The patient was transported from the hospital to a nearby mortuary without any interruption in CPS and a right femoral cut-down was undertaken (with CPS still underway) to allow for femoral arterial and venous cannulation to permit femoral-femoral cardiopulmonary bypass (CPB) and total body washout.  I will now quote directly from the case report as it appeared in Cryonics magazine in April of 1985:

“The patient’s right groin was prepared for surgery by swabbing with Betadine solution and draping with sterile towels and a fenestrated drape. The anatomical position of the right femoral artery and vein were located by reference to the pubic tubercle and the anterior superior iliac spine. An incision with a #10 scalpel blade was made at the midpoint between these two structures, beginning at the inguinal ligament and running parallel to the longitudinal axis of the leg for approximately 5 cm.

The femoral artery was promptly identified and an 18 fr. arterial cannula, USCI type 1860, introduced through an arteriotomy and secured with silk ties. Despite extensive dissection which consumed nearly an hour, the right femoral vein could not be located. It was later discovered from the patient’s medical records (which were unavailable at the time of transport) that the patient had a history of thrombophlebitis with a venogram done in December, 1975 demonstrating extreme deep vein thrombosis of the right leg, including the entire right femoral vein.

Owing to lack of success identifying the right femoral vein, the left groin was prepared for surgery and the left femoral vein was promptly raised and cannulated with a 32 fr. venous cannula, USCI type 1967.” http://www.cryonics.com/Library/html/casereport8504.html

The delay, due to our inability to find a non-existent femoral vessel under very difficult field conditions (the wound rapidly filled with blood-tinged interstitial fluid), occurred because the patient was massively edematous due to hepatorenal syndrome (liver and kidney failure) and fluid resuscitation (~20 L of IV crystalloid), compounded by the necessity to make a contralateral wound and raise the left femoral vein, was approximately ~ 30-45 minutes. While the patient was receiving closed chest CPS, such support (using the conventional CPR technique available at the time) was only marginally effective, and was further compromised by the presence of fulminating pulmonary edema, which greatly reduced the ability of the lungs to provide gas exchange.

Figure 10: Femoral-femoral cardiopulmonary bypass (CBP) requires the placement of a long, large caliber cannula through the femoral vein (A&B) and into the inferior vena cava, preferably threaded up to the level of the right atrium (C). If the femoral vein has been obliterated, sclerosed, or is otherwise too small to accommodate the venous cannula (E), then either the contralateral femoral vein must be used, or venous drainage may be accomplished by cannulation of the internal jugular vein in the neck (not shown).When the femoral vein is destroyed as a result of disease or trauma, it is ‘replaced’ by a network of smaller caliber collateral vessels which serve to provide venous return from the leg to the heart (D). These vessels are often tortuous, are not of sufficient diameter to accommodate the venous cannula, and do not provide a straight, large diameter path to the inferior vena cava. In the case of patient A-1086 the arterial cannula in place in the right groin was used for perfusion (E) and the venous return cannula was placed in the left femoral vein.

The patient’s husband was, at his and the patient’s request, present during the entire procedure, and he was able to inform us, as we struggled futilely to identify the right femoral vein in the massively edematous tissue, that his wife had suffered severe deep vein thrombophlebitis of the right leg, six years earlier, in 1975. This was, in fact, the reason for our inability to identify and raise the right femoral vein; it no longer existed. Our only choices in this situation were either to cut-down, raise and cannulate the femoral vein in the opposite leg, or to cannulate the internal jugular vein in the neck. Because we needed to maintain the patency of the jugular veins for drainage during CPA perfusion, we chose to surgerize the contralateral leg and cannulate the opposing femoral vein to accomplish venous drainage for CPB.

When the patient’s body was subsequently autopsied (she was a neuropatient) we found a narrow band of tissue tightly adherent to the fascia of the femoral sheath, which was all that remained of the femoral vein. What made this incident particularly difficult for all involved, was that both Jerry Leaf and I had repeatedly made efforts in the months preceding the patient’s arrest to obtain her medical records – efforts which were unsuccessful. The patient’s husband was a highly intelligent man, and he immediately understood the implications of his inaction in obtaining the patient’s medical records prior to her cryopreservation. His wife had suffered an additional ischemic insult that was completely avoidable and we missed the last plane back to Alcor by less than hour, exposing the patient to ~ 8 hours of additional cold ischemic injury as a consequence.

Example 2: Pre-Cryopreservation Pathology may Preclude or Delay Adequate Cryoprotective Agent Equilibration in the Brain without Effective Intervention

In clinical medicine, the patient’s medical history is defined as a written summary of past and present medical conditions which may contain clues bearing on their health; past, present, and future. The medical history is thus an account of all medical events and problems a person has experienced (including psychiatric illness), and it is especially helpful when a differential diagnosis is needed. By contrast, the patient’s medical record is a chronological written account of a patient’s examination and treatment that includes the patient’s medical history and complaints, the physician’s physical findings, the results of diagnostic tests (including copies of any medical imaging performed), procedures, medications and therapeutic interventions. In short, the patient’s medical record ideally contains not only all of the conclusions and summaries of a patient’s illnesses, preventative care and treatment, but also all of the raw data upon which those actions and conclusions were based.

Figure 11: The anatomy of a heartbeat. The heart’s pacemaker is the sinoatrial (SA) node, which sends impulses to the atria and to the atrioventricular (AV) node,  from which they are relayed to the ventricles. The signal from SA node (1) is seen as the P-wave on the ECG, at right. This signal results in the contraction of the atria, and within milliseconds it reaches the AV node (2), which in turn signals the rest of the cardiac conduction system to initiate ventricular contraction (3, 4, 5). The QRS complex of the ECG reflects the rapid depolarization and contraction of the right and left ventricles. Since the ventricular muscle mass is large, the amplitude of the electrical signal generated is on the ECG is corresponding large, as well.

For example, a cardiologist in 1998 may have correctly concluded, based upon a 12-lead electrocardiogram (ECG), that a patient suffered a serious myocardial infarction (MI) of the posterior wall of the left ventricle, with evidence of a previous infarction of the left anterior descending coronary artery. However, at that time, sophisticated algorithms for analysis of the ECG were not in common use that would, for instance, allow for evaluation of subtle variations in R-R regularity of the ECG following an MI.[120, 121] While the elapsed time (interval) between R waves in the ECG appears superficially regular, careful analysis reveals that it is in fact variable, and obeys the laws of chaos theory.[122] Children show complexity and fractal correlation properties of the R-R interval time series comparable to those of young adults, whereas healthy older people demonstrate R-R interval dynamics showing higher regularity and altered fractal scaling that are consistent with a loss of complex variability.[123]

Figure 12: Loss of chaotic variability and accompanying increase of the R-R interval is a sign of damage to the cardiac conduction system which is prognostic of a markedly increased risk of sudden cardiac arrest (SCA).Simplification of the fractal complexity of the R-R interval occurs in normal aging, independent of frank cardiac disease, and may be responsible for some of the increased risk of SCA associated even with so-called “healthy aging.” Loss of R-R interval fractal complexity in the presence of cardiac disease, or during the agonal process in slowly dying patients, is prognostic of increased risk of cardiac arrest, or impending cardiac arrest in the agonal patient.

This phenomenon is very pronounced in patients who have suffered MIs, or other cardiac damage that destroys or degrades the robustness (complexity) of the system of nerves that conducts the contractile impulses to the various parts of the heart (the cardiac conduction system). As the conduction system is pruned down by age and/or disease, there are fewer and fewer signal pathways for the Q-wave, the impulse that initiates heart beat, to travel through and to reach the myocardium. Thus, paradoxically, the more uniform the R-R interval becomes and the less chaotic variation it exhibits, the greater the patient’s chances of experiencing sudden cardiac arrest.[120] [A good summary of this phenomenon and its prognostic utility in heart disease is http://circ.ahajournals.org/cgi/reprint/101/1/47] The take home messages here are that the data are only as good as the theory and technology for interpreting them, and that a physician’s summary of raw data, no matter his competence, will, in many instances, be incomplete and sometimes inaccurate, or in any event, lacking the context necessary to yield the maximum benefit for the cryonics patient.

The following case illustrates not only the importance of gathering and evaluating the patient’s medical records, but also the importance of being able to meaningfully interpret the medical history and medical records data in the context of cryonics. I will open this particular analysis by quoting from the case report of Alcor patient A-2063:

“The initial contact for this March 2004 case began at 12:15 (MST), with Hugh Hixon taking the emergency call. A non-member was in the hospital and dying. The gentleman was suffering from terminal cancer and had a subdural hematoma, the result of recent brain surgery. He was suffering from sepsis and pneumonia when Alcor received the call…”

Among the myriad deficiencies in this case report is that virtually no details are given about the patient’s medical Hx, including the patient’s age, sex, weight, race, fat cover, body surface area, underlying medical condition, and so on. However, in this case, because the date and place of medico-legal death are given, it is possible to infer who this patient was, and thus determine that he was a 36 year old, Caucasian male who suffered from acute myelogenous leukemia and whose proximate cause of cardiac arrest was sepsis and thrombocytopenia (inadequate number of circulating blood platelets) following a bone marrow transplant. The thrombocytopenia thus explains the intracranial bleed in the form of a subdural hematoma.

The case report continues as follows (emphasis mine):

Neuro-perfusion was begun at 09:00, after the head was removed and placed inside the cephalon enclosure. We saw good flow from the left side, but the right jugular showed little venous return. Flow eventually picked up somewhat, but the reason for the obstruction was not determined. Less than twenty minutes later, we noted some swelling of the brain. We attempted to moderate the swelling by slowing perfusion and allowing more time for the cryoprotectant to equilibrate across the hemispheres. The left hemisphere reached terminal concentrations at 15:00, but the right hemisphere had only obtained 59.4% of the concentration needed to vitrify. We continued the neuro perfusion for another five hours before stopping because of toxicity concerns, lowered uptake curves, and staff exhaustion. Final uptake concentration on the left jugular side was 117% of the concentration necessary to vitrify, and the concentration on the right had climbed to 74%. This was the longest neuro-perfusion we’ve ever done.

Figure 13: At the top are images of a human brain in the presence of a right subdural hematoma. At left is the brain at autopsy (after fixation and sectioning) showing compression of the right hemisphere and the relative collapse of the right cerebral ventricle and at right is a CT scan with false color (red) showing the appearance of a typical subdural bleed prior to craniotomy to evacuate the accumulated clotted and fluid blood overlying the brain. The rest of the Figure shows the procedure used for surgical management of a subdural hematoma; beginning with an incision in the skin (1) to expose the cranial vault over the area of the hematoma, after which the bone is cut and temporarily removed to expose the dura mater, the fibrous, tough membrane that covers the cerebral hemispheres (2). The dura is then incised and reflected to allow the surgeon to evacuate the hematoma; a process that is usually carried out by gentle suction and saline irrigation of the affected area of the cortical surface (3). Any evident bleeding vessels are clipped and cauterized, the bone flap is replaced and secured in position with metal staples or stainless steel sutures, and the skin flap is reapproximated and (typically) closed with metal staples (4).

It is of great importance to note that two physicians were either in consultation, or directly involved in this patient’s care; one of them a Board Certified neurosurgeon. This is both noteworthy and remarkable, when consideration is given to the sentences highlighted in red in the excerpt from the case report, quoted above. We are also told that, “Burr hole drilling was started within five minutes, after shaving the head and disinfecting the scalp, and was completed by 07:29.” While we are not told which side of the patient’s brain the subdural bleed was on, but we are told, “We saw good flow from the left side, but the right jugular showed little venous return. Flow eventually picked up somewhat, but the reason for the obstruction was not determined.” and that likely answers the question for us (the right hemisphere).

A quick glance at Figure 13, above, should also go a long way towards explaining why the “right jugular showed little venous return” at the start of cryoprotective perfusion, and also why cerebral edema developed in this patient. The brain receives ~ 1/3 rd of the resting cardiac output and the internal jugular venous drainage from an isolated cephalon will consist mostly of return from the cerebral hemisphere it drains. A patient presenting for cryopreservation with this medical Hx should be re-imaged during the agonal period and must, before the start of CPA perfusion, have the craniotomy re-opened to ensure there has been no subdural rebleed, accumulation of serosanguineous fluid, or pre-existing cerebral edema that could compromise CPA equilibration in the brain. In this case, none of these things were done.

The case report further notes that, “The left hemisphere reached terminal concentrations at 15:00, but the right hemisphere had only obtained 59.4% of the concentration needed to vitrify. We continued the neuro perfusion for another five hours before stopping because of toxicity concerns, lowered uptake curves, and staff exhaustion. Final uptake concentration on the left jugular side was 117% of the concentration necessary to vitrify, and the concentration on the right had climbed to 74%. This was the longest neuro-perfusion we’ve ever done.”  If we do the math, that works out to this patient being exposed to ~ 1-8 M cryoprotectant solution for 11 hours, presumably at a temperature of somewhere between +5 to -3oC, the temperatures Alcor has reportedly used in the past to equilibrate patients with the vitrification solutions B2C and M-22, which it licenses from 21st Century Medicine.

Figure 14: The graph at top shows a 191 minute (3 hr, 11 min) cryoprotective perfusion for the vitrification of Alcor Life Extension Foundation neuropatient A-1097,carried out at the in January of 2006. The vitrification solution employed was M-22, however no patient temperatures during cryoprotectant loading are given in the case report. The graph below shows a 255 minute (4 hr, 15 min) cryoprotective loading of Alcor neuropatient A-2024 with a vitrification solution carried out in April of 2005. The solution used and the temperatures it was perfused at were not disclosed in the case report.

The graphs in Figure 14, above, show typical CPA loading times and curves for two Alcor neuropatients. Frustratingly, neither the graphs or the case reports provide patient temperature data during CPA loading, nor do they provide graphic or tabular data that would allow determination of the mean arterial pressure (MAP) over the course of CPA perfusion.  No graphic data for CPA perfusion were given in the case report for A-2036, however, to appreciate the difference in exposure time it is only necessary to multiple 11 hours x 60 minutes to understand that this patient’s CPA perfusion went for 666 minutes; 475 minutes longer than that of patient A-1097 and 411 minutes longer than for that of patient A-2024.

Why did this happen? The answer to that question is present in the patient’s medical Hx, and would have been glaringly evident in the CT and/or MRI scans that no doubt comprised part of the patient’s most recent medical record; principally that he had a large compressive mass of fluid or clotted blood overlying some portion of his right cerebral hemisphere. There are two inevitable and easily foreseeable consequences of this in the context of cryoprotective perfusion. The first is that the clot or fluid mass is not vascularized; it is not permeated by countless capillaries, as is normal brain tissue, with many square centimeters of surface area across which mass transport of CPAs and water can occur. In other words, it is largely ‘dead space’ from which mass exchange can occur only at the surfaces that abut circulated tissues. The second is that such a mass, if it is compressing the brain that underlies it, will reduce or altogether stop flow in the affected cerebral hemisphere. And since cryoprotectant solution is not blood, and does not contain platelets or any other hemostatic agent, any perfusate that leaks from torn or leaking bridging veins on the dura mater, as well as from the pia mater covering the brain, will continue to accumulate in the subdural space, further increasing the intracranial pressure.

In fact, this patient was fortunate that he experienced any cerebral perfusion, because such massive unilateral failure of perfusion of one hemisphere in the presence of a closed cranium is often associated with failure of global brain perfusion, due to elevation of the intracranial pressure to 40–50 mm Hg, which is the range of pressures at which cerebral perfusion, even with severe compensatory hypertension (~250-300 mm Hg), fails.[124, 125] The CPA perfusion pressures used on A-2036 are also not given in the case report, and the patient’s intracranial pressure was either not monitored, or not reported, if it was.

Figure 15: The temperature controlled neuro-cryoprotective perfusion enclosure used by the Alcor Life Extension Foundation. The cephalon is held in position using a standard surgical head fixation halo, with the stump of the neck being positioned over a polycarbonate plastic tray  (venous sump, green arrow) that serves as the reservoir to collect venous drainage from the stump of the neck (right angle blue arrow) and return it to the extracorporeal circuit.

The proper management of this patient would have been to re-open the craniotomy prior to CPA perfusion and to leave it open for the duration of perfusion.[126-128] This would have eliminated the need for a burr hole (and the associated loss of time experienced in creating it) on the affected side, and it would have allowed for free drainage of any leaking perfusate into the venous sump of the neuroenclosure, where it would have been picked up along with the rest of the venous drainage from the jugulars (and the stump of the patient’s neck), been filtered, and then have been returned to the extracorporeal circuit (Figure 15). In addition, the large opening in the skull would have functioned as a decompressive craniotomy, allowing the ischemia-injured brain to swell during CPA perfusion, without the danger of it raising the intracranial pressure (in the closed cranial vault), thus compromising perfusion to the left hemisphere of the brain, as well.

Why didn’t the “cryonics” physicians, one of them a skilled neurosurgeon, who were attending/consulting for this patient, undertake or suggest this course of action? Many answers to this question are possible, some of them decidedly unflattering, however the most likely reasons are as follows:

1) They do not understand the basic principles and practice of human cryopreservation. They very likely did not give consideration to both why and how CPA perfusion works. Unless the physician understands that effective cryoprotection for vitrification can only be achieved by substituting ~ 60% of the water in the patient’s brain tissue with cryoprotectant molecules (that are on average 1/3rd to ½ the molecular weight of glucose!), and which can only be equilibrated via a patent brain tissue capillary bed, the presence of a compressive mass of non-vascular fluid will have no importance to them.

Figure 16: The Bentley Autotransfuser, which made its debut in 1970, allowed emergency medicine physicians and trauma surgeons to recover hemorrhaged blood and rapidly return it to the patient, thus preventing death from exsanguination, and often the need for extensive homologous blood transfusion, as well.

2) In a clinical setting it is essential to secure hemostasis in a surgical wound – any surgical wound – before concluding surgery. Otherwise, the patient will bleed to death, or the wound will become engorged with a pressurized mass of blood (a hematoma) and will subsequently dehisce, or otherwise fail to heal properly. Conventional neurosurgeons do not have the luxury of leaving an open head wound to bleed freely into a catch basin, whereupon the contents are filtered and returned to the venous circulation. However, patients undergoing cryopreservation do have that option, and so do anticoagulated patients undergoing open heart surgery. In the latter case, the blood seeping from and into the sternotomy wound is collected via cardiotomy suction, filtered, and returned to the patient’s circulation. Taking a leaf from the cardiothoracic surgeons, trauma surgeons adapted the cardiotomy suction system in the 1970s and developed auto-transfusion systems (Figure 16) to allow for rapid recovery, reprocessing and reinfusion of a patient’s own shed blood until hemostasis could be secured.[129, 130]

3) They have not been instructed and mentored to care for the cryonics patient as they would any living human being whose medical care they undertook. It is not a precondition that physicians, or other medical professionals (or even volunteers) involved in delivering care to cryopatients, be card carrying (or tag wearing) cryonicists, but it is essential that they understand and share the values of cryonicists, and that they both understand and agree to provide the same level and quality of care that they render to any of their ‘conventional’ medical patients. This knowledge and consent can only be had by a carefully structured course of learning, which actively selects for those men and women capable of such behavior, and which filters out and rejects those who are not. In this respect, such a program of ‘cryomedical residency’ is no different than any other in medicine, in the professions, or in the trades (where the apprenticeship system is used to the same end).

Figure 17: Typical CT images of non-traumatic subdural hematomas (left and center) similar in nature to those frequently seen in spontaneous intracranial bleeds due to thrombocytopenia. The red arrows denote the area of the bleeds, the orange arrows the distortion of the contralateral cerebral ventricles. The green arrow on the image at right shows an air-fluid interface in the left fronto-parietal subdural hematoma cavity with fluid level from burr hole drainage causing mass effect compression the adjacent lateral ventricle (this image was from a case of subdural hematoma secondary to traumatic brain injury). Rebound of the compressed cerebral cortex to normal volume following craniotomy may take several days, providing the patient survives.

Figure 18: The operating rooms of every cryonics facility the author has had responsibility for over the course of his career all featured an x-ray view box (red arrows) to allow for intra-operative viewing and evaluation of diagnostic electromagnetic patient images. The operating rooms of all currently operational cryonics facilities lack this feature; this has been the case since they were first put into operation. Alcor Foundation, 1989 (A), BioPreservation/PW Biomedical, 1992 (B), BioPreservation, 1993 (C), BioPreservation/21st Century Medicine, 1999 (D).

The bottom line is that patient A-2036 suffered ~5-7 hours of unnecessary and undoubtedly injurious cryoprotective perfusion (and the associated additional cold ischemia) when a procedure as simple as removing freshly placed staples, and opening an already created surgical wound, would have very likely reduced or eliminated the problem. This happened primarily because of a lack of the ability to meaningfully interpret the patient’s medical history and current medical condition, and possibly to a lesser extent, because the patient’s medical records, and the medical images that were no doubt present in them, were not reviewed at any point prior to undertaking the patient’s cryonics care. It would be hard to imagine that any thoughtful consideration of an image, such as any one of those shown in Figure 17, above, undertaken in the operating room where CPA perfusion was to take place (before the procedure began) on an inexpensive x-ray viewing box (Figure 18) would not have lead to at least some consideration (and thus understanding of the likely consequences of) lesions of this size and location by anyone with any material degree of medical sophistication, coupled with the barest knowledge of the mechanics of cryoprotective perfusion.

Example 3: Pre-Cryopreservation Disease Often Critically Alters Physiology

Figure 19: Femoral-femoral bypass in cryopatients is typically carried out by placing a short cannula in the femoral artery, and advancing a long, large diameter cannula through the femoral vein, and into the inferior vena cava (IVC). If the intra-abdominal pressure is elevated due to ascites or edema of the visceral organs (abdominal compartment syndrome), it becomes impossible to obtain adequate venous return, because of compression of the IVC. In the case of ascites, the abdomen may be decompressed by the simple expedient of draining it via a stab wound and a fenestrated tube, as shown in the drawing at the upper left.

When blood washout and extracorporeal support are performed in the field, it is necessary to access the circulatory system by cannulating the femoral artery and vein in the groin. When cardiopulmonary bypass (CPB) is carried out in this fashion, the blood flows through the blood vessels in a retrograde fashion – in other words, in the opposite direction from which it normally flows.

Because the blood being pumped from the circuit into the patient is being pumped under pressure into the femoral artery, a short cannula of modest diameter may be used. However, the venous blood, flowing from the body and into the bypass circuit, is flowing at very low pressure, typically at 5-10 mm Hg, and its flow into the circuit reservoir is due to gravity.

As a result, a larger diameter cannula which is much longer, must be used. Ideally, we would like to position the tip of that cannula at the level of the right heart (Figure 12), where the blue arrow is on the schematic in Figure 19, above.[131, 132] However, that is usually not possible to do in the field without x-ray (fluoroscopic) or ultrasound imaging. Thus, the cannula tip is usually in the inferior vena cava (IVC), somewhere below the level of the diaphragm, where the white arrow is pointing in Figure 19.[133] This barely allows for enough venous blood flow out of the patient – even under the best conditions.[134, 135]

If the patient has a large volume of fluid in his abdomen (a condition called ascites), has pre-existing edema of the abdominal viscera, or is very obese, what happens is that the pressure from the excess fluid, fat, or edematous bowel compresses the thin, flexible and essentially unpressurized walls of the vena cava, and prevents adequate venous return.

Figure 20: Shown at left above is the fluid distended abdomen of a patient with severe ascites secondary to end-stage liver failure. The protein-rich ascitic fluid ‘weeps’ from the serosa of the liver and accumulates in the abdomen where it compresses the abdominal viscera and can impede venous return from the lower extremities. At right is a CT scan with contrast showing the enormous degree of caval compression that can occur in ascities. The aorta is clearly visible (red arrow), but the IVC, which is normally twice the diameter of the aorta, appears as a small white dot, compressed as it is by the large volume of intra-abdominal fluid (blue arrow).

The MRI at right in Figure 20, above, shows a typical ascitic abdomen in cross section. Contrast media has been given intravenously so that the blood vessels show up distinctly. The aorta is clearly visible, but the IVC, which is normally twice the diameter of the aorta, appears as a small white dot, compressed as it is by the large volume of intra-abdominal fluid.

Ascites is not uncommon in cryonics patients, since it occurs in cases of liver failure, cancer which has invaded the liver, congestive heart failure, cirrhosis, ovarian cancer and a number of other conditions. If a cryopatient presents with ascites, one of two things must be done before femoral-femoral CPB is undertaken. The ascites may be drained by the simple expedient of making a stab wound through the body wall and placing a drainage tube in the peritoneal cavity, or an alternative venous drainage site must be selected, such as the internal jugular vein.

Failure to do one or the other of these things will result in either no venous return, or inadequate venous return. In the latter case, the effect will be the very rapid development of massive systemic and cerebral edema due to the increased pressure in the venous circulation.

I would be remiss if I did not disclose that the patient whose case I am about to discuss was a lifelong friend, colleague, and personal and professional mentor to me: Curtis Henderson. My feelings for him may be summed up quite simply by saying that I loved him more than my parents, and more than most other men and women who have touched my life. He was also a man who did much to advance to cryonics; and who suffered mightily as a consequence. He deserved the best cryonics care possible. Having disclosed these caveats, I will endeavor to keep my analysis of this case objective (and as dispassionate as possible). I selected this case for review because it represents the most recent of what has been a series of repeated errors in managing ascites in the setting of cryopatient perfusion that now extends back well over a decade.

