Physiological Effect of Prone Positioning in Mechanically Ventilated SARS- CoV-2 Infected Patients with Severe ARDS: Preliminary Analysis of an Observational Study

Prone position ventilation has been shown to decrease mortality and improve oxygenation in ARDS patients. With best of our knowledge, no study reported physiological effect of prone position in SARS-CoV-2 infected ARDS patients. In this prospective observational study, data of n=20 consecutive laboratory confirmed SARS-CoV-2 patients with severe ARDS as per Berlin definition was included. Data of 20 patients analyzed with a median (Interquartile range, IQR) age of 56 (45.5-67) y and median (IQR) P/F ratio of 56 (54-66) with a median (IQR) PEEP of 12 (12-14) before initiation of prone position. Seventy-five percentage (95% CI 53.1-88.8) patients were prone responders at 16h prone session and 50 (95% CI 29.9-70.1) % patients were sustained responders. There was a significant decrease in plateau airway pressure (p<0.0001), peak airway pressure (p<0.0001) and driving pressure(p<0.0001) and increase in static compliance (p=0.001), P/F ratio (p<0.0001), PaO₂ (p=0.0002)and SpO₂ (p=0.0004) at 4h and 16h since initiation of prone session and also after return of supine position. Prone position in SARS-CoV-2 infected severe ARDS patients is associated with improvement in lung compliance and oxygenation in two-third of the patients and persisted in half of the patients.