24-Hour pH Monitoring and Impedance Study
What Happens Before, During, and After
This handout explains pH monitoring. You may find it helpful to write down any questions you may have about the test and discuss them with your nurse or doctor.
What is 24-hour pH monitoring?
It is used to diagnose esophageal reflux. A small flexible tube is passed through your nose into your esophagus. (See below). The nurse connects the tube to a small recording device that measures the acid present in your esophagus. You will carry this recording device with you for 22-24 hours.
Why is 24-hour pH Monitoring Performed?
It is done to measure how often acid may be leaking into the esophagus from the stomach and if this relates to your symptoms. The esophagus has two main functions: (1) transport food from the mouth to the stomach, and (2) keep the digested food in the stomach. At the entrance to the stomach, a set of muscles work
s like a valve to stop food from coming back up into the esophagus. When this valve is not working as it should, you may have symptoms such as heartburn, pain, or cough from the acid reflux.
Before the Test
You may take your acid reflux medicine and your other medicines up to 4 hours before the study. You will be told whether your doctor wants you to stop taking acid blocking medicine.
If you have any questions, you may contact your doctor or the Digestive Health Center at the contact numbers listed below.
Day of Procedure
- Do not eat or drink for 4 hours before your test. After the tube is placed, you will be asked to eat and drink normally. If you have noticed any foods that make your symptoms worse, please have those available at home to eat during your test.
- Wear a blouse or shirt with buttons down the front. This makes it easier to change clothes later.
Follow the arrival and registration instructions in your cover letter. If you are delayed, call us at (608) 890-5000 to let us know you are going to be late. If you are over thirty minutes late, we may have to cancel and reschedule. We do our best to stay on time. After you check in, you will speak to a nurse. Please feel free to ask any questions you may have at that time. Your clinic visit will take about one hour. You will learn how to use a diary to record your symptoms and meal times during the next 22 to 24 hours.
During the Test
Your nose will be numbed and a small tube inserted through your nose and into your esophagus. An x-ray may be done after the tube is placed to check the tube position.
- You must handle the data recorder with care. Do not drop or bang it. You will carry the recording device with you for 22-24 hours.
- Do not shower or take a bath during this test.
You will return the next day to have the tube removed. This takes just a few minutes. No appointment is needed for this. Please bring your diary with you.
After the Test
Results from your diary and the pH recorder will be entered into a computer. Results of the test will be sent to your doctor. You may return to your normal diet and activities when you are done with the test.
How to Contact Us
Digestive Health Center, 8am to 5pm weekdays, (608) 890-5000.
After clinic hours, please call (608) 890-5000. Give your name and phone number with the area code. The doctor will call you back.
If you live outside of the Madison area, please call 1-855-342-9900.
UW Health Digestive Health Center
750 University Row
University of Wisconsin Hospital & Clinics
GI Procedure Clinic
600 Highland Avenue
Meriter Hospital Digestive Health Center
202 S. Park Street
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 04/24/2013
Copyright © 04/11/2013 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#5160
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