Sphincterotomy

Endoscopic sphincterotomy is the cornerstone of therapeutic ERCP. A controlled cut through the major papilla using a sphincterotome with electrocautery enlarges the orifice and divides the biliary or pancreatic sphincter, allowing instrumentation of the duct, stone extraction, stent deployment, and durable drainage. The cut is oriented along the 11–12 o'clock axis of the bile duct in most cases.

Cut technique balances depth and length against bleeding and perforation risk. Pure cutting current is avoided — blended current (Endocut, ERBE) reduces bleeding by alternating cutting and coagulation phases. The cut is extended in small increments while the orientation is reassessed. Stopping at the transverse fold (or before crossing the duodenal wall) limits perforation risk.

Post-sphincterotomy bleeding is the most common bleeding-related ERCP complication (1–2% of cases). Active bleeding is managed with diluted epinephrine injection plus a second modality — bipolar or monopolar coagulation, hemoclips, or balloon tamponade. Self-expanding fully-covered metal stents are highly effective for refractory bleeding because they apply circumferential tamponade across the cut. Delayed bleeding can present hours to days later and follows the same management algorithm.