Papillary Epinephrine Injection vs Rectal Indomethacin

Overview

Post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) is the most common and one of the most undesirable major adverse events after endoscopic retrograde cholangiopancreatography (ERCP), causing significant morbidity and even mortality. The incidence rate is almost 15% in high-risk patients and no less than 3% in average-risk patients. Many factors contribute to PEP, such as patient-related and endoscopist-related factors, but mainly two mechanisms are considered in terms of physiopathology: papillary edema caused by mechanical trauma during cannulation and thermal injury with electrocautery current. Rectal NSAIDs and pancreatic stent placement are the two proven methods of PEP prophylaxis included in the guideline recommendations, but despite their frequent use, the incidence rates remain unacceptably high. There is a need for additional methods that are easy to implement, preferably low-cost, and safe to reduce the risk of PEP. Topical epinephrine applied submucosally can meet these goals. Ampullary epinephrine injection is an effective method for post-sphincterotomy bleeding. Still, to our knowledge, no study has examined its efficacy in PEP prophylaxis, except for the retrospective study we reported. There are conflicting reports on epinephrine spraying onto the papilla for PEP, but these trials are largely heterogeneous, with different dose regimens. It should also be noted that spraying epinephrine onto the papilla has a duration of action of about 1 to 5 minutes, whereas epinephrine injection has a duration of roughly 120 minutes. Given this information, a large-scale, prospective, double-blind, randomized, controlled trial is designed.

Patients will be randomized into two groups: rectal indomethacin (Group A) and epinephrine injection (Group B), by computer-generated, numbered, sealed envelopes for treatment assignments. The envelopes will be opened before the procedure without the knowledge of the endoscopists to enable blinding in the randomization process The patients in Group A will receive 100mg of rectal indomethacin alone, just before the procedure. The patients in Group B will receive a peripapillary injection of 4mg undiluted epinephrine, divided into 1mg in each quadrant of the peripapillary region, 1 to 2 cm from the papillary orifice ERCP procedures will be performed under endoscopist-directed deep sedation. Blood pressure, pulse rate, and electrocardiography will be monitored in all patients during and after the procedure. Demographic data, laboratory values, procedure parameters, and adverse events will be recorded. All patients will be hospitalized for at least 24 hours. Total procedure time is defined as the interval between esophageal intubation and duodenoscope extubation. Difficult biliary cannulation is defined as ≥5 contacts with the papilla and more than five minutes spent attempting cannulation after the first papillary contact. Cannulation time is defined as the interval between the initial contact of the sphincterotome with the ampullary mound and successful biliary cannulation. Post-ERCP adverse events will be recorded according to the American Society for Gastrointestinal Endoscopy (ASGE) ERCP lexicon. Serum samples will be obtained before the procedure and at four and 24 hours post-ERCP to measure complete blood cell counts, C-reactive protein (CRP), amylase, lipase, bilirubin, and liver enzymes. All patients will be invited for follow-up at 1 week and 1 month after the procedure.