Awake prone positioning for hypoxaemic respiratory failure: past, COVID-19 and perspectives.

Prone positioning reduces mortality in the management of intubated patients with moderate-to-severe acute respiratory distress syndrome. It allows improvement in oxygenation by improving ventilation/perfusion ratio mismatching.Because of its positive physiological effects, prone positioning has also been tested in non-intubated, spontaneously breathing patients, or "awake" prone positioning.