Background & aims: Ambulatory pH testing often is used to guide the management of reflux symptoms that do not respond to proton pump inhibitor (PPI) therapy and to evaluate the contribution of acid reflux to atypical symptoms. Controversy exists as to whether such clinical studies are performed optimally off or on PPI therapy. The aim of the present study was to determine the feasibility of 4-day pH recordings using a pH system that would encompass time periods both before and during PPI therapy.
Methods: Eighteen patients underwent 4-day ambulatory pH testing using 2 separate receivers calibrated to a single Bravo pH capsule. Rabeprazole was administered on days 2-4 of the study (20 mg orally twice a day).
Results: Indications for pH testing were refractory heartburn, chest pain, or chronic cough. pH recordings showed that 9 patients (53%) had esophageal acid exposure values that exceeded 4% on day 1 and 7 patients (41%) had values that exceeded 5.3%. Patients showed significant and progressive reductions in acid exposure on days 2-4 of the recording period. Of the 7 patients with quantitatively abnormal levels of acid exposure on day 1, 86% had normalization by day 3.
Conclusions: Prolonged, esophageal pH recordings using the Bravo pH system are feasible and allow for combined testing both off and on a therapeutic trial of PPI. Such studies may allow for the acquisition of complementary information in a single test that may be useful in the management of patients with suspected gastroesophageal reflux disease symptoms.