Early Cooling in Cardiac Arrest May Improve Survival

Rapidly cooling a person during cardiac arrest may improve their chance of survival without brain damage, according to a new study.

Researchers at the Karolinska Institute (Stockholm, Sweden) and 14 other centers across Europe randomized 200 adults going into witnessed cardiac arrest to receive either standard cardiopulmonary resuscitation (CPR) or CPR with nasal cooling started as soon as possible during the arrest, with ongoing CPR. All patients who survived to hospitalization were further cooled according to standard criteria. Eighteen patients were excluded from the analysis because a "do-not-resuscitate” order was found or there was a noncardiac reason for their cardiac arrest. In the 182 patients reported, 83 were randomized to receive nasal cooling and 99 received standard care.


The researchers found that 46.7% of all those cooled survived to hospital discharge, compared with 31% of those receiving standard care; additionally, 36.7 % of those cooled were in good neurological condition on hospital discharge, compared with just 21.4% of those receiving standard care. In 137 patients in whom resuscitation efforts began within 10 minutes of cardiac arrest, 59.1% of those cooled survived to hospital discharge, compared with 29.4% of those receiving standard care; 45.5% of those cooled were neurologically intact at hospital discharge, compared with 17.6% percent of those receiving standard care. In a time analysis, patients who received a combination of early CPR started within six minutes of collapse and cooling had the best outcomes. The study was presented at the American Heart Association (AHA) scientific sessions held during November 2009 in Orlando (FL, USA).

"Our results show that the earlier you can do the cooling, the better. When resuscitation efforts were delayed, there was no significant difference in survival,” said lead author Maaret Castrén, M.D., a professor of emergency medicine. "We now have a method that is safe and can be started within minutes of cardiac arrest to minimize damage during this very critical period.”

The researchers in the Preresuscitation Intranasal Cooling Effectiveness (PRINCE) study used a new device, the RhinoChill, a noninvasive device that introduces coolant through nasal prongs. The system is battery-powered, and requires no refrigeration, making it suitable for emergency medical technicians in the field to use while a person is receiving CPR. The RhinoChill is a product of BeneChill (San Diego CA, USA); it has received the European Community (CE) marking.

Related Links:
Karolinska Institute
BeneChill