Rationale and objectives: Prone positioning as a complement to oxygen therapy to treat hypoxaemia in coronavirus disease 2019 (COVID-19) pneumonia in spontaneously breathing patients has been widely adopted, despite a lack of evidence for its benefit. We tested the hypothesis that a simple incentive to self-prone for a maximum of 12 h per day would decrease oxygen needs in patients admitted to the ward for COVID-19 pneumonia on low-flow oxygen therapy.

Methods: 27 patients with confirmed COVID-19 pneumonia admitted to Geneva University Hospitals were included in the study. 10 patients were randomised to self-prone positioning and 17 to usual care.

Measurements and main results: Oxygen needs assessed by oxygen flow on nasal cannula at inclusion were similar between groups. 24 h after starting the intervention, the median (interquartile range (IQR)) oxygen flow was 1.0 (0.1–2.9) L·min⁻¹ in the prone position group and 2.0 (0.5–3.0) L·min⁻¹ in the control group (p=0.507). Median (IQR) oxygen saturation/fraction of inspired oxygen ratio was 390 (300–432) in the prone position group and 336 (294–422) in the control group (p=0.633). One patient from the intervention group who did not self-prone was transferred to the high-dependency unit. Self-prone positioning was easy to implement. The intervention was well tolerated and only mild side-effects were reported.

Conclusions: Self-prone positioning in patients with COVID-19 pneumonia requiring low-flow oxygen therapy resulted in a clinically meaningful reduction of oxygen flow, but without reaching statistical significance.