4A randomized trial of prolonged prone positioning in children with acute respiratory failure

Study objective: To compare the effect of the prone position (PP) vs supine position (SP) on oxygenation in children with acute respiratory failure (A RF). Design: Prospective, randomized controlled trial. Setting: A 36-bed pediatric critical-care unit in a tertiary-care, universi ty-based children's hospital. Patients: Ten children (mean [SD] age, 5 +/- 3.6 years) with ARF with a bas eline oxygenation index (OI) of 22 +/- 8.5. Interventions: Following a period of stabilization in the SP, baseline data were collected and patients were randomized to one of two groups in a two- crossover study design: group 1, supine/prone sequence; group 2, prone/supi ne sequence. Each position was maintained for 12 h, Lung mechanics and acut e response to inhaled nitric oxide were examined in each position. Measurements and main results: OI was significantly better in the PP compar ed to the SP over the 12-h period (analysis of valiance, p = 0.0016). When patients were prone, a significant improvement in OI was detected (7.9 +/- 5.3; p = 0.002); this improvement occurred early (within 2 h in 9 of 10 pat ients) and was sustained over the 12-h study period. Static respiratory sys tem compliance and resistance were not significantly affected by the positi on change. Inhaled nitric oxide had no effect on oxygenation in either posi tion. Urine output increased while prone, resulting in a significantly impr oved fluid balance (+ 6.6 +/- 15.2 mL/kg/12 h in PP vs + 18.9 +/- 13.6 mL/k g/12 h in SP; p = 0.041). No serious adverse effects were detected in the P P. Conclusion: In children with ARF, oxygenation is significantly superior in the PP than in the SP. This improvement occurs early, remains sustained for a 12-h period, and is independent of changes in lung mechanics.