Curtis Henderson’s Transport case report (Cryonics Institute Member 165, Patient 95
Date: June 25, 2009) may be accessed at: http://www.suspendedinc.com/cases/Stabilization%20and%20Transport%20Case%20Report%20CI95.pdf

Under the heading “CANNULATION” the following narrative is present:

The vein was 4-5mm in diameter, dark, thin walled, and fragile. Blood flowed freely from it during cannulation. It was ultimately cannulated with a 15 Fr venous cannula inserted approximately 22cm, after attempts to place larger 21 Fr and 19 Fr were unsuccessful.”

Figure 21: The French (Fr) scale of catheter measurement. Even with the advent of ultra-thin-walled flat-wire femoral venous return cannulae, 21 Fr is the minimum size required to achieve adequate venous return in a 70 kg man under low flow conditions. The combined superior and inferior vena cava diameters, through which blood normally returns to the heart, are on the order 40-60 mm. Flow through tubes (cylinders) is not a linear function of tubing diameter, but rather increases or decreases as a function of the fourth power the radius of the tube (for the same liquid under the same conditions of temperature and pressure).

Even without having been present, or seeing any photo documentation, it is possible to state with near certainty that the vein cannulated, as described in the text above, was not the femoral vein. The normal femoral vein in an adult human is never 4-5 mm in diameter, but rather is 2 to 3 times that diameter, and will accommodate venous return catheters in the size range of 22 to 32 Fr (see Figure 21). One of the reasons that gross anatomy instruction has historically been accompanied by the dissection of multiple human cadavers, is that knowledge of both the topographical and internal structural elements of the body is essential to being able to perform medical and surgical procedures competently, such as femoral cut-downs; as well as to diagnose disease. While two students are typically assigned to a single human cadaver, the gross anatomy class as whole will typically be dissecting 12 to 15 cadavers, and this allows for the students to appreciate the considerable individual variation in human anatomy.

Following completion of gross anatomy and a medical education, the physician who wishes to become a surgeon, or to perform specific surgical procedures in the conduct of his practice of medicine, undertakes a residency, or assists with the procedure he wishes to master, until such time as both he and his instructor are satisfied that he has achieved a sufficient degree of competence to operate solo. This is a fairly long process with no shortcuts: there are no textbook autodidacts in the art of surgery. Historically, physician-surgeons have been unwilling to participate in human cryopreservation cases, even with the offer of substantial financial inducements. What this has meant in practice is that vascular cannulation of cryopatients has been carried out by morticians. This state of affairs was reasonably satisfactory until the advent of immediate and continuous post cardiac arrest CPS, which introduced a pressurized circulatory system into the equation and all of the complications attendant thereto, such as obstruction of the surgical field by blood from cut, bleeding tissues, frank hemorrhage, and occasionally, widespread contamination of the operator and the mortuary preparation (embalming) room with blood when a pressurized, large caliber artery was incised, absent proper precautions to control bleeding or deal with the ensuing contamination (i.e. heavy duty face shields, Tyvek or other impermeable clothing, etc.).

Beginning in the late 1970s, two non-physician-surgeon cryonics professionals, Jerry Leaf and myself, made the decision to become proficient at the modest repertoire of surgical procedures then perceived to be needed in the practice of human cryopreservation. We were fortunate in that both of us had had extensive experience in animal research (wherein we had been trained to carry out most of the procedures we sought to master) on dogs, pigs and other mammals. Additionally, both of us had undertaken independent didactic study of both human and veterinary anatomy. Still, we found it necessary to obtain access to human cadavers, and to observe the procedures we were undertaking to learn being performed by skilled surgeons on living human patients. No claim is made here, express or implied, that we ever approached the level of skill of a competent (human) general, cardiothoracic or vascular surgeon.

Our principal deficiencies were lack of speed (competent surgeons operate both with great speed and great precision) and lack of the deep base of experience that facilitates rapid identification and resolution of anomalies, or unexpected problems. These may seem formidable handicaps, and indeed they were.  However, it is uniquely in the nature of cryonics that the most complex and complication ridden parts of the operative procedures we employ present themselves when the patient is in profound, or ultraprofound hypothermia, which means we have the advantage of some ‘breathing room’ when something goes wrong. A femoral cut-down and cannulation for CPB is much less complicated than surgery, instrumentation/monitoring, and cannula placement for CPB using the aortic root and right atrium approach. Another fortunate circumstance is that femoral-femoral CPB in the dog very closely approximates the experience with humans in terms of surgical complications and difficulties, such as cannula placement, bleeding, and even the basic anatomy of the femoral vessels. Thus, extensive survival fem-fem CPB experience with dogs, coupled with (mortuary) practice on human cadavers, provided us with the skill, if not the speed, to perform femoral cannulation for CPB with a high degree of confidence and a low incidence of complications.

The case report continues:

Nearly over the top of the vein, was the artery with multiple feeder vessels between the two. The artery was 6-7mm in diameter, light colored, rubbery and heavy walled. Bright red blood flowed freely from it during cannulation. It was cannulated with a 17 Fr arterial cannula inserted approximately 12cm after attempts with a 19 Fr cannula were unsuccessful.

Figure 22: The anatomy of the femoral vessels as shown in Gray’s Anatomy (A), an idealized artist’s rendering of exposure of the femoral vein for cannulation (B), as seen in a human cryonics patient undergoing CPS in the 1970s (mortician’s cut-down) and as seen in a cadaver prepared for dissection by medical students (D). The femoral artery is quite superficial and the femoral vein is fairly deep. It is easily possible for an inexperienced operator to mistake the saphenous vein (see A & C) for the femoral vein and attempts its cannulation. Only knowledge of the anatomy of the femoral triangle, and prior experience with and observation of the femoral vein, can ensure against this mistake. The experienced operator knows the appearance, location, and above all, the large size of the femoral vein and will, if necessary, increase the depth and scope of dissection until it is identified and raised.

The keys to successful dissection, identification and cannulation of the femoral vessels are a knowledge of the anatomy of the femoral triangle (and its all too common vascular variations) and prior visual and tactile experience with the procedure. As can be seen in Figure 22, above, the femoral vein is a large caliber vessel with comparatively thick walls (for a vein), and it is easily identified, even when collapsed and denuded of color, as is evident in 22-D, above.

Figure 23: If the operator’s thumb is placed on the anterior superior iliac spine and the third finger is positioned atop the pubic tubercle, the index finger will usually be positioned approximately over the femoral neurovascular bundle, which contains the femoral artery and vein (left, above). At right, above, is an anterior view of the right thigh: V=femoral vein; A=femoral artery, N=femoral nerve, 1=adductor longus, 2=adductor brevis, 3=pectineus, 4=iliopsoas and 5=sartorius muscles. If a skin incision is made paralell to the midline as illustrated by the purple line in the figure at left, above, at the midinguinal point, the femoral vein will typically be found a few millimeters, to half a centimeter medial to the femoral artery. The use of these topographical landmarks and knowledge of the underlying muscular anatomy, is essential in performing femoral cut-downs on cryopatients, because the femoral pulse may be absent or not palpable, even when closed chest CPS is ongoing.

To facilitate rapid and accurate location of the correct anatomical area to dissect, a simple procedure may be used to make a first approximation for the skin incision, as shown in Figure 23, above.

The case report continues:

The cannulae were connected to the extracorporeal bypass circuit on the Stockert SCPC minibypass system that had been primed with MHP2 organ preservation solution and cooled by the perfusionist. No venous drainage was observed. No bubbles or air locks were visible in the circuit. The perfusionist applied mild suction and the AutoPulse was re-started to assist with drainage. Still, no venous return could be seen. The venous cannula was slowly backed out while applying suction and automated chest compressions but no return was visible.

Nasopharyngeal temperature was 15C and rectal was 25.6C. A call was made to CI to determine additional site options for cannulation. A jugular cannulation would not interfere with cryoprotection procedures. The patient’s head was repositioned to the contralateral side and the neck swabbed and prepped for external jugular vein cutdown. The AutoPulse was started to aid location of jugular vein.

Pressure to the platysma muscle did not create any obvious jugular pooling. Identification of the external jugular was then made using the mid-point between the angle of the mandible and the top of the clavicle. Using a number 10 scalpel blade, a 3cm incision was made and blunt dissection used to clear the tissue. The jugular was not immediately visible.

Figure 24: The graphic presentation of temperature data for CI Patient 95 documents the lack of venous return as an almost certain consequence of abdominal compartment syndrome, secondary to ascites. The arterial temperature shows a sharp drop as CPB is initiated, however the patient’s (circuit) venous temperature remains constant and does not begin to decline below ambient temperature until CPB is re-initiated an hour after the first attempt was made. The reader is encouraged to study all the data on this graph, and to carefully read the case report in its entirety, because I will be returning to this case and this data in a future installment of this article to make a point about another serious deficiency in the CPS of this patient. More precisely, I will be asking you, the readers, to identify this problem and ascertain its cause.

As the case narrative continues, problems encountered and overcome 20+ years ago in cryonics in-field operations (and overcome long before, in convention surgery) surface and are noted, but are not remarked upon:

“Opening an 8 cm incision and using an aneurism hook for dissection, his field quickly filled with bright red blood. He located the femorals but in separating them, he accidentally cut the artery and multiple feeders between the artery and vein. These vessels were individually ligated and the wound packed while the funeral director enlarged the jugular incision that had been opened earlier and isolated the jugular. A 17Fr venous cannula was inserted into the jugular vein approximately 30cm and connected to the venous perfusion line. Mild suction was applied.

Venous drainage was observed.”

Morticians are unprepared to perform vascular surgery on cryonics patients who are undergoing CPS, or who have been subjected to CPS with heparinization and prompt external cooling (usually with bulk ice present and compressing the tissues). The rough handling of the tissues and vessels that they are accustomed to using with impunity on corpses, quickly degenerates into catastrophes for which they have no ready solution. Additionally, the absence of high capacity electrically powered suction (‘hot’ suction) leaves the operator unable to visualize the surgical field. Attempts to blot the wound with absorbent material merely result in replacing one visualization obstruction with another; since the instant the sponge is removed from the wound, it refills with opaque blood. These are foolish and inexcusable errors only because they have been made before, are documented in the cryonics case literature,[136] and have solutions that are easily learned and implemented – but only if those attempting to practice cryonics as medicine take the time, and exercise the diligence required to learn them.

The  problem of ascites in the context of femoral-femoral CPB has occurred at least five times in cryonics cases that I know of, and in three of those five cases, it happened to personnel who had experienced the same problem before. And yet, the problem was not addressed and the same rote procedure was followed, despite the fact that problems were evident. I will say that in two cases where there was no venous return they did eventually stop perfusion because they realized that ‘something was wrong.’ In this case, the presence of a skilled perfusionist undoubtedly prevented the iatrogenic disaster of more than a very brief period of injection of arterial perfusate in absence of sufficient (or any) venous return. There are myriad other problems and deficiencies in this case (as adjudged from the report), all of which were and are avoidable with the hard-won, existing base of knowledge, wisdom and professionalism that has been generated since the scientific practice of cryonics was begun by Fred and Linda Chamberlain, Greg Fahy and me over 30 years ago.

Nevertheless, the real solutions to the problems discussed here are not easy, because they demand the acquisition of professionalism, knowledge, and skill in the context of cryonics as medicine. I personally believe that Jerry Leaf and I came very close to doing that in the decade between 1981 and 1991. But we failed. Why we failed will be discussed at a later time. Suffice it to say that the problem of maintaining professionalism is a nettlesome one in medicine, engineering and other demanding disciples that are vastly more developed than cryonics is today, and there will be no quick fixes. In cryonics, where almost all the feedback we get from our patients must be artificially generated, the problem will be much more difficult to solve. However, no progress will be made absent understanding and acknowledgement of the need to acquire and interpret the patient’s medical records in a timely fashion, whilst being informed by both medical and cryonics knowledge and professionalism.

End of Part 4

References

119.     Hippocrates: Of The Epidemics: http://classics.mit.edu/Hippocrates/epidemics.1.i.html; 400 BCE.

120.     Huikuri H, Mäkikallio, TH, Peng, CK, Goldberger, AL, Hintze, U, Møller, M.: Fractal correlation properties of R-R interval dynamics and mortality in patients with depressed left ventricular function after an acute myocardial infarction. Circulation 2000, 4(101(1)):47-53.

121.     Laitio T, Huikuri, HV, Kentala, ES, Mäkikallio, TH, Jalonen, JR, Helenius, H, Sariola-Heinonen, K, Yli-Mäyry, S, Scheinin, H.: Correlation properties and complexity of perioperative RR-interval dynamics in coronary artery bypass surgery patients. . Anesthesiology 2000, 93(1):69-80.

122.     Pikkujämsä S, Mäkikallio, TH, Sourander, LB, Räihä, IJ, Puukka, P, Skyttä, J, Peng, CK, Goldberger AL, Huikuri, HV.: Cardiac interbeat interval dynamics from childhood to senescence : comparison of conventional and new measures based on fractals and chaos theory. Circulation 1999, 27(100(4)):393-399.

123.     Schmitt D, Ivanov, PCh.: Fractal scale-invariant and nonlinear properties of cardiac dynamics remain stable with advanced age: a new mechanistic picture of cardiac control in healthy elderly. Am J Physiol Regul Integr Comp Physiol 2007, 293(5):R1923-1937.

124.     Verweij BH, Muizelaar JP, Vinas FC: Hyperacute measurement of intracranial pressure, cerebral perfusion pressure, jugular venous oxygen saturation, and laser Doppler flowmetry, before and during removal of traumatic acute subdural hematoma. J Neurosurg 2001, 95(4):569-572.

125.     Marx JA e (ed.): Head injury (Chapter 38). Philadelphia: Mosby Elsevier; 2009.

126.     Guresir E, Schuss P, Vatter H, Raabe A, Seifert V, Beck J: Decompressive craniectomy in subarachnoid hemorrhage. Neurosurg Focus 2009, 26(6):E4.

127.     Daboussi A, Minville V, Leclerc-Foucras S, Geeraerts T, Esquerre JP, Payoux P, Fourcade O: Cerebral hemodynamic changes in severe head injury patients undergoing decompressive craniectomy. J Neurosurg Anesthesiol 2009, 21(4):339-345.

128.     Eberle BM, Schnuriger B, Inaba K, Gruen JP, Demetriades D, Belzberg H: Decompressive craniectomy: surgical control of traumatic intracranial hypertension may improve outcome. Injury, 41(7):934-938.

129.     Klebanoff G: Early Clinical experience with a disposable unit for intraoperative salvage and reinfusion of blood loss intraoperative autotransfusion). Am J Surg 1970, 120:718-722.

130.     Symbas PN: Extraoperative autotransfusion from hemothorax. Surgery 1978, 1078 (84):722.

131.     Phillips SJ, Ballentine B, Slonine D, Hall J, Vandehaar J, Kongtahworn C, Zeff RH, Skinner JR, Reckmo K, Gray D: Percutaneous initiation of cardiopulmonary bypass. Ann Thorac Surg 1983, 36(2):223-225.

132.     von Segesser LK, Kalejs M, Ferrari E, Bommeli S, Maunz O, Horisberger J, Tozzi P: Superior flow for bridge to life with self-expanding venous cannulas. Eur J Cardiothorac Surg 2009, 36(4):665-669.

133.     Kirkeby-Garstad I, Tromsdal A, Sellevold OF, Bjorngaard M, Bjella LK, Berg EM, Karevold A, Haaverstad R, Wahba A, Tjomsland O et al: Guiding surgical cannulation of the inferior vena cava with transesophageal echocardiography. Anesth Analg 2003, 96(5):1288-1293, table of contents.

134.     Colangelo N, Torracca L, Lapenna E, Moriggia S, Crescenzi G, Alfieri O: Vacuum-assisted venous drainage in extrathoracic cardiopulmonary bypass management during minimally invasive cardiac surgery. Perfusion 2006, 21(6):361-365.

135.     Abdel-Sayed S, Favre J, Horisberger J, Taub S, Hayoz D, von Segesser LK: New bench test for venous cannula performance assessment. Perfusion 2007, 22(6):411-416.

136.    Darwin, M:Neuropreservation of Alcor Patient A-1068. Cryonics 1985, 6(4):10-19:  http://www.alcor.org/Library/html/casereport8504.html

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1968 AD > Cryonics > Reboot http://chronopause.com/index.php/2011/03/17/1968-ad-cryonics-reboot/ http://chronopause.com/index.php/2011/03/17/1968-ad-cryonics-reboot/#comments Thu, 17 Mar 2011 08:41:14 +0000 admin http://chronopause.com/?p=541 Continue reading ]]> Work out your own salvation with fear and trembling.”

-      Philippians 2:12-13

Left: Mike Darwin at the Cryonics Society of New York in1971 (Inset: in Russia July, 2008).

Future Shock Now

By the time you are 50, if not before, you will inevitably encounter a shocking realization: some of the people who are your colleagues, friends and even family, will have no idea what you are talking about when you mention an event or an object that is as fundamental to your experience as a shopping excursion, making a telephone call, eating ice cream, or using a pencil. For the first time it becomes clear to you that many of the most important and formative experiences in your life are rapidly passing out of living memory for most of those with whom you now inhabit the world. When this happens, it is at once shocking and painful, because it forces the twin realizations upon you that you are no longer young, and that you have begun to outlive your time.

If you are a cryonicist this experience unavoidably raises the spectre of how much more shocking, painful and disorienting the really extreme temporal displacement of being revived from decades, or even centuries in cryopreservation will be.

Age Distribution of the Population in the United States as of 2000

Roughly half of the people alive in the US today are 30 or younger, were born in 1978 or later, and are thus 25 years younger than me. They have no experience of a world without tiny, hand-held electronic calculators (most do not know what a slide-rule is), mobile phones, or readily available and affordable photocopying. The impact of these technological developments has been at once profound and subtle. As one small example; I began my intellectual life searching for scientific papers using walls of bound volumes known as the Index Medicus.

A small part of the Index Medicus, now in the museum of the Weill Cornell Medical Library.

I obtained information from papers that I read in the library not by photocopying them, or parts of them, but by making copious notes on 3”x5” cards and in a bound composition book. Onionskin tracing paper was used to copy graphs or charts deemed critical. Being forced to obtain information from publications in this way fostered careful reading and subsequent abstraction of important ideas in a concise and efficient way; it was a much poorer world then, and even 3”x5” cards were a significant expense.

Typical Mid-20th Century Slide Rule: The slide rule was a simple analog computer; essentially a mechanical look-up table. It was a useful tool for finding roots and logarithms and allowed for multiplication and division, but, unfortunately for me, did not permit addition or subtraction.

Typing dozens of pages of right justified text using a mechanical typewriter (and carbon paper to make copies) is probably unimaginable to this cohort of the population, yet these are experiences that were not only routine, it was not even imagined that they would ever end. Futurists in 1968 envisioned human interplanetary space travel and intelligent computers for the year 2001; not personal computers, the Internet, or tiny electronic devices that easily fit in your pocket, let you talk to anyone almost anywhere in the world for a pittance, watch television (all 200+ channels; there were 4 channels when I left home at the age of 18), and read your (electronic) mail, pay bills… It was inconceivable that the same device would also allow you to get restaurant recommendations, place your dinner order and then guide you, turn by turn, (on foot or driving) to your destination in a calm, mechanical voice.[1] It was even more inconceivable that these feats would be achieved in part, using a plethora of satellites in geosynchronous orbit that also tell you where you are, anywhere on the planet’s surface, with accuracy to within a meter or so.

While these changes have had profound cultural impact, arguably they do not have as much human impact. Imagine a world where the birth control pill has not been invented, a twice divorced and remarried woman could justifiably be expected to suffer social ostracism, and a woman being beaten by her husband, within limits, was a distasteful, but in practice, not actionable event. That was the world I was born into and it is a world I remember well. To those Americans under 30, the words Khrushchev, Vietnam, hippie, Saturn-5 and Nixon, will forever be abstractions, if they mean anything at all. If reanimation for those cryopreserved now becomes possible, they will be facing a shift in technology and values that is hard to comprehend.

Adjusting To Revival from Cryopreservation

In pondering this problem many years ago, I conceived of the idea of having patients virtually live through the interval between the time they were cryopreserved and the time they were revived in order to catch up, or adjust. This would be an accelerated process where a week, a day or even an hour of real time would equate to a year of subjective time “lost” in storage. Clearly, this would take place as a simulation, and beyond the purpose of defusing shock, it could also serve to educate and rehabilitate. The patient would wake up one day in his life at a point before his cardiac arrest deemed appropriate, get out of bed, and continue, as usual, with the normal routine of his life. The trajectory of his experience would alter gradually, probably in ways not now imaginable; in order to ultimately equip him with the insights, knowledge and skills needed to survive in a world transformed by time and technology.

Most of you reading this will have had the thought, be it a fantasy or a nightmare, that you might be living in a simulation, or that otherwise the reality you are experiencing is being manipulated in some way. I should imagine that if you are sane, this idea is just a remote gedanken experiment – the kind of thing that is very far removed from logical, let alone emotional reality.

Time Warp

One night a few weeks ago, while I was visiting Russia, I was walking along the street in Moscow with a small group of Russian cryonicists and we were passionately discussing the mechanics of cryonics. My visit to Russia had been intense; non-stop work and conversation from 0900 to 2200 or 2300 most days. We had walked past a large black statue of Comrade Lenin, with his arm outstretched, and now we were passing a McDonald’s. Ahead, the red and white logo of a KFC, with

“the Colonel” on it, lit up the sidewalk. I had been on a very similar street 40 years before, in Soviet times, also at night, but with a Soviet Intourist[2] minder and no glaring capitalist kitsch.

A McDonald’s Restaurant in Moscow

Now, consider these facts: I am 53 years old. I am in Moscow with two Russians who were not even born when l was last in Russia. Cryonics is in a ghastly state and is something from which I am effectively exiled. And, again, try to understand: I am walking by a McDonald’s restaurant in Moscow, Russia. The young men I was with could not understand the cognitive dissonance that the words “McDonald’s restaurant in Moscow, Russia” evoked in me. They were all in their 20s, or early 30s.

But, more interesting still, as I walked along the street it dawned on me that I am in cryonics again. Only, it is not 2008, it is 1968. No, it is not the 1968 that happened six years after the Cuban Missile Crisis in the US. It is an alternate1968.

Russia is, in many ways, much like the US was circa 1962-1968. While it is not the US then, nor is it any place but what it is: Russia in 2008 CE, there is nevertheless, the powerful sense that I am back in time; literally back in time. In part, this feeling is due to my growing awareness of countless little things that had vanished from my everyday experience without my noticing them having gone. I see old people limping along the streets with canes, and I gradually realize that this once utterly commonplace sight is largely gone in “my” world because now, if you are old and suffer from degenerative joint disease, you either have a hip replacement, a knee replacement, ride around on an electric scooter, or you are bedbound or dead.

I smell body odor in the air while waiting in line at the market near where I am staying, and sometimes I smell it on the Metro. Not bad, not offensive, just something that was commonplace in my childhood and that has also vanished in an era of advertiser-mandated ‘deodorant’ use. I realize, too, that here in Russia some people still have distinctive odors; the odor of pipe tobacco and menthol, camphor and horehound, or the smell of smoke from standing around open fires. Some old women smell of lilacs or something sweet like vanilla, as they once did in my daily experience ‘long’ ago.

To me, this Russia is a pastiche of the years in the US between 1955 and 1968: people are dressed more plainly than in the West today, and it is clear that clothing and shoes are still at a premium here. I remember from my boyhood how expensive shoes were, and how it was a minor ritual to buy a new pair.

Things are dirtier there, much, much dirtier than they are now in the US and Europe. I then remembered how much infrastructure was covered in grime the US in my youth, and I’ve noticed that white people (not brown people, but white people) pick up the trash and wash the floors in public spaces with a bucket and a brush just as in the US in my childhood years.

And I’ve noticed that there are no black people, absolutely no black people to be seen. In fact, in my 2 weeks in Moscow and Russia, I did not see a single person of color, with the exception of the occasional Mongol, or affluent Chinese tourists. This, in 2 weeks of extensive, daily travel in Russia – travel on the Metro, on the rail system – in the city and in the suburbs – not a single observed black person and barely a hint of people with skin darker than a light skinned Hispanic, or a well tanned Midwestern farmer in summer.

Paint was a very expensive thing when I was growing up and money was tight. Things didn’t get painted as much in that era and that is how it is in Russia today, especially in the countryside. I sometimes see drunken men in shabby clothes at a train station or on a residential block; and it comes back to me how common this was in the US in my youth. There is also the relative absence of regulation. There are no zoning and planning commissions, no suffocating mire of regulatory restrictions on the purchase of chemicals, or experimentation with animals. The Russian attitude towards vivisection and invasive experiments on dogs, cats or other mammals is even more indifferent than was the case in the US 40 years ago. In any choice between the welfare of people and the welfare of other animals, people come first. There is no mortuary or cemetery regulation in Russia, no OSHA, no Pharmacy Board and no Bureau of Medical Quality Assurance. In an eye blink one the most regulated countries in the world became one of the least regulated. And while this is rapidly changing as abuse begets government intervention, the situation today is mostly one where graft determines the outcome of almost any regulatory issue.

