3rd UEGW Oslo 1994 A43 period, and the cost-effectiveness hereby could be achieved. It is postulated that laparoscopic vertical banded gastroplasty will be an attractive alternative in the treatment of morbid obesity. The benefit of routine intraoperative cholangiography is debated in Norway. The main argument for peroperative cholangiography has been to visualize bile duct anatomy, and hence avoid CBD injuries. If this is important, the Norwegian national registry would be expected to reveal a
... frequency of CBDinjuries above other countries. Methods: A national registry was established in April 1993, including all patients undergoing cholecystectomy. Most Norwegian hospitals had bythen practiced the laparoscopic technique for some time, and the period does not cover the first part of the learning curve. Also patients operated with the open technique were included. Indications, preoperative investigation and health condition together with per-and postoperative complications were recorded. Results: During the first nine months 906 patients were registered, 705 operated laparoscopically, 201 openly (22%). Only in nine of the laparoscopic patients (1.2%) peroperative cholangiography was performed. 75 patients in the laparoscopic group (1 1 %) were converted to open technique. Altogether 135 patients underwent an emergency operation due to acute cholecystitis, 58 laparoscopically, 77 openly. Serious complications in the laparoscopic group were two full CBD transections (0.3%), one partial CBD injury (sidehole), five perforations of visceral organs with Verres needle and one sepsis. One patient died form myocardial infarction after laparoscopic cholecystectomy (mortality 0.1%). In the open group, two patients died from myocardial infarction and one from septic shock due to cholangitis (mortality 1.5%). Other complications to open cholecystectomy was one partial CBD injury (sidehole) and four sepsis. Conclusion: Our main quality problem in surgical treatment of gallstones is the high mortality after open cholecystectomy. The frequency of CBD injuries is similar to other countries. The aim of the study was to compare a fixed-sample and a sequential design with regard to study duration, sample size and medical results in a real-life situation. A randomized study comparing laparoscopic and conventional cholecystectomy was carried out with a fixed sample design parallel to a sequential design. The main variable was duration of postoperative convalescence. In the fixed-sample trial the necessary number of patients was calculated to be 72. The sequential trial was conclusive after inclusion of 24 patients and reduced the study duration from 43 to 18 weeks. The mean difference in duration of postoperative convalescence between the two surgical methods was 25.8 days in the fixed sample trial and 27.5 days in the sequential trial in favour of laparoscopic cholecystectomy (p < 0.01). Additionally the sequential trial reached the same conclusions as the fixed-sample trial for all the observed variables except for one. The study indicates that sequential designs should be used more frequently in clinical trials in order to involve the smallest possible number of patients necessary to reach a conclusion.