Extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest: A meta-analysis of randomized controlled trials

Introduction: Extracorporeal cardiopulmonary resuscitation (ECPR) is a resuscitation method for patients with refractory out-of-hospital cardiac arrest (OHCA). However, evidence from randomized controlled trials (RCTs) is lacking.

Methods: We searched several electronic databases until March 2023 for RCTs comparing ECPR with conventional CPR in OHCA patients. RevMan 5.4 was used to pool risk ratios (RR) with 95% confidence intervals (CIs).

Results: A total of four RCTs were included. The results of our meta-analysis showed no statistically significant benefit of ECPR regarding mid-term survival (RR 1.21; 95% CI 0.64 to 2.28; I² = 48%; p = .55). We found a significant improvement with ECPR in mid-term favorable neurological outcome (RR 1.59; 95% CI 1.09 to 2.33; I² = 0%; p = .02). There was no significant difference between ECPR and conventional CPR in long-term survival (RR 1.32; 95% CI 0.18 to 9.50; I² = 64%; p = .79), and long-term favorable neurological outcome (RR 1.47; 95% CI 0.89 to 2.43; I² = 25%; p = .13). There was an increased incidence of adverse events in the ECPR group (RR 3.22; 95% CI 1.18 to 8.80; I² = 63%; p = .02).

Conclusion: ECPR in OHCA patients was not associated with improved survival or long-term favorable neurological outcome but did improve favorable neurological outcome in the mid-term. However, these results are likely underpowered due to the small number of available RCTs. Large-scale confirmatory RCTs are needed to provide definitive conclusions.