Heart Beat

Big chill for cardiac arrest

A cardiac arrest suddenly, and completely, halts blood flow to the brain. Some who survive this catastrophic event emerge relatively unscathed. Others have long-term brain damage that causes physical or mental problems. Cooling unconscious victims increases survival, limits brain damage, and provides a cost-effective treatment that is comparable to other widely used therapies, says a report in the journal Circulation: Cardiovascular Quality and Outcomes.

Rapid cooling, also known as therapeutic hypothermia, puts the body and brain into a sort of temporary hibernation. Chemical reactions and cell metabolism slow down. This reduces the damage caused by the temporary lack of oxygen that occurs when the heart stopped pumping. The researchers estimate that wider use of rapid cooling would mean better long-term brain function for thousands of cardiac arrest survivors each year. The overall cost of rapid cooling per life-year saved is in the ballpark with kidney dialysis or the placement of automated external defibrillators in public places.