I realize how vastly wealthier in chattels we in the West have become since that 13-year interval in the middle of the last century. People owned far, far fewer things during that period in history (and before) in the US. Clear mental pictures of my Aunts’ and Uncles’ apartments in New York City, and of their friends’ apartments there have been flooding my mind. They were sparse spaces even when crowded with many peoples’ things. It wasn’t just that people owned fewer things; there were fewer things to own. Yes, computers are everywhere in Moscow, and mobile phones, but in that world between 1955 and 1968 there were no food processors, no televisions in kitchens and bedrooms, no curling irons, fondue pots, or walls covered with well proportioned and nicely matted and framed art. Walls had bad art; small pictures that interrupted the expanse of blank plaster, like a postage stamp on an unaddressed envelope; out of proportion and out of place. All of these things I had forgotten, and yet, here I was and it was all just as it once was in my experience 40 years ago.

And then there is cryonics. It is only 15 years since the Soviet Union collapsed. Before that time (and even now) Russia was cut off from the rest of world in many ways. It is still very, very difficult to get information in Russia on scientific matters unless you can read English; and even then it can be problematic. In short, the whole history of cryonics, all the media coverage, all the seepage of the idea into the cultural water supply that has happened over the past forty years effectively never happened in Russia! Robert F. Nelson never picked up a tabloid newspaper and decided to become involved in cryonics. Chatsworth has not happened. None of the past 40-years of my life experience exists in this place where I am.

The cryonicists I am with, and with whom I am talking, are behaving in the same way and talking about the same things, and doing so in exactly the same manner as happened over 40 years ago in the US. I realize it has been decades since I have had such conversations about cryonics with anyone. Most of the topics we are so earnestly discussing are now consigned to the past, because they are long ago decided issues. What expedient legal mechanisms should be used to gain and maintain custody of patients? Should cryopreservation funding be configured as an insurance program administered and profited from by the cryonics organization itself, or should conventional insurers be used? Should there even be members, or should there be clients or customers instead? What kind of place is suitable to store cryopatients; a cemetery, a dedicated building, a leased industrial building? These are all issues long ago debated and put to rest in cryonics – in the West, at least.

Where the Present is My Past

Here, my present is my past, because exactly the same problems have begun to occur in exactly the same way with exactly the same results. In every detail it is the same, exactly the same. The relatives of most of the patients were unhappy at the condition of the KrioRus facility and have moved their loved ones to private care that each is managing personally. I can hear, actually hear Pauline Mandel and Nick BeBlasio carping about the Cryo-Span facility on Long Island, and complaining that patients shouldn’t be stored that way – only they are speaking Russian! I cannot understand a single word they are saying, yet I understand every word of it, with perfect clarity.

Fred Horn, Curtis Henderson and Saul Kent circa1969-1972

I meet people who speak little or no English, but they are people I knew well: Curtis Henderson (at 40), Saul Kent (in his late 20s), Paul Segall (in his early 20s) and Fred Horn (in his late 40s). They are all there; not a single person is missing from that time in my life. Yes, they speak Russian not English, and no, they do not look the same; and yet they feel exactly the same; the facial expressions, the ‘unique’ combination of personality traits each person had, their world view, their approach to problem solving (or lack of approach), it is all the same – functionally identical. I meet John Bull as he was 40 years ago, and Marce Johnson and Lucille Doty and Herman Earl and Bob Krueger as they were then in the early days of cryonics. They occupy the same stations in life, live the same lifestyles, and appear to think the same thoughts. I try, but I cannot find a single person from the early days of cryonics who is not there; including the now nameless and mostly forgotten hangers-on, lunatics, fools, and – not be omitted from my inventory – the occasional man or woman who only now, with many years of life experience, I recognize as distilled, sociopathic evil.

It is 1968 in cryonics here. Bedford and the first wave of patients that followed him have just been frozen; they have different names, genders and stories, but it is as it was then. The same events are playing out; the same frustrations and the same mistakes are happening again, along with the same faltering steps at progress. I have reached the point where I know what certain people will say before I ever meet them, and I realize that I more often than not I know the course of events exactly as they unfolded, even though I have not yet been given the narrative. The story is the same, and that is terrifying. But, strangely, it is something else as well, because, you see, it is still 1968 in cryonics in Russia – and I can see the future. I can see it with a clarity that no one has been granted since Cassandra – and Cassandra was a myth.

A Different Culture and a Different World

I fear I know what is to come, more or less. Yes, yes, it is mostly playing out as it did then; the idea of cryonics has entered the culture and important people in intellectual and academic life have taken note and become interested. It is also true that there is the supernova of media; just as there was when cryonics first began; the endless cycle of chat shows (very much in the style of the late 1960s in the US), the newspaper and magazine articles…

Left: Danila Medvedev, President of KrioRus

Cryonics is new, completely new all over again, but with differences, big differences, possibly critical differences. The guests and audiences on the chat shows do yet not mock KrioRus President Danila Medvedev, or the others who advocate cryonics; they listen with some interest. Isaac Asimov exists here, but his name is Yuri Nikitin, and he is signed up for cryonics and a vocal advocate for cryonics, not a relentless public adversary. He is a man undertaking life extension interventions on his 90+ year-old mother and himself. He is one of Russia’s most popular science fiction and fantasy authors.

But it is also important to remember that Russia is not, and never was the US, or Europe for that matter. Ninety-one years previously an alternate history played out there; its people were stripped of the fog of religion, and their culture was remodelled in ways never experienced in the West. But, deeper than that, much deeper, is something that I’ve known for a long time, but that has been submerged beneath the turbulent surface of my consciousness: Russia was never the West.

Konstantin Tsilkovsky Vladimir Mayakovsky Nikolai F. Fyodorov

Russia produced Fyodorov, Tsilkovsky and Mayakovsky — men who were immortalists and Transhumanists at the start of the 20th Century, not at its close. And it was Russia that produced Bryukhonenko, Demikhov, and Negovskii: the men who invented extracorporeal circulation, transplantation and resuscitation medicine, and who first demonstrated that consciousness and identity reside in the brain. It was in Russia, not in the US or Europe, that one of the country’s leading heart surgeons,  Nikolai Amosov, wrote Note’s From the Future; a novel about cryonics, a novel in the tradition of Mayakovsky – a tradition that had been forged 60 years previously.

Nikolai Amosoff, 1913-2002

Russia is a country where 40% of the population are atheists and less than 15% identify themselves as Orthodox Christian. Russia is an Anglo version of Japan and China; all whites, no minorities, and they are keeping it that way by intention, and doing so with stunning effectiveness. Russia is also a country where 14% of the adult population states, with no qualifications, that they want to live forever, and where 40% state that they “want to live as long as possible in good health.”

No, it is not the US in 1968 and it is not cryonics in the US in 1968 and, perhaps most significantly, the worst mistakes made in the history of cryonics in the US have not been made in Russia, not yet. Perhaps they need not be made at all?

A Moment of Clarity or a Moment of Madness

So, there I was, walking by a McDonald’s in the country that, when I was 7-years-old, seared into me forever black and white memories of Kennedy, President Kennedy, standing before huge enlargements of photographs and pointing out oblong shapes in the Cuban soil that looked like insect egg casings – at once fascinating and disturbing. I sat in front of the television with my parents watching as the President  pointed out those strange shapes while telling me, in tense and measured words, that the world was on the brink of war, indeed on the brink of nuclear annihilation. What does a 7-year old-boy understand of global thermonuclear war? What can he understand? Nothing, really, nothing more or less than the inescapable reality that his parents are afraid, deeply, viscerally afraid, and that that is something completely new to his experience; something he has never seen before, and never wants to see again.

Vladimir Demihkov (1950); inset conscious juvenile dog (head and upper body) engrafted on adult (supporting dog), circa 1942.

I am in Moscow, in the hub, the core, the gravitational black hole of what once was Soviet Communism and the heart of an empire that could make the West tremble and spend, and tremble and spend. I am in Moscow, in Russia, and I am thinking all these things that I have written about here, and more besides, and it comes to me that this cannot, this absolutely cannot be real and that someone is toying with me. Somehow, somewhere, sometime ago, my heart stopped, I was formally pronounced dead and then, all the right things were done. I was lucky. I had been incredibly lucky.

But when had it happened? Had I sickened with AIDS in late 1980s, like most of the other gay men that I knew? Had Jerry Leaf sawed through my sternum and cut off my head? And if so, who had placed the Thumper on me? Who had given me the meds and poured the ice around me in the PIB?

Mike Darwin at the Museum of the  History of Cardiovascular Surgery, Scientific Center of Cardiovascular Surgery of the Russian  Academy of Medical  Science with S.S. Bryukhonenko’s “autojector,” the first successful extracorporeal support device, 2008. Inset:  Bryukhonenko with the autojector, 1933.

Or had it been a heart attack? Was it me and not Jerry who suffered a sudden cardiac arrest late that July night in 1991? I certainly had the family history for it; it would not be surprising. Was it cancer, or some twisted, unusual thing, like an abscessed tooth that flashes over into sepsis, unconsciousness and death – or in my case – an interruption in life, a reboot?

If that was so, then surely it must have been then that it had happened, at that time in my life when things were going well, when I was happy and productive. That would make sense! It must have happened before the nightmare began, before Dora Kent. Yes, that had to be it! Everything from sometime before that December, that terrible December in 1987, was not real. It was a punishment, a penance, or maybe some kind of test, or necessary learning experience to teach me things I had not learned before, and that I must know before I was turned loose in the world again?

There was simply no other explanation for the utterly alien nature of this “future” I now inhabited. That was the only answer that made sense, and it was the answer that, for a few moments in time, I instinctively knew was the right one, and believed.

I turned to my companions and tried to explain what had just happened inside my head. I tried to explain while still under the ether of the experience; still groggy with the fading emotional certainty that I had been ‘suspended,’ for the word cryopreserved was still in the future, yet to be applied to cryonics by Brian Wowk. I tried to explain, and I failed utterly, probably as I have failed again here, and will always fail in attempting to communicate what I experienced that night in Moscow.

Second Sight

As the Aeroflot Airbus A319 gained altitude leaving Moscow behind, I looked out the cabin window, wistful and wondering. How will cryonics turn out this time, in this place? Cryonics is just beginning to take root in the land receding below me, and in almost every respect it is still 1968 for cryonics in Russia. As I turn toward the steward making his way down the aisle, I catch the ghostly, reflected glimpse of myself in the cabin window. Moscow is behind me now, and while it may be 1968 for cryonics there, it is not 1968 for me, and it has not been so for 40 years. I am old and growing rapidly older. All the second sight that 40 years of life spent in the service of cryonics has given me cannot restore the youth required to start life anew. I turn and contemplate that visage in the window, more clearly visible now as the sun edges closer to the horizon, and the Perspex becomes reflective.

Second sight, the dictionary tells me, is a noun defined as “the power of discerning what is not visible to the physical eye, or of foreseeing future events, especially such as are of a disastrous kind; the capacity of a seer; prophetic vision.” This gift allows me to look, effortlessly, past the skin and bone of my face, deep into my brain, and deeper still to peruse the layers of tangled cells woven into a fabric that is briefly, rhythmically distorted by each pulse of blood racing through it. The fabric has begun to look thin and is frankly threadbare in spots. It is a shadow of the dense and pulsing tangle it once was in my youth. It is pared down – well compensated considering the number of neurons lost, and the even greater diminution of the connections between them. It is a folded and refolded blanket of cells racing towards dotage, and already two-thirds of the way to its destination. There is horror in this vision and in the realization it invokes in me, and I am, once again, walking along that street in Moscow with a group of young Russian cryonicists.

As Aschwin deWolf so elegantly wrote[3], “We often wonder why not more people choose cryonics to improve the odds of being part of the future. Could it be that important reasons for not doing so involve scenarios of the future that are too unpleasant to discuss in decent company?” He goes on to quote, appropriately enough, Fydor Dostoevsky:

“Every man has some reminiscences which he would not tell to everyone, but only to his friends. He has others which he would not reveal even to his friends, but only to himself, and that in secret. But finally there are still others which a man is even afraid to tell himself, and every decent man has a considerable number of such things stored away.”

Maybe that blinding flash of insight was the reality after all. I reflect on Dostoevsky’s remarks and search my soul. There is, I suppose, always a silver lining. If this is a life of penance, perhaps to be followed by some meting out of justice, then I have many years ahead of me before I descend either into dotage or redemption. I smile inwardly as I think that sins such as mine might even take an eternity to atone for.

But no, this not the case: the world is as it seems, and I am headed home.

Milton’s words that repose framed in wood and glass next to the front door of my home in Northern Arizona (sometimes baking in the desert heat and sometimes freezing in its cold) march slowly through my mind:


“Is this the region, this the soil, the clime,”
Said then the lost Archangel, “this the seat
That we must change for Heaven?–this mournful gloom
For that celestial light? Be it so, since he
Who now is sovereign can dispose and bid
What shall be right: farthest from him is best
Whom reason hath equalled, force hath made supreme
Above his equals. Farewell, happy fields,
Where joy for ever dwells! Hail, horrors! hail,
Infernal world! and thou, profoundest Hell,
Receive thy new possessor–one who brings
A mind not to be changed by place or time.
The mind is its own place, and in itself
Can make a Heaven of Hell, a Hell of Heaven.
What matter where, if I be still the same,
And what I should be, all but less than he
Whom thunder hath made greater? Here at least
We shall be free; th’ Almighty hath not built
Here for his envy, will not drive us hence:
Here we may reign secure; and, in my choice,
To reign is worth ambition, though in Hell:
Better to reign in Hell than serve in Heaven.
But wherefore let we then our faithful friends,
Th’ associates and co-partners of our loss,
Lie thus astonished on th’ oblivious pool,
And call them not to share with us their part
In this unhappy mansion, or once more
With rallied arms to try what may be yet
Regained in Heaven, or what more lost in Hell?”

God, I reflect, was kinder to Lucifer than to us. Consigned to Hell, He was at least allowed to live. And he was not subjected to the horror of disease, old age and death.

The aircraft is now over the vast expanse of the North Sea. Hell, I reflect, is only an ocean away, and I will be there soon enough. Yes, God was infinitely kinder to Lucifer, for even in his Lake of Fire, the Fallen Angel could reflect with some satisfaction that, “To reign is worth ambition, though in Hell; Better to reign in Hell than serve in Heaven.” God and the Devil, Heaven and Hell; in Russia these ideas are only for the ignorant, the foolish, the feeble minded, and the crafty users of men who prey on thir inborn fear of senseless suffering, death and oblivion.

We are solidly in the stratosphere now and headed West towards the setting sun. I think of myself standing in the dusty streets of Luxor in southern Egypt. I look out across the Nile in my mind’s eye. The Ancient Egyptians had divided the city into two parts along the banks of the Nile. The East, the province of the rising sun and day, was the land of the living, while the Western shore of the Nile was the land of the dead. I am headed due west now, but where am I headed, towards life, or death? The steward has just brought me tea and has asked if there is anything else I want? “Yes,” I reply, “immortality and happiness.” “You are a Christian?” he asks, warily. “No, no, I respond,” smiling, “just a tired old man afraid of the coming dark.” He withdraws with a guarded look, no doubt thinking to himself, “Another crazy American.”

The image above was originally created to appear in Life Magazine in January, 1967 to accompany a feature article documenting the cryopreservation of the first man, Dr. James H. Bedford. However, due to the tragic deaths of the three Apollo astronauts Chaffe, Grissom and White, the presses were stopped after less than a million copies had been printed. A second first week of February issue of Life was printed and substituted. Copies of the original 3 February issue that had been printed were distributed to subscribers who lived mostly in Southern or rural areas of the US.  As a consequence, the image above did not achieve widespread media distribution until 1968. It continues to be a staple image used by media around the world to illustrate stories about cryonics even though the technology pictured has not been used since 1968. The photograph was taken by the renowned Life photographer Henry Groskinsky.

Notes from the Future

I pick up one of the Russian language magazines the steward has left as reading material for the remainder of the flight. As I leaf through its pages of incomprehensible Cyrillic, my eye is caught by what is, to me, an iconic image. It is a photograph that saturated print stories about cryonics in 1968. The article that accompanies it begins: “Крионика – это практика замораживания обречённых на смерть пациентов до ультранизких (криогенных) температур и их дальнейшего сохранения в жидком азоте.”

When the steward returns for my empty cup I ask him what that sentence means. He looks intently at the page and clearly reads on beyond that first line.

“It’s about preserving dying people in the extreme cold until they can cure them,” he says.

“Does it say dying people or dead people,” I ask him?” “Dying people,” he responds, “why would anyone want to do that to dead people? If your heart stops you are not always dead, no?” he responds. I thank him and look out the window. For onto 40 years now, I have been going back and forth and walking up and down over that earth, now spread out below me, in order to make exactly that point. Possibly, just possibly, there is some hope after all.

- Mike Darwin, August, 2008, London, England


[1] I was at least was prepared for the idea of such a device by reading SF author Fred Pohl’s prescient book The Age of the Pussyfoot (1965) about a cryopatient , Charles Forrester, who  is revived from cryopreservation in the year 2527, having been killed in a fire 500 years earlier.  Pohl envisioned that everyone would have a ‘Joymaker’ a person communications device that had all of these functions: Access to basic computing power for money management and similar activities; Access to libraries at any time, in any place; Education of children, each of whom had a special Joymaker; Health and medical care- the Joymaker continuously monitored vital signs, physiological and psychological status. and the central computer could order it to dispense medication, or it could solicit emergency medical assistance; Message store and forward functions, which we now call voice mail; Ordering food and drink, whether at home or in public; All payment was done using the central computer; Ordering other goods for delivery; Public Address system – any group of people could hear a public announcement on their Joymakers; Locating people; the central computer could track the position of any Joymaker, and by extension, its owner. This information could be made available (at the owner’s discretion); Jobs not requiring physical presence such as product evaluation and psychological reactions of the ‘employee’ to advertising, entertainment or news. (http://en.wikipedia.org/wiki/The_Age_of_the_Pussyfoot)

[2] Intourist was the official state travel agency of the Soviet Union, in fact it was the only travel agency and the only way to visit the Soviet union as a tourist.  It was founded in 1929 by Joseph Stalin and was staffed by NKVD (which became the KGB) officials. Intourist was responsible for managing the great majority of foreigners’ access to, and travel within, the Soviet Union. Intourist was, at one time, the largest tourism organization in the world incorporating or co-opting banks, hotels, and bureaux de changes. Vistors to the Soviet Union were assigned an Intourist minder who stayed with them throughout their visit and supervised all interactions of the tourist with the local population.

[3] http://www.depressedmetabolism.com/sophistry-and-illusion-can-economic-man-resurrect-ethics/

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Maxim, Pumps, and Flow Measurement http://chronopause.com/index.php/2011/02/27/maxim-pumps-and-flow-measurement/ http://chronopause.com/index.php/2011/02/27/maxim-pumps-and-flow-measurement/#comments Mon, 28 Feb 2011 02:49:16 +0000 admin http://chronopause.com/?p=353 Continue reading ]]> By Mike Darwin

This post is in response to a comment made by  Abelard Lindsey  on 02-27-2011. Since my response necessitates the use of illustrations, I am making it here, rather than in the comments section.

Abelard Lindsey
kurt2100kimo@yahoo.com.tw
71.236.250.197

If Melody Maxim thinks the existing organizations are so screwed up, she is free to get up off her ass and start a new organization that will do things the way she thinks they should. It’s easyto sit on the sidelines and to criticize the efforts of others. It is more difficult and takes more character and work ethic to get up off of one’s ass and to actually do some effort to make things better.

The ball is in Melody Maxim’s court. Its time for her to put up or shut up.

______________________________________________________________

You know, the ironic thing is, when Maxim first arrived on the scene, I was really pleased, and I looked forward to being able to work with her in some capacity. I had dealt with a number of perfusionists before, and in fact employed two perfusionists when I operated BioPreservation, a cryonics service provider company in the 1990s. My communication with Maxim was necessarily constrained when she was first hired by Suspended Animation, Inc., because I’d learned from previous experience that it is essential to let people gain their own unbiased experience of an enterprise, and especially of a new employment situation, before any negative input is given. Not only is criticizing someone’s employer under such circumstances considered sleazy behavior, it also just doesn’t work. You are perceived as having an axe to grind, being jealous, and so on.

Additionally, my first introduction to her had come in the form of an unexpected phone call from Charles Platt, who put Maxim on the phone to “meet” me. It was a brief (and from my end) awkward conversation. It would have been out of place for me to have then contacted her to criticize SA. I figured she’d come to her own sorry conclusions in due time, and if she was competent, it would be in a short period of time. Subsequently, Charles provided her with a copy of an extensive critique of SA that I had done as a favor (unpaid) to Bill Falloon. I was also asked for specific technical commentary on the in-field extracorporeal circuit for blood washout that SA was trying to develop. There, I apparently made the mistake of disagreeing with Maxim on just one point: the desirability of roller pumps (tubing pumps) over centrifugal pumps for use in such systems. This apparently angered her, and it was all downhill from there. Subsequent interactions with her (at a distance) when she was consulting for CI apparently enraged her.

Her response to my comments about centrifugal pumps in the setting of both asanguineous blood washout/recirculation and cryoprotective perfusion should have been a red flag at the time. At first glance, centrifugal pumps soundly beat roller pumps and other “positive displacement” pumps for extracorporeal support. They are lighter, provide more flow for less power (and weight), do less damage to blood cells, and, most importantly, they cannot pump “bulk” or macro-air into the patient’s circulatory system. If you empty the venous reservoir feeding a centrifugal pump, it loses prime and stops pumping. The impeller continues to spin, but there is no longer any flow. They are thus “inherently safe” in terms of pumping macro-air.

Figure 1: Centrifugal pump at left, and positive displacement roller pump, at right. Centrifugal pumps require a flow measurement device, and in medical applications this is typically an electromagnetic or ultrasonic flow meter, the transducer for which snaps around the tubing, or a special cuvette, as seen at left, above.

So, what’s not to like? When scientific-cryonics got started in the early 1970s, the standard pumps being used in extracorporeal medicine at that time were all positive displacement pumps. Mostly they were roller pumps, but some finger pumps were still in use. A typical roller pump is shown at right, above. A roller pump has two rollers that compress or “milk” the fluid in a section of tubing (the pump “shoe” or “raceway”) by either completely occluding or almost occluding the tubing (Figure 1). They will thus pump almost anything inside the tubing, including air. They also have another feature that can be deadly dangerous in extracorporeal medicine, and that is that if you occlude the outflow of the pump it will keep pumping and increasing pressure until, a) the motor is not powerful enough to continue pumping against the back-pressure, or b) the tubing and/or components in the circuit between the pump and the occlusion explode or come apart (disconnect, or “blow-off”).  One other disadvantage is the action of the rollers on the tubing raceway cause it to spall, or to shed microscopic bits of plastic debris into the blood, and thus into the patient (if not intercepted by the arterial filter). These pumps, despite their seemingly overwhelming disadvantages, were the standard in cardiopulmonary bypass (CPB) until very recently.  And they are still widely used – and they still predominate in the Third World.

Figure 2: Comparison of flow/pressure curves of centrifugal and positive displacement pumps.

While centrifugal pumps have great safety and efficiency advantages, they have some nettlesome downsides. Chief amongst these was that a shaft to drive the impeller had to penetrate the pump housing (left in Figure 1, above) and that meant you needed a seal. This caused all sorts of problems when handling a sterile fluid like blood, and a fluid which could tolerate no contamination. Seals are a source of friction, and thus of particulates. Centrifugal pumps are also almost impossible to adequately clean, and tubing in a roller pump was disposable. Two other problems were that centrifugal pumps are notorious for causing cavitation in the fluid they are pumping. Because they can create regions of very strong negative pressure, they can cause gas bubbles to form – bubbles that subsequently embolize the patient’s circulatory system. The impeller from centrifugal pumps can also generate  enormous shear and turbulence in the liquid, and these cause hemolysis and damage to platelets and white blood cells.

It took decades to design centrifugal pumps that could handle blood “atraumatically,” and when this was finally accomplished, centrifugals performed better than roller pumps under laboratory conditions (there is very little difference clinically in terms of neurological outcome). Since there is no compression of friable tubing in centrifugal pumps, there is also no spallation of plastic particles into the blood. Finally, centrifugal pumps, unlike roller pumps, do not have any rigorous correlation between the rpm of the drive motor and the flow output of the pump. Instead, flow output is a complex function of rpm, torque and back pressure – and so is the developed pressure in the system.  You can see this in Figure 2, above. What this means in practice is that you must have a flow meter to actually measure the flow the pump is producing at any given time. This wasi pretty easily accomplished in industrial applications n the 1970s (and before) by using paddle-wheel, falling ball, or other kinds of in-line flow metering devices. But these solutions don’t work well, or in most cases at all, for blood.

By contrast, every turn of a roller pump will deliver a fairly predictable and uniform bolus of flow. To know your flow, all you have to do is to count the number of rpms, and multiply that number by the volume of fluid displaced with revolution of the rollers. In the early days of CPB, you had to do this by using a “look up table” to convert rmps to flow, based on the diameter of the tuning you were using in the pump head. It was simple, easy and foolproof, but could be dangerously distracting. In the late 1970s, little calculating devices with LED displays did that work for you, and look-up tables taped to the front of the pump console disappeared.

Figure 3: A magnetically-driven, seal-less, injection molded, disposable polycarbonate centrifugal blood pump head.

By the 1980s, huge advances in manufacturing technology made the magnetically-driven, seal-less, injection molded, disposable polycarbonate centrifugal pump head, similar to that shown in Figure 3, not only possible, but economical. Now, the impeller could be driven via magnetic coupling, and no shaft or seals were necessary. Cleaning wasn’t an issue because the whole thing could be thrown away after it was used. And the cost had come down to about $200 per pump head.  Technological advances in “non-wetted” flow measurement made electromagnetic flow meters not only practical, but affordable. So, the flow measurement problem was pretty much solved, as well.  Later, the advent of ultrasonic Doppler flow measurement technology, made flow measurement even more cost effective and accurate.

