Prone position and reduced thoracoabdominal asynchrony in preterm newborns.

Objective: To assess the effect of prone and supine positions on breathing pattern variables, thoracoabdominal motion and peripheral oxygen saturation of hemoglobin of premature newborn infants recovering from respiratory distress syndrome, while breathing spontaneously and in rapid eye movement sleep.

Methods: This was a quasi-experimental study. Twelve preterms weighing > 1,000 g at enrollment were studied in both positions, in random order. Respiratory inductive plethysmography was used to analyze breathing pattern (tidal volume, respiratory rate, minute ventilation, mean inspiratory flow) and thoracoabdominal motion (labored breathing index, phase relation in inspiration, phase relation in expiration, phase relation in total breath and phase angle). Pulse oximetry was used to evaluate peripheral oxygen saturation. Student's t test for paired samples or the Wilcoxon test were used for statistical analysis. Significance was set at p < 0.05.

Results: A total of 9,167 respiratory cycles were analyzed. The prone position was associated with significant reductions in labored breathing index (-0.84+/-0.69; p = 0.001; 95%CI -1.29 to -0.40), phase relation in inspiration (-27.36+/-17.55; p = 0.000; 95%CI -38.51 to -16.20), phase relation in expiration (-32.36+/-16.20; p = 0.000; 95%CI -42.65 to -22.06) and phase relation in total breath (-30.20+/-14.76; p = 0.000; 95%CI -39.59 to -20.82). There were no significant differences between the two positions in any of the other variables analyzed.

Conclusion: The prone position resulted in a significant reduction in thoracoabdominal asynchrony, without affecting breathing pattern or peripheral oxygen saturation.