Impact of therapeutic hypothermia in the treatment of patients with out-of-hospital cardiac arrest from the J-PULSE-HYPO study registry

Background: Mild hypothermia is an effective therapy for patients with return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest. However, evidence of the effectiveness of therapeutic hypothermia (TH) remains unclear. Methods and Results: A multicenter registry in Japan (J-PULSE-HYPO study registry) was conducted to investigate the effectiveness of TH for post-resuscitation neurological dysfunction developing after out-of-hospital cardiac arrest from 14 institutions, between January 2005 and December 2009. The committee entrusted each hospital with the timing of cooling, cooling methods, target temperature, duration, and rewarming. There were 452 patients (375 men) enrolled into the registry. The mean age was 58.6±13.5 years. Initial electrocardiogram rhythm at the time of occurrence of the cardiac arrest showed 68.9% had ventricular fibrillation or pulseless ventricular tachycardia, 13.7% had pulseless electrical activity, and 9.1% had asystole. The median interval from the occurrence of cardiac arrest to ROSC was 26 min. The target core temperature during TH was 33.90.4°C and the mean duration of cooling was 31.513.9 h. Intra-aortic balloon pumping was used in 40.1% and percutaneous cardiopulmonary support in 22.6% of patients. At 30 days after cardiac arrest, the proportion of survival was 80.1% and the proportion of patients with favorable neurological functions, with a cerebral performance category score of 1 or 2, was 55.3%. Conclusions: The J-PULSE-HYPO study registry showed a clinical aspect of TH.