Pediatrics · Medical Literature
Prone Positioning in Viral Bronchiolitis—Back to the Back?
Abstract
Acute viral bronchiolitis is the most common diagnosis in US children’s hospitals, and respiratory failure is the costliest diagnosis across all pediatric acute care. Despite the prevalence of this condition and its impact on children, families, and health systems, evidence-based treatments for acute bronchiolitis in hospitalized children are few and guidelines largely recommend against most interventions. In this issue of JAMA, Baudin and colleagues for the PROPOSITIS Investigators evaluated a promising but understudied option: prone positioning. In a well-designed randomized clinical trial (RCT) conducted from 2021 to 2023, the authors enrolled 451 infants younger than 6 months with viral bronchiolitis who were receiving high-flow nasal cannula (HFNC) support. The primary end point of the study was escalation of care to noninvasive or invasive positive pressure ventilation (notably, only 3 children in the cohort were intubated). The primary intention-to-treat analysis did not reach statistical significance—with an odds ratio for escalation with prone positioning of 0.66 (95% CI, 0.40-1.07)—which was surprising given that their pilot physiological study suggested that prone positioning either improves effort of breathing or has negligible impact.
Clinical relevance
Acute viral bronchiolitis is the most common inpatient diagnosis in US children's hospitals, yet evidence-based therapies remain scarce and guidelines discourage most interventions. This RCT directly addresses a critical management gap by rigorously evaluating prone positioning—a low-cost, low-risk intervention—in infants on high-flow nasal cannula (HFNC), a population at meaningful risk for respiratory failure. Clinicians caring for hospitalized infants with bronchiolitis need this evidence to make informed decisions about positional adjuncts to respiratory support.
Key findings
1. Study population: 451 infants younger than 6 months with viral bronchiolitis receiving HFNC support were enrolled in this multicenter RCT conducted from 2021 to 2023. 2. Primary outcome: Escalation of care to noninvasive or invasive positive pressure ventilation was the primary endpoint; only 3 children in the entire cohort ultimately required intubation. 3. Primary intention-to-treat result: Prone positioning did not significantly reduce escalation of care (OR 0.66, 95% CI 0.40–1.07), failing to reach statistical significance. 4. Direction of effect: Despite non-significance, the OR of 0.66 suggests a potential 34% relative reduction in escalation odds with prone positioning, indicating a clinically meaningful trend that the study may have been underpowered to confirm. 5. Prior physiological signal: A preceding pilot study suggested prone positioning either improves work of breathing or has negligible impact, providing biological plausibility for the intervention but highlighting a discordance between physiological and clinical endpoints. 6. Intervention context: Prone positioning was evaluated as an adjunct to HFNC, situating findings specifically within the subpopulation of infants already requiring escalated respiratory support rather than those on standard low-flow oxygen.
Practice implications
Prone positioning cannot be routinely recommended as a standard-of-care intervention for HFNC-supported infants with bronchiolitis based on this trial, as the primary intention-to-treat analysis did not achieve statistical significance. However, given the favorable direction of effect (OR 0.66), the low cost, and the absence of significant harms signaled in the pilot data, clinicians may reasonably consider supervised prone positioning as a low-risk adjunct in infants with bronchiolitis on HFNC who are not improving, while awaiting further adequately powered trials. Patient selection should focus on infants under 6 months on HFNC, with vigilant continuous monitoring given the known risk of positional airway compromise in this age group.