Variability in patient selection criteria across extracorporeal cardiopulmonary resuscitation (ECPR) systems: A systematic review

Background: : Across the world, many systems have implemented extracorporeal cardiopulmonary resuscitation (ECPR) as a potential treatment strategy for patients in refractory cardiac arrest. To date, there are no universally accepted criteria for patient selection for ECPR. We conducted a systematic review to explore the variability in patient eligibility criteria for ECPR across systems. Methods: : We searched the Cochrane Library(Wiley), EMBASE(OVID), and MEDLINE ALL (OVID) databases from inception to 5th February-2024 for all studies that described an ECPR system and where the system eligibility criteria was described. A combination of predetermined search terms was used to identify relevant articles. We conducted forward and backward citation tracking to identify any further relevant articles. Results: : Our search identified 12,503 articles of which 167 articles were found to be potentially eligible. Seventy-seven articles were further excluded as they described the same ECPR system as another study. We finally included 90 studies describing a total of 93 ECPR systems. The eligibility criteria for ECPR differed among the included systems. Across systems, ECPR eligibility criteria included age (n=75, 80.7%), arrest witnessed status (n=64, 68.8%), any initial rhythm (n=55, 59.1%), and bystander CPR (n=33, 35.5%). Within criteria, we observed marked variability. The age cut-off varied from 50 to 80 years, with the most common age cut-off being 75 years and 18 (19.3%) systems having no cut-off. Whilst most systems limited ECPR to shockable rhythms (n=28,30.1%), some systems included shockable rhythms and/or PEA only (n=10,10.8%). Conclusion: : We observed marked variability across systems in the eligibility criteria for potential ECPR patients. There is a need for further work to identify the optimum ECPR selection criteria. Review registration: PROSPERO (CRD42023451109).