Objective Investigate success rates of cannulating a ‘virgin’ papilla during endoscopic retrograde cholangiopancreatography (ERCP) at a tertiary referral centre; determine reasons for failure and propose learnings for consideration in future revision of success benchmarking.

Design Review of all ERCPs recorded on Endosoft database from 2006 to 2012 (n=1862). Specifically, ‘virgin’ papillae, defined as those with no evidence of prior surgical intervention, stents in situ or sphincterotomy (n=947). Virgin papillae present the most challenging target for endoscopists.

Setting Gastroenterology department, St Thomas’ Hospital, London.

Patients All patients who underwent an ERCP recorded on Endosoft from 2006 to 2012 (n=1134). A proportion of these patients underwent repeat procedures, all considered virgin provided the aforementioned criteria were met.

Interventions None, retrospective audit and benchmarking exercise.

Main outcome measures Determine criteria for successful cannulation of a virgin papilla.

Results Overall success of cannulation of a virgin papilla at ERCP was 79.5%, 753 out of a total of 947 virgin papillae cases. Per patient with a virgin papilla, the success rate was 79.7%, 693 out of 869. Eliminating cases with features complicating cannulation increased success rates to 86% and 87%, respectively. Chronic pancreatitis was the single Indication associated with a failed cannulation (OR=3.9, CI 2.1 to 7.1), while biliary stones were significantly associated with a successful cannulation (OR=0.3, CI 0.2 to 0.4). Reasons for failure included patient agitation (OR=27.1, CI 7.9 to 92.7), duodenal stricturing (OR=12.5, CI 5.5 to 28.5), previous anatomy-changing surgery (OR=12.2, CI 3.3 to 45.4), tumour impingement (OR=9.5, CI 4.1 to 22.3) and equipment failure (OR=7.9, CI 1.4=43.5).

Conclusions The Joint Advisory Group’s 80% success rate for completion of therapeutic intent must be viewed in light of published difficulty rating scales, if fair comparisons and standards are to be met. This highlights the need for standardised success criterion for ERCP training and accreditation.