Impact of prone position on outcomes of COVID-19 patients with spontaneous breathing

Background: In this study, we explored whether early application of the prone position (PP) can improve severe hypoxemia and respiratory failure in coronavirus disease 2019 (COVID-19) patients with spontaneous breathing. Methods: This is a prospective observational study of severe, critically ill adult COVID-19 patients admitted to the intensive care unit. All vital parameters were recorded in real time for all patients. Moreover, the results of chest computed tomography (CT), when available, were analyzed. Results: PP was applied in 21 patients who were breathing spontaneously. The application of PP was associated with a significant increase in oxygen saturation measured by pulse oximetry (SpO(2)) from 82%+/- 12% to 96%+/- 3% (P<0.001) 1 hour later. Moreover, PP was associated with a significant reduction in respiratory rate from 31 +/- 10 to 21 +/- 4 breaths/min (P<0.001). Furthermore, the number of patients who exhibited signs of respiratory distress after PP was reduced from 10 (47%) to 3 (14%) (P=0.04). Early PP application also led to a clear improvement on CT imaging. It was not, however, associated with a reduction in mortality rate or in the use of invasive mechanical ventilation (P>0.05 for both). Conclusions: Our study confirmed that the early application of PP can improve hypoxemia and tachypnea in COVID-19 patients with spontaneous breathing. Randomized controlled trials are needed to confirm the beneficial effects of PP in COVID-19 patients with spontaneous breathing.