Patient-related factors associated with successful cannulation by trainees during hands-on endoscopic retrograde...

Hands-on endoscopic retrograde cholangiopancreatography (ERCP) training is essential for trainees to grasp the technique. Cannulation success rate (CSR) is considered one of the main indicators of competency of trainees. We aimed to investigate whether patient-related factors had an impact on the CSR of trainees.

A post hoc analysis of data from two multicenter studies (NCT02002650 and NCT03057769) was conducted. Patients aged 18-90 years with native papilla undergoing ERCP were eligible for this study. Only procedures involving trainees in centers strictly following "10-min criteria" for initial cannulation were enrolled. Primary outcome was CSR by trainees.

From December 2013 to October 2017, 20 trainees in four centers were involved in initial cannulation in 1044 patients with native papilla. Primary CSR by trainees was 61.0% (436/715), 31.5% (70/222) and 44.9% (48/107) in patients with common bile duct stone (CBDS), biliary stricture (BS) and other indications, respectively (P < 0.001). In multivariate analysis, indication of BS (OR, 0.31; 95% CI, 0.22-0.44; P < 0.001) and presence of type A diverticulum (OR, 1.69; 95% CI, 1.23-2.33; P = 0.001) were both independently associated with cannulation success of trainees. Biliary infection was significantly higher in the BS than in the CBDS group (3.6% vs 0.7%, P = 0.004), whereas other post-ERCP complications were comparable between the two groups.

Indication of BS and the presence of type A diverticulum were independently associated with the success of cannulation by trainees. These findings indicate that greater effort is needed for trainees to improve the ability of cannulation in BS.