Esophageal pH Monitoring Using a Wireless System

Abstract

Purpose: Traditional catheter-based esophageal pH testing is limited by patient discomfort and inconvenience. A catheter-free pH monitoring system has become available. The aim of this study was to report our experience with this wireless pH-monitoring device over a 48 hr period in patients with typical and extraesophageal manifestations of GERD. Methods: Medical records of consecutive patients undergoing wireless pH monitoring at our institution were reviewed. Results: 90 patients (58 F/32 M, mean age 50) underwent wireless pH monitoring between 7/2003 and 6/2005. Indications for the study were typical reflux symptoms which included; heartburn and regurgitation (31%), and atypical symptoms which included non cardiac chest pain (NCCP) (28%); pulmonary symptoms (chronic cough, asthma) (16%); ENT symptoms (laryngitis, hoarseness, globus, and abnormal throat sensations (25%). Incomplete measurements were obtained in three (3%) of these patients due to poor probe attachment or inadequate data retrieval from the recorder secondary to device or computer malfunction. One patient did require a repeat endoscopy for chest pain, and the capsule was knocked off into the stomach with subsequent relief. Adequate diagnostic data were obtained in the remaining 87 patients (95%). In the typical reflux symptom group 52% had positive studies (defined as an average pH < 4 during the 48hr period); however 14% of the positive studies were while on proton pump inhibitor therapy (PPI). In the atypical symptoms group, the results were as follows for positive studies: NCCP 12% (33% on PPI's), pulmonary symptoms 21% (33% on PPI's), ENT symptoms 18% (all off PPI's). Conclusions: (1) Many patients with ENT symptomatology were referred after positive FEEST evaluations; however, only 18% (4/22) of this group had a positive wireless pH study (off PPI's). In the NCCP patients, only 12% (3/24) had positive pH studies for GERD, and 21% (3/14) were positive in the pulmonary group. This implies either lack of abnormal acid reflux or appropriate acid suppression for those patients on PPI's with extraesophageal symptoms. (2) We question whether this atypical group of GERD patients (ENT, pulmonary, and NCCP) require chronic, long-term high-dose PPI's as our limited data does not support this practice. Further larger controlled/randomized trials are needed to study this patient population and wireless pH testing can be considered an appropriate modality of testing to accomplish this.