COVID-19 and Extracorporeal Membrane Oxygenation.

Introduction: Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has recently and rapidly emerged and developed into a global pandemic. In SARS-CoV-2 patients with refractory respiratory failure, there may be a role for veno-venous extracorporeal membrane oxygenation (V-V ECMO) as a life-saving rescue intervention.

Methods: This review summarizes the evidence gathered until June 12, 2020; electronic databases were screened for pertinent reports on coronavirus and V-V ECMO. Search was conducted by two independent investigators; keywords used were SARS-CoV-2, COVID-19, ECMO, and extracorporeal life support (ECLS).

Results: Many patients with COVID-19 experience moderate symptoms and a relatively quick recovery, but others must be admitted into the intensive care unit due to severe respiratory failure and often must be mechanically ventilated. Further deterioration may require institution of extracorporeal oxygenation. Infection mechanisms may trigger "cytokine storm," an inflammatory disorder notable for multi-organ system failure; together with other metabolic and hematological changes, these amplify the changes pertinent to ECMO therapy, often exaggerating blood coagulation disorders. Thirty-two studies were found describing experiences with ECMO in the treatment of COVID-19. Of 4,912 COVID-19 patients, 2,119 (43%) developed ARDS and 2,086 (42%) were transferred to the ICU; 1,015 patients (21%) were treated with ECMO. While in an overall cohort, observed mortality was 640 (13%), the mortality within ECMO subgroups reached up to 34.6% (range 0-100%).

Conclusion: The efficacy of ECMO treatment for COVID-19 is largely dependent on the expertise of the center in ECLS due to the interplay between the changes in hematological and inflammatory modulators associated with both COVID-19 and ECMO. In order to support gas exchange during early infection with SARS-CoV-2, ECMO has a strong rationale for the treatment of the most critically ill patients. Due to the limited resources during a global pandemic, ECMO should be reserved for only the most severe cases of COVID-19.