Effect of serial awake prone positioning on oxygenation in patients admitted to intensive care with COVID-19

Introduction Awake prone positioning (APP) might benefit patients with COVID-19 by improving oxygenation, but it is unknown whether this improvement can be sustained with serial proning episodes. Methods We conducted a retrospective review of adults with COVID-19 admitted to one intensive care unit, in those who underwent APP and controls. Patients in both groups had type 1 respiratory failure requiring oxygen (but not initially intubated), confirmed SARS-CoV-2 PCR by nasopharyngeal swab and findings of multifocal ground-glass opacities on imaging. For the APP group, serial SpO(2)/FiO(2) measurements were recorded after each proning episode. Results Of 77 patients admitted, 50 (65%) were excluded because they had already been intubated. Another 7 (9%) had undergone APP prior to admission. Of the remaining 20, 10 underwent APP and 10 were controls. Patients in both groups had similar demographics, subsequent intubation and survival. Of those who underwent APP, SpO(2)/FiO(2) was most likely to increase after the first episode (before median: 152, IQR 135-185; after: median 192, IQR 156-234, p=0.04). Half of participants (5) in the APP group were unable to tolerate more than two APP episodes. Conclusions Most patients with COVID-19 admitted to the intensive care are not suitable for APP. Of those who are, many cannot tolerate more than two episodes. Improvements in SpO(2)/FiO(2) secondary to APP are transient and most likely in the first episode. Our findings may explain why other studies have failed to show improvements in mortality from APP despite improvements in oxygenation.