AURORA, Colo., Nov. 24 (UPI) -- Researchers found neurological function can be protected in heart attack patients who remain in a coma with a "nonshockable" heartbeat by lowering their body temperature.
Previous studies have shown patients with shockable heart rhythms can benefit from therapeutic hypothermia to protect the brain from lack of blood flow when it has been drastically reduced as a result of cardiac arrest.
Researchers said, however, there had not been much research to support using the method with those whose heartbeats cannot be jump-started by ventricular fibrillation.
The therapy involves applying cooling wraps to patients in order to drop their temperature to 91.4 degrees Fahrenheit, which reduces damage to the brain after a heart attack, though researchers are unsure why.
"Neurologic injury after cardiac arrest is devastating," said Dr. Sarah Perman, an assistant professor of emergency medicine at the University of Colorado School of Medicine, in a press release. "We have one chance to give some form of neuroprotection, and that's immediately after the arrest."
The researchers identified 519 heart attack patients with non-shockable initial heart rhythms in the Penn Alliance for Therapeutic Hypothermia registry between 2000 and 2013.
Patients who received therapeutic hypothermia were 2.8 times as likely to survive to discharge from the hospital and 3.5 times more likely to have positive neurological outcomes than people who did not have their temperatures lowered.
"Our resources right now are not extensive and our outcomes are still fairly grim," Perman said. "Therapeutic hypothermia is one therapy we do have in our arsenal, and if a patient is comatose after arrest, it's very important to consider applying this therapy, specifically in patients who are neurologically injured," she said.
The study is published in the journal Circulation.