Day-to-day variability in acid reflux patterns using the BRAVO pH monitoring system

Background & Goals: The wireless pH monitoring system such as the BRAVO pH system is a significant advancement in the evaluation of patients with gastroesophageal reflux because of its potentially better tolerability and the ability to record data over a 48-hour period. The aim of our study was to evaluate safety, performance, tolerability, and day-to-day variability in acid reflux patterns using the BRAVO pH system. Methods: A total of 90 consecutive patients (48 men and 42 women) with persistent reflux symptoms underwent BRAVO pH capsule placement from October 2002 to August 2003 at a tertiary care hospital. The BRAVO pH capsule was deployed 6 cm proximal to the squamocolumnar junction under endoscopic guidance. The pH recordings over 48 hours were obtained after uploading data to a computer from the pager-like device that recorded pH signals from the BRAVO pH capsule. Results: Successful pH data over 48 hours was obtained in 90% of patients. Nearly two thirds of patients experienced a variety of symptoms ranging from a foreign body sensation to chest discomfort or pain. Four patients had severe chest pain, 3 of whom required endoscopic removal of the BRAVO pH capsule. In 74.4% of patients, number of reflux events as well as time (%) pH < 4 correlated from the first 24-hour period to the second 24-hour period. However, in 28% of patients, no predictable pattern of (%) time pH < 4 in the supine position was reproduced from one 24-hour period to the next 24-hour period. Conclusions: The BRAVO pH system appears a safe and effective method of recording esophageal acid exposure. It is an acceptable alternative for patients who are unwilling or unable to tolerate nasopharyngeal catheter-based pH studies, and it has a potential advantage of the 2-day recording period.