Why not use these pumps for cryopatients?!!? Unfortunately, it is a characteristic of both electromagnetic and ultrasonic flow measurement devices that the physical properties of the liquid whose flow is being measured matters.  Electromagnetic flow meters only work if a solution has ions or some other magnetic field distorting property – such as being slurry of metal dust, or containing a ferromagnetic molecule…  The washout and cryoprotective perfusion solutions used in cryonics have low concentrations of ions – most of the salts have been replaced with sugars or mannitol (a sugar-alcohol). What’s worse, the concentration of ions will vary wildly and dynamically as perfusion proceeds, because the salts (ions) in the patients’ tissues are being washed out.  Indeed, this is why the more proper name for perfusion to do “blood washout” is called “Total Body Washout (TBW),” because it is not just the blood that is being washed out, but also, to a significant extent, the very chemical composition of the patient’s extracellular space.

Ultrasonic flow meters are intolerant of the huge changes in the micro-particle concentration and the viscosity of the perfusate that occur during TBW and cryoprotective perfusate.  These flow meters are calibrated and optimized in design around blood – and both extracorporeal ultrasonic and electromagnetic flow meters caution the user that they cannot be used with blood containing less than 10 or 20% red blood cells (red cells are, of course, loaded with iron containing hemoglobin, and they scatter ultrasound).  Thus, measuring flow under conditions of TBW and cryoprotective perfusion has proved an intractable problem for over 35 years.

Figure 4: The Manrise model 101 Flow Inducer developed by Fred Chamberlain, the first cryonics perfusion machine, used a Cole-Parmer., Inc., Micro Pump centrifugal pump with a magnetically driven stainless steel and ceramic pump head as the “flow inducer.” A Dwyer Instruments, Co., falling ball flow meter, an in-line analog thermometer, and a sphygmomanometer (connected to a bubble trap) was used as the pressure gauge.

Ironically, given Maxim’s vitriol over cryonicists being “ignorant of centrifugal pump technology,” the first “perfusion machines” developed for cryonics used centrifugal pumps. And that meant they had to have a flow meter.  After much (costly) testing, we settled on a falling ball flow meter, because it performed relatively well across the range of viscosities of perfusates we were using. But please note, this machine was build only for open-circuit perfusion, and blood, even in very small concentrations, renders a solution opaque. If you can’t see the ball, you can’t read the flow… Also, we still had to make look-up tables for each concentration of cryoprotective perfusate to be perfused because falling ball flow meters are sensitive to liquid viscosity.

Figure 5: Extracorporeal Life Safety System (ELS) Bubble Detector and Tubing Clamps for Roller Pumps. http://www.rockymtresearch.com/els.htm

The ELS is an air in line detection safety system indicated for use on roller pump bypass circuits. If air in line is detected both automatic tubing clamps and auditory / visual alarms are activated. The device includes a third clamp for the bridge loop incorporated into roller pump circuits. The Bridge Clamp opens if the line clamps are activated to prevent excessive pressure in the circuit.

Product features include:

  1. Bubble detection: designed so that bubble detection sensitivity can be set down to 10 uL.
  2. Bridge Clamp: The bridge clamp will open the instant air is detected and the patient clamps close. This creates an open circuit to prevent pressure build-up.
  3. Automatic bridge-line “flash”: The bridge clamp can be set to periodically open and flush the bridge line. Duration and interval controls are located on the front panel of the device. Patient clamps remain open during bridge flash cycle.
  4. Manual override on all clamps (all three clamps cannot be closed simultaneously).
  5. Dry-coupled transducer.
  6. Internal battery back-up with automatic recharge.
  7. Compatible with any system.
  8. Simple controls and user interface.

The ELS device has FDA clearance and has been certified by CSA to the IEC 601-1 and UL 2601-1 standards for electrical safety.

___________________________


Figure 6: LevelSens, a level sensor and detector, notifies operators of low fluid levels in either flexible or rigid reservoirs. Having both medical and industrial applications, the level sensor will alarm audibly and visually when the fluid reservoir level drops below the user-placed sensor and will cease alarming when the fluid level returns. The device does not need to be reset and there is no pump interaction. http://www.rockymtresearch.com/levelsens.htm

  • For Any Flexible or Rigid Fluid Reservoir.
  • Functions on Both Blood and Priming Fluids.
  • Reliable and Simple to Use.
  • No Conflict with Other Devices.
  • Increases Safety. Limits Liability.
  • Powered by a 9 volt Battery.
  • Self Stick, Disposable Sensors.
  • CE Marked

_

There are two control modules: one designed for use on rigid fluid reservoirs, one designed for flexible fluid reservoirs.

The LevelSens has FDA clearance and has been certified by CSA to IEC 601-1 and UL 2601-1 standards for electrical safety. An independent evaluation has been done by Rocky Mountain Perfusionists of Denver, Colorado. (see abstract)

PRODUCTS:

  • LevelSens – Rigid (Model #201070 for use on rigid reservoirs)
  • LevelSens – Flexible (Model #201110 for use on flexible reservoirs)
  • Disposable sensors – Package of 25 (Product #201073)
    For use with either LevelSens Rigid or Flexible systems. Each package contains 25 individual disposable sensors for use with either the rigid or flexible LevelSens Safety System.

In the intervening decades since this problem was first encountered I, and others, have repeatedly looked at the issue of how to reliably measure flow in perfusates that are dynamically varying in red cell content, ion content, cryoprotective agent content (and thus viscosity) and in temperature (which affects viscosity and  often the performance of the flow meter transducer, as well). I think I have found the solution to the problem (last year, in fact), but for now, I’m keeping it to myself. And when I say found it, I mean just that – I didn’t invent it – it’s yet another artifact of technological advance inflow measurement.

One other problem with medical centrifugal pumps is that they cannot handle the very high viscosity, low flow, terminal phase of cryoprotective perfusion. The pump motor controller is not built to operate under such conditions, and the magnetically coupled impeller will, if the viscosity of the perfusate is too great, simply uncouple from the drive shaft magnet and stop turning.

Because of these issues, and especially because of the flow measurement issue, I recommended that centrifugal pumps not be used for cryonics applications at that time. Yet another reason for my doing this, and feeling comfortable with the safety issues, is that there are now rock-solid, reliable extracorporeal (FDA approved) monitoring systems for both air, overpressure, and reservoir fluid level, which will shut down the roller pump and clamp the blood conducting lines within ~ 300 msec of detecting a problem (Figure 5). The latest generation of low reservoir sensors will work on virtually any kind of plastic reservoir (hard or soft) and are insensitive to the type of fluid being used or to the temperature (down to  ~ -5oC) (Figure 6). Thus, despite their disadvantages, roller pumps still trump centrifugals because it easily possible to reliably and dynamically know the flow being delivered to the patient – and that is critically important.

This is an example of an area where expertise in cryonics, related to the application of extracorporeal  medicine, is critical. Medicine does not smoothly map onto cryonics, and this true not just in extracorporeal medicine, but across the board.  A consequence of this is that if you try to take a physician, a surgeon, a perfusionist, or a paramedic, and simply “dump” them into the cryonics arena, they will typically make very serious errors. This is to be expected, because any specialized area of technology, be it medicine, engineering or computer programming, has its own unique operating parameters and its own unique set of specialized requirements and skills. Cryonics is properly a highly specialized branch of medicine, just as are neurosurgery and cardiac surgery. It is grossly unfair to both cryonics, and to medical professionals, to behave otherwise.  I think that Maxim both refuses to believe this is so, and finds it highly offensive, neither of which change the reality of the situation.

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Response to Maxim’s Rant about Automation in Cardiopulmonary Bypass http://chronopause.com/index.php/2011/02/26/response-to-maxim%e2%80%99s-rant-about-automation-in-cardiopulmonary-bypass/ http://chronopause.com/index.php/2011/02/26/response-to-maxim%e2%80%99s-rant-about-automation-in-cardiopulmonary-bypass/#comments Sun, 27 Feb 2011 06:42:18 +0000 admin http://chronopause.com/?p=332 Continue reading ]]> By Mike Darwin

“Off with their heads!

Off with their heads!”

That’s what Melody Maxim says!

The Queen of Perfusion?

No, that’s just a delusion

And once you read this

There will be no confusion!

A creature right out of Alice in Wonderland, Melody Maxim is the Red Queen of Perfusion, condemning any and all to death, who dare to disagree with her.

Eine Kleine Nachtmusik

I loathe the use of the ad hominem in arguments, and the proof of this is that I rarely use it (and much of what I’ve written is on-line, so this statement can be easily checked). I feel this way about it because I’ve so often had it used on me. My secondary school years, particularly the first two, were horrible. They took the concept of bullying to a whole new level. My response to this was to keep as low as profile as possible, and to go out of my way not to get beaten up – either verbally or physically. It didn’t work. While I can’t say I was grateful for the experience, I did learn a lot from it, not the least of which was the understanding that there isn’t just one type of “bully” or “harasser.” They come in a variety of phenotypes and they are often motivated by very different things.

I also learned that the old axiom about sticks and stones and broken bones is a bold faced lie. Words can and do hurt, and it is a disservice to tell people being injured by them that they are of “no consequence,” or should be allowed to “roll off their backs like water off of a duck’s back.” And so we come to Meoldy Maxim, and the others like her who persist in attacking and threatening cryonicists. There is no reasoning with her, and even honestly agreeing with her on many of her criticisms regarding the poor standard of care in cryonics has no effect. In fact, even having made many of the same criticisms, both before and after her entry into cryonics, has no effect (for example see: http://www.network54.com/Forum/291677/thread/1233270318/Request+for+clarification+from+Melody+on+disagreements+with+Mike+Darwin+%28loose+thread%29).

Two of her favorite hobby horses to ride on her attacks on cryonics are that cryonics has never used extracorporeal medical technology, and that cryonicists misrepresent themselves as medical professionals. I, and many others in cryonics have been the subject of countless electronic and media articles over the years. These reports usually open with, or quickly get to, “the fact that the people performing these (cryonics) procedures are not doctors or, in most cases, nurses…etc.” The reporters writing these stories do this for two reasons: 1) because they were told what the qualifications (or more properly, the lack of medical/professional qualifications) of said staff were, and 2) because it makes cryonics seem less credible and more controversial. I have never misrepresented myself as other than what I am, and aside from that being something that seemed the moral and commonsense thing to do at the time, it has also proved to be especially wise in this era of collapsed privacy, and easy access to all manner of information via the Internet. So, it is actually possible to check on these things, and if you want to fess up the money, you can retrieve those countless newspaper and magazine articles.

But that is not satisfactory to Maxim:

http://www.cryonet.org/cgi-bin/dsp.cgi?msg=32645:

“I think it damages the credibility of cryonics organizations, to represent staff members as medical professionals when they are not. In fact, I am often tempted to argue it is a form of consumer fraud. It doesn’t take much common sense to  know that people interested in cryonics, who view photos of people appearing to  be performing surgical procedures, while dressed up in medical garb, and being  referred to as “surgeons,” “perfusionists,” or other specific medical  professionals, will be left with the impression these people have the  appropriate qualifications, to be referred to as such. It would be extremely difficult for me to believe that the people behind those photos and case reports were not fully aware of this.”

Yes, it is certainly true that cryonicists have referred to the positions on the cryopreservation team by the medically descriptive names, such as “surgeon” for the person who performs, well performs what? Cannulation? No, that’s a medical term, too. And it is equally true that mostly the folks at Alcor and BioPreservation (when it existed), wear surgical gowns and that we always used scrub clothes, drape sheets and other “medical attire” and accoutrements. We did so and do so for the same reason that medical professionals do – to protect the staff, as well as the patient from pathogens. Sometimes, we don’t use surgical gowns, because the risk of infectious disease (Hepatitis C with other viral co-infection) makes biohazard-grade Tyvek coveralls a better option. Maxim wants cryonics to be completely staffed by medical professionals and to use only FDA approved medical technology and devices, and yet she vehemently objects when, in fact, a Board Certified perfusionist is “pumping the case” and a licensed physician is performing the surgery and a licensed scrub nurse is handing off the instruments and a respiratory therapist is operating the blood gas equipment.

For myself, I’d be fine with assigning made-up, or de novo names to each of the people who perform the tasks of scrub nurse, surgeon, circulator, perfusionist… as well as creating new garb. The fact is, it never occurred to me or to Jerry Leaf to do so – we were too busy trying to apply medicine to cryonics. In the 1920’s and ‘30’s one of the greatest surgeons who ever lived, Alexis Carrel (he developed the definitive technique for anastamosing severed blood vesels, thus making transplantation of solid organs possible) fancied the garb you see in the photo below. Carrel believed that sunlight corroded the brain, and that that was why, “The world’s great civilizations have formed far above the equator, where there is much less direct sunlight than in tropical regions.”

Alexis Carrel with an assistant operating his black operating room, dressed in his black surgical garb at the Rockefeller Institute in the first decades of the 20th century.

But not only wouldn’t that satisfy Maxim and her ilk, it would simply give her (and the rest of the world) additional ammunition to label cryonics a cult. And even I have to admit that the picture of Carrel above, is pretty kooky. So, we come to at least the second lesson about a bully like Maxim, and that is that you are damned if you do, and damned if you don’t. Use medical equipment and wear protective medical garb (which also happens to be sterile and very low in shed particulates) and you are perpetrating consumer fraud. Fail to do these things and you are a quack. It matters not at all that you have consistently, and for decades, carefully explained that you are not Board Certified medical professionals. And if you do, in fact, follow Maxim’s suggestions and, for example, hire the very per diem perfusion service she her self suggested be retained, well, then you are still an incompetent fraud trying to bilk an unsuspecting public of their money.

Harm does not just involve the public’s reaction to these posts by Maxim, and others. It can and does involve the devastating impact on the people within cryonics, as well. Men who are professionals, who I interface with in critical care medicine, and who have seen the material Maxim, et al., have written, have remarked that they would never get involved in cryonics, if for no other reason than that they would not want their current or future employers seeing things like “fuckpipe,” “animal torturer,” or “murderer” come up on a Google search of their name. In a world full of competent people looking for jobs, which one would you pick if your job was on the line for the downstream consequences of making the ‘wrong’ choice in an employee, strictly from a PR standpoint, and leaving competence out of it. Just log on to Cold Filter (http://www.network54.com/Forum/291677/) and look at Maxim’s rants. Yes, those posts are certainly going to make it a lot easier for the medical professionals she claims she wants to populate cryonics, to get involved.

What makes her approach particularly vicious is that virtually from the day cryonics was born, it has been impossible to get those kind of professionals involved on any consistent, reliable or adequate basis, because the majority of the population thinks the idea of “freezing dead people to be brought back to life in future centuries when they can be cured” is barking mad. And they still do. And that attitude had (and has) nothing to do with how cryonics is practiced, then or now. Certainly, progress has been made, in that I no longer have people faint or vomit when the idea is proposed by one of its practitioners (things that happened to me twice in the course of polite party conversation in the 1970s), and there is no longer the rabid response of nihilistic young ecofreaks, “that the world will be destroyed by overpopulation from cryonics if it works and how dare we…” The world is already well on its way to destruction by overpopulation, completely absent any help from cryonics; sanitation and vaccination were more than enough to do the job.

One of the many things I’ve learned from all of this is that peoples’ opinions about cryonics are shaped to an astonishing degree by rumors and hearsay. This is so because cryonics is not accepted and is not a topic of mainstream coverage in the media, or in medicine or government, and therefore it is also exempt from the corrective mechanisms that are normally present in these spheres.

If someone were to credibly, for instance, say that Brad Pitt was a Satanist (i.e., not the National Enquirer), an entire set of powerful mechanisms stands ready and waiting to both refute and punish them, if what they say is both taken seriously, and is not true. And while most average citizens don’t know these mechanisms exist, they do know that such statements are not to be taken seriously unless some sort of consensus is present in society. Also, and this is very important, the average person actually (usually) cares enough to ask that critical follow-up question, “How do you know he is a Satanist?” He cares, because if true, that’s an incredibly socially valuable piece of information to him, personally. He can then tell his friends at work, his wife and his golfing buddies, “Hey, did you know Brad Pitt is a Satanist! Yeah, there’s a shocking video on Youtube, made by one of his former nannies, of him sacrificing little African babies in a Satanic Ritual!”

Of course, if there is no Youtube video, or other credible evidence, such remarks will be dismissed as coming from a nut, or some kind of lunatic who has a fixation on Brad Pitt. By contrast, cryonics is in the unfortunate position of already being considered suspect, and cryonics is also of no consequence to 99.99…% of the population. Therefore, negative remarks further degrading its reputation count vastly more.

When I visited Dearborn Village outside Detroit, MI many years ago, I got lucky, because a Lincoln Scholar from the University of Illinois was giving a guest lecture in Lincoln’s relocated courthouse, which is part of the Village campus (Henry Ford did all this in homage to Edison, Lincoln, and others he admired). The topic of his lecture was Lincoln’s law practice, and his legal experience as a rural lawyer. As it turns out, the vast majority of Lincoln’s cases were libel and slander torts. The reason for this was that people at that time and in that place, had almost no assets. They had few chattels, and even less cash. The nature of the communities in rural Illinois was such that they were both small and geographically remote from each other. Farmers, craftsmen and professionals would thus service a large, but sparsely populated area. All these people had were their reputations (and no, or very little savings to fall back on); and this at a time when much more mattered than if you were competent. If you were said to be an adulterer, a Catholic or a Jew, or any of a thousand other ‘bad’ things, well, you were very likely to find yourself with no livelihood. Scandal meant something in those days, and it didn’t have to involve having 6 mistresses, or engaging in endless nights of cocaine and prostitute filled revelry. All that was required was to be morally purblind or, heaven forbid, even a little dishonest.

That is what is happening to cryonics, and I know this to be so when a respected cardiac surgeon in INDIA, who knows me only via the web, drops me a note saying, “Mike, I was under the impression you guys in cryonics used CPB technology…what is this all about?” At least he asked. Most wont.

The Bard said it best in Othello:

“Iago:

Good name in man and woman, dear my lord,
Is the immediate jewel of their souls.
Who steals my purse steals trash; ’tis something, nothing;
‘Twas mine, ’tis his, and has been slave to thousands;
But he that filches from me my good name
Robs me of that which not enriches him,
And makes me poor indeed.”

Response to Melody Maxim

In a message dated 1/23/2011 2:00:09 A.M. Pacific Standard Time, owner-cryonet@cryonet.org writes:

Message #33264
From: “Melody Maxim” <perfusion333@comcast.net>
References: <20110122100001.21427.qmail@rho.pair.com>
Subject: In Response to Mike Darwin’s “Automated Data Collection” Post…
Date: Sat, 22 Jan 2011 15:31:09 -0500

MM: It is absurd for Mike Darwin to maintain that cardiovascular perfusion is “very simple to automate compared to some of the unbelievably complex and exacting manufacturing processes (he’s) seen automated.. It can be surprisingly difficult, even if you have you have experts, and enormous computing power at your disposal.” [sic] (*Note: Mr. Darwin refers to cardiovascular perfusion as “cardiovascular bypass,” terminology that might be confusing to some, as indicated by Perry Metzger’s Cryonet response to Mr. Darwin, in which Mr. Metzger appears to be asking if Mr. Darwin is referring to automating an entire cardiovascular surgical procedure. (Cryonet message
33257))

MD: First, if you want to have a respectful technical dialogue you should, a) be sincerely interested in a dialogue, and b) treat your correspondent respectfully. Words like “absurd” and “arrogant” don’t work anywhere in any forum of debate or discussion; with the possible exception of politics and religion – and neither are under discussion here. If you can’t do that, you will either need to go elsewhere, or you will get no response from me, or most others here.

While it is technically correct to use the words ‘cardiovascular perfusion,’ (since the circulatory system may also properly be referred to as the cardiovascular system), the more correct terminology is ‘cardiopulmonary perfusion.’ However, even t hat term is a bit of a misnomer, because during much of the interval when perfusion is carried out during cardiac surgery (its most common indication) the pulmonary circulation of the lungs is, in fact, poorly perfused and usually not perfused at all. This is because the patient’s heart is arrested with cardioplegia (to allow the surgeon to work on it with greater ease and to spare its high energy reserves) and the right ventricle is unable to perfuse the pulmonary circulation. The lungs do have a separate parenchymatous circulation, and this does continue to be perfused in most clinical settings where CPB (cardiopulmonary bypass) is employed. However, under low flow/low pressure conditions, lung parenchymal perfusion may be absent, or reduced to trickle flow.

MM: It’s nonsensical to assert that something “very simple” is at the same time “surprising difficult,” even in the hands of experts with unlimited  technological resources. Even more than that, it is preposterous to compare the manufacturing of a specified component, or device, which requires the same, precise, repetitive steps, time-after-time-after-time, to the perfusion of human beings.

MD: Yes, it would be nonsensical to assert those things if I had said what were being attributed to me. But in fact, I did not say “unlimited technological resources,” because, to the best of my knowledge, no one has those at their disposal; and I did not compare automating CPB to ”the manufacturing of a specified component, or device, which requires the same, precise, repetitive steps, time-after-time-after-time.”

The difficulties of automating CPB relate to its dynamic nature, the complexity of the controlling decision tree required, and to the ‘dynamic rates of change’ nature of many of its features – the latter of which are addressed in mathematics by the calculus. Having said that, CPB is, in fact, fairly straightforward to automate (within limits) when compared to other complex procedures that have been automated. A wide range of manufacturing processes involve similarly nettlesome problems with regard not only to change in pressures, volumes and flows, but also with respect to the rapid addition and removal of heat (again, a rate of change of problem). And while many of these processes do involve very uniform systems, some do not.

Landing jetliners, contrary to MM’s assertion, is in fact a good example of this, because this task is every bit as complicated as perfusion, if not more so. Computerized control of landing requires enormous integration of data from multiple control surfaces on the aircraft under widely varying conditions; and in fact, not only widely varying conditions, but dynamically varying conditions. With automation, it is possible for aircraft to do things that no human pilot ever could.  For example, at airports equipped with category IIIc ILS (instrument landing system) aircraft can use their ‘autoland’ function to land in zero visibility conditions.1 That’s mind blowing when you think about it: 500 lives hurtling at 200 miles per hour toward a runway that no one can see, with no pilots touching the controls, and with the safe bump of landing gear on the pavement being the first clue that the ground has been reached. Under such conditions, rates of change problems become paramount, just as they do in CPB. And, I would be the first to admit that I had absolutely no idea that this would be the case when I set out to undertake this task (in conjunction with others blessedly more knowledgeable than me).

MM: Responding to Mr. Darwin’s automated airplane/perfusion analogy, it doesn’t
matter WHY the wind blows, or WHY the terrain rises, it only matters that the plane must maintain its center of gravity and stay above the terrain. However, it DOES matter why venous return to a heart-lung (perfusion) machine diminishes. Did the patient’s blood vessels dilate, resulting in more volume remaining in the patient, and less returning to the machine? If so, the proper response might be administering vasoconstrictors. Is the surgeon pulling the heart over, so that he can work on the posterior side, temporarily interfering with the venous return to the machine? If so, the
proper response is to temporarily adjust the flow rate, provided that doing so does not result in the patient being inadequately perfused. Has something happened, which resulted in an unexpected loss of blood, from the patient, or perfusion circuit? If so, that situation needs to be recognized and corrected, immediately, and volume must be added to the system, to replace that which has been lost. (This discussion is simplified, and intended to be for an audience of laymen. There are many factors, in regard to both the causes, and the responses, to such a situation.) If the returning volume is suddenly depleted, does the computer have discussions with the anesthetist and the surgeon, to determine the cause of, (and, therefore, the proper response to), such a situation? This is only one example of MANY issues, which perfusionists must respond to, on a case-by-case basis; a situation that precludes the use of fully-automated perfusion systems. There is nothing in the perfusion process, similar to the precise manufacturing of components, or devices, no matter how complex that manufacturing might be!

MD: Now, we are onto the real issues here. As a matter of fact, it does matter WHY the wind blows and WHY various control surfaces (and the aircraft’s position) respond as they do, and for much the same reasons as changing physiological parameters matter in CPB. If descent is a little faster than predicted, is it because the ailerons are not responding appropriately, the air density is unexpectedly low (low barometric pressure), or the engine speed is inadequate - or because any or all of these values are being reportedly incorrectly?

This is what the ‘control center’ (formerly the engine room) of a contemporary state of the art cruise ship or large cargo vessel looks like:

Engineering control room of a modern, computer controlled cruise ship (L).

Virtually every function of the ship is automated and requires ‘only’ intelligent oversight. As is the case in CPB, many of the systems within the ship are in continuous, dynamic interplay with each other – as is also the case in living organisms. These systems are increasingly being merged – with water distillation for bathing and cleaning being integrated with heat exchange operations, such as cooling the generators that provide power, not just for the ship’s electrical systems, but for the azipods[1] that are now rapidly replacing propellers and diesel engines. I could go on for pages about large ocean vessel automation; I’ve been all through these kinds of vessels, and sat for hours on the Bridge and in the engineering (or control room: engine room is passé). In many ways, these systems dwarf automation in aviation because pretty much the entire ship’s systems are now under computer control – the generators, electrical load management, azipods, heating, cooling, water and waste processing, are dynamically controlled by computers.

