Extracorporeal resuscitation for refractory out-of-hospital cardiac arrest in adults: A systematic review of international practices and outcomes.

Aim: Extracorporeal resuscitation during cardiopulmonary resuscitation (ECPR) deploys rapid cardiopulmonary bypass to sustain oxygenated circulation until the return of spontaneous circulation (ROSC). The purpose of this systematic review is to address the defining elements and outcomes (quality survival and organ donation) of currently active protocols for ECPR in refractory out-of-hospital cardiac arrest (OHCA) of cardiac origin in adult patients. The results may inform policy and practices for ECPR and help clarify the corrresponding intersection with deceased organ donation.

Methods: We searched Medline, Embase, Cochrane and seven other electronic databases from 2005 to 2015, with no language restrictions. Internal validity and the quality of the studies reporting outcomes and guidelines were assessed. The review was included in the international prospective register of systematic reviews (Prospero, CRD42014015259).

Results: One guideline and 20 outcome studies were analyzed. Half of the studies were prospective observational studies assessed to be of fair to good methodological quality. The remainder were retrospective cohorts, case series, and case studies. Ages ranged from 16 to 75 years and initial shockable cardiac rhythms, witnessed events, and a reversible primary cause of cardiac arrest were considered favorable prognostic factors. CPR duration and time to hospital cannulation varied considerably. Coronary revascularization, hemodynamic interventions and targeted temperature management neuroprotection were variable. A total of 833 patients receiving this ECPR approach had an overall reported survival rate of 22%, including 13% with good neurological recovery. Additionally, 88 potential and 17 actual deceased organ donors were identified among the non-survivor population in 8 out of 20 included studies. Study heterogeneity precluded a meta-analysis preventing any meaningful comparison between protocols, interventions and outcomes.

Conclusions: ECPR is feasible for refractory OHCA of cardiac origin in adult patients. It may enable neurologically good survival in selected patients, who practically have no other alternative in order to save their lives with quality of life, and contribute to organ donation in those who die. Large, prospective studies are required to clarify patient selection, modifiable outcome variables, risk-benefit and cost-effectiveness.