Predictors of favourable neurological outcomes in a territory-first extracorporeal cardiopulmonary resuscitation programme

Abstract

Background: Extracorporeal cardiopulmonary resuscitation (E-CPR) is an alternative resuscitation method that has been associated with better survival and neurological outcomes in both in-hospital cardiac arrest (IHCA) and out-of-hospital cardiac arrest (OHCA) compared with conventional cardiopulmonary resuscitation (CPR). This study aimed to report the results of the territory-first E-CPR programme at Queen Mary Hospital, and identify factors that predict favourable patient outcomes. Methods: This is a single centre, retrospective analysis of all patients who had OHCA or IHCA and were managed with E-CPR from 2012 to 2020. The outcome measures were survival with good neurological outcome, defined as Cerebral Performance Categories 1 or 2 at 3 months, and 30-day survival. Results: From 2012 to 2020, a total of 102 patients received E-CPR: 48 (47.1%) were patients who had OHCA, and 54 (52.9%) from IHCA. 63 (61.8%) patients were diagnosed with myocardial infarction, and 11 (10.8%) were diagnosed with acute myocarditis. The overall hospital survival was 24.5% (n=25), while intensive care unit survival was 31.4% (n=32). 19 (18.6%) patients survived with favourable neurological outcome. Having a shockable arrest rhythm at presentation was the strongest predictor of good neurological outcome in both univariate (P<0.001) and multivariate analysis (odds ratio=7.84; 95% confidence interval=1.63-37.60; P=0.010). Patients with good neurological outcome were also more likely to have received defibrillation during E-CPR (P=0.006), lower aspartate aminotransferase (AST) levels within 24 hours after E-CPR (P=0.003), myocardial infarction as the cause of cardiac arrest (P=0.026), and percutaneous coronary intervention (PCI) after E-CPR (P=0.007). Conclusion: Hong Kong’s first territory-wide E-CPR programme achieved a favourable survival with good neurological outcome of 18.6%, which is comparable to internationally reported outcomes. Patients who had a shockable rhythm at presentation, defibrillation during E-CPR, low AST values in the first 24 hours, myocardial infarction as the cause of cardiac arrest, or PCI after E-CPR had better neurological outcomes.