.jpg)
Reflux Testing (pH Study)
Reflux testing measures acid and non-acid reflux activity over time to help evaluate GERD and other conditions. Learn how Dr. Colin Dunn uses pH impedance and wireless Bravo monitoring in Los Gatos.
What is Reflux Testing?
Reflux testing is a group of studies that measure how much reflux activity happens in the esophagus over time. Unlike an upper endoscopy, which looks at the physical lining of the stomach and esophagus, reflux testing records how often stomach acid enters the esophagus and how long it stays there.
This objective data helps determine if symptoms like heartburn or chronic cough are associated with reflux. It is especially useful for patients who have symptoms but a normal-appearing endoscopy.
How Reflux Testing Works
Depending on the test type, a thin catheter or a wireless capsule measures acidity levels in the esophagus for 24 to 96 hours while you follow your normal daily routine.
What it measures
• Acid reflux events and how often they occur
• Weakly acidic or non-acid reflux events (with pH impedance)
• How far reflux travels up the esophagus
• How long acid remains in the esophagus
• The link between your reported symptoms and actual reflux events
What it tells Dr. Dunn
• Whether abnormal reflux is objectively present
• If symptoms like chronic cough or throat clearing correlate with reflux events
• How your symptoms respond to acid-suppressing medication during the study
• If you meet the clinical criteria for reflux or hiatal hernia surgery
• If your symptoms may be related to a different condition that mimics reflux
When is Reflux Testing Used?
Reflux testing is often recommended when a diagnosis is unclear, when symptoms persist despite medication, or as part of the evaluation before surgery.
It helps determine why heartburn, regurgitation, or sour taste continue even when you are taking acid-suppressing medication.
For patients with chronic cough, throat clearing, or hoarseness, testing shows if these symptoms align with reflux activity.
It provides objective documentation of reflux to help guide the choice of the most appropriate surgical or endoscopic treatment.
The Patient Experience
Your experience will depend on whether you have a catheter-based study or a wireless capsule test. Both allow you to continue most daily activities.
During diagnostic endoscopy
• For catheter-based tests, a thin, flexible tube is placed through the nose and stays in for 24 hours.
• For wireless tests, a small capsule is attached to the esophagus during a sedated endoscopy.
• You will wear a small recorder that receives data from the catheter or capsule.
• You will keep a diary or press buttons to record when you eat, sleep, and feel symptoms.
• The capsule later detaches on its own and passes naturally through your digestive tract.
During surgery
Reflux testing is not performed during surgery. However, the data collected from this test is important for planning a reflux operation or hiatal hernia repair. It helps Dr. Dunn evaluate whether surgery is an appropriate option and provides objective evidence to guide the choice of surgical technique for your specific needs.
Most patients find the testing manageable and appreciate that they can go about their normal day while the equipment collects objective data to help explain their symptoms.
Why Reflux Testing Matters
Objective testing helps avoid using surgery as a guess. Because reflux symptoms can overlap with other conditions like swallowing disorders or delayed stomach emptying, this data helps Dr. Dunn match treatment to the actual cause of your symptoms. This careful approach helps prevent unnecessary procedures and supports informed treatment planning.
Want to understand how this applies to your case?
Book a consultation and Dr. Dunn will walk you through exactly how EndoFLIP is used in your specific planned procedure.
Which Procedures Use This?
Reflux testing provides the objective evidence needed to plan several different treatments and surgeries for GERD and hiatal hernias.
Used in these procedures
• Laparoscopic hiatal hernia repair
• Fundoplication surgery
• LINX reflux surgery
• Endoscopic GERD therapy
Not used in these procedures
Reflux testing does not replace an upper endoscopy for looking at the lining of the esophagus, nor does it replace manometry for measuring muscle function. It is important to note that esophageal manometry does not guide the placement of a wireless Bravo reflux capsule. Wireless pH testing cannot be used by patients with pacemakers, neurostimulators, or certain metal allergies. The test is one part of a complete evaluation and should be interpreted alongside other diagnostic findings.
Frequently Asked Questions
A reflux study measures acid or non-acid reflux activity in your esophagus over an extended period. This objective data helps your doctor determine if reflux is the true cause of your symptoms, especially when an endoscopy appears normal. The results are also useful for planning medical treatment or preparing for potential antireflux surgery.
Preparation usually involves fasting for four to six hours before the test begins. Your care team will provide specific instructions on whether to continue or stop your acid-suppressing medications. If you are receiving a wireless capsule, you must discuss any metal allergies or implanted medical devices with your doctor and arrange for a driver after the procedure.
Depending on the test, a thin catheter is placed through the nose or a wireless capsule is attached during an endoscopy. You will carry a small recording device and continue your normal daily activities like eating and sleeping. Some patients notice mild throat discomfort or a vague chest sensation while the equipment is in place.
Your doctor will review the recorded data to see how often reflux occurs and if it correlates with the symptoms you tracked in your diary. These findings are evaluated alongside other diagnostic results to help determine the most appropriate management plan. This objective information helps ensure that any recommended medical or surgical treatments are tailored to your specific needs.
