Home > Encyclopedia of Nursing & Allied Health > Gastroesophageal Reflux Scan

Definition

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal problems among children or adults. It is defined as the movement of solid or liquid contents from the stomach into the esophagus. Gastrointestinal reflux imaging encompasses methods used to visualize and diagnose GERD.

Purpose

The purpose of gastroesophageal reflux scanning is to visualize the interior of the upper stomach and lower esophagus. Such inspections assist in making an accurate diagnosis and in planning appropriate treatment.

Precautions

For all tests used to evaluate GERD, persons must not have other medical complications such as high blood pressure, asthma, or esophageal varices. They should not be experiencing other acute medical conditions.

Description

A brief description of gastroesophageal reflux disease assists in understanding the scanning methods used. Gastroesophageal reflux disease is the term used to describe the symptoms and damage caused by the back-flow (reflux) of the contents of the stomach into the esophagus. Stomach contents are usually acidic. Because of their acidity, they have the potential to cause chemical burns in unprotected tissues such as those lining the esophagus.

Gastrointestinal reflux is common in the American population. Approximately one adult in three reports experiencing some occasional reflux, commonly referred to as heartburn. Approximately 10% of these persons experience reflux on a daily basis. Most persons have very mild disease. Occasionally, persons experience burning as a result of reflux. This is described as reflux esophagitis when it occurs in the esophagus.

There are several causes of gastroesophageal reflux. These include the following:

• Incompetent lower esophageal sphincter. When the muscular sphincter that is the boundary of the esophagus and stomach relaxes, reflux can occur. This is the most common cause for gastroesophageal reflux. Reflux usually occurs when persons bend, lift a weight, or strain. Persons with esophageal strictures or Barrett's esophagus are more likely to experience gastroesophageal reflux than are others.
• Acidic irritation. Gastric contents are acidic, with a pH less than 3.9. Such acid is very caustic to the lining of the esophagus. Repeated exposure to acidic gastric contents leads to scarring. If the exposure is sufficiently severe or prolonged, strictures can develop. Occasionally, pancreatic enzymes or bile reflux into the stomach and lower esophagus. These contents are extremely acidic (with a pH less than 2.0).
• Abnormal esophageal clearance. Acid reflux is washed away by saliva that is swallowed over the course of a day. During the night, swallowing is decreased. This results in a longer contact time between acidic stomach contents and the esophagus. The net result is a chemical injury. Sjögren's syndrome, radiation to the oral cavity, and some medications (anticholinergics) also decrease the flow of saliva and can result in chemical injury. Saliva also contains bicarbonate, which neutralizes some acid content. This, too, is diminished at night, contributing to nocturnal exposure and irritation over a period of time. Other medical conditions such as Raynaud's disease and scleroderma are often associated with abnormal esophageal clearance. Hiatal hernia is present in more than 90% or persons with erosive disease.
• Delayed gastric emptying. When gastric outflow is obstructed or gastric motility is impaired, gastric contents do not leave the stomach in a timely manner. This enhances the opportunity for gastric reflux.

Heartburn associated with gastroesophageal reflux occurs 30 to 60 minutes after eating. It also occurs when a person reclines. Most persons who experience gastroesophageal reflux can obtain relief with baking soda (Alka-Seltzer) or antacid tablets. This pattern is often sufficient for diagnostic purposes. Under these conditions, physical examination and laboratory findings are usually within normal limits.

Persons with complicated GERD, or those who do not respond to the usual remedies (baking soda or antacid tablets), require special examinations. There are several imaging methods used in the diagnosis of GERD. Details concerning each of the procedures follow.

Upper endoscopy

Upper endoscopy is the standard procedure for diagnosis, determination of the degree of tissue damage, and documentation of GERD. Between half and three-quarters of all persons with GERD will display abnormalities in their esophageal mucosa. The abnormalities include erosion, tissue fragility, and erythema. Upper endoscopy is also used to document esophageal strictures and Barrett's esophagus. Approximately half of all persons who undergo endoscopy have normal findings. Endoscopy is indicated for persons who have such symptoms as hematemesis, iron deficiency anemia, guaiac-positive stools, or dysphagia.

An endoscope is passed through the oral cavity into the esophagus. The mucosal lining of the esophagus, the gastroesophageal junction, and the lining of the upper portion of the stomach are visualized directly. Biopsy specimens can be obtained at the same time.

Ambulatory esophageal pH monitoring

This test provides information concerning the frequency and duration of acid reflux. It can also provide information related to the timing of episodes of reflux. It is the standard procedure for documenting abnormal acid reflux. However, it is not needed for most persons with GERD as they can be adequately diagnosed on the basis of history or by using upper endoscopy.

