Abstract 338: Therapeutic Hypothermia for Patients With Post-Resuscitation Shock After Out-of-Hospital Cardiac Arrest

Abstract

Background: Animal data have suggested a beneficial effect of therapeutic hypothermia following return of spontaneous circulation (ROSC) (post-ROSC cooling) in cardiogenic shock, but there are few human studies of patients with post-resuscitation shock who were treated with post-ROSC cooling. METHODS: From the J-PULSE HYPO registry, a multi-center registry in Japan, we selected the patients who met the following inclusion criteria: bystander-witnessed cardiac arrest due to ventricular fibrillation (VF), target core temperature of 32-34°C, and cooling duration of 12-72 hours. Study patients were divided into two groups based on hemodynamic status. The post-resuscitation shock group consisted of patients with systolic blood pressure < 90 mmHg and/or mechanical circulation support. The remaining patients constituted the non-shock group. The primary endpoint was favorable neurological outcome at 30 days after cardiac arrest. Results: Of the 452 adult patients treated with post-ROSC cooling, 292 met the inclusion criteria; 149 (51%) were post-resuscitation shock and 143 (49%) were non-shock. No significant difference was observed between the two groups in the frequency of 30-day favorable neurological outcome (63% [94/149] post-resuscitation shock group vs. 68% [97/143] non-shock group; p=0.39). However, the median collapse-to-ROSC interval was significantly longer in the post-resuscitation shock group than in the non-shock group (27 minutes vs. 20 minutes, p<0.001). In the quartiles of collapse-to-ROSC interval and 30-day favorable neurological outcome, both groups exhibited high frequencies of 30-day favorable neurological outcome in Quartile 1, in which the collapse to ROSC interval was 15 minutes or less (93% post-resuscitation shock group vs. 87% non-shock group, p=0.40), and a significant decrease in 30-day favorable neurological outcome was found in each group as the quartile value of collapse-to-ROSC interval increased (p<0.001, respectively). The 30-day favorable neurological outcome in each Quartile 2, 3 and 4 did not differ between the two groups. Conclusion: Due to the effects of post-ROSC cooling, post-resuscitation shock patients were able to achieve the same level of neurological benefit as non-shock patients.