Does proning on NIV improve oxygenation?

Proning intubated patients with acute respiratory distress syndrome (ARDS) is an established practice to improve oxygenation temporarily. We present two cases of patients on our intensive care unit with ARDS, on non-invasive ventilation (NIV), in whom proning improved oxygenation at a stage when intubation was the next step. We discuss the mechanisms by which proning improves oxygenation as well as the potential risks proning on NIV brings, for which we make specific recommendations.