Placement of the Bravo wireless pH monitoring capsule onto the gastric wall under endoscopic guidance

Background: The Bravo system was designed mainly to monitor esophageal pH, and there have been no reports on gastric pH monitoring using this system. Objective: To place the Bravo capsule on the gastric wall and monitor gastric pH. Design: Experimental clinical trial with the cooperation of volunteers. Setting: Academic medical center. Patients: Eleven volunteers (9 men, 2 women; mean age 38 years; 3 had symptoms of GERD). Interventions: The Bravo system was introduced into the esophagus and stomach along a thin endoscope and capsules were attached one each to the esophageal and gastric walls under direct vision through the endoscope. Esophageal and gastric pHs were simultaneously monitored. Results: The 2 capsules were successfully placed in 10 of the 11 subjects, and both esophageal and gastric pHs I were monitored for 48 hours in 9 subjects. Mild to moderate precordial pain was observed in 7 subjects, but no other complications or side effects were observed in this study. The gastric pH of 10 subjects increased after I meals and returned to baseline pH 2 hours later. Decrease of esophageal pH was observed I hour after a meal in the symptomatic subjects and corresponded to the time when gastric pH decreased secondary to the increase of pH with meals. Conclusions: The Bravo capsule is easily placed on the gastric wall under endoscopic assistance and enables long ambulatory monitoring of gastric pH.