Endoscopic Ultrasound

Endoscopic ultrasound (EUS) combines ultrasonography and endoscopy to visualize the GI wall and adjacent structures. The incorporation of the ultrasound probe at the distal end of the ultrasonic endoscope allows ultrasound imaging with high resolution.

Purpose

• To evaluate or stage lesions of the esophagus, stomach, duodenum, pancreas, ampulla, biliary ducts, and rectum
• To evaluate submucosal tumors and large folds
• To localize endocrine tumors

Patient preparation

• Explain to the patient that this procedure permits visual examination of tumors and large folds in the GI tract.
• Check the patient's medical history for allergies, medications, and information pertinent to the current complaint.
• Instruct the patient to fast for 6 to 8 hours before the test.
• Describe the procedure to the patient. Tell him who will perform it and where and that the test generally takes 30 to 90 minutes.
• For an esophagogastroduodenoscopy (EGD) EUS, explain that a flexible instrument will be passed through the mouth and into the esophagus, as in an EGD.
• If a sigmoid EUS is to be performed, tell the patient that the scope is well lubricated to ease its insertion through the anus, that it initially feels cool, and that he may feel an urge to defecate when it's inserted and advanced.
• For the sigmoid EUS, the patient may have to take a laxative the evening before, if ordered.
• Inform the patient that he may receive an I.V. sedative to help him relax before the endoscope is inserted. If the procedure is being done on an outpatient basis, advise the patient to arrange for someone to drive him home because conscious sedation may affect his reaction time and reflexes, even though he may feel fine.
• Make sure the patient or a responsible family member has signed the consent form.

Procedure and posttest care

• Obtain baseline vital signs and leave the blood pressure cuff in place for monitoring throughout the procedure, according to facility policy. Throughout the procedure, observe the patient's skin color, temperature, and dryness; abdominal distention; level of consciousness; and pain tolerance.
• Follow the procedures for EGD or sigmoidoscopy, depending on which type of EUS is to be performed.

Precautions

• This procedure is generally safe but call cause perforation of the esophagus, stomach, or duodenum, as in EGD, or of the intestine, as in sigmoidoscopy or colonoscopy,

Normal findings

EUS usually reveals normal anatomy with no evidence of tumor.

Abnormal findings

Refer to the abnormal findings for EGD, colonoscopy, endoscopy, and sigmoidoscopy.

Interfering factors

• Esophageal stricture (hinders passage of the endoscope)
• All interfering factors listed under EGD - endoscopy, colonoscopy, and sigmoidoscopy.