Abstract 284: Impact of Target Core Temperature on Neurological Outcome of Cardiac Arrest Patients Treated With Therapeutic Hypothermia
Introduction: Therapeutic hypothermia improves neurological outcome in patients with out-of-hospital cardiac arrest. However, ideal target core temperature remains unclear. We investigated the effects of target core temperature on neurological outcome of cardiac arrest patients treated with therapeutic hypothermia.
Methods: We conducted a multi-center registry at 14 institutions to evaluate the effect of therapeutic hypothermia on out-of-hospital cardiac arrest between January 2005 and December 2009. The study committee entrusted each hospital with the timing of cooling, cooling methods, target temperature, duration, and rewarming rate. Enrolled patients were divided into the L group (32–33°C) and the M group (34–35°C) according to target core temperature, and neurological outcome was compared at hospital discharge. A favorable outcome was defined as a Cerebral Performance Category (CPC) of 1–2.
Results: A total of 452 patients were enrolled into the registry. Two patients were excluded because target temperature was unknown. The median interval from collapse to return of spontaneous circulation was 25 minutes. Between the L group (n=43) and the M group (n=407), the rates of survivors (77% vs. 77%) and favorable outcomes (60% vs. 55%) were not statistically different. As compared with the M group, the L group had significantly longer cooling time (43 hrs vs. 25 hrs, p=0.0005) and lower rate of core cooling method (28% vs. 50%, p=0.0056). The L group had significantly higher rates of inadequately controlled core temperature (49% vs. 29%, p=0.0073) and side effects of hypothermia (48% vs. 29%, p=0.014). Of the side effects, the rate of arrhythmia was significantly different (19% vs. 5%, p=0.0004).
Conclusions: This study indicated that target core temperature did not affect neurological outcome of cardiac arrest patients. In addition, the lower target core temperature may cause increase of side effects. To control core temperature adequately, further studies of cooling methods and management are needed.
- © 2010 by American Heart Association, Inc.