My doctor is interested in doing an endoscopy as well as a 24-hour pH level monitoring for GERD. What are these procedures, and what do they involve?

Robert

These two tests enable your physician to determine important information about your gastroesophageal reflux disease (GERD). Endoscopy can reveal damage caused by GERD, and ambulatory pH monitoring can show the frequency and severity of the condition.

In endoscopy, a gastroenterologist examines the lining of your esophagus by passing a fiberoptic scope into your throat. Using this viewing device, the doctor can determine whether there is inflammation (irritation or ulcer of the esophageal lining). The doctor can also look for signs of Barrett's esophagus, a potentially precancerous condition that can occurs when many years of acid reflux have damaged the lining. This condition occurs in about 15 percent of people with GERD; it is more common in patients who have had symptoms for over five years and are over 50 years of age.

Endoscopy is performed after an overnight fast. It is done on an outpatient basis, either in the gastroenterologist's office or in a hospital unit. An intravenous (IV) line is placed in order to give you sedation -- usually with a drug such as meperidine (Demerol) or midazolam (Versed), which is similar to Valium. After you are comfortably sedated, the examination is performed. The doctor may perform a biopsy (take a tissue sample) to examine under the microscope to look for the cellular changes of Barrett's esophagus. You will not feel this.

The procedure takes about 30 minutes total, plus a short recovery period before a relative or friend takes you home. You should plan to take a day off from work, but you can resume normal activities the next day. Side effects or complications -- such as bleeding and tears in the lining of the esophagus -- are extremely rare (less than one in 2,000 procedures). You may have a mild sore throat for a day, and there may be minor irritation at the IV site.

The other test you asked about, ambulatory pH monitoring, is performed to determine how much acid refluxes into the esophagus, how often, at what time of day or night, and whether your symptoms occur at the same time as your reflux. We sometimes perform pH monitoring to see whether the medicines you're on are successfully controlling your acid, both in the stomach and the esophagus.

A small tube, about 2mm in diameter (a little smaller than a telephone wire) is placed through your nose into the esophagus and connected to a microcomputer that you wear around your waist or shoulder. A small amount of tape holds the tube in place. You then go home for 24 hours, after which you return the monitor. Eating is possible, as is sleeping. You do not need to be on a special diet -- in fact, you should eat the things that provoke your symptoms. The tube may be uncomfortable, but it is generally tolerated well enough that 98 percent of patients studied complete the procedure successfully.