The Effect of Body Position on Oxygenation, Ventilation, and Diaphragmatic Workload in Infants Born Premature on Noninvasive Neurally Adjusted Ventilatory Assist

Objective: To determine the effect of supine vs prone body position on oxygenation, ventilation, and diaphragmatic workload in infants born ≤32 weeks of gestation on noninvasive neurally adjusted ventilatory assist (NAVA). Methods: This study was conducted in 2 level III-IV neonatal intensive care units. Infants were randomly assigned into 1 of 2 starting positions: supine or prone. Infants alternated between supine and prone positioning every 3 hours, for a total of 12 hours. Nursing care and feeding were done every 3 hours with position changes. Infants were allowed a period of 1 hour after nursing care before data collection resumed. Results: Thirty subjects (22-32 weeks of gestation at birth) were included in the study. Edi peaks were lower in prone positioning; 8.61 ± 5.57 vs 9.79 ± 6.14 μV (P = .02). Edi minutes were similarly lower in the prone position; 2.76 vs 3.05 μV (P = .04). Peak airway pressure, heart rate, respiratory rate, oxygen saturation, transcutaneous carbon dioxide level, and oxygen requirements were not affected by position. When stratified by gestational age, Edi peaks remained lower in prone vs supine positioning; 8.60 ± 5.14 vs 10.14 ± 5.54 μV (P = .009). The number of clinically significant events were similar between both groups. Conclusion: Prone positioning is associated with lower diaphragmatic workload in infants born premature on noninvasive NAVA. Despite this, infants had comparable clinical parameters in both prone and supine positions, suggesting that nivNAVA is able to eliminate differences related to body position to provide consistent proportional and synchronized respiratory support.