X-Message-Number: 8314
From:  ()
Newsgroups: sci.cryonics
Subject: Re: review of suspended animation prospects
Date: 9 Jun 97 21:30:37 GMT
Message-ID: <>
References: <>


In <>  (Joseph 
J. Strout) writes:

>Suspensions of up to an hour are fairly routine (from the article, which I
>have now read), and their goal is to extend this to three hours or so.  And
>of course this is no substitute for cryonics, but that wasn't my purpose in
>pointing it out.  Rather, we should take careful note of the procedures
>used to get patients successfully down to deep hypothermia (around 5 C),
>and hold them there stably.  The very same procedures may be useful in
>cryonic suspensions to (a) get the patient's temperature down while
>preventing ischemic damage, without chemical toxicity, and (b) pause there
>as needed for evaluation, preparation, or transport, before the final
>freezing phase.

	During the mid 1980's, Jerry Leaf and Mike Darwin at Alcor set
several records for deep hypothermia recovery (which sadly were never
published in refereed journals).   Their work culminated in the
recovery of dogs after 4 hours of bloodless perfusion at 4'C.  This
record was subsequently extended at 21st Century Medicine  
to about 5 hours.  The motive of this work was exactly what you
suggest: Improving the reversibility of the early stages of human
cryopreservation. 

	It should be mentioned that there are two different models
of hypothermia: circ arrest and bloodless perfusion.  The
perfusion model allows you to get out to 5 hours near freezing, 
while circ arrest is still limited to about 2 hours.  The perfusion 
model is pertinent to what happens to cryonics patients during
stabilization and cryoprotective perfusion.  The circ arrest
model is pertinent to cryonics patients being shipped on ice 
without CPR.  


>Moreover, to the extent that we are using such procedures already (and I
>really have no idea who is and is not),  we can state with assurance that
>the cryonics patients are viable up to that point at least -- or would be,
>if not for whatever killed them in the first place.

	You can drop the "if not for whatever killed them" part.  
In the first case Biopreservation did for CryoCare (Jim Gallagher) 
there was no question that the patient was viable (and likely recoverable)
by present criteria for almost two hours after legal death.  The
blood gases and enzymes tell the tale.  It's unlikely that any
other organizations are equalling this performance since
only BioPreservation uses ACDC CPR and a constellation of new
drugs to inhibit ischemic injury.  Cryonics patients differ
from animal studies in that cryonics patients do not come
prepped with heart-lung machine support before cardiac arrest
occurs.  So how you reestablish blood circulation, cool the patient,
and medicate them are crucial to success.

 ***************************************************************************
 Brian Wowk          CryoCare Foundation               1-800-TOP-CARE
 President           Human Cryopreservation Services   
    http://www.cryocare.org/cryocare/
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