Background: Protocolized prone positioning has been shown to decrease mortality in patients with severe ARDS requiring mechanical ventilation [2]. Patients with COVID-19 can develop severe hypoxemic respiratory failure, with recent physiologic and autopsy studies showing similar pathophysiology to ARDS [3,4].

Methods: Single-center prospective before-after study of prone positioning in nonintubated, spontaneously breathing patients with hypoxemic respiratory failure due to COVID-19. To be eligible, patients must have a chest CT showing posterior infiltrates, and normal mental status.

Results: Twenty-four patients were enrolled, out of 88 screened (28%). Prone positioning was relatively well tolerated, with 63% of patients tolerating ≥ 3 hours, and an additional 21% tolerating 1-3 hours. The primary endpoint was increase in PaO2 ≥20%, which was achieved in 6 patients (25%), and there were no major complications.

Limitations: Single center, no randomization, arbitrary definition of “response” to proning, and minimal reporting of clinically meaningful or patient-centered outcomes, such as need for mechanical ventilation or hospital length of stay.

Conclusions: This in an interesting proof-of-concept study, showing that voluntary prone positioning in spontaneously breathing patients is safe, reasonable well tolerated, and associated with short-term improvement in PaO2 in a subset of carefully selected patients. The lack of randomization does not allow for inference of causality, and short-term improvement in PaO2 is not necessarily a clinically meaningful outcome, but this study certainly provides rationale for further randomized studies, several of which are planned.

References:

1. Elharrar X, Trigui Y, Dols A, et al. Use of Prone Positioning in Nonintubated Patients With COVID-19 and Hypoxemic Acute Respiratory Failure. JAMA. Published online May 15, 2020. doi:10.1001/jama.2020.8255
2. Guérin C, Reignier J, Richard J-C, et al. PROSEVA Study Group. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med. 2013; 368(23):2159-2168. doi:10.1056/NEJMoa1214103.
3. Schaller T, Hirschbühl K, Burkhardt K et al. Postmortem Examination of Patients With COVID-19. JAMA. Published online May 21, 2020. doi:10.1001/jama.2020.8907
4. Ziehr DR, Alladina J, Petri CR et al. Respiratory Pathophysiology of Mechanically Ventilated Patients with COVID-19: A Cohort Study [published online ahead of print, 2020 Apr 29]. Am J Respir Crit Care Med. 2020;10.1164/rccm.202004-1163LE. doi:10.1164/rccm.202004-1163LE

The Department of Medicine COVID-19 Journal Club is dedicated to understand and applying data on COVID-19 to inform prevention and management efforts for healthcare workers and patients.

This article by Stephen Halliday, MD MSCI, assistant professor, Allergy, Pulmonary, and Critical Care Medicine. Reviewed by Nasia Safdar, MD, PhD, professor, Infectious Disease, and vice chair for research, Department of Medicine.

Banner image: Centers for Disease Control and Prevention image library