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[Preprint]. 2025 Sep 5:2025.09.03.25334942.

doi: 10.1101/2025.09.03.25334942.

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

Anna K Barker¹, Akihiko Nishimura², Mark Nuppnau¹, Kevin G Buell³, Patrick G Lyons⁴, Wan-Ting Liao⁵, Brenna Park-Egan⁴, Benjamin E Schmid⁶, Nicholas E Ingraham⁷, Vaishvik Chaudhari⁸, Catherine A Gao⁵, Alexander C Ortiz^{6

9}, Gary E Weissman^{6

9}, Kaveri Chhikara³, Juan C Rojas⁸, Andre Ckb Amaral^{10

11}, William F Parker^{3

12}, Theodore J Iwashyna^{13

14}, David N Hager¹³, Michael W Sjoding¹, Chad H Hochberg¹³

Affiliations

¹ Division of Pulmonary and Critical Care, University of Michigan, Ann Arbor, MI, USA.
² Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
³ Department of Pulmonary and Critical Care, University of Chicago; Chicago, IL, USA.
⁴ Department of Medicine, Oregon Health & Science University, Portland, OR, USA.
⁵ Division of Pulmonary and Critical Care, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
⁶ Palliative and Advanced Illness Research Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
⁷ Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Minnesota Medical School, University of Minnesota, Minneapolis, MN, USA.
⁸ Division of Pulmonology, Critical Care, and Sleep Medicine, Rush University, Chicago, IL, USA.
⁹ Division of Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
¹⁰ Department of Critical Care Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
¹¹ Interdepartmental Division of Critical Care, University of Toronto, Toronto, Canada.
¹² Maclean Center of Ethics, University of Chicago, Chicago, IL, USA.
¹³ Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA.
¹⁴ Department of Health Policy and Management, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.

PMID: 40950483
PMCID: PMC12424874
DOI: 10.1101/2025.09.03.25334942

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

Anna K Barker et al. medRxiv. 2025.

[Preprint]. 2025 Sep 5:2025.09.03.25334942.

doi: 10.1101/2025.09.03.25334942.

Authors

Affiliations

¹ Division of Pulmonary and Critical Care, University of Michigan, Ann Arbor, MI, USA.
² Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
³ Department of Pulmonary and Critical Care, University of Chicago; Chicago, IL, USA.
⁴ Department of Medicine, Oregon Health & Science University, Portland, OR, USA.
⁵ Division of Pulmonary and Critical Care, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
⁶ Palliative and Advanced Illness Research Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
⁷ Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Minnesota Medical School, University of Minnesota, Minneapolis, MN, USA.
⁸ Division of Pulmonology, Critical Care, and Sleep Medicine, Rush University, Chicago, IL, USA.
⁹ Division of Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
¹⁰ Department of Critical Care Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
¹¹ Interdepartmental Division of Critical Care, University of Toronto, Toronto, Canada.
¹² Maclean Center of Ethics, University of Chicago, Chicago, IL, USA.
¹³ Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA.
¹⁴ Department of Health Policy and Management, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.

PMID: 40950483
PMCID: PMC12424874
DOI: 10.1101/2025.09.03.25334942

Abstract

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/F_iO₂ ≤150 mmHg, F_iO₂ ≥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.

Keywords: acute lung injury; evidence-based practice; hypoxemic respiratory failure; mechanical ventilators; prone position.

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Conflict of interest statement

AN received grants or contracts from the National Institutes of Health, United States Food and Drug Administration, and Alfred P. Sloan Foundation and has a leadership or fiduciary role in the International Society for Bayesian Analysis. PGL is an associate editor for Data Science, Critical Care Medicine. CAG received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from the Northwestern NUCATS Early Career Series, participates on the PRECISE trial data safety monitoring board or advisor board, and has a leadership or fiduciary role in American Thoracic Society Critical Care Early Career Professionals Working Group. ACO received travel support from the American Thoracic Society. GEW received grants or contracts from the National Institutes of Health, Advanced Research Projects Agency for Health, National Academy of Medicine, Gordon and Betty Moore Foundation, and John A. Hartford Foundation, lecture honoraria from the Institute for Healthcare Improvement and Worksafe BC, and has patents planned, issued, or pending with the American College of Physicians. WFP received grants or contracts from the National Institutes of Health and Greenwall Foundation. DNH received grants or contracts from Regeneron and the Centers for Disease Control and Prevention Influenza Vaccine Effectiveness Network and an institutional professional development stipend from Johns Hopkins University.

Figures

**Figure 1**
Proning rates across the CLIF Consortium. Variation in proning rates between 1/1/2018–12/31/2024, across nine health systems in the CLIF consortium

**Figure 2**
Proning rates by SARS-CoV2 status. Consortium-wide proning rates among patients with and without SARS-CoV2 between 1/1/2018–12/31/2024. Visualized rates reflect average proning rates over three-month periods, with the exception of post-pandemic data for patients positive for SARS-CoV2, which each reflect six months of data given the small number of these patients

**Figure 3:**
Risk-adjusted hospital-level variation in proning rates across CLIF Consortium. Variation in proning rates between 1/1/2018–12/31/2024, across 34 hospitals with at least 10 patients per period in the CLIF consortium. Hospitals are ranked by pandemic period proning use

See this image and copyright information in PMC

References

1. Bellani G, Laffey JG, Pham T, et al. : Epidemiology, Patterns of Care, and Mortality for Patients With Acute Respiratory Distress Syndrome in Intensive Care Units in 50 Countries. JAMA 2016; 315:788–800 - PubMed
1. Schmidt M, Pham T, Arcadipane A, et al. : Mechanical Ventilation Management during Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome. An International Multicenter Prospective Cohort. Am J Respir Crit Care Med 2019; 200:1002–1012 - PubMed
1. Guérin C, Beuret P, Constantin JM, et al. : A prospective international observational prevalence study on prone positioning of ARDS patients: the APRONET (ARDS Prone Position Network) study. Intensive Care Med 2018; 44:22–37 - PubMed
1. Duan EH, Adhikari NKJ, D’Aragon F, et al. : Management of Acute Respiratory Distress Syndrome and Refractory Hypoxemia. A Multicenter Observational Study. Ann Am Thorac Soc 2017; 14:1818–1826 - PubMed
1. Barker AK, Harlan EA, Kerlin MP, et al. : Attending Practice Variability Is a Key Component in Prone Positioning Initiation: A Retrospective Cohort Study. CHEST Crit Care 2025; 3:100158

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This is a preprint.

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

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

Authors

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Abstract

Conflict of interest statement

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References

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