The goal ofesophagogastroduodenoscopy is to visualize the entire upper Gl tract (to the second portion of the duodenum).
Indications
Both diagnostic and therapeutic maneuvers can he performed during the procedure. Fluid and tissue specimens can be obtained.
Diagnostic indications: Esophagogastroduodenoscopy may be used to explore upper GI symptoms or abnormalities seen on an upper Gl x-ray series. An x-ray is not a prerequisite for upper Gl endoscopy because the gaslroscope can be passed safely under direct vision even in patients with dysphagia and a possible Zenker’s diverticulum. Any pathologic process (ulcer, mass, irregularity) can be characterized by inspection and biopsy. Brush cytology may increase the diagnostic i’indings in malignant disease.
Esophagogastroduodenoscopy may be used to monitor the healing rate of gastric ulcer but is usually unnecessary with duodenal ulcer. Periodic endoscopy and biopsy in Barrett’s syndrome, a premalignant process, can detect early evidence of cancer. The best way to identify the site of upper Gl bleeding, esophagogastroduodenoscopy should be performed as soon as the patient is stable.
Therapeutic indications: These indications include dilating esophageal strictures using a dilator threaded over an endoscopically placed guide wire or using a balloon catheter passed through the endoscope. In a patient who is not a surgical candidate, an obstruclive esophageal or gastric neoplasm may be vaporized with a laser wave guide passed through the gastroscope or with a bipolar tumor probe under endoscopic guidance. With a more extensive obstructive tumor, enteral nutrition can be reestablished by precisely locating the tumor endoscopically and placing an esophageal stent prosthesis with the aid of a guide wire.
Endoscopic therapy for bleeding has markedly enhanced the value of esophagogaslroduodenoseopy. Almost all episodes of upper Gl bleeding can be controlled by using injection therapy with epinephrine or absolute alcohol or by using a thermal coagulation device. Sclerotherapy for esophageal varices and injection therapy for bleeding vessels may be performed during the initial diagnostic examination by passing a long, flexible needle-tipped catheter through the endoscope. Polyps may be resected using a wire snare loop and an electrocoagulation current to prevent bleeding.
Usually, submucosal lesions cannot be resected endoscopically. Removing foreign bodies from the esophagus or stomach may require special maneuvers, including attaching a shield that folds over sharp objects to the tip of the endoscope to prevent esophageal injury during extraction. Foreign bodies smaller than a dime frequently pass spontaneously and may not require endoscopic removal. Food bezoars can sometimes be broken up with the snare, biopsy forceps, or a strong jet of water. Percutaneous endoscopic gastrostomy has largely replaced surgical creation of a feeding gastrostomy and can be accomplished at the bedside with little risk.
Contraindications and Risks
Absolute contraindications are a recent myocardial infarction and an acuie perforated viscus. Patienls with cardiorespiratory disease and dyspnea are at special risk. Even without sedation, these patients have a slightly lowered P02; with sedation, some are particularly vulnerable lo respiratory depression. In these patients, using a small-caliber endoscope and administering additional oxygen during the procedure may be beneficial.
Procedure-
For most patienls, the only preparation is a restriction on eating and drinking for 6 h before the examination. Those with either achalasia or gastric outlet obstruction may have retained food for days and may require lavage to empty the esophagus or stomach. Light sedation with an IV narcotic or a benzodiazepine may be combined with a local anesthetic applied to the posterior pharynx. The procedure is usually performed with the patient in the left lateral position. The examiner passes the instrument under direct vision through the pharynx lo examine the entire esophagus, stomach, and duodenum. The entire procedure can be performed in 15 to 30 min.
Complications
Perforation occurs in 0.03% of examinations, and death from complications occurs in about 0.006% of cases. Most complications are caused by medication and include arrhythmias, aspiration, and cardiac arrest

