A very thin and flexible catheter is inserted through the nose and communicates with a small receiver that  measures the reflux of fluid and records events for 24 hours.

How Should I Prepare for a 24 Hour Impedance pH Study?

  • It is important that you MUST STOP certain acid-reducing medications (follow the chart below) before this test to ensure it is accurate. Do not resume taking medications until the test is over.
  • Your Physician may recommend continuing antacid therapy on a case by case basis.

What Happens During the 24 hour Impedance Study?

  • The catheter will be placed by a nurse, which generally takes less than 30 minutes to insert. Generally, you will be in a comfortable, semi-reclining or reclining position. Your nose and throat may be numbed with a spray or gel. This will minimize any discomfort associated with the placement of the small catheter through your nose and into your esophagus and stomach.
  • After your nasal catheter is in place, you will receive a reflux recorder to take home with you. Throughout the test period, the catheter will measure reflux in your esophagus and transmit this information to the reflux recorder, worn with a strap around your neck, waist, or in a big pocket. You can go about your normal activities.
  • You will also be given instructions how to record the times when you have reflux symptoms (coughing, heartburn, regurgitation), when you eat and when you lie down.
  • You are encouraged to eat normally (including foods that trigger symptoms) and go about your daily routine (do not chew gum or hard candy during the test).
  • The catheter will be taped to your cheek and/or neck. Do not disconnect the recorder from catheter until you are ready to end the test.
  • Do not shower or bathe during the test.

What Happens After a 24 hour Impedance Study?

  • Once the test period has been completed, you will need to return to the hospital/endoscopy center to have the catheter removed and return your recorder, so that your test data can be downloaded for analysis. The study will be read by your physician to diagnose your condition.
  • Your doctor will review the results of all your testing at your follow-up appointment.

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