SOCCER: Study Of forCeps Cannulation During ERcp

Endoscopic retrograde cholangiopancreatography (ERCP), an invasive procedure that combines endoscopy and x-ray to treat issues with the bile and pancreatic ducts, carries a two to ten percent risk of causing post-ERCP pancreatitis (PEP) [1]. Because acute pancreatitis is a devastating inflammatory condition that leads to extensive morbidity and mortality, efforts to reduce the risk of PEP in patients undergoing ERCP would enhance patient outcomes and would decrease the economic burden in treating PEP nationwide [2-4].

A difficult cannulation has been identified as one of the high risk factors for developing PEP [5]. A study performed by Scandinavian Association for Digestive Endoscopy (SADE) determined that cannulations with five or more attempts, a duration of five minutes or longer, or two or more unintended pancreatic duct (PD) wire passages significantly increased one's risk for PEP [6]. Thus, SADE defined a difficult cannulation as any cannulation with at least one of the following conditions: five or more attempts, five or more minutes, or two or more unintended PD wire passages [6]. This classification of a difficult cannulation has been adopted and standardized by the European Society of Gastrointestinal Endoscopy [7]. Because no current guidelines defining a difficult cannulation exist from the American College of Gastroenterology or American Gastroenterological Association, the European Society of Gastrointestinal Endoscopy (ESGE) guidelines as gathered from the SADE study are the worldwide standardized definition of difficult cannulation.

Difficult cannulations have been reported to occur at a frequency of 42 percent for all ERCP exams [8]. The morphology and accessibility of the papilla influence the level of difficulty. Some studies have indicated that different macroscopic appearances of the papilla result in varying cannulation difficulty levels. Based on a study gauging intraobserver and interobserver agreement to the macroscopic appearance of different papillae, papillae are categorized as: Type 1, normal appearing; Type 2, small; Type 3, protruding or pendulous; and Type 4, ridged or creased [9]. Haraldsson et al. found that Type 2 and Type 3 papillae were more difficult to cannulate [8]. Regardless of papilla type, the involvement of a trainee (a GI fellow) resulted in more difficult cannulations [8]. In addition, the presence of redundant tissue, such as periampullary diverticula-which occurs in up to 20 percent of patients undergoing ERCP-results in more challenging cannulations [10]. The use of a forceps to assist in the cannulation is a demonstrated effective technique for cannulating papillae that are difficult to access [10-12]. The forceps clears the redundant tissue to enable access to the papilla, as well as stabilizes the ampullary position to permit an easier cannulation [10]. Currently, no randomized controlled trials that detail to what extent a forceps facilitates cannulation exist. Thus, our study aims to determine whether a forceps assisted cannulation reduces the incidence of difficult cannulations and consequently PEP.

The primary outcome is difficult cannulation after randomization. A difficult cannulation will be defined as any cannulation that results in any of the following: 5 or more minutes, 5 or more cannulation attempts, or 2 or more unintentional pancreatic wire passages.

The secondary outcome is PEP. Acute pancreatitis according to the Atlanta guidelines, is at least two of the following: abdominal pain consistent with pancreatitis, lipase or amylase greater than 3 times the upper limit of normal, radiographic evidence of pancreatitis on cross sectional imaging [13].