COVID-19-related acute respiratory distress syndrome treated with veno-venous extracorporeal membrane oxygenation and programmed multi-level ventilation: a case report.

We report a patient with severe coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS) treated with veno-venous extracorporeal membrane oxygenation (VV ECMO) and programmed multi-level ventilation (PMLV). VV ECMO as a treatment modality for severe ARDS has been described multiple times as a rescue therapy for refractory hypoxemia. It is well known that conventional ventilation can cause ventilator-induced lung injury. Protective ventilation during VV ECMO seems to be beneficial, translating to using low tidal volumes, prone positioning with general concept of open lung approach. However, mechanical ventilation is still required as ECMO per se is usually not sufficient to maintain adequate gas exchange due to hyperdynamic state of the patient and limitation of blood flow via VV ECMO. This report describes ventilation strategy using PMLV during "resting" period of the lung. In short, PMLV is a strategy for ventilating non-homogenous lungs that incorporates expiratory time constants and multiple levels of positive end-expiratory pressure. Using this approach, most affected acute lung injury/ARDS areas can be recruited, while preventing overdistension in healthy areas. To our knowledge, case report using such ventilation strategy for lung resting period has not been previously published.