A Cochrane review included 2 studies with a total of 125 subjects. 62 patients undergoing pancreatico-duodenectomy underwent ERCP with biliary stenting and 63 had ERCP without biliary stenting prior to surgery. Pre-surgical mortality was not significantly affected by stenting (OR 3.14, 95% CI 0.12 to 79.26), while there were significantly more complications in the stented group (OR 43.75, 95% CI 2.51 to 761.8). Stenting had no significant effect on the post-surgical mortality (OR 0.75, 95% CI 0.25 to 2.24). However, post-surgical complications were significantly less in the stented group (OR 0.45, 95% CI 0.22 to 0.91). Overall mortality (OR 0.81, 95% CI 0.17 to 3.89) and complications (OR 0.50, 95% CI 0.01 to 23.68) were not significantly different in the two groups.
Comment: The quality of evidence is downgraded by imprecise results (few patients and wide confidence intervals) and by study quality (inadequate or unclear allocation concealment).