We searched our prospectively maintained ERCP database for patients who underwent transpancreatic sphincterotomy(TPS) or needle knife fistulotomy(NKF) for difficult biliary access in National Taiwan University Hospital from October 2015 to October 2017. We retrieved patient characteristics including gender, age, and indication of ERCP. Procedural information was also collected, such as endoscopic findings, total number of pancreatic duct cannulations, post-cannulation procedures and measures for PEP prophylaxis. Finally, we recorded the success rate as the primary outcome and adverse events of the patients as the secondary outcome by following up the patients’ clinical condition and blood tests such as levels of hemoglobin, serum total bilirubin and amylase/lipase.
All the procedure during the study period were performed by five experienced endoscopists, who performed more than 100 therapeutic ERCP per year. Endoscopic retrograde cholangiopancreaticography and further intervention were performed with a standard side-view duodenoscope (TJF260, Olympus, Tokyo, Japan). The bile duct cannulation was attempted firstly with catheter with a inserted guidewire. When encountering a difficult biliary access, which refers to more than five contacts with papilla or more than ten minutes of cannulation with failure, endoscopists may choose TPS, NKF or double guidewire as salvage method for achieving successful biliary access by their clinical judgement. In patient undergoing TPS, TPS was performed as Goff reported ; in short, after cannulation of the pancreatic duct was achieved, a triple-lumen sphincterotome (V KD-V411M-0730, Olympus, Tokyo, Japan or TRUEtome cut wire 4.4F x 30mm (Boston Scientific Taiwan, Taipei, Taiwan) on a guidewire was used to cut the septum between bile and pancreatic ducts along the direction of 11 o’clock to 12 o’clock. After this, the sphincterotomy was extended to expose the biliary lumen and the biliary duct could be cannulated. In patient with NKF, a needle-knife with MicroKnife XL 5.5F (Boston Scientific Taiwan, Taipei, Taiwan) and an ERBE electrosurgical generator were used to perform a stepwise incision of the mucosa above the papillary orifice followed by downward cut until the underlying biliary sphincter was visualized. Choice of TPS or NKF and PEP prophylaxis depended on endoscopists’ judgement, and there was no definite or consensual strategies for difficult biliary cannulation among endoscopists.
Definitions of Complications
We followed the definition of post-ERCP pancreatitis(PEP) according to a consensus from Cotton et all., which was originally defined as “clinical pancreatitis with amylase at least three times normal at more than 24 hours after the procedure, requiring hospital admission or a prolongation of planned admission”. The definition of significant post-ERCP hemorrhage was defined as clinical (not just endoscopic) evidence of bleeding such as melena or hematemesis according to the same consensus . We also record post-ERCP hemorrhage judged by endoscopy as “endoscopically bleeding”. Perforation was referred to as document by any radiographic studies. Cholangitis was defined as fever with temperature more than 38 ° C because of biliary source without evidence of other concomitant infections.
Statistical analyses were performed using Stata 13.0 software (Stata Corp LP, College Station, TX, United States). Statistical analysis was performed using chi-squared tests for categorical data and the Student’s t test for continuous data. Mann-Whitney U test was used for post- and pre-ERCP amylase/lipase levels and number of pancreatic duct cannulation. P value of < 0.05 was regarded as statistically significant. Univariable analyses were performed to assess the outcomes and adverse events of ERCP in patients who underwent TPS or NKF. We also used multivariable logistic regression to assess the association between PEP and TPS or NKF while adjusting for age, gender, number of pancreatic duct cannulation, endoscopic papillary balloon dilatation (EPBD) and PEP prophylaxis.