What is an upper gastrointestinal series?
An upper gastrointestinal series (UGI) is a radiographic (X-ray) examination of the upper gastrointestinal (GI) tract. The esophagus, stomach, and duodenum (first part of the small intestine) are made visible on X-ray film by a liquid suspension. This liquid suspension may be barium or a water-soluble contrast. If only the pharynx (back of mouth and throat) and esophagus (a hollow tube of muscle extending from below the tongue to the stomach) are examined with barium, the procedure is called a barium swallow.
X-rays use invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs on film. X-rays are made by using external radiation to produce images of the body, its organs, and other internal structures for diagnostic purposes. X-rays pass through body tissues onto specially-treated plates (similar to camera film) and a “negative” type picture is made.
Fluoroscopy is often used during an upper GI series. Fluoroscopy is a study of moving body structures — similar to an X-ray “movie.” A continuous X-ray beam is passed through the body part being examined, and is transmitted to a TV-like monitor so that the body part and its motion can be seen in detail. In an upper GI series, fluoroscopy allows the radiologist to see the movement of the barium through the esophagus, stomach, and duodenum as a person drinks.
What is the upper gastrointestinal tract?
The upper GI tract is the first part of the GI tract, which includes a series of hollow organs joined in a long, twisting tube from the mouth to the anus—a 1-inch-long opening through which stool leaves the body. The upper GI tract includes the mouth, esophagus, stomach, duodenum, and small intestine. The duodenum is the first part of the small intestine.
Drawing of the digestive tract within an outline of the human body. The mouth, esophagus, stomach, duodenum, small intestine, and anus are labeled.
The upper GI tract
The esophagus carries food and liquids from the mouth to the stomach. The muscular layers of the esophagus are normally pinched together at both the upper and lower ends by muscles called sphincters. When a person swallows, the sphincters relax to let food or drink pass from the mouth into the stomach. The muscles then close rapidly to prevent the food or drink from leaking out of the stomach back into the esophagus. This process is automatic and people are usually not aware of it, though people sometimes feel food in their esophagus when they swallow something too large, try to eat too quickly, or drink very hot or cold liquids.
The stomach slowly pumps the food and liquids into the small intestine, which absorbs needed nutrients. The body digests food using the movement of the muscles in the GI tract, along with the release of hormones and enzymes.
Why is an upper gastrointestinal series performed?
An upper GI series can help diagnose the cause of
- abdominal pain
- nausea and vomiting
- problems swallowing
- unexplained weight loss
An upper GI series can also show
- abnormal growths.
- esophageal varices—abnormal, enlarged veins in the lower part of the esophagus.
- gastroesophageal reflux, which occurs when stomach contents flow back up into the esophagus.
- a hiatal hernia, or when the upper part of the stomach slips through the diaphragm and moves up into the chest. The diaphragm is the muscle wall that separates the stomach from the chest.
- inflammation, or swelling, of the GI tract.
- scars or strictures—abnormal narrowing of openings in the body.
- ulcers—sores on the stomach or intestinal lining.
How does a person prepare for an upper gastrointestinal series?
A person prepares for an upper GI series by
- talking with a health care provider
- clearing the upper GI tract
Talking with a health care provider. A person should talk with his or her health care provider about medical conditions he or she has
all prescribed and over-the-counter medications, vitamins, and supplements he or she takes
Women should let their health care provider know if they may be pregnant to avoid potential risks to the developing baby. The health care provider will take special precautions to minimize the exposure to radiation, or he or she may suggest a different procedure.
Clearing the upper GI tract. This procedure uses x-ray images to examine the upper GI tract during the procedure. The x ray can’t show the lining of the organs clearly if food or drink is inside the upper GI tract. To ensure the upper GI tract is clear, health care providers usually advise people not to eat, drink, smoke, or chew gum during the 8 hours before the procedure.
How is an upper gastrointestinal series performed?
An x-ray technician and a radiologist—a doctor who specializes in medical imaging—perform an upper GI series at a hospital or an outpatient center. A person does not need anesthesia. The procedure usually takes about 2 hours to complete. However, if the barium moves slowly through the small intestine, the test may take up to 5 hours to complete.
For the test:
- the person stands or sits in front of an x-ray machine and drinks barium, which coats the lining of the upper GI tract
- the person lies on the x-ray table and the radiologist watches the barium move through the GI tract on the x rays and fluoroscopy
- the technician may press on the abdomen—the area between the chest and hips—or ask the person to change positions to fully coat the upper GI tract with the barium
If a person has a double-contrast study, he or she will swallow gas-forming crystals, which activate when they mix with the barium. The gas expands the barium-coated stomach, filling it with air and exposing finer details of the upper GI tract lining. The technician will take additional x rays.
What can a person expect after an upper gastrointestinal series?
After an upper GI series, a person can expect the following:
- bloating or nausea for a short time after the procedure
- to resume most normal activities after leaving the hospital or outpatient center
- barium in the GI tract that causes stools to be white or light colored for several days after the procedure
A person should carefully read and follow the discharge instructions, which will explain how to flush the remaining barium from the GI tract. The radiologist will interpret the images and send a report of the findings to the person’s health care provider.
What are the risks of an upper gastrointestinal series?
The risks of an upper GI series include
- constipation from the barium—the most common complication of an upper GI series.
- an allergic reaction to the barium or flavoring in the barium.
- bowel obstruction—partial or complete blockage of the small or large intestine. Although rare, bowel obstruction can be a life-threatening condition that requires emergency medical treatment.
Radiation exposure can cause cancer, although the level of radiation exposure that leads to cancer is unknown. Health care providers estimate the risk of cancer from this type of test to be small.