It sounds cold, but icing down patients who have just had a heart stoppage may boost their survival chances and prevent brain damage in those who do pull through, two new studies show.
A heart attack, near-drowning, or other misfortune that leaves a person pulseless for even a few minutes can damage the brain because halted blood flow starves brain tissues of needed oxygen. Ironically, cardiac resuscitation and the abrupt restoration of blood flow often cause a second round of damage to the brain.
Experiments in animals during the past 2 decades showed that cooling the body after a shutdown of the heart prevented much of this secondary damage. Lowering body temperature, thereby cooling the blood, slows processes in the brain that ignite harmful biochemical chain reactions.
Cooling was tried as a heart attack treatment in the 1950s. After mixed results, doctors shelved the concept. In fact, warming patients during some surgeries has proven beneficial (SN: 4/12/97,