Understanding the ”Extra-Corporeal Membrane Oxygenation Gap" in Veno-Arterial Configuration for Adult Patients: Timing and Causes of Death. Defining the Veno-Arterial Extracorporeal Membrane Oxygenation Gap
Abstract Background Timing and causes of hospital mortality in adult patients undergoing veno-arterial extracorporeal membrane oxygenation (V-A ECMO) have been poorly described. Aim of the current review was to investigate the timing and causes of death of adult patients treated with V-A ECMO, and subsequently define the “V-A ECMO gap”, which represents the patients who are successfully weaned of ECMO but eventually die during hospital stay.Methods A systematic search was performed using electronic MEDLINE and EMBASE databases through PubMed. Studies reporting on adult V-A ECMO patients from January 1993 to October 2018 were screened. Timing, rates and causes of in-hospital mortality were analyzed.Results Sixty studies with 9,181 patients were included in this systematic review. Overall mortality was 37.6% during V-A ECMO support (reported by 60 studies) and 28.9% (57 studies) after weaning. Finally, 32.6% were discharged from hospital (60 studies). Most common causes of death on ECMO were multiple organ failure (MOF, 49.8%), followed by cardiac failure (20.6%) and neurological causes (15.7%). Most common causes of death after weaning were MOF (55.3%), followed by neurological complications (12.6%), persistent heart failure (10.7%) and pulmonary infections (6.8%).Conclusions More than one-third of adult V-A ECMO patients die during ECMO therapy. Additionally, almost one half of successfully weaned patients still decease during hospital stay, defining the “V-A ECMO gap”. Underreporting and lack of uniformity in reporting of important parameters remains problematic in ECMO research. Future studies should uniformly define timing and causes of death in V-A ECMO patients to better understand the effectiveness and complications of this therapy. Systematic review registration PROSPERO 2019 number CRD42019130815