Esophageal pH / impedance instructions

PH/Impedance monitoring is an ambulatory 24-hour test that measures reflux of gastric (stomach) contents into the esophagus.

Before the procedure

  • You may have you regular meals on the day before the test.
  • Do not eat or drink anything after midnight. This also includes chewing gum, mints and hard candies. If you are scheduled for an afternoon appointment, you may have clear liquids 6 hours before appointment.
  • No smoking.
  • Wear a shirt or blouse that buttons in the front on the day of the pH/Impedance test.
  • You may wish to shower or take a tub bath before your appointment since you will be unable to do so for 24 hours during the test.
  • You will be asked to sign an informed consent and provide information regarding allergies, medicines you are now taking, existing medical conditions and previous surgeries.

(Medications will be discussed on an individual basis.)

During the procedure

An esophageal manometry test will be performed before the placement of the pH/Impedance catheter.

  • Your nostrils will be numbed with an anesthetic gel to allow for easier placement of the catheter.
  • The pH/Impedance catheter will be inserted through your nostrils into your esophagus, secured in place with tape and connected to a recording device.
  • The test lasts for 24 hours.
  • During the 24 hours, you will be asked to keep a diary to write down when you eat, lay down, take medications and when you have symptoms such as heartburn, chest pain, cough, etc. It is important to keep an accurate diary!
  • Eat the foods you normally consume during the test.
  • You may drink any beverage with meals, but drink only water between meals.
  • Do not chew gum or eat hard candies or mints during the test.
  • Do not take a tub bath or shower during the test.
  • After the 24 hours, please return to The Austin Diagnostic Clinic, Gastroenterology section, located on the first floor in the North entrance (map).
  • Remember to bring your diary!
  • A nurse will remove the catheter and review the diary with you.

If you experience any difficulties during the test, please let us know.

After the procedure

  • You may resume your normal daily activities.
  • Your nostril or throat may be slightly sore for 1 or 2 days.
  • Please schedule a follow-up visit with your physician to discuss the results of the test.

If you experience any problems after the test, contact your doctor.