Abstract 347: The Effect of Targeted Temperature Management at 34 °C and 36 °C on Day-30 Neurological Outcomes in Out-of-hospital Cardiac Arrest Patients

Abstract

Introduction: Targeted temperature management (TTM) has established evidence for improving neurological outcomes in cardiac arrest patients who sustained coma after return of spontaneous circulation (ROSC). The target temperature has been recommended to be between 32 and 36 °C. However optimal temperature remains unestablished. This study aimed to assess the relationship between target temperature and neurological outcome by using the Japanese nationwide registry. Methods: This retrospective observational cohort study was based on the Japanese association for acute medicine - out-of-hospital cardiac arrest (JAAM-OHCA) registry during 2014 to 2017. Our study included all initial rhythms and any cause of OHCA patients and excluded age < 18 and Glasgow Coma Scale score > 8. The primary outcome was 30 day favorable neurological outcome, defined as cerebral performance category (CPC) scale 1 and 2. First, to clarify the efficacy of TTM, the neurological outcome was compared whether patients received TTM or not. Next, to evaluate the relationship between neurological outcome and target temperature on TTM, the neurological outcome was compared hypothermia (34 °C) group with normothermia (36 °C) group . Single and multivariable logistic regression analysis was performed. Results: The study included 9930 patients. Of these, 1184 (11.9%) patients received TTM. Favorable neurological outcome was more present in TTM group than in no TTM group (39.7% vs. 4.3%, odds ratio [OR] 14.6, 95% confidence interval [CI] 12.5-17.1, p<0.001). Multivariable analysis showed TTM was associated with favorable neurological outcome (OR 1.6, 95%CI 1.1-2.3, p<0.001). Of TTM group, 801 (68.5%) patients received hypothermia management and 242 (20.7%) patients received normothermia management. Favorable neurological outcome was more present in the hypothermia group than in the normothermia group (42.6% vs. 34.3%, OR 1.42, 95% CI 1.1-1.9, p=0.022). However, the neurological outcome did not differ between these two groups (OR 0.84, 95%CI 0.46-1.5, p<0.57). Conclusions: TTM was significantly associated with favorable neurological outcome. However, neurological outcome was not associated with target temperature on TTM.