Use of endoscopically placed expandable nitinol tracheal stents in the treatment of tracheal stenosis.

OBJECTIVE: To evaluate the potential utility of a new endoscopically placed expandable tracheal stent in the treatment of benign symptomatic stenoses of the cervical trachea. STUDY DESIGN: Pilot study utilizing a prospectively followed case series. METHODS: An initial group of six patients undergoing stent placement was examined with rigid and flexible endoscopy under anesthesia immediately following stent placement and at postoperative 6 to 8 weeks. Subsequently each patient was followed clinically for a minimum of 6 months. RESULTS: All stents were well tolerated with no observed complications. Immediate reversal of symptomatic airway obstruction without the need for adjunctive tracheotomy was noted in every patient. At 6 weeks, endoscopic confirmation of complete intraluminal mucosalization without formation of any granulation tissue or scar bands within the stented areas was noted in each case. CONCLUSIONS: This preliminary pilot study supports the use of nitinol expandable tracheal stents as an alternative in the treatment of benign symptomatic tracheal stenoses.

Surgical management of complications of endoscopic sphincterotomy with precut papillotomy.

We reviewed 574 endoscopic sphincterotomy procedures. Fifty-six precut papillotomies were performed. Presenting conditions included choledocholithiasis, cholangitis, benign and malignant papillary strictures, and stenosing papillitis. Complications were identified in 16 percent: perforation in 9 percent, pancreatitis in 5 percent, bleeding in 2 percent, and pancreatic abscess in 2 percent. One patient died. Six patients required operation for complications. Perforation of the duodenum or common bile duct seen within 8 hours was managed with drainage and closure of the perforation with minimal complications. Duodenal perforations operated on later than 8 hours required more extensive procedures. All these patients had significant post-operative complications. Three patients were managed nonoperatively. Precut papillotomy carries a significantly higher complication rate than conventional sphincterotomy. Our experience suggests that there is no place for conservative management of duodenal perforation.

Dietary fiber supplementation and fecal bile acids, neutral steroids and divalent cations in rats.

Young adult rats were fed ad libitum for 4 wk on defined diets containing either no fiber, 10% levels of insoluble fiber sources [cellulose, wheat bran, alfalfa, mixed fibers (Fibyrax)], 5% levels of soluble fiber sources [pectin, guar gum, psyllium (Metamucil)] or 2% cholestyramine (Questran), a bile acid sequestrant. Fecal samples were obtained from paired rats over a 3-d period, were analyzed for neutral and acidic steroid levels and compositions and, together with the food, were assayed for divalent cations (Ca2+, Mg2+, Fe2+ and Zn2+). Animals in all groups were in balance for divalent cations, and there appeared to be no relationship between the extent of cation balance and the type of fiber fed. All insoluble fiber diets and the guar gum and psyllium diets resulted in significantly higher daily fecal mass and, in general, resulted in significant dilution of total fecal steroids. With the insoluble fibers, there was a general dilution of fecal neutral steroids, which was not apparent with the soluble fibers or cholestyramine. In addition, except for the pectin- and mixed fiber-containing diets, there was reduced bacterial conversion of the primary bile acids to secondary bile acids or metabolites.

Alterations in calcium, magnesium, iron, and zinc metabolism by dietary cholestyramine.

Cholestyramine is an effective drug for the reduction of plasma cholesterol because of its ability to sequester intestinal bile acids. Since metabolic alterations, including diminished intestinal absorption of vitamin D and osteomalacia have been reported with long-term use of this resin, the influence of cholestyramine on dietary balance of four mineral elements has been investigated. Wistar-strain rats were fed either a 2% cholestyramine or control diet for one month. Dietary intakes and fecal and urinary excretions of calcium, magnesium, iron, and zinc were determined using atomic absorption spectrophotometry during three, 3-day balance periods. Cholestyramine-fed rats had a net negative balance for calcium and a lower net positive balance for magnesium, iron, and zinc than the controls. Other effects of cholestyramine were an increased urinary excretion of calcium and magnesium, a decreased urinary zinc, and an alkalinization of urine. Blood and tissue cation content was unchanged except for a reduction in serum magnesium with resin feeding. Alterations in calcium, magnesium, and zinc metabolism might be explained by inadequate vitamin D absorption from the intestine followed by an increased secretion of parathyroid hormone. A diminished iron absorption due to resin binding could account for the reported disturbance in iron balance.