Can Prophylactic Pancreatic Duct Stent Placement Reduce the Prevalence of Post-ERCP Pancreatitis in Patients with Difficult Cannulation of the Bile Duct?

Abstract

Background and Aim: Pancreatitis remains a major complication of ERCP. Difficult cannulation of the bile duct is given as its risk factor. The aim of this study was to investigate the efficacy of prophylactic pancreatic duct stent placement in patients at high risk of post-ERCP pancreatitis. Patients and methods: Between July 2002 and July 2006, prophylactic pancreatic duct stenting were performed in 44 patients (20 men, 24 women; mean age, 69 yr; range, 44-91 yr) at high risk of post-ERCP pancreatitis. We developed a new pancreatic duct stent, which was a 5-Fr, 4-cm-long stent with a single duodenal pigtail (Pit-stent: Cathex, Co., Ltd., Tokyo, Japan). The Pit-stent employed is made of soft polyethylene without a flange and has side-holes for avoiding blockage of side branches of the pancreas. Indication for pancreatic duct stenting was difficult cannulation of the bile duct. Difficult cannulation of the bile duct was defined as which took more than 15 minutes. Abdominal radiographs were obtained to assess the stent position 2-14 days after the procedure. The frequency of post-ERCP pancreatitis and spontaneous migration of the stent were investigated. A diagnosis of post-ERCP pancreatitis was defined according to Cotton's criteria. Results: Pancreatic duct stent placement was successfully performed in 90% of the patients. Of 40 patients who successfully underwent stent placement, one patient developed mild pancreatitis (2.5%). Of four patients who failed stent placement, two patients developed mild pancreatitis (50%). Of the 35 patients with normal serum amylase level before the procedure, hyperamylasemia at 24 h after ERCP was observed in 60% (21 patients). Of these patients, the onset of an increase in the level of amylase was seen in 66% (14 patients) at 3 h, in 10% (2) at 6 h, and in 24% (5) at 24 h after ERCP. One patient who developed pancreatitis after ERCP manifested elevation of amylase level at 3 h after ERCP followed by a further increase at 6 h. The decrease of serum amylase level was observed at 48-72 h after ERCP in all patients associated with hyperamylasemia. Spontaneous migration of the stent was observed in 91% within one month (mean duration, 8 days). There were no other complications or procedure-related deaths. Conclusions: Pancreatic duct stent insertion can reduce the incidence of post-ERCP pancreatitis in patients with difficult cannulation of the bile duct. Spontaneous migration of a pancreatic stent that contributes to lessening of the need for additional ERCP can be expected with the use of a Pit-stent.