Role of Attending Practice Variability in Prone Positioning Initiation

Abstract

Background

Prone positioning is underused, despite mortality benefits. Prior studies highlight that patient-independent factors may influence prone positioning rates, but attending-specific contributions are unknown.

Research Question

Does significant variability in prone positioning rates exist among attending physicians?

Study Design and Methods

This is a retrospective cohort study of 514 adults receiving mechanical ventilation in a tertiary-care medical or surgical ICU from January 1, 2015, through June 30, 2024. Inclusion criteria included Pao₂ to Fio₂ ratio of ≤ 150 with Fio₂ of ≥ 60% and positive end-expiratory pressure of ≥ 5 cm H₂O within 0 to 36 hours and 36 to 72 hours of intubation. The primary outcome was prone positioning within 72 hours of intubation or 24 hours of meeting prone positioning criteria. We hypothesized that attending variability was a significant predictor of prone positioning. We fit a mixed-effects logistic regression model to evaluate attending-level variability in prone positioning use, adjusting for 6 potential patient-centered prone positioning barriers and facilitators (age, BMI, COVID-19 status, code status, Pao₂ to Fio₂ ratio, and vasopressor use) and ICU location (medical or surgical).

Results

Among 514 patients eligible for prone positioning, 87 patients (17%) underwent prone positioning. Significant attending-level variability in prone positioning was noted among the 48 attendings included in the analysis, with risk- and reliability-adjusted rates ranging from 14.9% to 74.2% and a median OR among attending physicians of 2.6 (95% CI, 1.7-5.2). This effect size was associated more strongly with prone positioning than a 30-mm Hg decrease in Pao₂ to Fio₂ ratio. Even among patients with clinical documentation of ARDS on the day of prone positioning eligibility, the median OR among attending physicians was 2.4 (95% CI, 1.5-7.3). Additional patient factors predicting prone positioning included COVID-19 status, code status, and Pao₂ to Fio₂ ratio.

Interpretation

Our results show that large variation in prone positioning practices exists among attending providers, and future work should consider attending-focused and system-wide interventions as potential novel targets to improve prone positioning rates.