Predictive Factors for Awake-Prone Manoeuvre Failure and Outcomes of Prone Positioning in Non-Intubated Patients with Acute Respiratory Failure Due to COVID-19

Abstract

Background: Prone positioning is an established evidence-based practice for acute respiratory distress syndrome (ARDS) patients undergoing invasive mechanical ventilation (IMV), but evidence is limited in non-ventilated, awake patients. This study investigated the predictors of successful awake prone positioning and the association with mortality.Methods: We prospectively studied 59 patients with COVID-19 and moderate ARDS admitted to the ICU for a high-flow nasal cannula (HFNC), non-invasive mechanical ventilation (NIV), a reservoir mask or a nasal cannula who underwent awake prone manoeuvres from 1 March 2020 to 30 August 2020. Age, sex, comorbidities, Simplified Acute Physiology Score 3 (SAPS 3), and body mass index (BMI) were recorded at admission. Multivariate Poisson regression was used to control for confounders.Findings: Fifty-nine patients (54.1±12.9 years) were enrolled. The mean BMI was 31.3±7.0. Thirty-two (54.2%) patients used reservoir masks, 21 (35.6%) used HFNCs, 3 (5.1%) received NIV, 3 (5.1%) used a nasal cannula during awake prone ventilation, and 26 (44.1%) needed IMV. The successful group had a higher survival rate (87.9%) than the failure group (38.5%). Additionally, 30 (90.9%) and 12 (46.2%) patients in the successful and failure groups, respectively, were discharged from the ICU, with 25 (75.8%) and 13 (50%) discharged after 28 days. The successful group had shorter ICU (4.5 (3-8.8) days) and hospital (11 (7.3-16.8) days) stays. Pre-manoeuvre partial oxygen saturation (SpO2) (p = 0.013) was associated with increased mortality.Interpretation: Manoeuvre failure was associated with pre-manoeuvre SpO2. Responders had better survival and shorter durations of IMV, ICU stays and hospitalization.Funding: No fundingDeclaration of Interests: The authors have no conflicts of interest to declare.Ethics Approval Statement: This study received Ethics Committee approval (CAAE 61274316.1.0000.5327).