Self-expanding stent in the upper GI tractMedical editor Trond Warloe MD
Oslo University Hospital
A self-expanding stent is installed when passage of food in the upper GI tract is constricted. This procedure is an important option especially for patients with an inoperable tumor in the esophagus. It is important the patient avoids palliative surgery as much as possible to minimize time spent at the hospital.
A stent is installed using a scope. The stent serves as a grating which expands when pushed out of its casing. Using X-ray, the stent is guided down a guide-wire. Because of tension in the metal wires, a larger opening is made through the tumor area. The stent is usually covered with a plastic membrane to keep the tumor tissue from growing in the openings of the metal grating.
- Stenosis – many patients with cancer in the esophagus or stomach have stenosis as the most prominent symptom and therefore do not receive nutrition orally. Endoscopic installation of a self-expanding stent enables most patients to obtain nutrition by mouth.
- Fistula – an esophago-tracheal fistula can be treated with a stent in both the esophagus and trachea. A fistula from the esophagus to the pleura can be covered with a stent in the esophagus. External drainage on the outside of the esophagus is usually necessary for healing to occur.
- The patient obtains nutrition orally
- Gastroscope with accessories
- Stent equipment with guide wire and weights
Installation of a stent is performed on an outpatient and inpatient basis.
The patient must:
- inform the health personnel if they have a known heart valve defect. If so, the patient will be administered a prophylaxis for endocarditis.
- inform the health personnel if they are treated with insulin.
- Inform the health personnel if they are treated with an anticoagulant or arthritis medications. These should be stopped 5 days before the procedure.
- take an X-ray and EKG if he/she is > 60 years and/or has heart disease
Before stent installation:
- Fast for the last 6 hours before the operation
The day of stent installation
- Premedication is administered.
- The patient lies in the supine position on the examination table.
- Dentures are removed.
- A local anesthetic is sprayed in the throat. This will take effect immediately.
- The patient is placed under general anesthesia.
- The scope is inserted in the mouth and down the esophagus.
- The tumor area is localized.
- The upper and lower part of the tumor is marked with lead balls on the skin using X-ray.
- The guide-wire is inserted down and the scope is pulled out.
- An insertion case with the self-expanding stent is inserted down over the guide-wire and placed according to the lead balls (still using X-ray).
- The stent is released and the insertion case is retrieved.
- X-ray and endoscopy are used to check that the stent is situated correctly.
The procedure usually lasts for 30 minutes.
It usually takes 2-3 days for the stent to fully expand to the optimal size. During this period, the patient will usually have increasing pain.
The patient is transferred immediately after the procedure as long as there are no complications. Normal hospital stay is 1-3 days.
The patient should be observed for:
- pain – adequate pain medication should be administered.
- respiration – serious breathing difficulty may be a sign of perforation in the esophagus.
- creptiation (when air leaks to surrounding tissue) – this is a sign of subcutaneous emphysema and can occur as a complication from perforation in the esophagus.
- rise in body temperature – this indicates a perforation in the esophagus.
An X-ray of the stent is performed to check that the contrast fluid passes the stent the first day after installation.
An X-ray might be taken of the stent before the patient starts to eat. Often, the patient can eat/drink until the X-ray is taken.
Complications from a self-expanding stent
Dislocation of the stent is rare, but still the most common complication.
In some cases, the tumor grows over the upper or lower edge. This requires a new stent to be placed partially in the old stent.
Stents which are placed through the cardia will make an opening from the stomach to the esophagus where there is risk of regurgitation of stomach content causing aspiration and pneumonia. There are stents available with an anti-reflux mechanism.
Abcesses can develop on the outside of the esophagus if the stent closes a fistula path from the inside without simultaneous drainage from the outside.