X-Message-Number: 6952 From: (Brian Wowk) Newsgroups: sci.cryonics Subject: Re: Cooling Rate issue Date: 19 Sep 96 17:41:28 GMT Message-ID: <> References: <> <> In <> Terry Lambert <> writes: >This raises a number of other, related issues, then, which are >implied by the lower rate. Foremost might be the issue of how >efficient is the Visser CPA as an oxygen transport. Don't worry about it. Cells don't have much use for oxygen below 0'C. CPA is not introduced at higher temperatures because of toxicity. The technology for getting from 38'C to 0'C with minimum injury is a separate specialty that is CPA-independent. >I'm there are a large number of worms in the slow-cooling can. The biggest is going to be toxicity. We don't know what this agent will do to organs exposed to it for hours at high sub-zero temperatures. Not so much an issue for hearts, but it certainly will be for brains. >On the plus side, I'll note that gross function was restored >post thawing in the reported experiments. The thawing, without >RF heating or similar fast-thaw techniques, seems to me to be >supporting evidence. The most encouraging aspect of the slow thawing success is that it shows the heart will survive exposure to high (eutectic) concentrations of the agent for many minutes. Whether this survival time will be sufficient for cooling and thawing (with RF if necessary) of large hearts remains to be seen. The experiments must be done; done at realistic cooling rates, and on each organ individually. *************************************************************************** Brian Wowk CryoCare Foundation 1-800-TOP-CARE President Human Cryopreservation Services http://www.cryocare.org/cryocare/ Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=6952