Mechanical Ventilation in COVID-19 Patients Supported With ECMO in Wenzhou, China: A Retrospective Study

Abstract BackgroundThe function of Extracorporeal membrane oxygenation (ECMO) is to maintain cardiopulmonary function in critical patients diagnosed with Coronavirus (COVID-19). Under the protection of ECMO, we recorded and analyzed the results of ventilator treatment following the adjustment of ventilator settings.MethodsThis retrospective study enrolled six patients who received ECMO treatment. Clinical, laboratory and radiological characteristics, time of spontaneous respiration, and static lung compliance (CLst) were all recorded. Positive end-expiratory pressure (PEEP) and oxygen concentration (FIO2) were adjusted to record changes in oxygen saturation (SpO2), tidal volume (TV), peak airway pressure, and blood gas analysis. ResultsDuring analysis, one patient died of COVID-19 within 28 days, and two patients were successfully weaned off mechanical ventilation and ECMO. Patients with an improved condition have a longer time of spontaneous respiration and better CLst than those who worsen. With an instantaneous increase in FIO2 alone or a combination of PEEP / FIO2, SpO2 and partial pressure of oxygen (PaO2) both increased, but no significant change was observed in PaCO2, PaO2/FIO2 and TV. With an instantaneous increase of PEEP alone, SpO2 , PaO2, PaCO2, PaO2/FIO2 and TV showed no significant change. ConclusionsECMO can save some patients’ lives, but some patients will still suffer multiple organ failure and even death. The time of spontaneous respiration, CLst and TV may be a good choice for evaluating patients' lung situations. Increased PEEP may not significantly reduce lung exudation in COVID-19 patients supported by ECMO but further expand the over-expanded alveoli.