Role of proning and positive end-expiratory pressure in COVID-19

Table 1 Acute respiratory distress syndrome definition

ARDS definition
Onset	Within 1 wk of a known clinical insult or new or worsening respiratory symptoms
Chest imaging	Bilateral opacities – not fully explained by effusions, lobar/lung collapse, or nodules on either Chest X-ray or computed X-ray tomography scan
Origin of edema	Respiratory failure not fully explained by heart failure or fluid overload; Need objective assessment (e.g., echocardiogram) to exclude hydrostatic edema if no risk factors present
Oxygenation	PaO2/FiO2 ratio < 300 with PEEP > 5 cm/H2O

ARDS: Acute respiratory distress syndrome; PEEP: Positive end-expiratory pressure.