A randomized controlled trial comparing the Arctic Sun to standard cooling for induction of hypothermia after cardiac arrest.

CONTEXT: Hypothermia improves neurological outcome for comatose survivors of out-of-hospital cardiac arrest. Use of computer controlled high surface area devices for cooling may lead to faster cooling rates and potentially improve patient outcome.

OBJECTIVE: To compare the effectiveness of surface cooling with the standard blankets and ice packs to the Arctic Sun, a mechanical device used for temperature management.

DESIGN, SETTING, AND PATIENTS: Multi-center randomized trial of hemodynamically stable comatose survivors of out-of-hospital cardiac arrest.

INTERVENTION: Standard post-resuscitative care inducing hypothermia using cooling blankets and ice (n=30) or the Arctic Sun (n=34).

MAIN OUTCOME MEASURES: The primary end point was the proportion of subjects who reached a target temperature within 4h of beginning cooling. The secondary end points were time interval to achieve target temperature (34 degrees C) and survival to 3 months.

RESULTS: The proportion of subjects cooled below the 34 degrees C target at 4h was 71% for the Arctic Sun group and 50% for the standard cooling group (p=0.12). The median time to target was 54 min faster for cooled patients in the Arctic Sun group than the standard cooling group (p<0.01). Survival rates with good neurological outcome were similar; 46% of Arctic Sun patients and 38% of standard patients had a cerebral performance category of 1 or 2 at 30 days (p=0.6).

CONCLUSIONS: While the proportion of subjects reaching target temperature within 4h was not significantly different, the Arctic Sun cooled patients to a temperature of 34 degrees C more rapidly than standard cooling blankets.