Introduction
It is unknown how awake prone positioning was practiced in patients with COVID–19 in the second wave of the national outbreak in the Netherlands.

Objectives
We studied the practice of awake prone positioning in COVID–19 patients admitted to the ICU because of acute hypoxemic respiratory failure, and determined associations with demographics and outcomes.

Methods
Investigator–initiated, national, multicenter study in 16 hospitals in the Netherlands. Patients that received awake prone positioning were compared to patients that did not receive this intervention. The primary endpoint was a composite of various aspects of awake prone positioning practice. The secondary endpoint was ‘treatment failure’, a composite of intubation for invasive ventilation and death before day 28. We used propensity matching to control for observed confounding factors.

Results
In 546 non–intubated patients, awake prone positioning was used in 88 (16.1%) patients, within median 1 [0 to 2] days after ICU admission, for median 1.0 [0.8–1.4] days and median 12.0 [8.4–14.5] hours per day. High–flow oxygen therapy was the most often used oxygen interface at start of awake prone positioning. Patients in the awake prone positioning group less often had a history of cardiovascular disease. In unmatched analysis, treatment failure occurred more often in patients that received awake prone positioning (HR, 1.80 [1.41–2.31]; P<0.001); in matched analysis, differences remained present, but did no longer reach statistical significance (HR, 1.17 [0.87-1.59]; P=0.30).

Conclusions
In this national cohort of COVID–19 patients in the second wave of the national outbreak, awake prone positioning was used in one in six patients. Awake prone positioning started early, but was often discontinued because of need for intubation. Patients that received awake prone positioning had higher risk for treatment failure.