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Esophageal pH Monitoring

Esophageal pH Monitoring Explained

Esophageal pH monitoring with impedance measures how often acid and non-acid reflux move into the esophagus during normal daily activities. A thin catheter is used to collect data while you go about your routine and track symptoms. The results help determine whether reflux is contributing to your symptoms and how well treatment is working.

Important Things to Know

Esophageal pH monitoring is a test used to evaluate gastroesophageal reflux disease and to determine the effectiveness of medications that prevent acid reflux. This test measures the amount of acid refluxing or backing up from the stomach into the esophagus (food pipe). Esophageal pH monitoring is used in several situations to assess gastroesophageal reflux disease (GERD). The first is to evaluate typical symptoms of GERD such as heartburn and regurgitation that do not respond to treatment with medications. In this situation, there may be a question whether the patient has gastroesophageal reflux disease or whether antacid medications are adequate to suppress acid production. The second is when there are atypical symptoms of GERD such as chest pain, coughing, wheezing, hoarseness, or sore throat. In this situation, it is not clear if the symptoms are due to gastroesophageal reflux. Occasionally, this test can be used to monitor the effectiveness of medications used to treat GERD. The test is often used as part of a pre-operative evaluation before anti-reflux surgery.

Timing & Schedule

Preparation focuses on medication adjustments and short-term fasting before catheter placement. You’ll follow specific guidance leading up to the test, wear the monitoring device for a full day, and return afterward for removal. Detailed instructions and exact timing are provided below.

Instructions:
Step 1.
Before Your Test (if OFF acid suppressive therapy)

This test can be performed on or off acid suppressive therapy. Please check with your physician as to whether you should stop any medications prior to the study. If you are told to stop acid suppressive medications before the study, then the following medications should be stopped as follows:

  • 7 days before test: stop taking Prilosec (omeprazole), Nexium (esomeprazole), Aciphex (rabeprazole), Prevacid (lansoprazole), Protonix (pantoprazole), Zegerid (immediate release omeprazole), Dexilant (dexlansoprazole), and similar drugs.
  • 2 days before test: stop taking Zantac 360 (Famotidine), Tagamet (Cimetidine), Axid (Nizatidine), Pepcid (Famotidine).
  • 24 hours before the test: stop taking Maalox, Mylanta, Gaviscon and Tums.
  • The day of test avoid any narcotics, benzodiazepines, and muscle relaxants as these medications can affect the results. If you have taken any of these medications, your procedure will be rescheduled to a later date.
  • Do not eat or drink anything for 4 hours before the study if undergoing pH/impedance.
Step 2.
Before Your Test (if continuing suppressive therapy)

If you were asked to obtain the study on your current regimen of acid suppression medications, then continue to take those even on the day of the test along with regular medications such as high blood pressure and heart medications. Medications that are not essential should not be taken on the day of the test until after the test is completed.

  • Do not eat or drink anything for 4 hours before the study if undergoing pH/impedance.
Step 3.
After Catheter Placement

During the 24 hours that the catheter is in place, the patient goes about his/her usual activities, for example, eating, sleeping, and working. Meals, periods of sleep, and symptoms are recorded by the patient in a diary and by pushing buttons on the recorder. The diary helps the doctor to interpret the results. The patient returns the next day for removal of the catheter. After the catheter is removed, the recorder is attached to a computer so that the data recorded can be downloaded into the computer where it is then analyzed. There are very few side effects of esophageal pH monitoring. There may be mild discomfort in the back of the throat while the catheter is in place. Most patients have no difficulty eating, sleeping, or going about their daily activities. Some patients, however, prefer not to go to work because they feel self-conscious about the catheter protruding from their nose. Should you experience discomfort that is not tolerable while the catheter is in place, or you feel the recorder is not functioning properly, contact our office.

Take Aways
Additional Details
Medication:
  • Your physician will tell you whether this test should be done on or off acid-suppressing medications.
  • If the test is done off therapy, follow the listed stop times for proton pump inhibitors, H2 blockers, and antacids.
  • If the study is done on therapy, continue your acid medications and other essential medicines as usual.
  • Avoid starting new non-essential medications on the day of the test unless approved by your doctor.
  • We cannot be responsible for your valuables (watches or various jewelry items). Please leave them at home.
  • Bring all insurance cards and a photo ID with you. Please check with your insurance company regarding prior-authorization.
  • Fee for services is required at time of check-in. Please be prepared to make a payment.
  • IGA recognizes that your time is valuable, and so is ours. If you need to cancel or reschedule an appointment, please do so more than 48 business hours prior to your scheduled appointment arrival time at 208-343-6458. Late cancellations and no shows may be assessed a $200 fee.
These instructions are a summary of how we perform catheter-based esophageal pH monitoring. Always follow the specific guidance from your provider.

Supplies Needed

pH/impedance catheter and recorder (provided)
Symptom and meal diary (provided)

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Information on this website is for education only and not a substitute for medical advice.

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