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.

Abbreviations: BEI, Bolus exposure index, GER, Gastroesophageal reflux, LES, Lower esophageal sphincter, LS, Left side, MACT, Mean acidic clearing time, MII, Multichannel intraluminal impedance, P, Prone, RIpH, Reflux index, RS, Right side, S, Supine, TLESR, Transient lower esophageal sphincter relaxation