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Ambulatory Esophageal Reflux pH Monitoring


This information is intended only to provide general guidance. It does not provide definitive medical advice. It is important that you consult your doctor about your specific condition.

24-hour ambulatory esophageal reflux pH monitoring is an outpatient procedure in which a tube with sensors is inserted through the nostril into the esophagus to measure reflux. When this test is done, the patient will spend the next 24 hours with a very thin catheter leading from the nostril to a small recording box carried on a shoulder strap or belt clip. The catheter has pH sensors to measure the quantity of acid entering the esophagus. Dr. Harary and some other specialists use a more sophisticated catheter that also has other sensors (impedance sensors) that measure non-acid stomach contents that back up into the esophagus, since reflux symptoms may occasionally occur even without acid. This test is often used to help the doctor understand if reflux is actually causing the symptoms, to explain why medications may not be helping, and before undergoing surgery for GERD.

Another, less commonly used, test to study gastroesophageal reflux disease (GERD) is the Bravo reflux-monitoring capsule. This small capsule is attached to the inner lining of the esophagus either during an upper GI endoscopy (EGD) or by using a small introducing catheter that is passed through the mouth after your throat has been numbed with an anesthetic spray. The capsule measures the presence of acid in your esophagus and transmits the date by radiotelemetry to a small recording box that you wear on your belt or shoulder strap for 48 hours.

Preparation For The Study

When the doctor plans the ambulatory esophageal reflux pH monitoring test with the patient, they will decide whether or not acid-reducing GERD medications should continue to be taken during the test; if these medications will not be used, they should be stopped 5 days in advance. During these 5 days, over-the-counter antacids, such as Tums, Maalox, Mylanta, Gaviscon, or Rolaids, can be taken for symptom, but they should not be used for 8 hours before the procedure. If the doctor wants you to continue taking the GERD acid-reducing medication during the test, you should not take it on the day of the test until immediately after the catheter is placed; therefore, you should bring the pill with you when you come for the test. In order to prepare for this test, you should not eat solid foods for 6 hours or drink anything for 3 hours before, as the stomach should be empty. Since many medications can affect the esophagus, you should discuss with your gastroenterologist each medication that you are taking. Your gastroenterologist may have you temporarily stop one or more of your medications before your test.

The Esophageal Reflux Monitoring Procedure

Prior to the insertion of the probe, a thin flexible esophageal manometry catheter is inserted into your esophagus through your nostril to take measurements in order to ensure proper placement. First, your nostril is numbed using a local anesthetic gel. Then, while taking small sips of water, a thin, lubricated recording catheter is passed through your nostril into the back of the nose and throat and then into the esophagus. After taking measurements, that tube is then removed, and the tube with reflux/pH sensors is inserted in its place.

Once the insertion is completed, the tube is taped to your nostril and you are fitted with a recording device which will be worn for the next 24 hours on your belt or a shoulder strap. There may be an irritated feeling of the nose and slight gagging during the passage of the catheter, but it usually lasts for 1 minute or less. The procedure takes 30 minutes, after which you are free to continue a normal routine.

After An Esophageal Reflux Monitoring Study

During the 24 hours that the catheter is in your nose, you should try to eat normally and conduct typical daily activities as much as possible; you may feel the presence of the catheter, but it should not hurt or limit eating or drinking. No shower or bath is permitted. The next morning, you return the recording box to the same medical site where it was placed, and the catheter is easily removed. The information provided by the data recorder is reviewed and analyzed by the physician and will be discussed with you, although it may take up to 2 weeks for the data to be analyzed.


Albert M. Harary, MD
110 East 55th Street, 17th Floor
Midtown East/Upper East Side

New York, NY 10022
Phone: 212-702-0123

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