ESOPHAGEAL pH TESTING
The esophagus is a muscular tube that that mainly functions to propel food from the back of the mouth to the stomach. It does this by contracting and relaxing in a coordinated fashion. There are also two sphincters to prevent food, digestive enzymes or acid from refluxing back up. The lower esophageal sphincter (LES) sits just above the stomach and acts as the main barrier against reflux. When the esophageus is not working properly, one may have a variety of symptoms including heartburn, trouble swallowing, and chest pain.
Patients with GERD, Non-cardiac chest pain, chronic cough or hoarseness. Also utilized in patients with GERD planning to undergo anti-reflux surgery.
pH MONITORING PROCEDURE
pH is the measure of acidity or alkalinity. An esophageal pH test measures how often the stomach acid refluxes up into the lower esophagus. There are two different techniques for esophageal pH testing:
- Nasal tube (Old Technique) – A thin flexible tube with a pH probe containing pH probes is gently inserted through the nose and into the esophagus. Once in proper position it is taped to the nose and attached to a portable recorder that is carried at the waist. Over a period of about 24 hours, the acid level in the lower esophagus is constantly measured and recorded. When the patient experiences symptoms of reflux or chest pain, a button is pushed on the recorder. This marks the time to see how the symptoms relate to the acidity levels measured by the probe. The recording is then analyzed by a computer and then reviewed by your doctor.
- BRAVO (New Technique) - The Bravo System is designed to minimize the discomfort associated with transnasal catheters. Bravo is the world's first catheter-free pH system that allows patients to enjoy their regular diet and activities without the embarrassment and discomfort associated with traditional pH monitoring.
By replacing the catheter in the esophagus with a small capsule containing a radiotransmitter, patients using the Bravo system can participate in their everyday activities during the pH study period. The study results obtained with a Bravo system are more representative of a patient's normal day, and because 48 hours of a data can be recorded, more data is available to the physician.
The Bravo capsule
The miniature Bravo pH capsule is approximately the size of a gel cap.
The capsule is temporarily inserted by means of a customized delivery system, and is often placed during an endoscopy. Once the capsule is in place, the delivery system is removed. Data is transmitted to a receiver worn by the patient which is the size and weight of a conventional pager. The capsule detaches itself from the esophageal wall within 72 hours of placement and is eliminated silently and spontaneously when going to the toilet.
Preparation for these studies is very simple. You should not eat or drink any food or liquids for about 8 hours before the exam. Small sips of water are OK. Antacid tablets are permissible until the night before the test.
Certain medications can interfere with these tests. You should review with your doctor all medications that you are taking to determine which should and should not be taken before these tests. In general, the following medications should be stopped at least 72 hours before testing. However, do not stop taking any medications without first consulting with your doctor.
- Caffeine (coffee, tea, cola, chocolate)
- Alcohol (beer, wine, liquor)
- Tagamet, Axid, Zantac, Pepcid, cimetidine
- Prilosec, Prevacid
- Propulsid, Reglan (metoclopramide)
- Donnatal, Librax, Levsin
- Urecholine (bethanechol)
- Erythromycin, E-mycin
- Nitroglycerin, Isordil
- Calcium Channel Blockers Procardia, Adalat, Calan, Cardizem, etc
- Beta-Blockers Corgard, Inderal, Lopressor, Tenormin, etc
The transnasal tube 24 hour test may cause some discomfort within the nose and sore throat during and after the procedure. The wireless (BRAVO) testing system is believed to be safe. There is only a very small chance of the capsule becoming retained within the body.