Optimal timing for awake prone positioning in Covid-19 patients: Insights from an observational study from two centers

Abstract

BackgroundThe widespread application and interest in awake prone positioning stems from its ease and availability and its ability to enhance patients' oxygenation. Nevertheless, due to the absence of consensus over the regimen of awake prone positioning, the efficacy of awake prone positioning remains uncertain. ObjectiveTo explore the optimal regimen for awake prone positioning, including the timing of initiation, ideal daily duration, and strategies for improving patient comfort and encouraging adherence. DesignRetrospective observational study. Setting(s)Two university-affiliated hospitals in Shanghai. ParticipantsBetween December 2022 and February 2023, a total of 475 patients with COVID-19-related pneumonia who received awake prone positioning were observed. MethodsThe data were collected from the hospital's electronic medical record system. The differentiation efficiency of peripheral blood oxygen saturation [SpO2]:fractional oxygen concentration in inspired air [FiO2] ratio at first awake prone positioning for different outcomes was tested by the area under the receiver operating characteristic curve. The Cox proportional hazard regression model was used to analyze the relationship between time to occurrence of 28-day outcomes and collected variables. Kaplan–Meier curves were plotted with the percentage of 28-day outcomes according to the SpO2:FiO2 ratio at first awake prone positioning after controlling covariates through Cox regression. ResultsThe best efficiency in predicting patient outcomes was achieved when the cutoff SpO2:FiO2 ratio at first awake prone positioning was 200. Patients with a reduced SpO2:FiO2 ratio (≤200) experienced more adverse respiratory outcomes (RR = 5.42, 95%CI [3.35, 8.76], p < 0·001) and higher mortality (RR = 16.64, 95%CI [5.53, 50.13], p < 0.001). Patients with a SpO2:FiO2 ratio of ≥200 at first awake prone positioning, longer duration between first awake prone positioning and admission, more awake prone positioning days, and better awake prone positioning completion were significantly protected from 28-day adverse respiratory outcomes and mortality. ConclusionsInitiating awake prone positioning with a SpO2:FiO2 ratio exceeding 200, increasing the number of awake prone positioning days, prolonging the time between first awake prone positioning and admission, and achieving better completion of awake prone positioning were found to be significantly associated with reduced adverse respiratory outcomes and mortality. RegistrationClinicalTrials.gov; No.: NCT05795751; URL: www.clinicaltrials.gov.