Since these systems are increasingly integrated and interdependent for increased energy efficiency, they behave much like physiological systems. For instance, if you are moving waste water around to treat it for discharge and/or reprocess it for cooling the generators’ engines, you will likely affect the CG of the ship, as well as its hydrodynamic behavior. Of course, sea conditions can do this, as well as fuel use, movement of cargo or ballast, and so on. The computerized systems integrate all this data and seamlessly adjust the ship’s stabilizers, azipods and other control mechanisms to compensate – as well as dynamically adjust the ballast. Each seagoing vessel also has a transponder which continuously broadcasts a unique identifier number, which includes the vessel name, type of cargo, destination, course and current heading (among other things). All of this data is displayed on flat screens on the Bridge in real time, and the on board computers can and do, dynamically adjust the course to avoid collisions.

Cruise ships, in particular, are very sensitive to any disturbance which could cause passenger discomfort. They also have a highly mobile cargo, massively complex infrastructure (they are actually self contained cities, much like long-haul star ships) and they consume enormous amounts of power for refrigeration and HVAC. All of this is managed by process control systems that dwarf CPB in their complexity, and in their criticality to human life.2 Spend a few days with unfettered access on a state-of-the art container ship and cruise ship (the latter should be at least Panamax class, and preferably built within the past 10 years).  Each is impressive in its own unique way, and each represents a pinnacle of automation and technological achievement that I think very few people understand exists.

Similarly, the Bridges of large, state-of-the-art cargo ships are almost completely automated and typically require the oversight of no more than 2 men at one time – an incredible feat of programming and engineering. And when I say oversight, I mean just that – mostly the First Officer and Captain sit and do paperwork. The degree and sophistication of automation required to operate such a ship, largely absent human intervention, dwarf the automation of CPB at a comparable level of oversight.

Automated Bridge of a contemporary state-of-the-art large container (cargo) ship.

Changes in physiological parameters can indeed have multiple causes, and may in fact occur because several very different mechanisms are at work at the same time and are interacting with each other! Arterial pH is a fairly straightforward example to use. If a patient’s pH declines to a level deemed unacceptable, it could be due to any of the following things (at a minimum): inadequate ventilation (which in turn could be due to inadequate O2 delivery and/or inadequate CO2 removal by either the gas blender or due to failure of the oxygenator), global hypo-perfusion, regional hypoperfusion, administration of large volumes of low pH parenterals (typically IV fluids), and so on. If you want an automated system to control patient pH dynamically, that system has to be imbued with both the tools and the intelligence to discriminate amongst the possible causes, determine which causes are operational at the moment, and act to intelligently correct them.

Such correction may entail more than one intervention since the ’cause’ of a drop in arterial pH may be due to several causes – although usually this is not the case. And this complex interaction becomes greatly amplified when it is understood that pH effects vascular tone, and thus can cause vasodilatation, resulting in decreased mean arterial pressure (MAP, blood pressure), or the converse. Any robust automated system has to be able to look at the ‘big picture’ and make the correct adjustments. These things I understood very well when I began the effort. However, what I did not understand was the ‘invisible experience’ that most humans have when it comes to dealing with dynamic systems where rapidly varying (and recursive) rates of change of are involved. This is hard for me to explain, but I’ll do my best.

When I first sat down with a couple of clinical perfusionists and began to work on this project, the thing we all ’missed’ at first, is that you cannot just specify ‘high’ and ‘low’ numbers for things like arterial and venous pressures, or for arterial flow, at which point the machine will ‘act’ by adjusting said pressure or flow to the desired value. In other words, you cannot just program in ‘alarm limits’ to which the machine will respond. It turns out that most such corrections to physiological parameters are made more or less unconsciously, and are based to a significant degree on the observed rate of change, and even on the shape of the curve of the rate change!

Central venous pressure and pulmonary artery pressure proved particularly difficult to control because they must be kept low (in absolute terms), there is very little range to work with, and they may vary based upon a number of interacting factors, some of which can change with incredible rapidity (i.e., the venous return line from the patient becomes suddenly occluded). If you wait to intervene until some ‘target’ number is reached, you will almost always over- or under-shoot, and the same will be true of subsequent efforts to correct the pressure and return it to the desired range: thus, a vicious circle of positive feedback results. As it turns out, this is a common problem in process control, and there are program algorithms to deal with it. The standard algorithm used for process control is something called PID, which is short for Proportion/Integral/Derivative control.3 This means that in, say, controlling pump speed to maintain a target perfusion pressure, the system will look at three things: How far you are from the target pressure (‘proportional’), how fast to incrementally change the pump speed to approach the target pressure (‘integral’), and how fast the target pressure is being approached (‘derivative’).  The art of process control is in tuning the values of these three parameters so that targets are reached and maintained as quickly as possible, and without overshoot.

Thus, I learned that a lot of what constitutes ‘gaining experience’ in things like perfusion, or piloting aircraft, is learning to apply corrections that, while they may seem ‘set point’ driven, are, in fact, very complex responses to equally complex changes in a dynamic system.

MM: Perfusion IS automated, to a large degree. Perfusionists can program their machines to respond to various parameters, in a variety of ways. For example, the machines can be made to automatically adjust flow rates, in response to pressure; or to turn off a pump and clamp the patient lines, in the event of inappropriate pressures, or air in the lines. But, what happens after that?

MD: I would hardly consider such simple control any kind of high order automation. Here we touch upon another issue: the degree to which you wish to automate perfusion or perhaps more accurately, the scope of automation that is being pursued. Nowhere in what I wrote did I suggest (or even imply) that the level of automation we were pursuing would replace a knowledgeable person. In fact, I was at pains to point out that this was not the case; at least not with the resources (or objectives) at our disposal 15 years ago! While our objectives were indeed daunting, they comprised only a small subset of the requirements that would pertain in an operating theatre, where ’perfusion’ might consist of a routine CABG, a double valve replacement, or resection of a brain aneurysm under deep hypothermic circulatory arrest.

What we were aiming for (and largely achieved) was a system that could initiate CPB in an animal (dog) after ~15 min of normothermic circulatory arrest, restore both cardiovascular and basic metabolic homeostasis (pH, A&V blood gases and regulate blood glucose), and induce hypothermia to a pre-specified degree. An additional (non-CPB related) requirement was the controlled and feedback-driven administration of a number of cerebroprotective drugs – some of which perturbed MAP.

MM: Someone, who knows how to assess the situation, and produce the proper response, must be operating that machine. I find it quite arrogant, for Mr. Darwin to claim he has tried to automate perfusion systems and has found it difficult. Does Mr. Darwin think he compares to the scientists, perfusionists and engineers, involved in equipment development, with the major manufacturers of perfusion equipment? While I’m sure Mr. Darwin has toyed with primitive perfusion equipment, at cryonics facilities, he is not a perfusionist, or an engineer, and he certainly does not have resources
comparable to those of companies, which specialize in perfusion equipment, such as those mentioned here: http://www.perfusion.com/cgi-bin/links/default2.asp?tree=558

MD: As I pointed out earlier, our efforts were undertaken 15 years ago. Having said that, yes, we were in fact working with state-of-the art equipment where that was possible and appropriate. For instance, we did not try to build our own gas blenders, blood pumps, reservoir level sensors, or ultrasonic air bubble detectors. Where it is possible to use a developed and reliable commercial product, only a fool or a very poor (and/or desperate) person chooses to do otherwise. We were neither that foolish nor that poor. We used costly state-of-the art LabView data acquisition and process control hardware and software as opposed to trying to do our own programming or solid state electronics design.

Automating basic cardiopulmonary bypass in the late 1990s at 21CM. Today, the process control and computing equipment occupying the panel rack at the left of the photo above would fit easily into a space about the size of two laptop computers – and still have capacity to spare!

However, it should be remembered that in much of the world people are desperately poor, and they must ‘engineer on the fly’ if they are to survive.4,5 They often do so, and in fact, more often than not they do so with stunning efficacy. I’ve seen plastic soda bottles used as re-useable re-breathing reservoirs in patients getting O2 therapy, soda bottles used with aquarium frits as humidifiers on ancient (but working) ventilators, and CPB performed where the same blood filled circuit and oxygenator (sans filter) are used on 3 successive patients (with compatible blood type and cross match). Are these things desirable? Of course not, and they carry risks that would be completely unacceptable here in the developed world, where I happen to be at the moment. But, to patients who are confronted with otherwise certain death, and to their treating physicians who have no other alternative, these kinds of compromises save lives – a lot of lives. Similarly, in most Third World countries, many disposable medical devices are reprocessed and reused – often many times – with little or no downside. Disposable oxygen masks, nasal cannulae, O2 conductive lines, suction lines and canisters, and many more devices can be safely and reliably reused providing good protocols for doing so are in place, and well trained people inspect the end product.

As to interfacing with the manufactures of perfusion hardware and disposables, I was lucky to count as a colleague the then CEO of Gish Biomedical, who was incredibly generous with disposable components, and who provided access to his engineers at no cost during this project. Ditto Sarns. These companies were interested in what we were trying to do and they provided as much informal support as I could have wished to have. In fact, it was from these people in industry that I was first acquainted with the real problems that stood in the way to developing this technology, problems I didn’t understand, because I lacked their enormous expertise and, more importantly, experience with the commercial and regulatory environment. While I lacked these things, I didn’t lack the wisdom to go in search of them elsewhere.

Before FDA regulation of medical devices (which is comparatively recent), the barriers to doing something like automating CPB to the extent we trying to achieve would have been far lower, if for no other reason than that the interface of hardware, software and drug delivery components would not have been subject to FDA vetting.6 This raises the cost of approval considerably. Additionally, the then (and now) current market for in-field CPB, using automated systems, is virtually non-existent. As was pointed out to me, even if 20,000 cases per year presented (about 10% of the sudden cardiac death population in the US at that time) it would still be uneconomical. And indeed, when 21CM ultimately began licensing discussion with Pharms for the cerebroprotective regimen we had developed, the projected marketplace, when considered in the context of the certain regulatory approval costs, was deemed way too small.

While 150,000 or even 250,000 patients/year may seem like a lot, it really isn’t when you consider that the complex technological platform of multiple novel drugs, and sophisticated hardware and software would only be used, on average, ONCE by each patient who needed them. Development and regulatory costs for drugs are now so high that big Pharma has concentrated its efforts primarily on drugs that will require extended, or preferably life-long use (i.e., psychiatric drugs, dyslipidemia drugs, antihypertensives…)  and on drugs that will command large reimbursements because they deliver comparably dramatic results (such as Gleevec and other targeted ‘molecular therapeutics’ for cancer).7

MM: Darwin wants to argue that such automation could require less-skilled personnel, something I find disturbing. Someone who does not routinely assemble and operate perfusion equipment is very unlikely to be able to assess, and correct, problems that might occur with an automated-system failure. Would Mr. Darwin like someone who has memorized the contents of a dozen aviation textbooks, but never flown an airplane, to be sitting in the cockpit of his commercial airliner, when the computer goes out? I find his argument for “knowledge without reflexes” being “sufficient,” (in regard to cardiovascular perfusion and flight), to be absolutely ludicrous.

MD: Given the statement above, Maxim may soon have to give up flying altogether,  because not only are most commercial jetliners piloted most of the time by computers, the latest generation of high performance aircraft cannot even remain in the air without them – pilot or no pilot. The advent of highly reliable automation has led to the design of aircraft that are inherently unstable. In other words, these aircraft must be provided with continuous and very complex adjustment to their control surfaces to remain airborne; so called fly by wire (FBW) control. Examples of such aircraft are the F-117 Nighthawk and the B-2 Spirit flying wing.

The Grumman X-29A is an example of an extremely inherently unstable aircraft whose design elements may soon be adapted for civilian use.

Piloting inherently unstable aircraft is so complex and difficult a task that human beings cannot do it. High performance aircraft that have FBW controls (also called CCVs or Control-Configured Vehicles) may be deliberately designed to have low, or even negative aerodynamic stability in some flight regimes; in which case the rapid-reacting CCV controls compensate for the lack of inherent stability. The use of CCV technology allows for a large weight reduction in the aircraft by eliminating most of the hydraulic and electromechanical controls formerly necessary, and it dramatically reduces the workload and fatigue of the flight crew. Yet another powerful advantage in this era of skyrocketing fuel prices is that CCV technology increases fuel efficiency by optimizing control of the aircraft and by eliminating ‘pilot induced oscillations’ which negatively impact fuel consumption. So powerful is CCV, that an entire book has been written credibly suggesting that pilot Sully Sullenberger’s ‘miraculous’ emergency landing of that US Airways Airbus A320 on the Hudson river after it was disabled by geese entrained in the engines, was not so a much a miracle as an artifact of CCV technology (see Fly By Wire: The Geese, the Glide, the “Miracle” on the Hudson by William Langewiesche)! An interesting interview with Langewiesche on his book is available here: http://www.amazon.com/Fly-Wire-Geese-Miracle-Hudson/dp/0374157189.

Coming down the pipe are the Intelligent Flight Control System (IFCS) which NASA-Dryden demonstrated as workable in 2002.8 The IFCS allows the aircraft to continue in flight and lad safely even after serious damage to the aircraft control surface or airframe damage would normally render the flight control system’s worthless, or put less politely, no longer controllable by a human pilot. IFCS uses neural network technologies with state-of-the-art control algorithms to correctly identify and respond to changes in aircraft stability and control characteristics, and immediately adjust to maintain the best possible flight performance during such failures. The neural network computer and software ‘learns’ the new flight characteristics of the damaged aircraft in real time, ‘helping’ the pilot to maintain or regain control and prevent a catastrophic failure. This system has succeeded in landing severely damaged aircraft in testing.

As to Maxim’s statement that my “argument for ‘knowledge without reflexes’ being “sufficient,” (in regard to cardiopulmonary perfusion and flight), to be absolutely ludicrous,” the answer is, “Not at all.” I assume that Maxim has not pumped a case in some time, in which case she is just such a person as I describe; she has knowledge, but not reflexes. The same would be true of a race car driver who has not raced in 6 months (or maybe less!) or a pilot who has not flown for a year. Maybe one of the best examples I can offer is that of a ‘retired’ gymnast or ballerina who teaches these arts. Physiological limitations related to aging make the careers of these people extremely short. In the case of gymnasts, their careers are pretty much over by their early to mid-20s. They have the knowledge, but they no longer have the ‘reflexes,’ or even the physical ability to perform. However, they make superb instructors, and they can detect errors with great speed. But more importantly, they have the ‘meta-knowledge’ that the novice does not have. That is what I meant by ‘knowledge without reflexes.’ I know very well that I would experience an unacceptable failure rate if I were to walk into an OR and try to do CPB on a research animal under demanding conditions after 10 years away from doing CPB at all. Indeed, I would want to start out slowly, and partner with an up-to-speed perfusionist before I ‘soloed’ again. I assume the same would be true of a clinical perfusionist who had long been away from the OR.

The advantage that a well automated CPB system provides is that it allows the skilled person to focus on the use of his high order knowledge without being occupied with housekeeping tasks. In fact, it was for just this reason that automated piloting and landing of jetliners was developed. This technology was not developed in order to let pilots wander about the cabin chatting with passengers while the plane was being landed. Nor was it developed to cover the contingency that the pilot and copilot might both be dead or disabled, or that the pilot and co-pilot might be in a particularly compelling discussion about scheduling, and allow the aircraft to fly blindly on past its destination by hundreds of miles, as happened recently. Rather, it was developed for just the reasons I’ve laid out here.

Our incentive to develop this technology at 21CM was that the interventions required for restoring homeostasis, rapidly inducing therapeutic hypothermia after prolonged cardiac arrest and simultaneously administering over a dozen different drugs, were simply beyond the ability of humans – any humans, to carry out reliably. There are some things people can’t do, even in medicine, and as a consequence we see the advent of robotic surgeons, IV fluid administration systems that can shape the curve of a drug dose and impose periods of ‘ramp and soak’ that would require the full time attention of a human, and still be done badly. There are even programs that alert physicians and pharmacists to medications conflicts as they write prescriptions, because humans are miserable at remembering such information.

Perhaps the best example is one of the simplest. With the advent of mild therapeutic hypothermia (MTH) as the internationally recognized treatment of choice for post cardiac arrest encephalopathy, it is now necessary to impose ~3 deg C of hypothermia with very tight control of temperature for 12-24 hours post-insult, followed by controlled, slow re-warming to normothermia.9,10,11,12 Note that while there is only one parameter to control in this system (temperature) – humans are horrible at it – even if you set one person full time on these two tasks. It also turns out that simple ‘set point’ systems, like those present in most medical cooling blanket systems which use feedback from the patient in the form or rectal or esophageal temperature, are also awful at tight temperature control. Such systems routinely over- or under-shoot the required temperature, and as a consequence, much more sophisticated devices, such as the Arctic Sun (external) and the CoolGuard (intravascular) clinical hypothermia systems which use complex algorithms to impose and maintain MTH, and carry out re-warming, have been developed, and are finding clinical acceptance.13,14,15,16

Humans are simply incapable of the precision process control required for things like imposing artificial temperature homeostasis in critically patients without the assistance of automation.

MM: Mr. Darwin’s remarks about a market not existing, for automated perfusion,
resulting in “no economies of scale…that further drives up the price and  drives down the reliability of any system you do develop,” is just as ridiculous as most of his other observations and speculations. The perfusion disposables I used two decades ago, cost approximately $1,600; today, the same disposables are around $500. I’m not a financial expert, but the machines, themselves, seem not to have increased more than that due to ordinary inflation. If there has been an increase, it has probably been due to the developments in the computerization/automation features! Salaries also seem not to have risen, other than increases due to inflation, over time. Never before has perfusion been so technologically-advanced, reasonably-priced, or safe. It is much more likely that heart surgery will eventually be performed, without the use of perfusion, than with the use of fully-automated perfusion, as evidenced by an ever-increasing number of
“off-pump” procedures. (Of course, this has nothing to do with cryonics. Heart surgery can sometimes be performed, without the use of perfusion, but the vitrification of human bodies cannot.)

The tipping point as to when a technology becomes cost effective and viable to use is one upon which fortunes are made and lost – and not just in medicine. Fully automated CPB will require the development of very sophisticated AI and robotics; and I don’t see that as being around the corner. As MM points out, in the 15 years since we undertook our pilot project, there have been incremental (but important) advances in the ‘automation’ of CPB – but these are almost exclusively concerned with discrete safety issues, as opposed to a more global management of the integrated procedure. Personally, I think perfusion would benefit from a far higher degree of automation, just as the airline industry has. People don’t do well at boring, repetitive tasks, like steering a jetliner (continuously) across the country. It’s better and safer to use them for what they are still currently the best at – meta-level, high order judgment and reasoning. Of course, when a jet liner goes down, it is big news and many people die very publicly and at once. Errors in the OR are not such big news…

Beyond that, in-field automated CPB is currently a product in search of a market that can enable and sustain it. The development of such a market will (IMHO) likely be incremental, and be driven by things like MTH, the approval of effective drugs for post-ischemic brain rescue, and so on. When it becomes clear to a broader cross section of clinicians and business people that a lot of lives can be saved (or enough), and that there is money to be made, then such technology may be developed. Still, arguably the greatest barrier to application of essentially ‘immediate’ in-field CPB is the problem of vascular access. Even with the advent of compact, hand-held imaging devices that allow for non-invasive (or minimally invasive) vessel location, and a growing array of percutaneous vascular access devices, this enabling part of CPB still requires a lot of skill and knowledge which are time consuming to apply, and are also not likely to be automated soon.

MM: The fact that Mike Darwin is one of cryonics’ greatest “superstars” should be quite telling. How many cryonics projects have been directed, on the advice of Mr. Darwin and others like him? How many of those projects were based in ignorance of existing equipment and technology? For so long as people like Mr. Darwin and his peers are considered to be “experts,” in cryonics experiments, there is likely to be nothing more than ample misdirection and false promises. It seems a very small group of self-interested people have made, what could be an interesting scientific experiment, a total sham. (By “self-interested,” I do not mean people who are interested in extending their own lives; I mean people who are primarily interested in maintaining their over-inflated egos and/or bank accounts, by maintaining control of experiments and/or projects, which they are not capable of leading.)

When Maxim writes, “How many cryonics projects have been directed, on the advice of Mr. Darwin and others like him? How many of those projects were based in ignorance of existing equipment and technology?” she should put up or shut up. How about a list of these projects that I have directed, or advised be undertaken, and that have demonstrated such ignorance, and proved so useless? Note, I am not asking for a list of such projects by ‘others like me,’ but rather, of projects for which I have been personally responsible.

I don’t consider myself a ‘superstar’ at anything, and as near as I can tell, that judgment is widely shared (and is especially fervent within) the cryonics community. However, I also don’t think that most of what I did in my years of working in and on cryonics, or biomedical research, was based on ignorance of existing medical technology. Indeed, often the reverse was the case; the technology simply didn’t exist (and often still doesn’t exist), or the medical community, primarily treating physicians (as opposed to drug or device makers), were either ignorant of the benefits of an emerging technology, or were actively opposed to its use (mostly as a result of prejudice and laziness).17 This was certainly the case (and still largely is) with MTH, as just one example.

Willem Kolff’s prototypical dialysis machine: what would Maxim have done to Kolff – especially when consideration is given to the fact that all 17 of Kolff’s first patients died – many as a direct result of complications from the treatment?

In the particular case under discussion, automated (or more properly, partially automated emergency in-field CPB), the then extant manufactures of CPB equipment and consumables were both interested in, and supportive of our efforts, because they all began themselves in pretty much the same way, operating under pretty much the same conditions. Willem Kolff made his first clinical dialysis machine from a custom fabricated enamel pan, a Ford fuel pump (used to circulate the dialysate), unpainted wooden slats and sausage casing (which he passed the patient’s blood through).18 I knew Kolff personally, and there was nothing he would NOT use in medical device fabrication if he thought it was the best item for the job.

C. Walton Lillehei, and his beer tubing and industrial finger pump heart-lung machine, in the early 1960s.

The early days of CPB were characterized by the in-house fabrication of MOST of the equipment that was used and that had blood contact, and a wide variety of common household and industrial items were pressed into service. The first clinically applied bubble oxygenator was made from PVC tubing used in beer breweries (the DeWall oxygenator) and C. Walton Lillehei began the University of Michigan’s stellar cardiac surgery program using this oxygenator, and a hemolysis inducing peristaltic finger pump made by the Sigmamotor Company, for industrial applications!19 It was a long hard road from the beer tubing oxygenator above to the first commercially produced Travenol disposable bubble oxygenator below.

The Travenol DeWall bubble oxygenator marketed in the mid-1960s.

It took the better part of a decade for manufactures to enter the field, like PEMCO in 1961, and a bit later, Dick Sarns, who founded Sarns, Inc. Before that, surgeons, and their nascent perfusionists fabricated their own hardware.  Maxim should read G. Wayne Miller’s superb biography of Lillehei, King of Hearts: The True Story of the Maverick Who Pioneered Open Heart Surgery, ISBN-10: 060980724 , J. Stewart Cameron’s, A History of Dialysis, ISBN: 0198515472, and David Monagan’s, Journey into the Heart, ISBN-10: 1592402658. Monagan’s book is a fascinating exploration of the development of cardiac catheterization and it brilliantly captures how even such recently such developed medical technologies are initiated using commonplace and often crude materials to fabricate truly revolutionary medical devices.

No doubt, Maxim would have stomped down these innovations in their infancy – particularly CPB, since coronary artery bypass grafting (CABG) was inferior to medical management of coronary artery disease in terms of survival until the 1980s, and arguably was not proved otherwise until the Veterans Affairs Cooperative Study of Coronary Artery Bypass Surgery for stable angina was published in 1992!20 Indeed, even the most recent studies show CABG benefits only patients with > 50% stenoses in their left anterior descending coronary arteries (LAD), or a “LAD equivalent” stenosis (> 70% stenoses of both proximal LAD and proximal left circumflex arteries), and in 3-vessel disease in terms of improved survival over medical management. 21,22,23,24 When consideration is given to the fact that the one of the most recent studies of the neurological injury that attends CPB demonstrated a ~50% incidence of both functional and structural neurocognitive injury as a result of CPB,25 one must wonder what Maxim would have to say about her own career, if it happened to belong to someone else?

Even more to the point, both established pharmaceutical and medical device companies are increasingly relying on tiny start-ups and entrepreneurs to do the hard and mostly unrewarding work of finding and developing new products that will actually be viable. Big companies in the US are awful at identifying and developing fundamentally new technologies, and the emerging pattern is for such large companies to either license, buy the new technologies they ultimately market from small start-ups – or to buy the new companies outright.

It’s ironic that Maxim chose to label me, of all people in cryonics, as being ignorant of CPB technology, let alone of failing to use it. As soon as such technology became affordable I used it, and in fact, it was Jerry Leaf and me, who, in the face of considerable criticism from the cryonics community, introduced virtually every element of CBP technology into cryonics that was appropriate (some items, such as large reservoirs to hold CPA solutions were (and are) not medically available). The proof of this is in the case histories published by Jerry and me, and later by me of cases I presided over after Jerry’s cryopreservation.

What is the basis for such an outrageous claim by MM? The answer: there is clearly none whatsoever.

[1] Azipod is the registered brand name of the ABB Group for their azimuth thruster. Originally developed in Finland jointly by Kvaerner Masa-Yards dockyards and ABB, these are marine propulsion units consisting of electrically driven propellers mounted on a steerable pod.

