Purpose: The esophageal impedance pH test evaluates the extent of gastric reflux into the esophagus over a prolonged period of time – typically 24 hours. Sensors on the catheter measure the level of acidity at various levels in the esophagus, as well as reflux of stomach contents (regardless of its level of acidity) up the esophagus. It is the most accurate test to document gastroesophageal reflux (GERD), and is generally our preferred test because it measures acidity at different levels and measures “nonacid” reflux, and has the best ability to correlate symptoms (e.g.heartburn) with reflux events.
Description: In the esophageal impedance pH test, a small catheter (tube) will be placed into your esophagus through your nose. This catheter is very thin, 2mm in diameter, and is connected to a pocketsized recording device that will hang over your shoulder. The catheter is inserted in our office, and you should go about as much normal activity as you can for the 24hour duration of the test after you leave our office. The tube is connected to a small receiver, so you may not shower during the study. You will need to return to the office the following day (24 hours later) to have the tube removed.
Risks: Patients may experience some irritation and discomfort in the back of the throat during the esophageal impedance pH procedure. Over 90% of patients are able to complete the procedure. Rarely, refractory stimulation of the gag reflex may prohibit completion, in which case alternative plans can be made to complete the reflux testing.
Alternatives: In some patients who are unable to complete the test, or in whom more prolonged (>24 hours) monitoring is thought necessary, the Bravo capsule pH test is an alternative.
Preparation: The most accurate results of this test are obtained if you have been off of your reflux medication (Prilosec, Prevacid, Dexilant, etc.) for 7 days. You may take Pepcid, Zantac, or Tagamet up until 2 days before the test. You may take Tums, Mylanta, and Gaviscon up until 6 hours before the procedure. During the test, please do not take any antacid medications until the tube comes out. Once the tube is out, you may return to your regular medications.
The receiver is attached to the catheter and it cannot get wet. This means you cannot shower until the tube is removed the following day. The catheter is visible and will be taped to your nose for the duration of the test.
Once the catheter is placed, we ask that you not take any antacid medications for the 24 hour period.