Body position and esophageal sphincter pressure in infants

Area of Science:

• Pediatric Gastroenterology
• Infant Physiology

Background:

• Gastroesophageal reflux (GER) is common in infants.
• Postural therapy is often used to manage infant GER.
• The mechanism by which position affects GER is not fully understood.

Purpose of the Study:

• To investigate the effect of infant positioning on lower esophageal sphincter (LES) pressure.
• To compare LES pressure in infants with and without GER.
• To evaluate the diagnostic utility of different methods for identifying infant GER.

Main Methods:

• Lower esophageal sphincter pressure was measured in infants in supine, prone, right lateral, left lateral, and upright positions.
• Infants were categorized into groups with and without GER.
• One- and 24-hour pH probe tests, upper gastrointestinal roentgenograms, and esophageal manometry were compared for diagnostic accuracy.

Main Results:

• Infant position had no significant effect on LES pressure in either group.
• Infants with GER demonstrated significantly lower LES pressure across all positions compared to those without GER.
• One- and 24-hour pH probe tests were superior in identifying reflux in symptomatic infants compared to imaging or manometry.

Conclusions:

• The efficacy of postural therapy for infant GER is unlikely to be mediated by changes in LES pressure.
• Gravity's effect on the gastric pool is a more probable factor influencing GER in different positions.
• Ambulatory esophageal pH monitoring is the most effective diagnostic tool for symptomatic infant GER.