Selected Bibliography

1)    Langewiesche, W. Fly by Wire: The Geese, the Glide, the “Miracle” on the Hudson. Farrar, Straus and Giroux, November 2009, 208 pp, ISBN: 0374157189.

2)    To get some idea of the staggering complexity of the automation required to manage a modern cruise ship you can take a peek inside Royal Caribbean’s ship, Freedom of the Seas, here: http://www.youtube.com/watch?v=YY-3fipCTDw&feature=related. It is due in large measure to this automation that luxury is affordable (and hence possible). Consider that ~$100/day it is possible to dine on gourmet food 24 hrs/day, enjoy live theatre, water sports, and just about every other amenity imaginable, and to do so while at sea! It is passing impossible to find an average hotel room on land in or around any big city for $100 a night – and that does not include food, entertainment, gym facilities, gaming, and excursions – all you get is place to sleep and clean up.

3)    Bennett, Stuart (1993). A history of control engineering, 1930-1955. IET. p. p. 48. ISBN 9-780863412998.

4)    Borst, HG. The hammer, the sickle, and the scalpel: a cardiac surgeon’s view of Eastern Europe. Ann Thorac Surg 2000;69:1655-1662: http://ats.ctsnetjournals.org/cgi/content/full/69/6/1655. Retrieved 2011-01-29.

5)    Bokeria L.A. History of cardiovascular surgery. Moscow: Bakoulev Scientific Center for Cardiovascular Surgery, 1998.

6)    Higgs, R. Wrecking ball: FDA regulation of medical devices. Cato Policy Analysis #235, August 7, 1995. http://www.cato.org/pubs/pas/pa-235.html. Retrieved 2011-01-30.

7)    DiMasi, JA, et al. The price of innovation: new estimates of drug development costs. Journal of Health Economics 22 (2003) 151–185. http://cryoeuro.eu:8080/download/attachments/425990/CostOfNewDrugDevelop2003.pdf.

8)    NASA  – NASA Dryden Fact Sheet – Intelligent Flight Control System: The Intelligent Flight Control System (IFCS) flight research project at NASA Dryden Fact Sheets. Text Size. Grow Text SizeShrink Text Size. 02.13.06 http://www.nasa.gov/centers/dryden/news/FactSheets/FS-076-DFRC.html.

9)   Nolan JP, Morley, PT, Vanden Hoek, TL, et al. Therapeutic Hypothermia After Cardiac Arrest: An Advisory Statement by the Advanced Life Support Task Force of the International Liaison Committee on Resuscitation. Circulation. 2003;108:118 – 121.

10)  Hypothermia after Cardiac Arrest Study Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest. N Engl J Med. 2002; Feb 21;346(8):549-56. Polderman, Kees H. “Application of therapeutic hypothermia in the ICU.” Intensive Care Med 2004;30:556-575.

11)  Bernard SA, Gray TW, Buist MD, Jones BM, Silvester W, Gutteridge G, Smith K. Treatment of comatose survivors of out-of-hospital cardiac arrest with induced hypothermia. N Engl J Med. 2002;346(8):557-63.

12)  Arrich J, Holzer M, Herkner H, Müllner M. Hypothermia for neuroprotection in adults after cardiopulmonary resuscitation. Cochrane Database Syst Rev. 2009;7;(4):CD004128. Review. PubMed PMID: 19821320.

13)  Haugk, Moritz et al. “Feasibility and efficacy of new non-invasive cooling device in post resuscitation intensive care medicine.” Resuscitation. 2007;75, 76-81.

14)  Hoedemaekers, CW, Ezzahti, M,  Gerritsen , A, van der Hoeven, JG. Comparison of cooling methods to induce and maintain normo- and hypothermia in intensive care unit patients: a prospective intervention study. Crit Care. 2007; 11(4): R91. Published online 2007 August 24. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2206487/pdf/cc6104.pdf. Retrieved 2011-01-31.

15)  Treatment of fever in the neurologic intensive care unit with a catheter-based heat exchange system. Diringer MN. Critical Care Medicine 32: 559-564, 2004.

16) Efficacy and Safety of Endovascular Cooling After Cardiac Arrest: Cohort Study and Bayesian Approach. Holzer M, Mullner M, Sterz F, Robak O, Kliegel A, Losert H, Sodeck G, Ray T, Zeiner A, Laggner AN. Stroke 37: 1792-1797, 2006.

17) Wolfrum S, Radke PW, Pischon T, Willich SN, Schunkert H, Kurowski V. Mild therapeutic hypothermia after cardiac arrest – a nationwide survey on the implementation of the ILCOR guidelines in German intensive care units. Resuscitation.2007;72(2):207-13.

18)  Cameron, JS. A History of Dialysis. Oxford University Press, September 2002, 368pp. ISBN: 0198515472.

19)  Miller, W. King of Hearts: The True Story of the Maverick Who Pioneered Open Heart Surgery. Three Rivers Press; 2nd edition (February 1, 2000), 302pp. ISBN-10: 0609807242.

20)  Eighteen-year follow-up in the Veterans Affairs Cooperative Study of Coronary Artery Bypass Surgery for stable angina. The VA Coronary Artery Bypass Surgery Cooperative Study Group. Circulation. 1992;86:121-130.

21)  Sharma GV, Deupree RH, Luchi RJ, Scott SM. Identification of unstable angina patients who have favorable outcome with medical or surgical therapy (eight-year follow-up of the Veterans Administration Cooperative Study). Am J Cardiol. 1994;74:454-458.

22) Scott SM, Deupree RH, Sharma GV, Luchi RJ. VA Study of Unstable Angina. 10-year results show duration of surgical advantage for patients with impaired ejection fraction. Circulation. 1994;90:II120-II123.

23)  Sharma GV, Deupree RH, Luchi RJ, Scott SM. Identification of unstable angina patients who have favorable outcome with medical or surgical therapy (eight-year follow-up of the Veterans Administration Cooperative Study). Am J Cardiol. 1994;74:454-458.

24) Scott SM, Deupree RH, Sharma GV, Luchi RJ. VA Study of Unstable Angina. 10-year results show duration of surgical advantage for patients with impaired ejection fraction. Circulation. 1994;90:II120-II123.

25)  Knipp SC, Matatko N, Wilhelm H, Schlamann M, Thielmann M, Lösch C, Diener HC, Jakob H. “Cognitive outcomes three years after coronary artery bypass surgery: relation to diffusion-weighted magnetic resonance imaging.” Ann Thorac Surg. 2008 Mar;85(3):872-9.



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The Lifebridge B2T® “Plug-and-Play” Extracorporeal Life Support System http://chronopause.com/index.php/2011/02/25/the-lifebridge-b2t%c2%ae-%e2%80%9cplug-and-play%e2%80%9d-extracorporeal-life-support-system/ http://chronopause.com/index.php/2011/02/25/the-lifebridge-b2t%c2%ae-%e2%80%9cplug-and-play%e2%80%9d-extracorporeal-life-support-system/#comments Sat, 26 Feb 2011 03:42:50 +0000 admin http://chronopause.com/?p=302 Continue reading ]]> By Mike Darwin

Figure 1: The ultra-compact, lightweight and fully self contained Lifebridge B2T® Portable Extracorporeal Life Support System.

Introduction

The Medizintechnik GmbH Lifebridge B2T® extracorporeal life support system (Figure 1) is a device fast closing in on a technology I’ve long dreamed about, and even made some tentative efforts towards developing, namely, a compact, self-contained, field-able, semi-automated cardiopulmonary bypass system.1,2 It is a beautifully engineered and elegant little machine, and I believe that it represents (at least for Europe) the beginning of a transition of extracorporeal circulatory support (ECCS) from exclusive use in the operating theatre and ICU in the hands of perfusionists, to the hands of critical care and emergency medicine physicians and nurses in the Emergency Department (ED), in the Cardiac Catheterization Lab, and ultimately, in the field. It is also the latest extracorporeal technological tour de force from Germany, making that nation the world’s undisputed leader in innovative and brilliantly engineered ECCS products. As a useful aside, I would note that the first no-pump extracorporeal ventilator, the Novalung® iLA Membrane Ventilator (Figure 2) is also a product of German extracorporeal engineering.4-7

Figure 2: The Novalung® iLA GmbH Membrane Ventilator: no pump, no muss, no fuss.

When I first saw this system undergoing animal trials in Europe ~ 2 years ago, I was deeply conflicted about reviewing it anywhere that cryonics organization personnel might see my post. Historically, there has been this thirst for the “big technological fix” in cryonics, and I could see in my mind’s eye the cash changing hands in the eager hope that the Lifebridge B2T® would make bypass foolproof and easy. No such system exists, yet. Nevertheless, the Lifebridge B2T® is unquestionably a big step along the way. The device contains a PC with sufficiently sophisticated software to allow the system to pretty much prime itself! But, I’m getting ahead of myself.

System Configuration and Performance

The unit consists of three proprietary integrated units which supply every hardware and disposable component needed for emergency cardiopulmonary bypass. The entire extracorporeal circuit is contained within an injection molded polypropylene housing that snaps easily into place. The Patient Module is incredibly rugged, and it can actually tolerate being flung on the floor with considerable force without damage to the bypass circuit components inside – although this practice is clearly not recommended. [When this was demonstrated for me it reminded me of when plastic IV bags were introduced as an alternative to glass bottles. Baxter sales reps stood on them, stomped on them, and flung them off multistory buildings!]

The components embedded in the disposable “Patient Module” consist of a 400 mL hard shell venous reservoir which feeds a clone of the Biomedicus BP80 centrifugal blood pump from which blood is delivered to the oxygenator/heat exchanger and arterial filter. The Lifebridge B2T®  was originally marketed with only the  Minintech BioCor 200 Polypropylene pseudomembrane oxygenator as an option, but Medizintechnik received 510(k) clearance in December of last year to begin offering the device with the Medtronic Affinity® NT oxygenator, with either Carmeda® Bioactive Surface coating, or Trillium Biopassive Surface coating. This makes the entire system completely “heparin bonded” and “blood compatible,” permitting minimal anticoagulation. The arterial filter is a Terumo Pall AL8 40 40-micron filter with an integral bypass loop. Also molded into cassette that holds the extracorporeal circuit are disposable sensors for monitoring arterial and venous pressure (including filter back-pressure), as well as sensors air for detection, and venous reservoir level monitoring and control.3

Figure 3: The disposable, integrated Patient Module which contains the entire extracorporeal system.

There is a small, integral (also disposable!) roller pump head in the patient module that semi-automatically primes the extracorporeal circuit with lactated Ringer’s solution, and assists in ensuring the system is de-bubbled and ready to connect to the patient (Figure 5). This little positive displacement pump is also used to control volume in the venous reservoir. Fluid waste is dumped to a waste reservoir which is also contained within the patient module cartridge and is vented to atmosphere via a 0.45 micron hydrophobic filter to prevent aerosol contamination of the ambient air. The extracorporeal system is closed to air – there is no blood-air interface in the system, and this further reduces trauma to the blood (hemolysis and protein denaturation) and provides added inherent safety against air embolism.

The second element of the system is the Control Module, which houses the drive system, (the blood pump motor/controller, the drive motor for the roller pump active air elimination system, the automatic clamps for blood flow regulation, and an integrated back-up Lithium Polymer (LiPO) battery that allows standalone operation of the control and patient module. The entire system, including the transport case “suitcase” that the unit can be fielded in weighs ~20 kg. The (required) 1 liter of Ringer’s solution prime is not included in the system’s weight. Minus the carrying case, the system comes in at a weight of 18 kg (39.6 lb) – very impressive considering that the device subsumes a conventional extracorporeal membrane oxygenation (ECMO) cart and part of a perfusionist. Occluding clamps and all other instrumentation needed to safely operate the system are either integral to the device, or included within its transport case. The extracorporeal cartridge can safely remain in the system for 1-year after it is emplaced – further reducing the time from deployment to fully operational status. I was able to go from dry to primed in 6 minutes, and the manufacturer says it is easily possible to do so in 5. I believe them. The modular configuration and semi-automatic priming of the system allows for what is being termed “plug-and-play” initiation of ECC within 5 minutes.1

Figure 4: The semi-automatic priming procedure requires the pump head to be manually rotated 90 degrees so that the pump inlet is pointing up (at left, above). Once the circuit is primed, the pump and circuit are rotated in the operating position shown at left in the schematic above..Centrifugal pumps are inherently incapable of pumping macro-air because they de-prime when large amounts of air enters the pump head. The Lifebridge B2T® has cleverly built on this inherent safety feature by mounting the centrifugal pump head with its tangential outlet pointing down.1

The third component of the system is a base module with a tubular tilting frame that allows the machine to be rocked back 90 degrees to permit priming. That’s the semi-automatic part of the priming process – although the unit walks you through it a step at the time (Figure 4). The base module is surprisingly well designed and is quite stable – the locking mechanism is intuitive, and the tubular framework is rugged, so it is unlikely to become bent or distorted from being lugged around or transported in vehicles or aircraft.  The base module houses the transformer and control electronics for charging the Bullith batteries,[1] and the unit will accept either 110 or 220 VAC current. The Bullith batteries are, again, an example of where German engineering and innovation are taking the lead – they are compact, featherweight by comparison to gel cells, they hold a lot of energy for their size and weight – and nothing else on the market comes close to their reliability and performance. They also have a fantastic shelf life and do not require continuous trickle charging to keep them from spoiling, as do NiCad and NiMh cells. That means you can leave the unit on the shelf, much like an Automatic External Defibrillator (AED), until you need it – and when you do need it, the Lifebridge B2T®  can run for an incredible 2 hours without mains power.

The control unit has a conventional PC embedded in it as the “brains” of the system and the interface is a very slick touch sensitive flat panel and a rotary switch. I think the most surprising thing about Lifebridge B2T® to me was the user-friendly hardware engineering, and the intuitive Graphical User Interface that “gets everything just right.” You see the data you need when you need it, and you find the controls displayed where you want them when you want them. The rotary switch to control the pump speed is an astonishing concession to practicality and ergonomics over the “dazzling” menu driven technology which seems to be mandatory on every new consumer or medical device. When I want to turn down, or shut off a blood pump in a hurry, I do not want to be searching around on a glowing gas discharge display screen for a “virtual knob”- I want something I can instantly find, grab hold of, and twist!

Perhaps years-long exposure to US-made computer games has finally warped the GeNext German mind into sensible and understandable engineering. The Germans have always been able to manufacture beautifully crafted and engineered devices – the problem has been their often byzantine and madly complex implementations (beware of German plumbing!). The onboard PC records and stores all the typically desired case data and perfusion protocols. Patient specific data input is simple and straightforward, and there were USB ports on the machine I saw for data import/export.

Figure 5: Schematic of the Lifebridge B2T® extracorporeal circuit. All of the components enclosed boxed area on the diagram are embed in the disposable, rugged and  impact resistant disposable Patient Module.

Applications

The system was designed primarily for Cardiac Catheterization lab or Emergency Department (ED) use by non-perfusionists to serve as a perfusion and oxygenation platform for patients who present in cardiogenic shock and who need the additional “time bridge” to get coronary revascularization via angioplasty, or coronary artery bypass grafting (CABG).8,9 It will also likely find ready application in treating profound hypothermia, where it is ideal for circulatory support and core rewarming. This is a significant issue on the Continent, where skiers and other winter outdoorsmen not infrequently experience exposure.

Figure 6: At top, Members of the 59th Medical Wing Extrcorporeal Membrane Oxygenation Support Team undergoing hands-on ECMO training during an exercise on July 1, 2009, at Wilford Hall Medical Center, Lackland Air Force Base, Texas. The ECMO machine is a portable extended use cardiopulmonary bypass device that circulates and oxygenates the patient’s blood allowing time for acute lung injury or ARDS to resolve and the patient to recover. The lower picture is the current patient and ECMO hardware support cart mounted in a C-17 cargo plane. Anything that can reduce the weight and complexity of the ECMO system is invaluable under such conditions and ultra-compact and automated systems would allow for immediate application in forward, near battlefield positions.

I’ve been told that the US military has purchased Lifebridge B2T® units to evaluate in planned expanded deployment of extended (ECMO) support in cases of acute respiratory distress syndrome (ARDS) secondary to polytrauma, blunt force cardiac trauma and blast injury to the lungs (now “new” wartime pathologies as a result of body armor ‘softening the blow’ of what would have been otherwise lethal projectile impacts and much improve on site and in-field critical care medicine). The center for the military’s use of ECMO is the 59th Medical Wing at Wilford Hall at Lackland Air Force Base, TX. The ECMO capability at Wilford Hall dates back to the work of Air Force physician Gerald Klebanoff who invented the total body washout technique for treating stage IV hepatic coma in the early 1970s.10,11,12 The military commitment to this technology seems serious,13and in fact the Wilford Hall crew just had their first successful ECMO mission transporting a critically wounded soldier from Afghanistan back to Germany and then to the US for definitive treatment using a by C-17 cargo aircraft to carry the ECMO cart (Figure 6).  This operation was planned, tasked, command and controlled by the 618th Air and Space Operations Center (AOC) at Scott Air Force Base, which is the principal US and NATO agency for worldwide military airlift, air refueling and aeromedical evacuation. The military is also beginning to use Novalung technology for acute stabilization and management of patients with respiratory failure secondary to battlefield trauma.14

The primary feature that will likely expand the use of CPB and ECMO into critical care and emergency medicine is the Lifebridge B2T®’s computerized “System for Prevention of Air Embolization (SPAE).” This system employs a 7-layer deep prevention protocol using an automatic “air management procedure” that is triggered by in blood macro and micro air detection employing an ultrasonic air bubble detector placed immediately after the arterial filter in the circuit.1 If bubbles are detected, the arterial line is closed within <300 msec by means of an arterial clamp (Figure 5, #1). By simultaneously opening, the arterio-venous (A-V) shunt line, which connects the arterial line (post filter) to the venous line (Figure 5, #2), blood containing micro- or macro-air is diverted to the venous reservoir without hazard to the patient. Once bubble removal is complete, the on-board computer closes the A-V shunt and unclamps the arterial line to once again begin perfusing the patient. The seven-stage SPAE operates as follows:

1) Air entering into the venous line, or re-circulating through the purge lines, rises to the top of the venous reservoir via the buoyancy effect, where the roller pump (Figure 5) actively removes it.

2) The venous reservoir employs a two compartment design separated by a120 micron membrane, or screen. One compartment handles the venous return, and the other serves as the sump from which blood is drawn for perfusion through the oxygenator and into the patient. The devising screen effectively excludes microbubble generated as a result of turbulence, negative pressure in the venous line, or air leaks around the venous cannula, from entering the arterial intake – in effect it is a pre-arterial filter microbubble filter – a very clever and long overdue safety feature.

3) Low venous blood level is detected by a sensor that immediately stops the pump. This system is fairly “smart” in that when I regularly interrupted venous return, the machine would shut down and re-start perfusion in a dynamic fashion in response to the blood level in the reservoir.

4) An inherent safety feature of centrifugal pumps is that they will not pump macro-air. The Lifebridge B2T® has cleverly built on this feature by mounting the centrifugal pump head with its tangential outlet pointing down, making it more difficult for any air entrained in the pump head to rise under the influence of gravity and enter the arterial line.

5) As is standard on all ECCS circuits, the oxygenator also serves as bubble trap and air can be eliminated by the automatic opening of the solenoid clamp on the oxygenator recirculation line, to divert flow to the venous reservoir where it can be vented or siphoned off as required.

6) Again, as is now universal practice, the arterial filter employs centrifugal air separation using spiral flow, and this air is continually eliminated from the circuit by a bleed line atop the filter, which is in turn controlled by the PC.

7) Whenever bubbles are detected behind the arterial filter, the “air management protocol” eliminates them, as previously described. All prevention measures are inherent in the configuration of the system except for 3) and 7) above, which are implemented in the control software by the PC.

The unit has no intrinsic heater/cooler, so an additional module to perform this function must be used if ECMO support is to go on for an extended period of time, or if rapid induction of therapeutic hypothermia is desired. The oxygenators used in this platform are all rated for 6 hour use, however, as any Third World perfusionist will tell you, in most cases they can be reliably run to 12 hours; and runs of 24 hours, or longer, are not uncommon. I would also note that if the era of profound or ultraprofound asanguineous hypothermic perfusion ever arrives in medicine, the useful life of microporous membrane oxygenators will be further extended, since the membrane retains its integrity much longer in the absence of both blood and normothermia. The Lifebridge B2T® system makes switching patient modules safe, rapid and easy, so in the event the oxygenator begins to weep transudate, clots too many fibers, or otherwise deteriorates in performance, switch-out is fast.

As with other Minimal Extracorporeal Circulation (mini-ECC) systems, the Lifebridge B2T® has superior blood handling characteristics. Due to reduced tubing volume there is correspondingly less prime needed, as well as a small reduction in the total surface area of foreign material that blood is exposed to, and thus less pro-inflammatory cytokine release.[2] The hemolysis characteristics of the system in clinical use are also, as expected, quite favorable, and there seems to have been no price paid for plumbing the system into such a constrained space.1

A testimony to the trust placed in the automated components of perfusion in the  the Lifebridge B2T® is evidenced by the fact that much of the extracorporeal circuit is no longer visible to the operator. I found this very disconcerting, until I grew to trust the device’s “management” of perfusion.

The Future

I have long believed that an essential technology to a truly field-able ECC unit that can be pressed into service the instant vascular access is achieved in the field, is a pre-primed circuit incorporating a true membrane oxygenator. Such a circuit would be stored ‘wet,’ and be fully primed and ready for connection to the patient as soon as vascular access was established. With the advent of yet another German advance in extracorporeal technology, the development of the poly-4-methyl-1-pentene gas exchange membrane, now available clinically in the Jostra Rotaflow and QuadroxD true membrane hollow fiber oxygenators, this dream seems closer to a reality.15,16 However, the Lifebridge B2T® is forcing me to rethink this “requirement.” By compacting and cleverly arranging the circuit elements, priming and de-bubbling are made much simpler. There is no longer any need to beat on the arterial filter with a rubber reflex hammer, or to chase air from pillar to post in the circuit during priming. The machine is essentially self-priming. The only reason Medizintechnik didn’t make the device completely automated for priming is that it would have required the incorporation of a heavy, motorized tilt assembly to rock the circuit from the operational position to the priming position, and back again. This would clearly have been a poor engineering decision when that operation is so easily accomplished by human hands already present (and required) to operate the device. In practical terms, 5 minutes from start to patient ready, might as well be “instantaneous,” because vascular access will invariably take longer, far longer, in fact.

And that is just about the last barrier to the deployment of ECC and ECMO technology into first responder applications. There is no question that very rapid ECC would be highly effective in improving the outcome in sudden cardiac arrest if it could be applied on site, with effective CPR, such as that offered by the LUCAS device, being used only as a brief bridge in the event of failed first responder defibrillation.17,18,19 With further automation of ECC to minimize the requirement for highly developed quick reflexes in the operator, and further encoding in the machinery the complex algorithms for managing perfusion, the primary remaining barrier (aside from cost), is the inability to achieve rapid vascular access using minimally skilled personnel. This barrier seems insurmountable, but then so did the barriers to the creation of a device such as the Lifebridge B2T® as recently as a decade ago.

Figure 7: An add-on cooling module using ammonium nitrate and water, similar to the technology used in “instant ice packs” or perflurochemical evaporative cooling as used in the RhinoChill, should easily be able to emergently reduce patient brain core temperature by ~ 3oC.

One last point seems worth making and that is, regulatory considerations aside, it is easily possible to envision a very compact and disposable eutectic heat exchange module that could interface with the Lifebridge B2T® for the induction of Mild Therapeutic Hypothermia (MTH) in the field. Since only a 3oC drop in brain temperature is required acutely in MTH, the use of chilled prime solution (with another liter of chilled Ringer’s given at the start of bypass), a pre-cooled Patient Module, and the addition of a eutectic heat absorbing source, such as ammonium nitrate activated by water, or an evaporative PFC azeotrope such as is used in the RhinoChill,20,21 it should be possible to induce MTH in the field, or en route to the hospital without recourse to ice, or heavy refrigeration systems.

References

1)  Mehlhorn U, Brieske M, Fischer UM, Ferrari M, Brass P, Fischer JH, Zerkowski HR. LIFEBRIDGE: a portable, modular, rapidly available “plug-and-play” mechanical circulatory support system. Ann Thorac Surg. 2005 Nov;80(5):1887-92. PubMed PMID: 16242474.

2) Krane M, Mazzitelli D, Schreiber U, Garzia AM, Braun S, Voss B, Badiu CC, Brockmann G, Lange R, Bauernschmitt R. LIFEBRIDGE B2T–a new portable cardiopulmonary bypass system. ASAIO J. 2010 Jan-Feb;56(1):52-6. PubMed PMID: 20051839.

3) Maunz O, Horisberger J, von Segesser L. Bridge to life: the Lifebridge B2T extracorporeal life support system in an in vitro trial. Perfusion. 2008 Sep;23(5):279-82. PubMed PMID: 19346266.

4) Camboni D, Philipp A, Arlt M, Pfeiffer M, Hilker M, Schmid C. First experience with a paracorporeal artificial lung in humans. ASAIO J. 2009 May-Jun;55(3):304-6. PubMed PMID: 19282751.

5) Kopp R, Bensberg R, Henzler D, Niewels A, Randerath S, Rossaint R, Kuhlen R. Hemocompatibility of a miniaturized extracorporeal membrane oxygenation and a pumpless interventional lung assist in experimental lung injury. Artif Organs. 2010 Jan;34(1):13-21. Epub 2009 Oct 11. PubMed PMID: 19821813.

