Supplement Abstracts Submitted for the 70th Annual Scientific Meeting of the American College of Gastroenterology: ESOPHAGUS
Purpose: Esophageal 24-hr pH-metry is a useful test for the diagnosis of gastroesophageal reflux disease. Recent advances have resulted in the approval of the BRAVO capsule pH-metry. The BRAVO is a radiotelemetry, catheter-free pH system that provides prolonged, 48-hr assessment of esophageal pH. The capsule is most often placed during EGD with the patient is sedated, which may lead to increased variability between recording day 1 and recording day 2. We have developed a method for placing the capsule orally in unsedated patients.
Aim: The aim of this study was to determine the concordance of data between the first and second 24-hr recording periods in sedated vs unsedated patients using Bravo.
Methods: Consecutive patients (n = 87; 42 UnSed [24F & 18M], 45 Sed [25F & 20M]) were studied over two continuous 24-hr freely ambulating periods. All patients were studied following an overnight fast, but were encouraged to follow their standard diet and activities during the study. The concordance between the two 24-hr periods was evaluated in Sed vs Unsed patients using Pearson Correlation Coefficients. Between group differences in pH-metry parameters were evaluated controlling for acid medication use via Multivariate ANOVA with significance set at the p < 0.05 level.
Results: No differences were noted between groups for age or gender. The BRAVO capsule detached from the mucosa prior to study completion in 2 Sed and no Unsed patients. These were not included in the statistical analyses. Overall, no significant group or group x days effects were found. Significant correlations were identified between the two 24-hr recording periods for both the Sed and Unsed groups. However, variability was higher and correlations lower in the Sed group compared to the Unsed group.
Conclusions: The Bravo pH monitoring system proved to be a safe and well-tolerated technique for measuring esophageal acid exposure for prolonged periods in unrestricted patients. No significant differences were found between sedated, endoscopic placement and unsedated placement of the BRAVO capsule. However, less variability and higher reproducibility was noted between the two measurement days following unsedated capsule placement.