Association Between the Rewarming Duration and Neurological Outcomes after Extracorporeal Cardiopulmonary Resuscitation Followed by Targeted Temperature Management for Out-of-Hospital Cardiac Arrests: A Secondary Analysis of the SAVE-J II Study

There are no studies examining the association between rewarming durations and neurological outcomes after extracorporeal cardiopulmonary resuscitation (ECPR) followed by targeted temperature management (TTM) for patients with out-of-hospital cardiac arrest (OHCA). This study aimed to examine the association between rewarming durations and neurological outcomes after ECPR with TTM for patients with OHCA. This was a secondary analysis of the Advanced Life Support Study Registry for Ventricular Fibrillation with Extracorporeal Circulation in Japan study, a retrospective, multicenter study. Patients with OHCA who underwent ECPR and completed a TTM of 34°C and <34°C were included. Favorable neurological outcomes (cerebral performance categories 1-2) and survival upon hospital discharge were the primary outcomes. In total, 407 patients were included, with favorable neurological outcomes upon hospital discharge in 106 patients. The numbers of patients with rewarming durations of <24 hours, 24 hours, and >24 hours were 178, 133, and 96, respectively. In the multivariable analysis, a rewarming duration of <24 hours was not significantly associated with favorable neurological outcomes [odds ratio (OR): 1.06, 95% confidence interval (CI): 0.60-1.87, <i>p</i> = 0.84] or survival (OR: 0.96, 95% CI: 0.58-1.57, <i>p</i> = 0.86) compared with that of 24 hours, and that of <24 hours was not significantly associated with favorable neurological outcomes (OR: 0.74, 95% CI: 0.40-1.71, <i>p</i> = 0.56) or survival (OR: 0.74, 95% CI: 0.42-1.28, <i>p</i> = 0.38) than that of >24 hours. A rewarming duration of <24 hours in TTM after ECPR for OHCA was not significantly associated with favorable neurological outcomes or survival than that of 24 hours or >24 hours.