Fractures of self-expanding metallic stents in periampullary malignant biliary obstruction.

BACKGROUND: Self-expanding metallic stents are widely used for relieving biliary duct obstruction in patients with unresectable periampullary malignancies. However, only a few studies have assessed the occurrence of fractures in these stents. PURPOSE: To determine the prevalence and significance of stent fracture after placement of self-expanding metallic stents for periampullary malignant biliary obstruction. MATERIAL AND METHODS: Over a 5-year period, 48 patients underwent placement of self-expanding metallic stents for periampullary malignant biliary obstructions. Stents were introduced 2-6 weeks after a percutaneous transhepatic biliary decompression. The medical records and relevant images were reviewed for stent patency, stent fracture, type of stent, and stent-related complications. RESULTS: Stent fracture was detected in four of the 48 patients (8%): in one patient at 1 month and in three patients between 10 and 21 months after stenting. All four fractures involved one type of nitinol stent used in 38 patients. In one of the patients, fracture was complicated by life-threatening gastrointestinal bleeding. The mean survival time for all patients was 251 days (standard deviation [SD]+/-275 days) and the mean overall patency time for all stents was 187 days (SD+/-205 days). CONCLUSION: Stent fracture occurs after placement of self-expanding nitinol stents for periampullary malignant biliary obstruction. The low reported incidence of this complication may be due to a lack of awareness of and difficulty in detecting stent fracture. Fracture should be considered as a possible contributing factor in recurrent biliary obstruction after self-expanding metallic stent insertion.

[Peroral antibiotic prophylaxis in upper gastrointestinal surgery. A study of biological availability]. / Peroral antibiotikaprofylax vid övre gastrointestinal kirurgi. En studie av biotillgänglighet.

Sixteen patients undergoing elective upper gastrointestinal surgery with presumed normal gastrointestinal function received peroral trimethoprim-sulfamethoxazole (TMP/SMZ 160/800 mg) and metronidazole (2 g) in the morning regardless of what time the operation was to be started. The concentration of SMZ in plasma was measured before and after the operation. Only 37 per cent of the patients were found to have adequate levels of SMZ concentration. Patients with grave obesity or malignant disease of the liver, biliary tract or pancreas had concentrations below the minimal inhibitory concentrations for species of Enterobacteriacae. Peroral antibiotic prophylaxis is therefore not suitable in all types of upper gastrointestinal surgery.