Impact of awake prone positioning duration on intubation or mortality in COVID-19 patients with acute respiratory failure: secondary analysis of a randomized clinical trial.

Publication date: Jun 23, 2025

Compared with shorter awake prone positioning (APP), prolonged APP (≥ 12 h daily) reduces the intubation rate in patients with COVID-19-related acute hypoxemic respiratory failure (AHRF). However, the optimal APP duration is uncertain. In this secondary analysis, we aimed to explore whether a longer APP duration is associated with improved outcomes and to identify the optimal duration of APP. Data from a multicenter randomized controlled trial involving nonintubated COVID-19 patients with AHRF were analyzed. Daily APP duration over 7 days after randomization was recorded as the primary exposure in present study. The primary outcome was the time from randomization to APP failure, which was defined as a composite of tracheal intubation or mortality within 28 days. A Cox proportional hazards regression model was employed to elucidate the associations, and the daily duration of APP was treated as time dependent. A total of 409 patients were randomized in the original trial, and 408 were enrolled in this analysis. Among these patients, 105 (25. 7%) experienced APP failure. A longer daily APP duration was associated with a lower risk of APP failure, with a hazard ratio (HR) of 0. 93 (95% confidence interval (CI): 0. 88-0. 98), and the association was significant only during the first three days after randomization. There was a nonlinear relationship between the daily APP duration and the risk of APP failure (P = 0. 015 for nonlinearity). Compared with patients whose APP duration ranged from 8 to 12 h per day, patients with less than 8 h of APP per day had a greater risk of APP failure (HR 2. 44, 95% CI 1. 21-4. 92), whereas extending APP beyond 12 h per day did not improve the outcomes further (HR 1. 03, 95% CI 0. 51-2. 10, P = 0. 932). A longer daily APP duration was associated with a reduced risk of APP failure in COVID-19-related AHRF patients, and the optimal APP duration was 8-12 h per day. Clinical trial ClinicalTrials. gov: NCT05677984, Registered January 3, 2023. https://register. gov/prs/app/action/SelectProtocol?sid=S000CST9&selectaction=Edit&uid=U0000YKY&ts=4&cx=-x0muek.

Semantics

Original Article