Respiratory Parameters in Patients With COVID-19 After Using Noninvasive Ventilation in the Prone Position Outside the Intensive Care Unit

4 (17%) did not tolerate PP for more than 1 hour, 5 (21%) tolerated it for 1 to 3 hours, and 15 (63%) tolerated it for more than 3 hours.Characteristics of the patients and main results are displayed in the Table .The median time from admission to first PP was 1 day (interquartile range, 0-1.5 days).Neither sedation nor anxiolytics were used.Six patients were responders to PP, representing 25% (95% CI, 12%-45%) of the 24 patients included and representing 40% (6/15) (95% CI, 20%-64%) of the patients who sustained PP for 3 hours or more.Three patients were persistent responders.Among patients who sustained PP for 3 hours or more, PaO 2 increased from a mean of 73.6 (SD, 15.9) mm Hg before PP to 94.9 (SD, 28.3) mm Hg during PP (difference, 21.3 [95% CI, 6.3-36.3]mm Hg; P = .006)(Figure).No significant difference was found between PaO 2 before PP and PaO 2 after resupination (P = .53).None of the included patients experienced major complications.Back pain was reported by 10 patients (42%) during PP.At the end of a 10-day follow-up period, 5 patients required invasive mechanical ventilation.Four of them did not sustain PP for 1 hour or more and required intubation within 72 hours.Discussion | In this study of patients with COVID-19 and hypoxemic respiratory failure managed outside the ICU, 63% were able to tolerate PP for more than 3 hours.However, oxygenation increased during PP in only 25% and was not sustained in half of those after resupination.These results are consistent with findings from previous small studies of PP in nonintubated patients.5,6 A trial of PP may be a mechanism to select patients who will do well or it may be useful in a subset.The study had several limitations.The sample was small, a single episode of PP was evaluated, the follow-up was short, clinical outcomes were not assessed, and causality of the observed changes cannot be inferred.Further studies to identify optimal PP regimens and patients with COVID-19 in whom it may be beneficial are warranted.