Abstract 169: Association Between Time to First Administration of Epinephrine After Defibrillation and Outcome in Out-Of-Hospital Cardiac Arrest Patients With Shockable Rhythm

Abstract

Introduction: In out-of-hospital cardiac arrest (OHCA) patients during shockable rhythm, the epinephrine administration after second defibrillation is recommended by the 2015 ILCOR/CoSTR guidelines. However, there is insufficient evidence regarding the proper timing of epinephrine administration particularly in relation to defibrillation. Hypothesis: The timing of epinephrine after first defibrillation (D-E interval) was associated with clinical outcome in OHCA patients. Methods: Between 2011 and 2016, we enrolled 753,025 OHCA patients from nationwide prospective population-based registry in Japan. Following exclusion criteria, a total of 1,559 patients with witnessed by bystanders and shockable rhythm on the initial electrocardiogram who administrated epinephrine after defibrillation by emergency medical service personnel and obtained return of spontaneous circulation in prehospital setting were eligible for the study. We evaluated the association between D-E interval and favorable neurological outcome (cerebral performance category: 1 or 2) at 30 days. To evaluate predictor for better neurological outcome, study patients were categorized as every 2 minutes up to 20 minutes, and more than 20 minutes. Results: Patients with favorable neurological outcome were 22% (N=348). Patients with favorable neurological outcome had a shorter D-E interval than those with non-favorable neurological outcome (7.9±4.1vs 10.2±5.3 min, p<0.001). Multivariate logistic regression analysis showed that D-E interval at more than 10 minutes, when D-E interval at 2 to 3 minutes as defined reference, was a significant predictor for non-favorable neurological outcome ( Table ). Conclusion: Delayed epinephrine administration after first defibrillation (D-E interval >10 minutes) was significantly associated with non-favorable neurological outcome.