Endoscopy is a general term for the visual inspection of body cavities by instrumentation. Specific terms are derived from the area being examined; thus, esophagogaslroduodenoscopy refers lo upper Gl endoscopy, and colonoscopy refers to lower GI endoscopy.
Although originally considered a procedure complementary to a barium x-ray, endoscopy is now often used as the primary tool for evaluation of the Gl tract. Conventional x-rays cannot identify color changes (eg, gastritis), bleeding, or vascular malformations, and during endoscopic examination, both biopsy and therapeutic maneuvers can be performed .
Gastrointestinal endoscopy is particularly valuable in elderly patients because their symptoms may be atypical. Usually, the elderly tolerate Gl endoscopy well. However, it should be performed only for appropriate indications because complications are more common in the elderly than in younger persons. Not only are older tissues more fragile and more easily traumatized, but older patients generally have other medical problems besides Ihe Gl complaint.
Early endoscopy for Gl bleeding may help the physician select patients lor whom early surgery is lifesaving. The diagnostic accuracy of endoscopic retrognide cholangiopancreatography (ERCP) in a patient with jaundice is unsurpassed, and the techniques lor removing stones from the bile duct and placing a stent through a bile duct compressed by a malignant tumor may avoid the need for surgery altogether. The source of unexplained Gl bleeding or iron deficiency anemia is frequently determined by colonoscopy because the blood loss often originates in the colon, an area in which x-rays may be inaccurate.
Proper training in the use of endoscopes for diagnosis and therapy is necessary to attain the experience and knowledge needed to diagnose pathologic conditions correctly and prevent complications. Short courses or weekend training sessions are not adequate for this purpose.
Most endoscopes vary in length from 30 to 185 em: a special 300-cm enteroscope^ used for the small intestine. These flexible instruments have operator-controlled tip deflection capability, which permits guidance through the intestinal lumen. A high-intensity external light source illuminates the field under examination, while the image is transmitted through fiberoptic bundles to the operator’s eye or via digitized signals (vkleoendoscope) to a television screen. An internal channel permits the passage of biopsy or grasping forceps, wire snares (for polypectomy), injection needles, and electrocoagulation or laser probes. The channel also allows fluid instillation (for flushing debris from the intestinal wall) and suction aspiration.
Before Gl endoscopy, the physician may prohibit food and drink to empty the stomach or order a purgative to cleanse the colon. Most endoscopic procedures are performed with the palient under sedalion. Because transient bacteremia infrequently occurs during endoscopy. patients at high risk for infection—those with valvular heart disease (rheumatic heart disease and valvular prosthesis), neutropenia, or artificial joint implants—should receive antibiotics, usually ampicillin and gentamicin, before the examination.
Because older patients are more sensitive to sedative and analgesic drugs, doses must be adjusted to prevent adverse reactions. Benzodiazepines are commonly used to induce preendoscopic sedation, and doses may need to be reduced by 50% to 75% to guard against cardiorespiratory depression. During endoscopy in the sedated elderly patient, the physician should frequently check skin color, pulse, and respirations to monitor the depressant effects of premedication. Continuous mechanical monitoring of oxygen saturation levels with a pulse oximeter may benefit the elderly patient. Close monitoring is even more important during emergency endoscopy because events occur quickly, and the patient’s homeostatic mechanisms may be only marginally functioning.

Benign neoplasms of (he mesentery and peritoneum are twice as common as malignant neoplasms; however, they are still rare.

BENIGN NEOPLASMS
The most common benign neoplasms are fibromas and lipomas. Most often found incidentally during routine examination, these tumors frequently grow large before causing symptoms. The most common symptoms are vague abdominal pain and bloating caused by compression or traction of adjacent structures. Intestinal obstruction may occur.
Diagnosis is usually made by x-rays that reveal extrinsic compression of the large or small bowel. Surgical excision is curative.
MALIGNANT NEOPLASMS
Malignant neoplasms of the mesentery and peritoneum, which are rare, usually include mesothelioma, fibrosarcoma, or leiomyosarcoma. Symptoms and signs include vague abdominal pain and bloating caused by traction or compression of adjacent structures and intestinal obstruction. Weight loss, anorexia, and weakness can also occur. Mesothelioma is associated with asbestos exposure.
Diagnosis is made by x-rays, including an upper GI series, barium enema, and CT scan, lhal reveal extrinsic compression or signs of invasion of the small or large bowel and other local structures. Surgery is the only effective treatment for cure or palliation. However, chemotherapy and radiation therapy may improve results for mesothelioma.