This information is approved and/or reviewed by U-M Health System providers but it is not a tool for self-diagnosis or a substitute for medical treatment. You should speak to your physician or make an appointment to be seen if you have questions or concerns about this information or your medical condition.| Complete disclaimer
Esophageal impedance pH monitoring
You have been recommended to undergo impedance pH monitoring.
Impedance ph monitors acid and non-acid reflux episodes in the esophagus during a 24-hr period.
You should speak to the doctor who ordered your test whether to stop these medications: PPIs, histamine2 receptor antagonists, or antacids. Do not stop taking any medication unless told to do so by your doctor.
For the test, a small tube will be gently inserted through your nostril and passed into your esophagus.
Information is transmitted from the catheter to a recording device worn on a belt around your waist. This recording device saves all the data gathered during the test.
You will be asked to keep a diary of your symptoms and activity over the next 24 hours.
The next day, you will return long enough to have the tube and recorder removed.
The information from the recording device will be compared with your diary notes.
The doctor who referred you for the test will receive a copy of the results.
Not all insurance companies reimburse for this procedure. You may need to check with your own insurance company to ensure that this is a covered benefit.
To get the most accurate information from this test, you must follow the directions listed below:
DAY BEFORE PROCEDURE:
- You may eat a normal breakfast, lunch, and dinner.
- Nothing by mouth after 12:00 midnight (except critical medications can be taken with a sip of water – for example; blood pressure or heart medications). This includes not smoking after midnight.
DAY OF PROCEDURE:
- If you take oral diabetes medications (pills): Do not take the medication the morning of your test. Bring your diabetes medication with you. Please refer to the handout, "Instructions for Patients with Diabetes (on oral agents) Having Outpatient Procedures/Tests."
- If you take insulin (1 or 2 injections per day): Take one-half (1/2) of your usual morning dose of NPH, Lente or Novolin 70/30 or Lantus insulin and NO Regular or Humalog insulin the morning of your test.
- If you take Ultralente insulin or are on 3 or more injections per day, please contact the health care provider who manages your diabetes.
- Please refer to the handout, "Instructions for Patients with Diabetes (on insulin) Having Outpatient Procedures/Tests."
- Bring any oral diabetes medicine to the appointment and take when you have lunch.
- If you normally take other medications in the morning, you may take those with sips of water.
- Please bring with you the following:
- A list of all medications you are taking
- A list of allergies you have
- Health insurance cards
- Your blue University of Michigan hospital.
- Arrive at the Medical Procedures Unit reception area. The Medical Procedures Unit is located in Room 2B355 on the Second Floor of the East End of University Hospital. You will eventually be escorted to the GI Physiology Laboratory for your test.
- If for some reason you are unable to keep your appointment, please call the Medical Procedures Unit at 734-936-9250.
- During the test, you should
- Avoid strenuous physical activity.
- Not remove the belt – THE RECORDER MUST BE WORN AT ALL TIMES FOR ACCURATE RESULTS.
AFTER THE TEST:
- There are no diet or activity restrictions. You may return to usual activities and medications immediately following the test.