Extracorporeal membrane oxygenation for critically ill adults

Background Extracorporeal membrane oxygenation (ECMO) is a form of life support that targets the heart and lungs. Extracorporeal membrane oxygenation for severe respiratory failure accesses and returns blood from the venous system and provides non‐pulmonary gas exchange. Extracorporeal membrane oxygenation for severe cardiac failure or for refractory cardiac arrest (extracorporeal cardiopulmonary resuscitation (ECPR)) provides gas exchange and systemic circulation. The configuration of ECMO is variable, and several pump‐driven and pump‐free systems are in use. Use of ECMO is associated with several risks. Patient‐related adverse events include haemorrhage or extremity ischaemia; circuit‐related adverse effects may include pump failure, oxygenator failure and thrombus formation. Use of ECMO in newborns and infants is well established, yet its clinical effectiveness in adults remains uncertain. Objectives The primary objective of this systematic review was to determine whether use of veno‐venous (VV) or venous‐arterial (VA) ECMO in adults is more effective in improving survival compared with conventional respiratory and cardiac support. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid) and EMBASE (Ovid) on 18 August 2014. We searched conference proceedings, meeting s, reference lists of retrieved articles and databases of ongoing trials and contacted experts in the field. We imposed no restrictions on language or location of publications. Selection criteria We included randomized controlled trials (RCTs), quasi‐RCTs and cluster‐RCTs that compared adult ECMO versus conventional support. Data collection and analysis Two review authors independently screened the titles and s of all retrieved citations against the inclusion criteria. We independently reviewed full‐text copies of studies that met the inclusion criteria. We entered all data extracted from the included studies into Review Manager. Two review authors independently performed risk of bias assessment. All included studies were appraised with respect to random sequence generation, concealment of allocation, blinding of outcome assessment, incomplete outcome data, selective reporting and other bias. Main results We included four RCTs that randomly assigned 389 participants with acute respiratory failure. Risk of bias was low in three RCTs and high in one RCT. We found no statistically significant differences in all‐cause mortality at six months (two R