Heart Beat: Chilling out
If the thought of having a heart attack or cardiac arrest sends a chill down your spine, having one could lead to chills all over. An approved but little-used technique known as therapeutic hypothermia "" rapid cooling of the body "" improves survival and limits brain damage from cardiac arrest, the sudden cessation of an effective heartbeat.
Cooling slows chemical reactions and cell metabolism. This reduces a tissue's need for oxygen. Think of it as artificially induced hibernation. Surgeons have long used this trick to protect the heart, brain, and other organs during open-heart surgery. A handful of medical centers have used rapid cooling for people resuscitated after a cardiac arrest. Researchers are testing its benefits, and risks, during emergency artery-opening angioplasty to halt a heart attack. It is also being eyed as a way to protect the brain during and after a stroke.
Still, doctors and emergency responders haven't been quick to use hypothermia. Some remain skeptical; some await the results of ongoing trials; others aren't sure of the safest and most effective way to quickly cool the body.