Charles Platt - writer. Wrote an article "Heart and Cool Oxygen", which describes this technique. You can view some photos of the device that Charles built, as well.
critical care research, inc.
research director - steven harris
Bad news - 300,000 cases of cardiac arrest in the US. Without blood flowing, body goes south pretty quick. Cells lose fluid balance - don't have energy to operate, cells shutdown / swell up, blood vessels squeeze up.
Cells start to poison themselves, and then eventually destroy themselves. Can try to use drugs - but it is a cascade of bad things happening, so you need to take a combination of drugs, which is a combinatorial treatment (multi drug interactions), FDA doesn't like.
CPR doesn't get enough blood to flow.
Can jack up blood pressure, to try and force blood through constricting vessels.
Answer: Reduce temperature of person. Hard to take the heat out quickly - due to body mass, have to conduct heat through mass of tissue, out. We know that cooling works, because of fascinating cases of people found "dead" in snow drifts or ice-cold water. Even with no heartbeat / brain activity for over an hour, can be brought back. Especially children - higher surface area to mass ratio, easier to cool them. Have to cool fairly rapidly.
Hypothermic surgery - brain aneurism that can only be operated on w/o any blood pressure at all - will stop heart completely for upto an hour, by reducing temperature of body by 20 degrees beforehand.
Works even a little after the event.
Clever idea: Lungs have a large area within them, which is good for cooling. Need to use a liquid -- it is more effective than gas. Use perfluorocarbon, which is 1.8 times as heavy as air.
Warm blood goes by lungs, gets cooled, goes up to brain. Super-effective if you start even 15 minutes after cardiac arrest. Critical Care Research is doing tons of animal trials, and has proven this to be effective in dogs - 100% revival rate, no brain damage.
Artificial circulation - something called a thumper, but it has lots of limitations. Something new from Sweden - a band device. It has accelerometers that can tell how hard it is going, to self-adjust to the right rate.
Armpits and groin are best places to introduce cooling.
Totally immersed in ice water is a quarter efficient as liquid ventilation.
Flow the liquid in - takes about 7 seconds, and flow it out right away (10 seconds). Keep this running continuously. Patient is intibated during the procedure, so using a mixture of gas and liquid.
Posted by andyr at June 23, 2007 2:49 PMI came across this article a while ago about new thoughts on "cell death," specifically that it's the sudden reintroduction of oxygen that really kills 'em
http://www.msnbc.msn.com/id/18368186/site/newsweek/
Yeah, that can be a problem as well, and was discussed at the talk - I just didn't get it into my notes. Thanks for the link, I'll check it out.