6) Ricci D, Boffini M, Del Sorbo L, El Qarra S, Comoglio C, Ribezzo M, Bonato R, Ranieri VM, Rinaldi M. The use of CO2 removal devices in patients awaiting lung transplantation: an initial experience. Transplant Proc. 2010 May;42(4):1255-8. PubMed PMID: 20534274.

7) Fernández P, Muñoz P, Fischer D, Méndez F, Florenzano M, Valdés S, Parada MT, Fica M, Rodríguez P, Díaz R, Rufs J. [Bridge to lung transplantation with a novel pumpless lung assist device. Report of one case]. Rev Med Chil. 2009 Oct;137(10):1363-6. Epub . Spanish. PubMed PMID: 20011945.

8) von Segesser LK, Kalejs M, Ferrari E, Bommeli S, Maunz O, Horisberger J, Tozzi P. Superior flow for bridge to life with self-expanding venous cannulas. Eur J Cardiothorac Surg. 2009 Oct;36(4):665-9. Epub 2009 Jul 16. PubMed PMID: 19615916.

9) Jung C, Schlosser M, Figulla HR, Ferrari M. Providing macro- and microcirculatory support with the Lifebridge System during high-risk PCI in cardiogenic shock. Heart Lung Circ. 2009 Aug;18(4):296-8. Epub 2008 Aug 31. PubMed PMID: 18762457.

10)  Klebanoff G, Armstrong RG, Cline RE, Powell JR, Bedingfield JR. Resuscitation of a patient in State IV hepatic coma using total body washout. J Surg Res. 1972 Oct;13(4):159-65. PubMed PMID: 5078628.

11) Cline RE, Klebanoff G, Armstrong RG, Stanford W. Extracorporal circulation in hypothermia as used for total-body washout in stage IV hepatic coma. Ann Thorac Surg. 1973 Jul;16(1):44-51. PubMed PMID: 4721190.

12) Klebanoff G, Langdon D, Wilen S, Tobias H. Total-body washout in hepatic coma. N Engl J Med. 1973 Oct 11;289(15):807. PubMed PMID: 4728761.

13) Midla GS. Extracorporeal circulatory systems and their role in military medicine: a clinical review. Mil Med. 2007 May;172(5):523-6. Review. PubMed PMID: 17521103.

14) Bein T, Osborn E, Hofmann HS, Zimmermann M, Philipp A, Schlitt HJ, Graf BM. Successful treatment of a severely injured soldier from Afghanistan with pumpless extracorporeal lung assist and neurally adjusted ventilatory support. Int J Emerg Med. 2010 Jul 13;3(3):177-9. PubMed PMID: 21031042; PubMed Central PMCID: PMC2926866.

15)  Mongero LB, Brodie D, Cunningham J, Ventetuolo C, Kim H, Sylvan E, Bacchetta MD. Extracorporeal membrane oxygenation for diffuse alveolar hemorrhage and severe hypoxemic respiratory failure from silicone embolism. Perfusion. 2010 Jul;25(4):249-52; discussion 253-4. Epub 2010 Jun 21. PubMed PMID: 20566586.

16)  Horton S, Thuys C, Bennett M, Augustin S, Rosenberg M, Brizard C. Experience with the Jostra Rotaflow and QuadroxD oxygenator for ECMO. Perfusion. 2004 Jan;19(1):17-23. PubMed PMID: 15072251.

17)  Greisen J, Golbaekdal KI, Mathiassen ON, Ravn HB. [Prolonged mechanical cardiopulmonary resuscitation]. Ugeskr Laeger. 2010 Nov 15;172(46):3191-2. Danish. PubMed PMID: 21073835.

18) Larsen AI, Hjørnevik A, Bonarjee V, Barvik S, Melberg T, Nilsen DW. Coronary blood flow and perfusion pressure during coronary angiography in patients with ongoing mechanical chest compression: a report on 6 cases. Resuscitation. 2010 Apr;81(4):493-7. PubMed PMID: 20227005.

19) Wagner H, Terkelsen CJ, Friberg H, Harnek J, Kern K, Lassen JF, Olivecrona GK.Cardiac arrest in the catheterisation laboratory: a 5-year experience of using mechanical chest compressions to facilitate PCI during prolonged resuscitation efforts. Resuscitation. 2010 Apr;81(4):383-7. Epub 2009 Dec 14. PubMed PMID: 20007005.

20) : Boller M, Lampe JW, Katz JM, Barbut D, Becker LB. Feasibility of intra-arrest

hypothermia induction: A novel nasopharyngeal approach achieves preferential brain cooling. Resuscitation. 2010 Aug;81(8):1025-30. Epub 2010 Jun 9. PubMed PMID: 20538402.

21) Busch HJ, Eichwede F, Födisch M, Taccone FS, Wöbker G, Schwab T, Hopf HB, Tonner P, Hachimi-Idrissi S, Martens P, Fritz H, Bode Ch, Vincent JL, Inderbitzen B, Barbut D, Sterz F, Janata A. Safety and feasibility of nasopharyngeal evaporative cooling in the emergency department setting in survivors of cardiac arrest. Resuscitation. 2010 Aug;81(8):943-9. Epub 2010 Jun 2. PubMed PMID:20627524.


[1] Bullith Batteries, Ismaning, Germany

[2] The primary source of blood exposure to non-native surfaces remains the oxygenator-heat exchanger and the arterial filter, both of which have enormous surface areas which are necessary for them to perform their functions.

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A Brief Pictorial History of Extracorporeal Technology in Cryonics – Part 5 http://chronopause.com/index.php/2011/02/07/53/ http://chronopause.com/index.php/2011/02/07/53/#comments Mon, 07 Feb 2011 22:50:44 +0000 admin http://chronopause.com/?p=53 Continue reading ]]> By Mike Darwin

CPB at BPI

When I left Alcor and started BioPreservation, Inc., (BPI) in 1992, the same high standard of care was continued. Where there was adequate notice, cardiopulmonary bypass (CPB) was initiated in the home using mechanical cardiopulmonary support (CPS) as a bridge, and the quality of CPS was greatly improved by combining active compression-decompression CPS (ACD-CPS) with high impulse chest compressions. Again, Michigan Instruments was enlisted to build a pneumatically powered machine that could deliver this modality, and which could also eliminate the pauses in chest compression (and thus interruptions in blood flow), required to administer ventilations.37

Figure 45: Active Compression-Decompression High Impulse CPS machine first put into clinical application on 12 Dec 1995.

In-home CPB was continued until BioPreservation ceased operations in 1996.38 The original ECMO[1] cart developed by Jerry Leaf had many modifications and improvements added to it by the time it was retired, including a CDI monitor for continuous in-line arterial and venous pH and blood gases, a computerized ACD-HI CPS machine, and increased battery life and oxygen carrying capacity (see Figures 46 & 47, below).

Figure 46: MALSS being set up in a patient’s living room for in-home CPB on 12 December, 1995.

Figure 47: Patient undergoing in-home CPB following immediate post arrest support with ACD-HI CPS.

In cases where the patient was remote from BPI’s facilities in Southern California, and where in-home CPB[2] was possible, a Remote Standby capability was deployed. BPI maintained two fully equipped ambulances as well as two complete Remote Standby kits fully stocked with all of the hardware and consumables required to initiate CPB, as seen in Figures 48 and 49, below.39

Figure 48: CPB set-up deployed in the home of long time cryonicist and cryopatient Jerry White, in Northern California. Jerry was cryopreserved on 05 February, 1994.

Figure 49: Extracorporeal circuit and portable ice bath in position in Jerry White’s condominium in February of 1994.

As was the case during my time at Alcor, cryoprotective (CPA) perfusions at BPI continued to be carried out using standard extracorporeal technology with virtually all of the perfusion and monitoring equipment used having been made by well respected medical manufacturers.40-42

Figure 50: Experienced experimental animal perfusionist from UC Davis Veterinary School (under contract to BPI) withdrawing a perfusate sample for analysis during the cryoprotective perfusion of Jerry White in 1994.

Figure 51: Cryoprotective perfusion tableaux at BPI in 1994.

Figure 52: Cryoprotective perfusion circuit used for Jerry White at BPI in 1994. The only ‘non-medical’ pieces of equipment in the circuit are the perfusate reservoirs, and the magnetic stir stable and stir bar, used to mix the CPA concentrate with the recirculating perfusate; a requirement unique to human cryopreservation operations.

The same was true of the surgical instruments and cannulae used for cryoprotective perfusion. My philosophy was, from the beginning, not to re-invent the wheel and, wherever possible, to use existing hardware and existing technology. Aside from the commonsense and practical reasons inherent in such an approach, it offered the incalculable advantage of allowing me and my colleagues more time to spend on solving problems not yet solved, and, where necessary, to fabricate novel hardware for which there was a pressing need – but no supplier.

Figure 53: Some of BPI’s cardiothoracic instruments on the back table during the cryopreservation of Richard Marsh at BPI on 06 May, 1994.

Figure 54: Cannulae and tubing configuration (median sternotomy) employed at BPI (cryopreservation of Richard Marsh on 06 May, 1994).

Figure 55: Board Certified clinical perfusionist performing the cryoprotective perfusion of Richard Marsh at BPI on 06 May, 1994.

One of the more bizarre fixations to emerge in the recent criticism of cryonics is the notion that cryonicists have had no contact with extracorporeal medicine or professional Board Certified perfusionists. Nothing could be further from the truth. The first perfusions carried out at Cryovita were pumped by a Board Certified Perfusionist who was a former colleague of Jerry Leaf’s. This allowed Jerry to concentrate his efforts on surgery to cannulate the patient and prepare him for connection to the extracorporeal circuit. Jerry was himself a Board eligible perfusionist, with countless clinical hours, in addition to his research CPB experience; he was the primary perfusionist at the UCLA cardiothoracic surgery research laboratory, and he was a skilled ‘surgeon’ who instructed clinical cardiothoracic surgeons at UCLA during their residencies.

I put apostrophes around the word surgeon when using it to describe Jerry Leaf; because it has recently been has implied that the use of this word to describe the position of the person who performs ‘surgery’ on cryopatients constitutes ‘practicing medicine without a license’[3] and ‘misleading or defrauding the public by projecting an image of medical certification and licensure.’ Of course, nothing could be further from the truth, and both Jerry and I were always careful to state who and what we were – including the absence of doctorates, medical degrees, or professional certifications. In particular, I have been accused of passing myself off as a ‘nurse,’ and to have otherwise misrepresented my qualifications. This is a lie, pure and simple, and I have never advertised, nor allowed to stand, any notion than I am anything other than a secondary school educated man with 3 months of additional training as a hemodialysis technician.

I have also been ruthlessly honest about the near absence of my math skills (and abilities) and have been blunt that this defect alone would have precluded me from ever obtaining a Ph.D. in any science, let alone an M.D. While I wish I could have been better formally educated, I am very proud of what I have achieved absent a university degree, and I am very glad I persisted in my pursuit of the sciences. My achievements are what they are, and they have been extensively documented in writing; and most of that work is available on the Internet today. The reader may access these materials and judge for himself to what extent my work has merit.

Similarly, BPI employed two perfusionists: one a practicing Board Certified clinical perfusionist, and the other a highly skilled and very experienced research and clinical veterinary perfusionist who had trained and worked at the UC Davis School of Veterinary Medicine. One of these perfusionists was present at every case BPI pumped. Going beyond perfusion, it should be noted that both Jerry Leaf and I were, in cryonics terms, very successful at recruiting people into our cryopreservation teams who were licensed biomedical professionals.

At any one time, the teams had an RN, LVN, perfusionist, Medical Technologist, Respiratory Therapist or physician (and usually combinations of the aforementioned). Dr. Thomas Munson, now a patient at Alcor, was a physician-surgeon with many years of experience who scrubbed in on almost all Alcor cases from shortly after the time he was recruited as a member from a lecture I gave in San Diego, until (at least) after I left Alcor in 1991. Dr. Steve Harris, who became involved in cryonics after I contacted him about an article he had written in regard to aging in the early 1980s, was also a great source of expertise, and was not infrequently present at Alcor cryopreservations. One young man who literally showed up on our doorstep, Scott Greene, put himself through EMT[4] training and then worked as an EMT while he put himself through nursing school (he often had two jobs at a time). Scott was an integral and highly valued member of the team until I left, and he took work as an RN at far remove from Colton, CA where BPI was first located.

BPI and Alcor also employed several highly skilled professionals who were not directly involved in human medicine, but who were uniquely (indeed enviably) qualified to participate in cryonics cases. One of these was a veterinary cardiothoracic surgeon who made his living, in part, by implanting novel prosthetic heart valves, left ventricular assist devices (LVADs) and total artificial hearts  (TAHs) in sheep and cattle for long-term evaluation prior to human clinical trials. He was a superb cardiac surgeon and perfusionist with an enormous reservoir of experience – he had even done some of the chronic implants of the Jarvik TAH in calves. These people did not want to be publicly associated with cryonics for reasons that anyone who has read these recent attacks should readily be able to appreciate.

Finally, a word of caution: When confronted with evidence that is contrary to their stated opinions or conclusions, these critics have, in the past simply denied or redefined that evidence. A case in point is the photograph shown in Figure 56, below. This photo was originally included in a report that a former perfusionist who worked at Suspended Animation, Inc., received a copy of during her employ there. She subsequently stated on the Cold Filter cryonics discussion forum that this photo showed the presence of air in the extracorporeal circuit, in particular in the pump ‘shoe’ or raceway. If this was indeed the case, it would be indicative of gross incompetence on the part of the perfusionist – who in this case happened to be me.

Figure 56: Pump raceway showing serum separation from blood (arrow) following termination of active cardiopulmonary support in a canine resuscitation dog experiment conducted at 21st Century Medicine in the late 1990s.

I tried to point out that she was mistaken in her assertion, and that what she was stating was air, was in fact separation of the red cells from the serum due to sedimentation of the cells under the force of gravity. This could (and did) occur because the pump was shut off, and had been shut off for some time. In this model the animals were severely vasoconstricted at the conclusion of the period of post-ischemic extracorporeal support due to the administration of vasopressin, and it was not possible to return much of the blood present in the extracorporeal circuit until many minutes after the animal was weaned from the pump. As a consequence, blood remained in the extracorporeal circuit and was gradually re-infused into the animal as the vasopressin was metabolized, and the vasoconstriction subsided. During this period, red cells fall to the more dependant part of the circuit under the influence of gravity. This sedimentation of red cells was further enhanced by the presence of therapeutic drugs that elevated the sedimentation rate.

Figure 57: Air bubble in silastic tubing during cryoprotective perfusion of a cryopatient in 1975. The high surface tension of water causes the bubble to have spherical contours as consequence of its interaction with air at the air-liquid interface.

In point of fact, it is a bit surprising that a perfusionist, whose attitude and remarks would appear to indicate she is all knowing on any subject related to CPB, would not know that water has enormous surface tension, and thus water-air (or blood-air) interfaces exhibit a meniscus, as can be seen in Figure 57, above. Not only is there no meniscus in the tubing in Figure 56, close inspection reveals that sedimentation is also underway (though much less complete) on the side of the tubing raceway that is on the opposing side to where it was asserted there was a large amount of air present (i.e., the right side). Yellow tinged serum can be seen to be appearing in this tubing; although the degree of red cell sedimentation is not as pronounced.

To sum up, this new generation of cryonics ‘critics’ has no sincere interest in improving cryonics, or in helping cryonicists. It is unfortunate that the first contact with cryonics for some of these individuals has been with utterly incompetent practitioners of cryonics.  Much of the criticism of SA that been leveled at the operation during the period of (at least) 2006-7 were, in my opinion, valid – and I say this based on firsthand experience as an unpaid consultant to SA in 2006. However, it is even more unfortunate that these critics went no further, and that they have based their evaluation of the use of extracorporeal technology in cryonics during the period from 1981 to 1995, as practiced by Jerry Leaf and I, based on their adverse experience with institutions where neither Jerry or I had any authority or responsibility.

This in no way constitutes an excuse for their indiscriminate reign of terror – indeed, my first experience of perfusion in cryonics was unarguably vastly more shocking and at variance with anything even remotely resembling medicine. I could have responded with irrational and non-constructive criticism, but instead, I responded by documenting what I found and putting forth every bit of effort I could muster to change things for the better. And above all, when I had the good fortune to encounter others in cryonics that were both competent and committed to doing the same, I had the good sense to set my ego aside and go to work with them in attempting to make cryonics into a scientifically rigorous and professionally accountable discipline.

The End

References

37) Darwin, M. A new kind of CPR. CryoCare Report #2 online edition, July 1994: http://www.cryocare.org/index.cgi?subdir=&url=ccrpt2.html#GUIDELINES. Retrieved 2011-01-24.

38) Darwin, M. Cryopreservation of James Gallagher, CryoCare patient #C-2150: http://www.alcor.org/Library/html/casereportC2150.htm.  Retrieved 2011-01-29.

39)  Darwin, M. Cryopreservation case report: Jerome Butler White, http://cryoeuro.eu:8080/pages/viewpageattachments.action?pageId=425990&sortBy=date&highlight=White_Jerome_Butler_Case_Report.pdf&. Retrieved 2011-01-30.

40)  Darwin, M. Cryopreservation case report: Richard Putnam Marsh, ACS 5694.  http://cryoeuro.eu:8080/pages/viewpageattachments.action?pageId=425990&sortBy=date&highlight=Marsh%2C+Richard+P.+Cryopreservation+Summary.pdf&. Retrieved 2011-01-30.

41) Darwin, M. Cryopreservation of James Gallagher, CryoCare patient #C-2150: http://www.alcor.org/Library/html/casereportC2150.htm.  Retrieved 2011-01-29.

42) Darwin, M. Cryopreservation case report: Jerome Butler White, http://cryoeuro.eu:8080/pages/viewpageattachments.action?pageId=425990&sortBy=date&highlight=White_Jerome_Butler_Case_Report.pdf&. Retrieved 2011-01-30.


[1] Extracorporeal Membrane Oxygenation (ECMO).

[2] Cardiopulmonary bypass (CPB).

[3] Of course, one problem with this charge is that our patients are legally dead. It is only possible to practice medicine on legally dead people under special circumstances, such as performing a medico-legal autopsy.

[4] Emergency Medical Technician (EMT)

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A Brief Pictorial History of Extracorporeal Technology in Cryonics – Part 4 http://chronopause.com/index.php/2011/02/07/a-brief-pictorial-history-of-extracorporeal-technology-in-cryonics-%e2%80%93-part-4/ http://chronopause.com/index.php/2011/02/07/a-brief-pictorial-history-of-extracorporeal-technology-in-cryonics-%e2%80%93-part-4/#comments Mon, 07 Feb 2011 20:19:23 +0000 admin http://chronopause.com/?p=47 Continue reading ]]> By Mike Darwin

Reaching for Extracorporeal Excellence

Figure 27: Tamari-Kaplitt Pulsator being used for cryoprotective perfusion of a patient on 12 December, 1988.

From the time Jerry and I took charge of patient care at Alcor, both standard and cutting edge extracorporeal medical technology was applied to cryonics patients with both a high degree of competence and success.[1] That does not mean that we had the latest equipment, or the most elegant surroundings, because we usually did not. Nor do perfusionists or intensivists in New Zealand, or in the UK today, and yet despite (or perhaps because of) a relative paucity of the very latest devices in their ICUs and ORs, their patient outcomes, in terms of both morbidity and mortality, are better, on average, than those in the US – and these outcomes are achieved at markedly lower costs.22,23 Years before US intensivists abandoned the routine use of pulmonary artery catheters (Swan-Ganz catheters), their use had been discontinued completely in New Zealand’s ICUs: there is no substitute for good clinical judgment and the intelligent use of technological resources.

After validating that pulsatile flow was significantly better at facilitating cryoprotective equilibration and controlling cerebral edema in ischemic cryopatients (using an animal model employing the radioactive microsphere technique for determining regional flows), we acquired a Tamari-Kaplitt Pulsatile (TKP) flow device, 24 which was used until the manufacturer, Shiley, ceased making the disposable component of the system. The TKP produced truly effective pulsatile flow, and was ideal for use in cryonics operations, because it could be used with hollow fiber oxygenators and, when used under the asanguineous, low-flow, low and slow pulsatility conditions necessary for CPA perfusion, the TKP did not present the risk of cavitation of the perfusate (and accompanying gas embolus formation) or hemolysis that it did in normal clinical use.25

Figure 28: Disposable pulsator chamber of the Tamari-Kaplitt Pulsator (foreground). A chamber comprised of a flexible membranous section of the arterial line, contained within a hard outer shell, generated pulsatile flow using compressed gas. Shiley discontinued manufacturing this component rendering the device obsolete and unusable.

While inferior to the TKP in generating pulsatile flow, we acquired a Sarns DX Pulsatile Pump early in 1990 at the then (to us) staggering cost of $4,500.

Figure 29: Sarns DX pump (left side of the heart-lung machine console) being used with a Kolobow silastic membrane oxygenator to provide pulsatile flow for a patient on 31 December, 1990. An added expense that accompanied the loss of the TKP was the need to use Kolobow ‘true membrane’ oxygenators in order to minimize damping of the pulse wave that occurs with hollow fiber oxygenators. The TKP pulsation generator bypassed the oxygenator and was positioned in-line, adjacent to the arterial cannula.

However, all the extracorporeal acumen in the world cannot make up for prolonged exposure to normothermic ischemia, and here too Alcor was a leader, both in applying existing technology for cardiopulmonary support (CPS), and in extending it to well beyond what clinical medicine had to offer at that time. By November of 1985 we had deployed emergency response kits equipped with a mechanical heart-lung resuscitator (HLR), 1st generation cerebroprotective drugs, cooling equipment (Portable Ice Baths, PIBs) and temperature monitoring equipment to the US, Canada and the UK.26 Also included were small compressed oxygen cylinders as well as oxygen regulators to interface with high capacity H-cylinders to allow for extended HLR run times.

What’s more, we had also acted aggressively to equip the South Florida Alcor group with full capability for Standby, Transport, and cryoprotective perfusion. We also established periodic training sessions using a survival animal model as well as didactic and hands-on training sessions held more frequently to establish and maintain emergency response and Transport skills. 27

Figure 30: At top, Mike Darwin, with the 1st generation of emergency response kits just prior to their deployment in 1985; and at bottom, the map of the US showing the location of emergency kits and of all Alcor members as of May, 1986.

Figure 31: Operating room in the Alcor South Florida facility in May of 1987; invasive pressure monitoring equipment on cart at left, hot suction on white cart at center, defibrillator & monitor on stainless steel back table at upper left, electrocautery on cart in foreground, and operating table lower left.

These training sessions were held on-site to facilitate participation by the maximum number of local members possible, and additional training was conducted at Alcor’s facilities in Fullerton, and later in Riverside, CA.

Figure 32: Extracorporeal supplies cabinets in the Alcor Florida facility in May of 1987.

Figure 33: Alcor member Gil Ross looks on as preparations are underway for a training session. In the foreground is the American Optical heart-lung machine which was to be used for cryoprotective perfusion in the South Florida facility.

Only someone who was willfully ignorant or malicious could look at these photos and read the published accounts of the time (which are readily accessible on-line) and claim that cryonics, at least as practiced by Jerry Leaf and I, was in any way divorced from extracorporeal medicine and technology. What is seen, and seen consistently, is the use of conventional medical technology, and in particular conventional perfusion technology, to such an extent that it would be difficult to differentiate any of these facilities as being cryonics operations, as opposed to CPB surgical suites in experimental laboratories or clinical environments around the world at that time.

Training sessions in basic emergency response were frequent, lasted several days, and were achievement validated; individuals either mastered the skills sets required and passed the exams, or they were not certified as Level 1 Transport Techs.

Figure 34: Saul Kent practicing set-up of the Michigan Instruments 1008 heart-lung resuscitator during a training session conducted in South Florida, circa 1987.

And no one was exempt from DIY cryonics. There was very little money in those days and the people who wanted cryonics for themselves had no choice but to learn to do it for themselves. Equipment was purchased used, often for pennies on the dollar, and with the exception of myself and Hugh Hixon, no one was paid in any way for their services (and Hugh and I were paid precious little).

Figure 35: Left to right: Thomas Donaldson, Cath Woof and Linda Chamberlain practicing applying and operating the Brunswick HLR-50-90 at an Alcor Transport training session hosted by the Donaldson’s at their home in Sunnyvale, California.28

It is egregiously malicious, as has been done recently, to ridicule some of the very people who were down on their hands and knees in these photos learning to do for themselves, as best they could, what virtually no medical professionals at that time were willing to teach – let alone to do. Even had we had the money (which we did not), it was impossible to find professionals with both the skills and the time to do the jobs we were forced to do ourselves – though let the record note that we certainly tried mightily to recruit such people, and in a few cases succeeded. But it was never enough to equal the task at hand. The need to earn a livelihood, as well as geographical distance, proved formidable barriers.

Figure 36: Mike Darwin and Thomas Donaldson preparing to practice endotracheal intubation skills at an Alcor Transport training session hosted by the Donaldson’s at their home in Sunnyvale, California.

