Upper Gastrointestinal Endoscopy
Esophageal ulceration identified after
removal of an esphageal foreign body.
Upper gastrointestinal endoscopy is used to examine the esophagus, stomach and the beginning portion of the small intestine, the duodenum. It is often performed after radiographs (X-rays) and abdominal ultrasound to further evaluate patients with changes in appetite, weight loss, vomiting, diarrhea, intestinal bleeding, or unexplained anemia. Endoscopy can be used to diagnose foreign bodies, inflammation, inflammatory bowel disease, ulcers, tumors, and strictures of the upper gastrointestinal tract.
Uses For Upper Gastrointestinal Endoscopy
A large rubber foreign body identified
in the stomach of a goose.
In addition to visual examination of gastrointestinal tract, endoscopy can be used to:
Obtain tissue samples for cytologic and histologic evaluation. Samples are evaluated for inflammation, infection, fibrosis and cancer. This generally takes three to five days.
Remove foreign bodies that might be stuck in the esophagus or stomach. Commonly removed foreign bodies include fish hooks, bones, socks, coins and toys. Foreign bodies may prevent normal food passage down the gastrointestinal tract, leading to vomiting or regurgitation. Foreign bodies may also cause local inflammation, stricture, ulceration, and intestinal perforation. Zinc foreign bodies, pennies for example, may cause life-threatening anemia if not removed promptly.
Identify ‘occult’ gastrointestinal bleeding, e.g. bleeding into the intestinal tract that is not apparent to the owners or veterinarian. Such bleeding is a common cause of iron deficiency anemia in animals.
Remove gastrointestinal growths or polyps.
Retrieve samples for bacterial culture. Some bacteria, such as Helicobacter species, can cause chronic gastric disease. Unlike helicobacteriosis of humans, helicobacteriosis in animals can only be diagnosed by biopsy and advanced isolation techniques. Other less invasive tests – like breath tests – do not yield accurate results in animals.
Dilate pathologically narrowed parts of gastrointestinal tract. For example, narrowing of the esophagus can cause difficulty in eating that may lead to weight loss, malnutrition and regurgitation.
A gastrointestinal polyp in the overflow
tract of the stomach that was preventing
the stomach from emptying.
The patients is generally fasted for 12 hours prior to the procedure, because food in the stomach and small intestines can block the view the gastrointestinal tract and increases the risk of aspiration of stomach contents into the lungs. After being anesthetized, the patient is placed on its left side and anesthetic monitoring equipment is attached. The patient’s heart rate and rhythm, respiratory rate, blood pressure, carbon dioxide level and oxygen saturation level are closely monitored while under anesthesia to prevent and minimize anesthesia-associated complications.
The tip of the endoscope is carefully advanced through the mouth into the esophagus. As the scope is advanced down the esophagus into the stomach and small intestine, the inner lining of the gastrointestinal tract is carefully examined for abnormalities, including foreign bodies, inflammation, ulcers, and masses. Photos and videos may be collected of normal and abnormal structures and motility for documentation and further study. Gastrointestinal secretions may be removed using suction and air instilled to improve visualization of the intestinal tract. Ten to 20 biopsy samples are generally collected from the stomach and small intestine each, regardless of appearance, for histopathology. This is because tissues may be diseased even if they appear normal visually. If a foreign body is identified, it may be removed using grasping forceps, a snare or a basket retrieval device.
Upper gastrointestinal endoscopy generally takes between 20 minutes and one hour depending on the number of organs to be evaluated and number of biopsies taken. After completion of the procedure, the endoscope is slowly retracted and then the patient is recovered from anesthesia. Upper gastrointestinal endoscopy is an outpatient procedure, and most patients can go home on the same day as their procedures.
Risks and Limitations
Upper gastrointestinal endoscopy is generally considered a safe procedure. In addition to risks or limitations of endoscopy in general, the most common complication is transient worsening of gastrointestinal signs secondary to organ manipulation.