Does the Bravo™ pH capsule affect esophageal motor function?

The aim of this study was to determine whether attachment of the Bravo™ pH monitoring capsule alters esophageal motility. Twenty normal subjects were studied with 36-channel high-resolution manometry before and after Bravo™ capsule placement. Subjects performed 10 5-mL water-swallows in both upright and supine positions and two 5-mL barium-swallows under fluoroscopy synchronized with manometry recordings. There was no significant change in basal esophagogastric junction (EGJ) pressure, EGJ relaxation pressure or peristaltic function before and after Bravo™ placement in either position. However, a 2-cm focus of augmented peristalsis was found corresponding to the position of the Bravo™ capsule. Ten subjects were aware of the capsule (7 had a mild foreign body sensation, 1 had mild discomfort, and 2 had chest pain altering daily activity or diet) while nine subjects were unaware of the capsule. Subjects who were aware of the capsule's presence exhibited a greater augmentation of peristalsis than those who were not (P < 0.05). Neither EGJ function nor peristaltic performance were significantly altered by the presence of a Bravo™ capsule. However, capsule presence was associated with a locus of augmented peristalsis and this phenomenon was most evident in subjects who perceived the presence of the Bravo™ capsule.