Iatrogenic bile duct injury: a population-based study of 152 776 cholecystectomies in the Swedish Inpatient Registry.

HYPOTHESIS Older age, male sex, and low yearly hospital volume of cholecystectomy may increase the risk of bile duct injury (BDI), whereas the use of intraoperative cholangiography may decrease the risk. The incidence of BDI at cholecystectomy may have increased after the introduction of laparoscopic cholecystectomy. DESIGN Nationwide population-based study of all cholecystectomies registered in the Swedish Inpatient Registry from 1987 through 2001. SETTING All hospitals performing inpatient cholecystectomies in Sweden. PATIENTS Cholecystectomies were identified using International Classification of Diseases, Ninth and 10th Revisions surgical procedure codes. After exclusion of patients with hepatobiliary and pancreatic malignancies, patients with codes indicating reconstructive bile duct operations within 1 year after cholecystectomy were considered BDI cases. Risk factors for BDI were analyzed using multivariate logistic regression. The incidence proportion of BDI was calculated by dividing the number of cases by the number of cholecystectomies. MAIN OUTCOME MEASURES Relative risks were estimated using odds ratios with 95% confidence intervals, and incidence proportion was used to describe incidence. RESULTS Among 152 776 cholecystectomies, 613 reconstructed BDIs (0.40%) were identified. Older age and male sex were positively associated with BDI, whereas intraoperative cholangiography was negatively associated with BDI. The incidence proportion of BDI was 0.40% from 1987 to 1990, decreased to 0.32% from 1991 to 1995, and increased to 0.47% from 1996 to 2001. The mean yearly hospital volume did not affect the risk of BDI. CONCLUSIONS Older age and male sex increased the risk of BDI, whereas intraoperative cholangiography was protective. There was a small to moderate long-term increase in the risk of BDI after the introduction of laparoscopic cholecystectomy compared with the pre-laparoscopic era.