As early as February of 1985 we began the practice of in-field blood washout of cryopatients (TBW) at local mortuaries and this practice was routinely implemented for every Alcor patient who could benefit from it.[[2]] 29-32 Why was this done in mortuaries as opposed to in the hospitals where the patients were pronounced? The answer is that there was no medical facility who would even consider allowing such care to proceed in their facilities – which was a moot point anyway, since no physician or technician on their staff was interested in assisting with, let alone undertaking such a task on their own initiative. One of my most vivid memories of a patient Transport was when a staff physician at the hospital where I was undertaking to Transport the patient – literally connecting the patient to the HLR and intubating him – walked into the ICU cubicle and began to rail at me about what the patient’s future employment prospects would be, and who would pay to reeducate him if he was revived![3] The majority of physicians then, as is the case with those who now attack cryonics, while loudly professing their desire to save it, not only don’t want to help cryonicists – they want to destroy cryonics.

After years of scrounging, scrimping and saving, Jerry Leaf and Hugh Hixon completed construction of a mobile ‘extracorporeal membrane oxygenation’ (ECMO) cart.33 This device was fabricated in-house, not just because we had virtually no money, but because there was no commercial manufacturer for such a piece of equipment when the project was begun in 1982 – and indeed there was no commercial manufacturer after it was completed in 1986, either. In fact, 25 years later, there are still no commercially produced integrated adult ECMO carts! The cart was first applied to a young man, who unexpectedly arrested from sepsis secondary to HIV, on 08 June, 1987.34

Figure 37: Patient undergoing mechanical CPS as a bridge to ECMO support in the Alcor ambulance in June of 1987. Left to right above are: Mike Darwin, CRT, Carlos Mondragon and Scott Greene, RN.

The patient was transported from the hospital where he arrested to Alcor’s facilities in Riverside, CA using closed chest mechanical CPS as a bridge to ECMO. The three photos below illustrate the extracorporeal circuit and the configuration of the 1st generation cryonics ECMO cart, which was christened the Mobile Advanced Life Support System (MALSS).

Figure 38: Jerry Leaf preparing to install aneroid ‘back pressure ‘ monitoring gauge on the arterial filter of the bypass circuit.

Figure 39: Jerry Leaf, preparing to secure the arterial and venous lines to the lower structural support rail of the MALSS, while Scott Greene, RN, suctions the patient.

Figure 40: The patient on CPB undergoing cooling to 15oC prior to blood washout and cryoprotective perfusion.

Where use of the MALSS was not feasible due to distance or logistics, in-field CPB with blood washout continued to be used, as is illustrated in Figure 41.

Figure 41: Jerry Leaf prepares the in-field CPB circuit for connection to Dr. Eugene Donovan, M.D., who was cryopreserved by Alcor on 21 March, 1989. The patient is receiving continuous cardiopulmonary support via a pneumatically powered chest compressor and ventilator.

After Jerry was cryopreserved in July of 1991, Alcor continued to offer extracorporeal and cryonics care that was of extraordinarily high quality. As a result of in-house research on developing improved methods of CPS, Alcor began the use of high impulse CPR (HI-CPR); a modality that has only within the past year become the standard of care in the US. I worked closely with Michigan Instruments, spending a week in Grand Rapids, to develop of a heart-lung resuscitator capable of delivering HI-CPR.35

Figure 42: Patient undergoing high impulse CPS as a bridge to CPB cooling and blood washout on 12 December, 1991.

On 12 December, 1991 Alcor placed the first human cryopatient on CPB in his home. HI-CPR, starting within 2 minutes of pronouncement, served as a bridge to CPB which was initiated within~100 minutes of cardiac arrest.36

Figure 43: CPB supported induction of ultraprofound hypothermia being undertaken in the living room of a cryopatient’s home for the first time, on 12 December, 1991.

Figure 44: Femoral cannulae, arterial and venous lines, pressure monitoring line and aneroid, 12 December, 1991.

End of Part 4

References

24) Kaplitt MJ, Tamari Y, Frantz SL, et al. Clinical experience with Tamari-Kaplitt pulsator. NY State J Med. 1978;78:1090.

25)  Wise EA, Mandl JP, Zaayer WE. Gaseous emboli generation by a pulsatile assist device. J Extracorp Tech. 1978;10:93.

26) Editorial Staff. ALCOR Coordinators:  Training and Equipment Deployment. Cryonics. 7(1);1986:2-4. http://www.alcor.org/cryonics/cryonics8601.txt. Retrieved 2011-01-24.

27) Editorial Staff, CSSF merges with Alcor. Cryonics. 6(1);1985:2-6: http://www.alcor.org/cryonics/cryonics8501.txt. Retrieved 2011-01-24.

28)  Adventure in Sunnyvale. Cryonics. 7(9);1986:5-8: http://www.alcor.org/cryonics/cryonics8609.txt.  Retrieved 2011-01-24

29) Darwin, MG, Leaf, JD, Hixon, H. Case report: neuropreservation of Alcor patient A-1068. 1 of 2, Cryonics. 7(2);17-32:1986: http://www.alcor.org/cryonics/cryonics8504.txt. Retrieved 2010-08-31. Retrieved 2011-02-25.

30)  Darwin, M, Bridge S. The cryonic suspension of A-1242. Cryonics 11(10)1990:18-22. 2010-09-29. http://www.alcor.org/cryonics/cryonics9010.txt. Retrieved  2010-09-29. Donovan, C and Donovan, J. A dream in his pocket: the cryonic suspension of Eugene T. Donovan. Cryonics. 11(2);29-45:1990:   http://www.alcor.org/Library/html/casereport9002.html.  Retrieved 2011-01-28.

31)  Darwin, MG, Cryopreservation case report: Arlene Francis Fried, A-1049: http://www.alcor.org/Library/html/fried.html. Retrieved 2011-01-30.

32)  Henson, K, Darwin, M. The Transport of Patient A-1312S. http://www.alcor.org/Library/html/casereport9202.html. Retrieved 2010-08-31.

33)  Leaf, J, Hixon, H, Darwin, M. Development of a mobile advanced life support system for human biostasis operations. Cryonics. 1987; 8(3):23-40: http://www.alcor.org/cryonics/cryonics8703.txt.  Retrieved 2011-01-24.

34) Darwin, M. Cryonic suspension case report A-1133. http://www.alcor.org/Library/pdfs/AlcorCaseA1133.pdf.  Retrieved 2011-01-24.

35)  Darwin, M. A major advance in suspension patient support. Cryonics. 10(8):1989:7-14.  http://www.alcor.org/cryonics/cryonics8908.txt. Retrieved   Retrieved 2011-01-24.

36)  Henson, K, Darwin, M. The Transport of Patient A-1312S. http://www.alcor.org/Library/html/casereport9202.html. Retrieved 2010-08-31.


[1] Success being defined here is effective cryoprotective loading, absence of iatrogenic events and in those cases where it was possible, preservation of viability until cryoprotective perfusion was undertaken.

[2] Some patients were not candidates for this treatment as a result of being Coroner/Medical Examiner cases, or experiencing unanticipated and distant cardiac arrest.

[3] My retort was that the good Doctor shouldn’t worry about having to pay for those things, because unless he was cryopreserved himself, he would be long dead and buried before the patient was reanimated.

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A Brief Pictorial History of Extracorporeal Technology in Cryonics – Part 3 http://chronopause.com/index.php/2011/02/06/a-brief-pictorial-history-of-extracorporeal-technology-in-cryonics-%e2%80%93-part-3/ http://chronopause.com/index.php/2011/02/06/a-brief-pictorial-history-of-extracorporeal-technology-in-cryonics-%e2%80%93-part-3/#comments Mon, 07 Feb 2011 06:55:40 +0000 admin http://chronopause.com/?p=41 Continue reading ]]> By Mike Darwin

A Great Team

In January of 1980 I stabilized and transported a patient from southern Wisconsin for TT to Cryovita Labs. Jerry kindly invited me to stay and participate in this patient’s cryoprotective perfusion (CPA) perfusion and cool down and I readily accepted.

Figure 15: Jerry Leaf at left and Mike Darwin at right performing the initial examination of a patient stabilized remotely in Wisconsin and Transported to the facilities of Cryovita Laboratories in 1980.

Figure 16: Patient undergoing median sternotomy prior to cannulation for cryoprotective perfusion at Cryovita Laboratories in 1980.

Figure 17: Intravascular pressure monitoring set-up (Intraflow™, stopcock manifold, Statham pressure transducer and calibrating mercury manometer) as used to monitor cryopatient arterial and central venous pressure at Cryovita Laboratories in 1980.

Figure 18: Heart-lung machine and extracorporeal circuit employed to carry out cryoprotective perfusion of cryopatients at Cryovita Laboratories in 1980.

As we were finishing up this case, another patient, a long-time member of the Bay Area Cryonics Society, experienced unexpected cardiac arrest and presented for cryopreservation. With almost no sleep, and virtually no turnaround time between cases, this patient was cryopreserved, as well. A detailed technical report on both of these cases was published in Cryonics magazine in 1985.12

Doing those two cases with Jerry convinced me that that the most effective and important action I could take to both further cryonics (and improve my own skills) was to shutter the now considerable cryonics operations in Indianapolis, and relocate to work with Jerry in Southern California. That is exactly what I did in the spring of 1981. My reasons for this are best articulated by Jerry in an interview he gave in August of 1986:

“In 1980 I had the occasion to make personal contact with Mike Federowicz, who I had corresponded with before. Mike had transported a Trans Time patient to Southern California and then stayed on to help with a second suspension which came on the heels of the first. Mike had been working in a cryonics group in Indianapolis, Indiana for a number of years. At that time I tried to open the door as far as doing what I could to persuade him that Southern California offered an attractive alternative to the difficulties he was experiencing in Indiana. I needed someone else out here to work with who had a background in clinical medicine, such as Mike did, and he himself had begun to move toward clinical models of perfusion — using roller pumps and so on. I felt that he and I working together would allow us both to accomplish a lot more than if we were working alone. He was the only one else in the world who seemed to be aware of the fact that something needed to be done to upgrade the level of care — and to realize that that meant medical technology.”13

Throughout the early and mid-1980s – often under very trying conditions, and with virtually no money other than that which we earned ourselves, Jerry, I and the small band of committed cryonicists that comprised Alcor at that time, relentlessly accumulated equipment and conducted basic research to determine just how effective (or ineffective) then current cryopreservation techniques were at preserving both viability and structure. We also began the very successful canine total body washout (TBW or blood washout) and extended ultraprofound hypothermic asanguineous perfusion research work which culminated in consistent recovery of the animals from 4 hours of perfusion at ~5oC.14 Our thanks for that was not infrequent harsh criticism, most of which emanated from our fellow cryonicists.15,16

Figure 19: Shiley pediatric blood oxygenator (bubbler) and blood reservoir bags used to hold the animal’s blood during asanguineous perfusion at Cryovita Laboratories on 17 March, 1984. The stainless steel basin was used to collect discard effluent at the tail end of blood washout and replacement.

Over the past two years, this work has been has been decried as useless, scientifically invalid, and it has been implied it was conducted in an unlicensed facility, using illegally obtained animals.  In fact, Cryovita was a USDA[1] licensed facility from well before the time that any animal (other than the human kind) entered the premises. Jerry was inordinately proud of his USDA license, and Cryovita was inspected frequently by the USDA, and never had a serious violation. At the time this research began in the late 1970s and early 1980s, ‘pound seizure’ was an operational and fully legal mechanism for acquiring dogs and cats for research.

While still technically legal in many states, including California,17 pound seizure has effectively been all but abolished, and the result is that each year, according to the US Humane Society, 6-8 million dogs and cats are killed; to no purpose but to dispose of them. I have personally witnessed this process at a variety of facilities and most of the animals die in terror and confusion – many having been injured by others of their species while ‘timing-out’ in local government custody. Their deaths serve no purpose but to dispose of a suffering and ‘unwanted’ commodity produced by irresponsible and cruel people.  The majority of animal research facilities at the time when pound seizure was operational provided exemplary and kind care for the animals they used for experimental purposes. In fact, such care is essential to good research, because a stressed, malnourished and unconditioned animal will yield suspect or meaningless experimental results.

Thus, experimental animals obtained from the pound, or from licensed dealers or breeders must be wormed, vaccinated, well fed and emotionally supported prior to use in experimental procedures. Just as much to the point, the vast majority (>90%) of such procedures employing dogs and cats are ‘acute procedures.’ That means that the animal is placed in deep anesthesia and never awakens from the procedure. In practice, this means additional weeks of life for the animal under humane conditions, and a death that is virtually identical to that it would have experienced if ‘euthanized’ in the pound.

Chronic studies are carefully regulated, and an animal can be used only once for any such study, and indeed, for any experimental procedure.18 A consequence of the Animal Rights Activists’ intervention to prevent pound seizure has been the useless and irresponsible deaths of millions of discarded animals. And keep in mind that one of the biggest beneficiaries of animal research are arguably the animals themselves – since many procedures targeted for human use cannot jump the FDA regulatory or marketing hurdle for human application – but can do so for animals. Joint replacement, NF-kappa B non-steroidal chronic pain drugs such as Rimadyl (carprofen),19 and most recently, joint regeneration (using fat derived stem cells) in dogs20 with degenerative hip disease are but a few examples of treatments developed via animal experimentation that now benefit countless companion animals around the world.

Research Drives Excellence

As to the utility of the canine TBW work, we were the first to demonstrate that intracellular solutions of the kind used for organ preservation were useful for prolonged asanguineous perfusion, the first to demonstrate that extended (4 hour) asanguineous perfusion was routinely survivable in dogs with normal mentation, and the first to demonstrate the conservation of mammalian memory and personality after cooling to ~5oC. The Society for Cryobiology refused to publish our paper, and they worked relentlessly to ensure that no other journal would publish a paper from ‘body freezers.’ This work is available on line, and it is now possible for people to judge for themselves. This work by Cryovita and Alcor, which was carried out in the early 1980s, was not repeated until 1991 with the publication of nearly identical work by Bailes, et al. Interestingly, one of the investigators on that paper (who later became the principal person conducting subsequent work in this area), was Michael Taylor, Ph.D., of the Society for Cryobiology, who also happened to be one of the reviewers who rejected the Cryovita-Alcor TBW study in the 1980s.20,21

As was the case in most animal research labs then, much of our equipment was ‘older but serviceable.’ Indeed, UCLA sometimes had equipment that was no better, and was not infrequently more time worn.

Figure 20: Mike Darwin preparing an ‘ancient’ Travenol RSP dialysis machine for electrolyte normalization and hemoconcentration on the TBW dog ‘Enkidu’[2] on 17 March, 1984 at Cryovita Laboratories.

Paradoxically, sometimes the latest equipment is an absolute barrier to its use in a research application by virtue of its technological sophistication. I used hemodialysis with ultrafiltration to normalize blood electrolytes in the animals after blood replacement and to extract water from the extracorporeal circuit and vascular space – the latter to raise both the oncotic pressure and the hematocrit – this was before the advent of microporous hollow fiber hemoconcentrators in CPB. Because the intracellular perfusate we used (MHP-2[3]) contained 40 mEq/L of potassium, and very little sodium, even after the blood was replaced, the animals had cardioplegic levels of potassium present in their blood. It was most efficient to normalize the blood potassium level via dialysis – but this required that the dialysate be customized to our application.

Figure 21: Continuous monitoring of dialysate pH during rewarming with dynamic adjustment of pH being carried out by the addition of sodium hydroxide solution to the dialysate via the top ‘mixing compartment’ of the RSP dialysis machine. The bottle of Hemastix was used to check the dialysate returning from the dialyzer for hollow fiber breaks that could result in blood leaks from extracorporeal circuit into the dialysate.

Unfortunately, all of the then state-of-the-art equipment, such as the Cobe Sentry II dialysis machine,  used ‘proportioning technology’ to mix the dialysate in real time; and these machines also had built in conductivity monitors that would shut the system down in the event the electrolyte concentration was sensed to be inadequate. It was also impossible to dynamically adjust the pH of the dialysate in a proportioning system. The very technological safeguards and ‘undefeatable’ automation built into the system to make it safe and more ‘foolproof’ also rendered it useless for research! As a consequence, I had to locate batch-type machines from the late 1960s, and single pass convertors from the 1980s, to allow for the use of hollow fiber dialyzers in order to use this modality on our animals. Newer isn’t always better.

Figure 22: Bilateral femoral cannulation was used for the TBW experiments. In this photograph the arterial, venous, dialysis and pressure monitoring lines are visible during the perfusion of TBW dog ‘Enkidu’ on 17 March, 1984 at Cryovita Laboratories.

Figure 23: One unexpected consequence of using hyperosmolar extracellular solution for asanguineous perfusion was the extraction of non-vascular water from the aqueous and vitreous humors or the eyes (as well as the cerebrospinal fluid). As can be seen in this photo (TBW dog ‘Enkidu’ on 17 March, 1984 at Cryovita Laboratories), the eyes become sunken and flaccid during perfusion and this raised concern that retinal detachment might occur. This did not happen, and despite large reductions in brain volume and ‘ocular flattening,’ the animals recovered normally and lead normal, healthy lives, dying of old age in their mid-teens.

Figure 24: The Awakening: This candid photo perfectly captures the sense of wonder and anticipation that everyone who was involved in these experiments experienced at the time. When this photo was taken, Enkidu had just begun to recover a ‘lash reflex,’ indicating the imminent return of consciousness. From left to right: Mike Darwin, Garret Smyth, Max More and Brenda Peters.

Figure 25: Mike Darwin giving ‘assist’ ventilations to a dog recovering from 4 hours of asanguineous perfusion at Cryovita Laboratories in 1981.

Figure 26: Alcor member and volunteer Anna Tyeb restrains a rambunctious ‘Enkidu’ a few days after he underwent 4 hours of asanguineous perfusion at ~5oC.

There are literally hundreds of photographs of these experiments, as well as half a dozen videotapes; most of which have not yet been digitized. They document virtually every facet of the extracorporeal technology used to carry out this research. I do not merely believe, I know (from experience) that the equipment and techniques we employed were exemplary and representative of the standard of care in both experimental cardiopulmonary bypass laboratories, as well as many of the clinics of the day. Alcor cryonicists have a great deal to be proud of in terms of both advances in research, and clinical (cryopatient) care, during this period and throughout the 1980s (certainly up until the departure of Jerry Leaf and me from Alcor in 1991).

Why was this research done? For many reasons, not the least of which was that we hoped that by applying the same technology of intracellular perfusates that had allowed for 12 to 24 hour clinical cold storage of organs for transplant (such as the kidney and liver) to whole animals, we might possibly enable the creation of emergency ultraprofound ‘preservative hypothermia’ as a viable clinical modality. This technology would allow for rapid, in-field, or in-hospital asanguineous perfusion and cooling to a few degrees above 0oC; thus enabling victims of both civilian and battlefield exsanguinating trauma to enter a state of temporary ‘suspended animation,’ buying them time to reach sophisticated medical facilities where definitive treatment would be available. Twenty years later, this idea is now being seriously explored by some of the most outstanding research and clinical institutions in the US. Note the dates of publication on these papers – they come nearly two decades after we first successfully recovered dogs from four hours of asanguineous ultraprofound hypothermia:

1: Bellamy R, Safar P, Tisherman SA, Basford R, Bruttig SP, Capone A, Dubick MA, Ernster L, Hattler BG Jr, Hochachka P, Klain M, Kochanek PM, Kofke WA, Lancaster JR, McGowan FX Jr, Oeltgen PR, Severinghaus JW, Taylor MJ, Zar H. Suspended animation for delayed resuscitation. Crit Care Med. 1996 Feb;24(2 Suppl):S24-47. Review. PubMed PMID: 8608704.

2: Safar P, Tisherman SA, Behringer W, Capone A, Prueckner S, Radovsky A, Stezoski WS, Woods RJ. Suspended animation for delayed resuscitation from prolonged cardiac arrest that is unresuscitable by standard cardiopulmonary-cerebral resuscitation. Crit Care Med. 2000 Nov;28(11 Suppl):N214-8. Review. PubMed PMID: 11098950.

3: Tisherman SA. Suspended animation for resuscitation from exsanguinating hemorrhage. Crit Care Med. 2004 Feb;32(2 Suppl):S46-50. Review. PubMed PMID: 15043228.

4: Safar P, Behringer W, Böttiger BW, Sterz F. Cerebral resuscitation potentials for cardiac arrest. Crit Care Med. 2002 Apr;30(4 Suppl):S140-4. Review. PubMed/ PMID: 11940789.

5: Tisherman SA, Rodriguez A, Safar P. Therapeutic hypothermia in traumatology. Surg Clin North Am. 1999 Dec;79(6):1269-89. Review. PubMed PMID: 10625978

6: Marion DW, Leonov Y, Ginsberg M, Katz LM, Kochanek PM, Lechleuthner A, NemotoEM, Obrist W, Safar P, Sterz F, Tisherman SA, White RJ, Xiao F, Zar H.Resuscitative hypothermia. Crit Care Med. 1996 Feb;24(2 Suppl):S81-9. Review. PubMed PMID: 8608709.

7: Shoemaker WC, Peitzman AB, Bellamy R, Bellomo R, Bruttig SP, Capone A, DubickM, Kramer GC, McKenzie JE, Pepe PE, Safar P, Schlichtig R, Severinghaus JW, Tisherman SA, Wiklund L. Resuscitation from severe hemorrhage. Crit Care Med.1996 Feb;24(2 Suppl):S12-23. Review. PubMed PMID: 8608703.

8: Alam HB, Koustova E, Rhee P. Combat casualty care research: from bench to the battlefield. World J Surg. 2005;29 Suppl 1:S7-11. Review. PubMed PMID: 15815839.

9: Fukudome EY, Alam HB. Hypothermia in multisystem trauma. Crit Care Med. 2009 Jul;37(7 Suppl):S265-72. Review. PubMed PMID: 19535957.

10: Janata A, Weihs W, Schratter A, Bayegan K, Holzer M, Frossard M, Sipos W, Springler G, Schmidt P, Sterz F, Losert UM, Laggner AN, Kochanek PM, Behringer W. Cold aortic flush and chest compressions enable good neurologic outcome after 15 mins of ventricular fibrillation in cardiac arrest in pigs. Crit Care Med. 2010;38(8):1637-43. PubMed PMID: 20543671.

End of Part 3

References

12) Leaf, JD. Federowicz, M. Hixon, H. Case report: two consecutive suspensions, a comparative study in experimental human suspended animation. Cryonics.  6(11):13-38;1985:  http://www.alcor.org/Library/html/casereport8511.html. Retrieved 2010-08-31.

13) Darwin, M, Interview with Jerry Leaf, Part I. Cryonics. 7(7);26-34:1986. http://www.alcor.org/Library/html/Interview-JerryLeaf.html. Retrieved 2011-01-24.

14)  Leaf, JD, Darwin, M, Hixon, H. A mannitol-based perfusate for reversible 5-hour asanguineous ultraprofound hypothermia in canines: http://www.alcor.org/Library/html/tbwcanine.html. Retrieved 2011-02-24.

15) Darwin, M. The myth of the golden scalpel. Cryonics. 7(1);15-18:1986: http://www.alcor.org/Library/html/MythOfTheGoldenScalpel.html.  Retrieved 2011-01-24.

16) Darwin, M, Interview with Jerry Leaf, Part I. Cryonics. 7(7);26-34:1986. http://www.alcor.org/Library/html/Interview-JerryLeaf.html. Retrieved 2011-01-24.

17)  http://www.banpoundseizure.org/yourstate.shtml. Retrieved 2011-01-24.

18)  PUBLIC LAW 101-624–NOV. 28, Protection of Pets. 1990http://awic.nal.usda.gov/nal_display/index.php?info_center=3%20&tax_level=4&tax_subject=182&topic_id=1118&level3_id=6735&level4_id=11096&level5_id=0&placement_default=0. Retrieved 2011-01-25.

19) Committee for the Evaluation of Veterinary Products, European Agency for the Evaluation of Medicinal Products, EMEA/MRL/042/95/FINAL. http://www.ema.europa.eu/docs/en_GB/document_library/Maximum_Residue_Limits_-_Report/2009/11/WC500011412.pdf.  Retrieved 2011-01-25.

20)  http://www.vet-stem.com/smallanimal/. Retrieved 2011-01-24.

21)  Bailes JE, Leavitt ML, Teeple E, Maroon JC, Shih SR, Marquart M, Elrifai AM, Manack L. Ultraprofound hypothermia with complete blood substitution in a canine model. J Neurosurg. 1991;74:781-788.

22)  Elrifai AM, Bailes JE, Leavitt ML, Teeple E, Shih SR, Taylor MJ, Maroon JC, Ciongoli KA, Devenyi C, Rosenberg I. Blood substitution: an experimental study. J Extracorp Tech. 1992;24:58-63.


[1] The United States Department of Agriculture is the regulatory agency that oversees animal research facilities in the US.

[2] The name for this dog was chosen by Alcor activist and research volunteer Anna Tyeb. Enkidu was a character in the Sumerian Epic of Gilgamesh, the oldest known human book, recorded on 12 clay tablets dated to ~3000 BCE. Enkidu is a wild-man who symbolizes the untamed natural world, and though he is the cultured Gilgamesh’s equal in strength and courage, he is in many ways his antithesis. After a wrestling match between the two, Enkidu becomes a friend and soul mate, and Gilgamesh’s constant companion in adventure; until he is taken ill and dies. The death of Enkidu wounds and enrages Gilgamesh, forcing him to realize that he had “loved and lost a friend to death, and learned he lacked the power to bring him back to life.” This inspires Gilgamesh on a quest to escape death by obtaining physical immortality.

[3] MHP is Mannitol-HEPES perfusate; mannitol is the impermeant sugar-alcohol and the zwitterionic buffer sodium HEPES was the primary buffer.

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