X-Message-Number: 3375
From: Brian Wowk <>
Date: Wed, 2 Nov 94 12:29:12 CST
Subject: SCI.CRYONICS Hyperbaric Freezing

        The subject of cooling at hyperbaric pressures to reduce or 
prevent freezing injury has been raised numerous times by various 
individuals over the history of cryonics.  While it looks good on 
paper, it would be nightmarishly complicated in practice.
 
        The extremely high pressures mentioned in the current 
discussion (14000 atmospheres) are equivalent to being some 400,000 
feet under water (more than ten times deeper than Challenger Deep in 
the Marianas trench of the Pacific).  Hydrostatic pressures of this 
magnitude would not be biologically innocuous.  A high incidence of 
neurological tremors (possibly caused by protein denaturation) are a 
limiting factor for commercial divers at only 2000 feet.
 
        It is also highly likely that the engineering expertise for 
building macroscopic chambers to sustain 14,000 atmospheres does not 
exist anywhere in the world.  This is a project that would cost 
millions (if not tens of millions) of dollars to implement.  It is two 
to three orders of magnitude beyond the research budgets of cryonics 
organizations today.
 
        But the REAL point is this: We may already have technology for 
completely preventing freezing injury.  Greg Fahy has successfully 
vitrified (cooled without freezing) whole kidneys at -130'C, and 
rapidly rewarmed small slices.  The rewarmed slices show perfect 
viability.  (The trick is to rewarm extremely fast so that the tissue 
doesn't devitrify (freeze) during warming.  Hence the small slices.)  
If means existed for rapidly rewarming the entire organ, it is very 
likely that we could demontrate perfected organ cryopreservation RIGHT 
NOW.  The problem is (wait for it!)-- THE >>>FDA<<<!  The high power 
rf heating appartus that Greg Fahy paid to have developed by an FDA 
researcher is now caught up in FDA red tape, and has been for the past 
year.  Essentially the possible answer to all our brain preservation 
problems in cryonics is a piece of paper sitting on David Kessler's 
desk, waiting to be signed.
 
--- Brian Wowk  

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