An Assessment of pH Testing Methods

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01364610
Recruitment Status : Completed
First Posted : June 2, 2011
Last Update Posted : June 22, 2015
Information provided by (Responsible Party):
Christopher Andrews, University of Calgary

Brief Summary:

Gastroesophageal reflux disease (GERD) is a common and potentially debilitating disorder. Typical symptoms include heartburn and regurgitation of acid tasting substances. GERD is a chronic disease and in some cases, more alarming symptoms including food sticking in the esophagus, pain with swallowing, bleeding, anemia and weight loss develop.

In Alberta, upper endoscopy is the first line of investigation accompanied by an ambulatory 24-hour esophageal pH monitoring for patients with symptoms that are unresponsive to acid-suppressing therapy or who exhibit alarm symptoms.

Current standard of care in Alberta for esophageal pH monitoring first requires an esophageal manometry test to identify the location of the lower esophageal sphincter followed by the placement of a thin catheter with one or more pH probes inserted through the nose and taped in place to the face for 20 -24 hours. The patient wears a small battery powered data logger and maintains a diary of GERD symptoms and activity. This system enables the recording and correlation of specific symptoms with reflux episodes over extended periods and provides direct evidence of GERD. The nasally passed pH catheter is uncomfortable and restrictive for some patients often resulting in abnormal eating, drinking, activity and sleeping patterns. The data collected may not be representative of the patient's typical experience and may not reflect the true severity of the disease.

A wireless diagnostic pH monitoring system called Bravo pH Monitoring System developed by Medtronic is approved for use in Canada and is commercially available. This system eliminates the need for a catheter by utilizing a capsule the size of a gel-cap and radio frequency technology to monitor esophageal pH. It has been shown to be safe and as sensitive as conventional catheter-based pH probe monitoring. The Bravo system can be sited either endoscopically or manometrically.

The goal of this study is to test the Bravo Wireless pH system in Alberta using manometric siting to assess feasibility, patient outcomes and tolerance.


  1. Patient tolerance of the Bravo system is superior to standard pH-metry.
  2. Manometric placement of Bravo is as successful as standard pH-metry.

Our aims:

  1. To assess patient tolerance of Bravo versus standard pH-metry.
  2. To compare the success rate of manometric peroral placement of Bravo pH probe versus standard pH-metry.

Condition or disease Intervention/treatment Phase
Gastroesophageal Reflux Device: Bravo Device: Standard Care Not Applicable

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 86 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: A Prospective Assessment of pH Testing Methods in Alberta
Study Start Date : July 2008
Actual Primary Completion Date : December 2008
Actual Study Completion Date : August 2009

Resource links provided by the National Library of Medicine

MedlinePlus related topics: GERD

Arm Intervention/treatment
Active Comparator: Standard Care
Group 1 will have standard catheter based pH-metry. All participants will answer a questionnaire assessing tolerance and satisfaction of both the siting and placement methods and the 24 hour monitoring period.
Device: Standard Care
Nasally passed pH catheter sited by manometry, accompanied by battery powered data logger. Participant activated event marker in response to symptoms, meals and body position changes.

Active Comparator: Bravo pH Monitoring System
Group 2 will undergo unsedated peroral placement of the Bravo capsule. All participants will answer a questionnaire assessing tolerance and satisfaction of both the siting and placement methods and the 24 hour pH monitoring period.
Device: Bravo
Bravo pH Monitoring System sited manometrically.
Other Name: Bravo pH Monitoring System

Primary Outcome Measures :
  1. Overall discomfort with standard vs. Bravo pH-metry. [ Time Frame: 24 hours ]
    Mean overall discomfort from the pH-metry procedure between Group 1 (standard) and Group 2 (Bravo) as measured by questionnaire.

Secondary Outcome Measures :
  1. Success rate of Bravo capsule placement [ Time Frame: 24 hours ]
    As defined by completion of the manometry to find the Bravo placement depth; completion of peroral Bravo placement; adequate deployment and adherence of the Bravo capsule to the esophageal mucosa for a minimum of 20 hours.

  2. Site specific discomfort of both siting and placement procedures [ Time Frame: 24 hours ]
  3. Ability to do normal activities [ Time Frame: 24 hours ]
  4. Time off work [ Time Frame: 24 hours ]
    Difference in recorded time off work for Group 1 (standard) vs. Group 2 (Bravo)

  5. Procedure Related Costs [ Time Frame: 24 hours ]
    Procedure related costs between groups (including primary payer and societal costs)

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 75 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age 18 - 75 years
  • Able to provide written consent
  • Symptoms potentially due to acid reflux and referred for an ambulatory pH study as part of routine clinical care
  • Able and willing to potentially undergo peroral Bravo placement
  • Able to communicate adequately with the investigator and to comply with the requirements for the entire study

Exclusion Criteria:

  • Previous esophageal surgery, or any known anatomic or functional defect of the digestive tract that might make capsule passage or retrieval unsafe
  • Clinical evidence (including physical exam and/or EKG) of significant cardiovascular, respiratory, renal, hepatic, gastrointestinal, hematological, neurological, psychiatric or other disease that may interfere with the objectives of the study and/or pose safety concerns
  • Allergy to topical anesthetic
  • Any implanted electrical device such as a pacemaker, defibrillator or neurostimulator
  • Pregnant or breast-feeding females

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01364610

Canada, Alberta
University of Calgary
Calgary, Alberta, Canada, T2N 4Z6
University of Alberta
Edmonton, Alberta, Canada
Sponsors and Collaborators
University of Calgary

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Christopher Andrews, Principal Investigator, University of Calgary Identifier: NCT01364610     History of Changes
Other Study ID Numbers: Bravo
First Posted: June 2, 2011    Key Record Dates
Last Update Posted: June 22, 2015
Last Verified: June 2015

Keywords provided by Christopher Andrews, University of Calgary:
pH measurement

Additional relevant MeSH terms:
Gastroesophageal Reflux
Esophageal Motility Disorders
Deglutition Disorders
Esophageal Diseases
Gastrointestinal Diseases
Digestive System Diseases