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Esophageal pH Assessment - Impedance Monitoring

Esophageal pH Assessment Monitoring

What is esophageal impedance monitoring?

The esophageal impedance monitoring procedure is a complementary test and is used in combination with esophageal pH acid monitoring to evaluate the presence in the esophagus of non-acid reflux content from the stomach. Although some reflux is normal, excess reflux may damage the lining of the esophagus and cause symptoms such as chest pain, heartburn, difficulty or painful swallowing, cough, hoarseness or asthma.

A small (2 millimeter) catheter is inserted through your nose, down the back of your throat and into your esophagus. The tube is taped in place on your nose and has a long cord that is attached to a portable data recorder. You wear the recorder in a pouch that has a strap that goes around your waist or neck.

How should I prepare for the procedure?

  • You may have 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.
  • You may take certain necessary medications with a small sip of water up to two hours before the test. Please check with your doctor regarding any medications you take.
  • Notify the nurse or doctor if you are diabetic! Follow your doctor’s instructions regarding insulin dosage and when to take your pills for diabetes.
  • 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.
  • Please wear a shirt or blouse that buttons in the front. You may also wish to shower or bathe before your appointment, as you will be unable to do so for 24 hours during the duration of the test.

Unless instructed otherwise by your physician:

  • Stop all PPIs (Prilosec, Nexium, Aciphex, Prevacid, etc.) 14 days prior to your procedure.
  • You need to stop all H2 Blockers (Pepcid, Zantac, Tagamet, etc.) 72 hours prior to your procedure.
  • You need to stop any promotility agents such as Reglan (metoclopramide), Carafate and Bentyl 48 hours prior to your procedure.
  • You need to stop antacids (e.g., Tums, Maalox, Mylanta, Rolaids) 24 hours prior to testing.

What can I expect during the procedure?

  • The test will last for 24 hours during which you will be asked to keep a diary of your activities and your symptoms – when you eat, lie down, take medications, and when you have symptoms such as heartburn, chest pain, coughing, etc. It is very important to be accurate when keeping your diary!
  • No sedatives will be given for this procedure; however, your nostril will be numbed with an anesthetic gel to allow for easier placement of the catheter.
  • A very small, flexible catheter (about the size of a spaghetti noodle) is inserted through your nostril and advanced to your esophagus.
  • The catheter will be attached to a recording device that measures your reflux activity for 24 hours.
  • Eat the foods you would normally eat per the instruction sheet.
  • You may drink beverages listed on the instruction sheet with meals; however, you may only have water between meals.
  • Do not chew gum, eat hard candies or have mints during the test.
  • Do not shower or take a bath during the test.
  • After 24 hours you will need to return to the Endoscopy department. You will need to remember to bring your diary!

What happens after the procedure?

  • You may resume your normal daily activities.
  • Please schedule a follow-up visit with your doctor to discuss the results of your test.
  • You will have the name and phone number of the nurse to call should you experience difficulty during the test.
  • Complications of this procedure are exceedingly rare, with the most significant being esophageal perforation. Sometimes your nose might bleed and you may have a sore throat for one to two days after the test.