Fistulotomy versus standard cannulation as the primary technique for all patients undergoing ERCP with a native papilla: a protocol for a single center randomized controlled trial

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is an indispensable procedure for the management of pancreaticobiliary diseases. Post-ERCP pancreatitis (PEP) is the most common serious adverse event. One risk factor of PEP is difficulty achieving biliary access. The conventional ERCP technique involves the cannulation of the bile duct via the ampulla of Vater, followed by sphincter incision using electrocautery. Conventionally, if the standard method fails then, precut techniques have been utilized as an alternative means of gaining biliary access. The needle-knife fistulotomy (NKF) technique involves identifying the intra-duodenal segment of the bile duct and uses a needle knife to incise directly into the bile duct. This is done above and away from the natural office, thus minimizing thermal damage which may result in PEP. Our recent prospective study of 50 patients demonstrated the safety and feasibility of the NKF precut technique as a primary means of gaining biliary access. The next step is to conduct a randomized controlled trial to compare the efficacy and safety of initial NKF to the standard cannulation in a non-selective patient population undergoing ERCP. METHODS: A randomized control trial of 538 consecutive, non-selective patients with pancreaticobiliary disease undergoing ERCP at a tertiary care center in Kingston, Ontario, Canada, will be conducted. Patients will be randomized to one of two treatment groups, standard cannulation or NKF. The primary outcome of the study will be the incidence of PEP. Secondary outcomes will include rate of successful cannulation of the common bile duct (CBD), time to successful cannulation, total procedure time, difficulty of cannulation, and incidence of complications. DISCUSSION: This RCT will yield important answers regarding the efficacy and safety of initial NKF to the standard cannulation in a non-selective patient population undergoing ERCP. The results of our study could alter ERCP practices and outcomes if NKF is shown to reduce PEP risk. TRIAL REGISTRATION: ClinicalTrials.govNCT04559867. Registered on September 23, 2020