Prone Positioning in a North American Cohort of Hypoxemic Patients on Mechanical Ventilation

Objective: Use of prone positioning increased among mechanically ventilated patients during the COVID-19 pandemic, but it is unknown whether implementation of this life-saving intervention was sustained. Thus, we aimed to evaluate peri-pandemic trends in proning use. Design: We conducted a retrospective cohort study of proning use among mechanically ventilated adults, with proning rates compared across pre-pandemic (1/2018-2/2020), pandemic (3/2020-2/2022), and post-pandemic (3/2022-12/2024) periods. Setting: 37 North American hospitals Patients: Mechanically ventilated patients with persistent moderate-to-severe hypoxemia (PaO2/FiO2 ≤150 mmHg, FiO2 ≥0.6, and positive end-expiratory pressure ≥5 cmH2O). Intervention: Proning within 12 hours of meeting study hypoxemia criteria. Measurements and Main Results: Among 5,760 proning-eligible patients, 1,737 (30.2%) received proning: 8.0% pre-pandemic, 44.6% pandemic, and 19.9% post-pandemic. The adjusted odds ratio (OR) for proning during pandemic versus pre-pandemic periods was 8.25 (95% Confidence Interval (CI): 6.35-10.70) and pandemic versus post-pandemic, 2.76 (95% CI: 1.83-4.17). Proning varied widely by hospital and was quantified with the median odds ratio (median change in odds of proning an identical patient admitted at a lower versus higher proning hospital) of 2.54 (95% Credible Interval (CrI): 1.75-4.58) pre-pandemic, 2.33 (95% CrI: 1.92-3.04) pandemic, and 2.58 (95% CrI: 1.99-3.73) post-pandemic. Pandemic-period patients with SARS-CoV2 were proned more than those without (OR: 4.55, [95% CI: 3.85-5.56]), but pandemic-period patients without SARS-CoV2 were still proned more than pre-pandemic (OR: 3.87, [95% CI: 2.92-5.13]) or post-pandemic patients (OR: 1.37, [95% CI: 1.03-1.83]). Conclusions: In a North American cohort of proning-eligible patients, proning increased during the pandemic and then declined. Interventions that improve implementation of this life-saving treatment are urgently needed.