Prone positioning of patients with moderate hypoxaemia due to covid-19: multicentre pragmatic randomised trial (COVID-PRONE)
Authors: Fralick Michael , Colacci Michael , Munshi Laveena , Venus Kevin , Fidler Lee , Hussein Haseena , Britto Karen , Fowler Rob , da Costa Bruno R , Dhalla Irfan , Dunbar-Yaffe Richard , Branfield Day Leora , MacMillan Thomas E , Zipursky Jonathan , Carpenter Travis , Tang Terence , Cooke Amanda , Hensel Rachel , Bregger Melissa , Gordon Alexis , Worndl Erin , Go Stephanie , Mandelzweig Keren , Castellucci Lana A , Tamming Daniel , Razak Fahad , Verma Amol A 
Published: March 2022

Objectives

To assess the effectiveness of prone positioning to reduce the risk of death or respiratory failure in non-critically ill patients admitted to hospital with covid-19.

Design

Multicentre pragmatic randomised clinical trial.

Setting

15 hospitals in Canada and the United States from May 2020 until May 2021.

Participants

Eligible patients had a laboratory confirmed or a clinically highly suspected diagnosis of covid-19, needed supplemental oxygen (up to 50% fraction of inspired oxygen), and were able to independently lie prone with verbal instruction. Of the 570 patients who were assessed for eligibility, 257 were randomised and 248 were included in the analysis.

Intervention

Patients were randomised 1:1 to prone positioning (that is, instructing a patient to lie on their stomach while they are in bed) or standard of care (that is, no instruction to adopt prone position).

Main outcome measures

The primary outcome was a composite of in-hospital death, mechanical ventilation, or worsening respiratory failure defined as needing at least 60% fraction of inspired oxygen for at least 24 hours. Secondary outcomes included the change in the ratio of oxygen saturation to fraction of inspired oxygen.

Results

The trial was stopped early on the basis of futility for the pre-specified primary outcome. The median time from hospital admission until randomisation was 1 day, the median age of patients was 56 (interquartile range 45-65) years, 89 (36%) patients were female, and 222 (90%) were receiving oxygen via nasal prongs at the time of randomisation. The median time spent prone in the first 72 hours was 6 (1.5-12.8) hours in total for the prone arm compared with 0 (0-2) hours in the control arm. The risk of the primary outcome was similar between the prone group (18 (14%) events) and the standard care group (17 (14%) events) (odds ratio 0.92, 95% confidence interval 0.44 to 1.92). The change in the ratio of oxygen saturation to fraction of inspired oxygen after 72 hours was similar for patients randomised to prone positioning and standard of care.

Conclusion

Among non-critically ill patients with hypoxaemia who were admitted to hospital with covid-19, a multifaceted intervention to increase prone positioning did not improve outcomes. However, wide confidence intervals preclude definitively ruling out benefit or harm. Adherence to prone positioning was poor, despite multiple efforts to increase it. Subsequent trials of prone positioning should aim to develop strategies to improve adherence to awake prone positioning.

Study registration

ClinicalTrials.govNCT04383613.