Complications of prophylactic pancreatic stenting used for the prevention of post-ERCP pancreatitis with regards to stent types: Results of a prospective, controlled study

Introduction: Post-ERCP pancreatitis (PEP) is the most common complication of ERCP, which can be severe and life threatening especially in high risk patients. Prophylactic pancreatic stent (PPS) insertion is suggested to prevent PEP. Although it is a safe procedure a few complications have been described. The aim of the study was to analyze these in terms of stent types in our prospectively collected database.

Patients and methods: 317 patients with high risk of PEP were considered for PPS placement over the past 5 years. PEP was categorized as mild, moderate and severe according to the Cotton consensus criteria. Three different types of 5 Fr, 3 – 5 cm long PPSs were used (straight with or without internal flap, and Freeman type stent (FTS) with internal flap and outer pigtail end). Complications such as unsuccessful PPS insertion, early stent dislodgement and proximal migration were identified.

Results: PPS insertion was unsuccessful in 29 patients (9.15%). PEP developed in 41.38% of these patients (n = 12; 7 mild, 4 moderate, 1 severe) compared to 10.07% of the 288 successfully stented patients (n = 29; 24 mild, 4 moderate, 1 severe). The complications rate was 2.78% (n = 8) in the successfully stented group. We found early stent dislodgement in 5 patients (2 stents without internal flaps, 3 FTSs), who all developed mild PEP. Of the 3 patients who received FTS 1 had severe postpapillotomy bleeding one day after the ERCP, while the other 2 had papillary balloon dilation which might have contributed to early stent dislodgement. Proximal stent migration into the pancreatic duct occurred in 3 patients, all inserted stents were straight with internal flaps. Stent extraction was possible in 2 patients, while it was unsuccessful twice in 1 patient, who finally underwent distal pancreatectomy. We did not observe this complication since the introduction of FTSs into our practice. Although it has been described earlier we have not observed pancreatitis due to stent removal.

Discussion: PPS insertion is a safe method however compications may occur. The most severe is proximal stent migration, which may lead to surgery in minority of cases when endoscopic removal remains unsuccessful. The use of FTS might prevent this complication. Other complications are mild and can be managed conservatively.