In this test, a tiny catheter (about 2 millimeters) with two electrodes is passed through the nose and throat. One electrode is positioned about 5 cm above the esophageal sphincter. The other electrode is positioned just below the esophageal sphincter. Data on pH are obtained every four seconds for 24 hours. Persons tested are instructed to keep a diary recording symptoms. Special emphasis is placed on coughing episodes, meal times, time of lying down for sleep, and time of rising in the morning. The electrodes are removed after 24 hours. The patients' diaries are reviewed.

Barium esophagography

A water solution containing barium is slowly swallowed. X-rays are taken during swallowing and are analyzed for signs of reflux, inflammation, dysmotility, strictures, and other abnormalities. This test can diagnose, or provide important information about, a number of disorders involving esophageal function, including craniopharyngeal achalasia (a swallowing disorder of the throat); decreased or reverse peristalsis; and hiatal hernia.

Esophageal manometry

When surgery is anticipated, esophageal manometry is useful. It provides data about esophageal peristalsis and minimum esophageal sphincter closing pressure.

Esophageal manometry measures the pressure within the esophagus. It can be used to evaluate the action of muscle waves in the main portion of the esophagus, as well as the muscular sphincter at the end of the esophagus. A thin soft tube is passed through the nose, or occasionally the mouth. Upon swallowing, the tip of the tube enters the esophagus and is positioned at the desired location. The patient then swallows air or water while a technician records the pressure at the tip of the tube.

Preparation

Upper endoscopy

Prior to the test, persons are instructed not to eat or drink for six hours. A mild sedative is usually given to calm persons who are about to be tested.

Ambulatory esophageal pH monitoring

No special preparations are needed. A short-acting anesthetic spray is sometimes used to relieve any discomfort associated with placing the electrodes.

Barium esophagography

Prior to the test, persons are instructed not to eat or drink for six hours.

Esophageal manometry

Persons are asked not to eat or drink for the eight hours prior to the test. Prior to the test, persons are instructed not to eat or drink for six hours. An anesthetic spray is often used to reduce the irritation experienced when the manometry tube is passed through the nose and oral cavity.

Aftercare

Upper endoscopy

After the test, persons must be driven home due to lingering effects of the sedative.

Ambulatory esophageal pH monitoring

There are no special steps to be taken after the electrodes have been removed.

Barium esophagography

There are no special instructions after the test.

Esophageal manometry

There are no special instructions after the test.

Complications

Upper endoscopy

Patients may feel as if they are choking as the endoscope proceeds down the throat. Actual choking is uncommon due to sedation.

Ambulatory esophageal pH monitoring

There are no common complications.

Barium esophagography

Constipation after the test is an infrequent complication. This is routinely treated by administration of a laxative.

Esophageal manometry

Complications are very rare.

Results

Upper endoscopy

Endoscopy documents the condition of mucosa in the lower esophagus and upper stomach, evaluating the extent of GERD progression.

Ambulatory esophageal pH monitoring

Measurements of pH are used to evaluate the degree of GERD.

Barium esophagography

Barium esophagography can detect many abnormalities. including reflux.

Esophageal manometry

This documents the ability of the esophageal sphincter to close and keep stomach contents from refluxing.

Health care team roles

A family physician, pediatrician, internist, or cardiologist usually makes the initial diagnosis of GERD. A gastroenterologist usually performs the tests required for diagnosis. A radiology technologist performs the barium esophagography and a radiologist interprets it.

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KEY TERMS

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Barrett's esophagus—An abnormal condition of the (usually) lower esophagus in which normal mucous cells are replaced by changed cells. The condition is often a prelude to cancer.

Dysphagia—Difficulty in swallowing.

Erythema—Redness.

Esophageal varices—Varicose veins at the lower-most portion of the esophagus. These are easily injured. Bleeding from esophageal varices is often difficult to stop.

Esophagus—The tube that connects the mouth to the stomach.

Hematemesis—Vomit that contains blood, usually seen as black specks in the vomitus.

pH—A measure of acidity; technically, a measure of hydrogen ion concentration.

Raynaud's disease—A disease of the arteries in hands or feet.

Reflux—Backflow, also called regurgitation.

Sjögren's syndrome—An autoimmune disorder characterized by dryness of the eyes, nose, mouth, and other areas covered by mucous membranes.

Sphincter—A physiologic valve comprised of muscle.

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L. Fleming Fallon, Jr., MD, DrPH