Extracorporeal cardiopulmonary resuscitation for refractory cardiac arrest: a scoping review

Background Extracorporeal cardiopulmonary resuscitation (ECPR) is an emerging concept in cardiac arrest and cardiopulmonary resuscitation. Recent research has documented a significant improvement in favorable outcomes, notable survival to discharge, and neurologically intact survival. Objectives The present study undertakes a scoping review to summarize the available evidence by assessing the use of ECPR, compared with no ECPR or the standard of care, for adult patients who sustain cardiac arrest in any setting, in studies which record survival and neurologic outcomes. Methods This review followed the PRISMA extension for scoping reviews (PRISMA‐ScR) guidelines. Four online databases were used to identify papers published from database inception to July 12, 2020. We selected 23 observational studies from Asia, Europe, and North America that used survival to discharge or neurologically intact survival as a primary or secondary endpoint variable in patients with cardiac arrest refractory to standard treatment. Results Twenty‐three observational studies were included in the review. Eleven studies were of out‐of‐hospital cardiac arrest, 7 studies were of in‐hospital cardiac arrest, and 5 studies included mixed populations. Ten studies reported long‐term favorable neurological outcomes (ie, Cerebral Performance Category score of 1 – 2 at 3 months [n = 3], 6 months [n = 3], and 1 year [n = 4]), of which only 4 had statistical significance at 5% significance levels. Current knowledge is mostly drawn from single‐center observations, with most of the evidence coming from case series and cohort studies, hence is prone to publication bias. No randomized control trials were included. Conclusions This scoping review highlights the need for high‐quality studies to increase the level of evidence and reduce knowledge gaps to change the paradigm of care for patients with shock‐refractory cardiac arrest.