Oesophageal pH monitoring using the Bravo catheter-free radio capsule

Abstract

Oesophageal pH monitoring is the current standard for the diagnosis of gastro-oesophageal reflux disease. The Bravo capsule allows 48-h monitoring without the need for a naso-oesophageal catheter. Our aim was to assess the Bravo capsule in terms of patient discomfort and interference with daily activities, and to determine if 48-h Bravo pH studies facilitate the diagnosis of gastro-oesophageal reflux disease. Ambulatory pH studies were performed at two hospitals using either the Bravo capsule (n=100) or a conventional naso-oesophageal catheter (n=100). Participants were selected either for investigation of symptoms suggestive of gastro-oesophageal reflux disease, or to follow-up antireflux surgery. All participants completed questionnaires to assess discomfort and interference with daily activities. Eighty-nine Bravo studies recorded at least 48 h of data, and 95 were diagnostic. Bravo participants reported significantly less discomfort during insertion (P<0.0001) and monitoring (P<0.0001), and less interference with daily activities (P<0.0001), eating (P<0.005), sleeping (P<0.0001) and work (P<0.0001). No significant difference was observed between day 1 and 2 median total time pH<4 (4.0 and 4.3%, P=0.64), erect time pH<4 (5.0 and 5.0%, P=0.56), supine time pH<4 (0.5 and 0.5%, P=0.23), and Johnson-DeMeester scores (15.9 and 16.2, P=0.90). Ten Bravo participants (10%) were diagnosed with gastro-oesophageal reflux disease using day 2 data after a normal day 1. The Bravo capsule significantly reduces the patient discomfort and interference with normal daily activities during pH monitoring associated with a naso-oesophageal catheter. Moreover, 48-h Bravo studies offer an advantage over conventional 24-h studies in diagnosing gastro-oesophageal reflux disease.