Positive end-expiratory pressure in COVID-19-related ARDS: Do not forget the airway closure.

Airway closure is a physiological phenomenon in which the distal airways are obstructed when the airway pressure drops below the airway opening pressure. We assessed this phenomenon in 27 patients with coronavirus disease 2019-related acute respiratory distress syndrome. Twelve (44%) patients had an airway opening pressure above 5 cmHO. The median airway opening pressure was 8 cmHO (interquartile range, 7-10), with a maximum value of 17 cmHO. Three patients had a baseline positive end-expiratory pressure lower than the airway opening pressure.