The effect of body positioning on gastroesophageal reflux in premature infants: evaluation by combined impedance and pH monitoring.

OBJECTIVE: To evaluate the pattern of acid and nonacid gastroesophageal reflux (GER) in different body positions in preterm infants with reflux symptoms by a combined multichannel intraluminal impedance (MII)-pH monitoring, which identifies both acid and nonacid GER. STUDY DESIGN: Premature infants with frequent regurgitation and postprandial desaturation (n = 22) underwent a 24-hour recording of MII-pH. In a within-subjects design, reflux indexes were analyzed with the infants in 4 different positions: supine (S), prone (P), on the right side (RS), and on the left side (LS). RESULTS: All infants were analyzed for 20 hours. The mean number of recorded GER episodes was 109.7. The mean esophageal exposure to acid and nonacid GER was lower in positions P (4.4% and 0.3%, respectively) and LS (7.5% and 0.7%, respectively) than in positions RS (21.4% and 1.2%, respectively) and S (17.6% and 1.3%, respectively). The number of postprandial nonacid GER episodes decreased but the number of acid GER episodes increased over time. The LS position showed the lowest esophageal acid exposure (0.8%) in the early postprandial period, and the P position showed the lowest esophageal acid exposure (5.1%) in the late postprandial period. CONCLUSION: Placing premature infants in the prone or left lateral position in the postprandial period is a simple intervention to limit GER.