ECMO in COVID-19 patients
The urgent need to treat critically ill patients with an unknown evolution has forced cardiovascular surgeons to decide whether or not to implant an ECMO system when the scientific evidence available, in the context of COVID-19, was sparse and weak. Only a few published cases from China were available at the beginning of the pandemic (23, 24).
To add some confusion, concerns were raised about the possible deleterious effect of ECMO in this disease; it is know that during ECMO support there are substantial decreases in number and function of some lymphocyte populations, as well as consistently high IL-6 concentrations inversely correlated with survival. Prudence advised to consider the immunological status of patients when selecting ECMO candidates and seriously tracking both lymphocyte count and IL-6 during support.