Extended Prone Positioning in ARDS: A Systematic Review and Meta-Analysis

Background: Prone positioning is a recommended therapy for patients with moderate-to-severe ARDS; however, the optimal duration of this maneuver is still unknown. Methods: We performed a systematic review and meta-analysis comparing clinical outcomes of extended (≥24 h) versus traditional prone positioning (16–24 h) of adults with moderate-to-severe ARDS receiving invasive mechanical ventilation. Results: Ten studies involving 2,412 subjects met the inclusion criteria, including one randomized controlled trial and 9 observational studies, all with COVID-19-related ARDS. Extended prone positioning was associated with reduced mortality compared with the traditional approach (risk ratio [RR]: 0.76, 95% CI 0.66–0.86, I 2 = 12.8%). Sensitivity and subgroup analyses confirmed consistency across risk of bias, baseline P aO 2 /F iO 2 , and PEEP levels. No differences were found in duration of mechanical ventilation (mean difference [MD]: 2.43 days, 95% CI −1.06 to 5.92, I 2 = 70%) or ICU stay (MD: 1.31 days, 95% CI −1.07 to 3.68, I 2 = 55%). The extended strategy was associated with a higher incidence of pressure injuries (RR: 1.30, 95% CI 1.02–1.65, I 2 = 56%) but no differences in device displacement or hemodynamic instability. Certainty of evidence was rated as low to very low. Conclusions: Extended prone positioning was associated with reduced mortality in ARDS but increased risk of pressure injuries, without impact on ventilator duration or ICU stay. While this strategy appears feasible and potentially beneficial, further randomized trials are warranted to confirm its role in routine practice. Trial registration: PROSPERO no. CRD42024529311.