Patients admitted to hospital with severe breathing difficulties due to COVID-19 are less likely to need a breathing tube (endotracheal intubation) if they lie face down in a prone position, but the position's effect on mortality or other outcomes is inconclusive, suggests an in-depth analysis of the latest evidence published by The BMJ.
The review included 17 suitable trials involving 2,931 non-intubated COVID patients who were able to breathe without mechanical assistance and who spent an average of 2.8 hours per day lying prone, or on their stomachs.
The authors were particularly interested in gathering evidence from studies that used prone positioning when patients were awake. High-certainty evidence from 14 trials showed that awake prone positioning reduced the risk of endotracheal intubation compared with usual care (24.2% with awake prone positioning v 29.8% with usual care). This translates to 55 fewer intubations per 1,000 patients (95% confidence interval, 19 to 87 fewer intubations), the authors said.
Awake prone positioning was commonly used in the first months of the COVID-19 pandemic.
Thirteen trials examined awake prone positions in the context of mortality outcomes, and they did not show a significant difference in mortality between the two groups (15.6% with awake prone positioning v 17.2% with usual care).
"Awake prone positioning compared with usual care reduces the risk of endotracheal intubation in adults with hypoxemic respiratory failure due to covid-19 but probably has little to no effect on mortality or other outcomes," the authors wrote.
In a related editorial, four medical experts from Toronto write, "Several unanswered questions remain, including the ideal daily duration of treatment, the level of hypoxaemia that should prompt prone positioning, and how best to improve patient comfort and encourage adherence. These questions may never be answered definitively in patients with covid-19 as, fortunately, far fewer are experiencing hypoxaemic respiratory failure or critical illness."