Partially Covered Esophageal Stents Cause Bowel Injury When Used to Treat Complications of Bariatric Surgery

Wei Wei, MD, Archana Ramaswamy, MD, Roger De La Torre, MD, Brent W Miedema, MD. Division of General Surgery, University of Missouri-Columbia

INTRODUCTION
The hypothesis was that a stent that is mainly silicone covered but has a portion uncovered may allow tissue ingrowth and decrease the migration rate seen with fully covered stents and still allow safe stent removal. The aim of this study was to evaluate the results of using partially covered stents for anastamotic complications of bariatric surgery.

METHODS AND PROCEDURES
This was a retrospective evaluation of a case series of patients with staple line complications after bariatric surgery that received a Boston Scientific partially covered stent at a single tertiary care bariatric center. The stents vary in length from 10-15 cm and in diameter from 18 to 23 mm.

RESULTS
From April 2009 to April 2010, 8 patients received uncovered stents on 14 separate occasions. The indications were stricture in four, acute leak followed by a later stricture in two, one with an acute leak only, and one with a perforated ulcer at the gastrojejunostomy. Single stents were placed in 12 sessions and two overlapping stents in two sessions. One patient had the uncovered proximal end of the stent in the stomach, with all others in the esophagus. Stents were removed at 25 ± 10 days. Immediate symptom improvement occurred in 12/14 stent placements. Oral nutrition was initiated in 10/14 patients within 48 hours. However, 9/13 patients had minor stent migration with the proximal end of the stent moving into the proximal stomach, though the site of pathology remained covered. The stents were difficult to removal when tissue ingrowth was present. One patient required laparoscopic removal and one required two endoscopy sessions for removal. In the 10 stents where the proximal end was in the stomach, three had gastric ulceration, three had gastric mucosa replaced by granulation tissue, and four had normal gastric mucosa. When the proximal portion of the stent (4 stents) stayed in the esophagus, the esophageal deployment zone had abnormalities: three with granulation tissue and one with denuding of the esophageal mucosa. The distal uncovered portion of the stent in the Roux limb never became embedded in the mucosa and caused minimal injury.

CONCLUSIONS
A partially covered stent was successful in keeping the site of the pathology covered and provided rapid symptom improvement and oral nutrition. The proximal end of the stent generally moved from the esophagus to the stomach probably due to esophageal peristalsis. The proximal bare area becomes embedded in the esophagus and sometimes in the stomach making removal difficult and hazardous. Partially covered stents are not safe and we no longer use them.