Hemodynamic oxygenator exchange-related effects during veno-venous extracorporeal membrane oxygenation for the treatment of acute SARS-CoV-2 respiratory distress syndrome

Abstract

Few patients with coronavirus disease 2019-associated severe acute respiratory distress syndrome (ARDS) require veno-venous extracorporeal membrane oxygenation (VV-ECMO). Prolonged VV-ECMO support necessitates repeated oxygenator replacement, increasing the risk for complications. Transient hypoxemia, induced by VV-ECMO stop needed for this procedure, may induce transient myocardial ischemia and acutely declining cardiac output in critically ill patients without residual pulmonary function. This is amplified by additional activation of the sympathetic nervous system (tachycardia, pulmonary vasoconstriction, and increased systemic vascular resistance). Immediate reinjection of the priming solution of the new circuit and induced acute iatrogenic anemia are other potentially reinforcing factors. The case of a critically ill patient presented here provides an instructive illustration of the hemodynamic relationships occurring during VV-ECMO support membrane oxygenator exchange.

Keywords: ARDS; COVID-19; ECMO circuit; hypoxemia; membrane oxygenator replacement; veno-venous extracorporeal membrane oxygenation.

Figure 1.

Monitoring immediately after membrane oxygenator and circuit exchange. (a) Electrocardiogram showing tachycardia, large peaked T waves and ST segment elevation (red circle). (b) Simultaneous blood pressure drop of the continuous invasive radial measurement (red circle). (c) Drop in continuous end-tidal CO2 monitoring (red circle).