Gastrointestinal Stenting: Indications and Techniques

Abstract

Esophageal Stenting The majority of esophageal stents are inserted for palliation of inoperable malignant dysphagia, but they are occasionally required to treat tumor recurrence at surgical anastomoses, and in benign strictures which are unresponsive to balloon dilatation. Tracheo-esophageal fistulae and esophageal leaks can also be successfully treated with covered stents. Esophageal carcinoma is a relatively common disease with a poor prognosis, accounting for 3,500 deaths per year in the United Kingdom (1). At the time of presentation 75% of patients will have disease spread to lymph nodes (2), and approximately 500/0---60% of patients are not suitable for attempted curative surgical resection. Available palliative treatments include surgery, radiotherapy, chemotherapy, rigid plastic tubes, laser therapy and self expanding metallic esophageal stents. A variety of covered and uncovered stents are available. The three most commonly used are the Wallstent (Schneider AG, Zurich, Switzerland), the Strecker stent (Medi-tech/Boston Scientific Corporation, Watertown, MA, USA), and the Gianturco stent (William Cook Europe, Bjaeverskov, Denmark). An initial esophagogram is performed to delineate the site and length of stricture. The patient lies on the fluoroscopic table in the left lateral position. Lidocaine spray is applied to the pharynx, and the patient is sedated with an intravenous agent such as midazolam. Suitable catheters and guide wires are used to cross the stricture. The catheter and guide wire are manipulated into the duodenum to provide as stable a position as possible, and the guide wire is changed for an Amplatz stiff exchange wire. A IS-mm-diameter balloon is used to predilate the stricture prior to stent deployment. We aim to deploy the stent with approximately 60% of its length above the middle of the stricture in an effort to minimize the incidence of distal stent migration. Long strictures may require the use of more than one overlapping stent. Immediately after the procedure, nonionic contrast medium is introduced into the esophagus via the catheter to look for any procedural complication, especially esophageal perforation, and to confirm stent patency. Patients remain in hospital overnight, and once they have recovered from the effects of the sedation, they are allowed to take small volumes of clear fluids orally. The following day a further esophagogram is performed with a view to proceeding to any further intervention that may be required. For example, a stent may show persistent narrowing, requiring balloon dilatation, or there may have been migration, requiring the insertion of an additional stent coaxially within the first endoprosthesis and overlapping with it to prevent further slip. If the esophagogram shows good stent position and function patients are allowed a normal diet. They are advised to cut their food into small pieces, to chew it thoroughly and to have carbonated beverages after each meal in order to clear the stent of any food debris. In any patient in whom a stent has been placed across the gastro-esophageal junction, reflux of gastric contents will inevitably occur. The symptoms are controlled by the administration of omeprazole, which is started routinely after the procedure.