Preoperative biliary drainage in malignant obstruction: indications, techniques, and the debate over risk.

In patients with malignant biliary obstruction considered suitable for surgical resection, preoperative drainage might be expected to improve surgical outcomes by restoring liver function and improving nutritional status. In practice, however, the benefits of preoperative drainage are far from clear. Studies to date have reported differing outcomes, and some have suggested that morbidity and mortality are greater in patients undergoing drainage than in those proceeding directly to surgery. The development of clinical guidelines has been limited by the lack of convincing randomized data, which in turn has led to variations in practice. This article examines the arguments for and against preoperative biliary drainage, the conflicting data on the subject, and the techniques used.