title: Oesophageal pH monitoring using the Bravo catheter-free radio capsule.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Upper Gastrointestinal Surgery, Royal Berkshire Hospital, Reading, UK. rgillies@doctors.org.uk
authors.forename: Richard S
authors.initials: RS
authors.lastname: Gillies
authors.forename: Jane M
authors.initials: JM
authors.lastname: Stratford
authors.forename: Michael I
authors.initials: MI
authors.lastname: Booth
authors.forename: Thomas C B
authors.initials: TC
authors.lastname: Dehn
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D000368:Aged; D050782:Esophageal pH Monitoring / Q000009:adverse effects / Q000295:instrumentation*; D004945:Esophagoscopy; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D010146:Pain / Q000209:etiology; D013686:Telemetry / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods