Aims Around 11% of Endoscopic retrograde cholangiopancreatography (ERCP) associate difficult
cannulation [1]. We aimed to extract real world data on difficult cannulation over a 3-year period
to assess if the outcomes were comparable to the reported literature on cannulation
success rate and adverse events.
Methods A retrospective study was conducted from September 2020 to January 2024 at a high
volume centre. All patients who underwent ERCP by a single independent ERCPist were
included in the analysis. Primary outcomes were rate of first pass cannulation, advanced
techniques performance, adverse events (AEs) including 30-day mortality [2]
[3]
[4]
[5]
[6].
Results A total of 438 patients underwent ERCP by the operator during the study period. Cannulaion
was achieved in 389 (88.9%). Of these patients, first pass cannulation was achieved
in 325/438 (74.2%) Of those who Pancreatic duct (PD) was inadvertently cannulated≥2
times, double wire was used, 36/438 (8.21%), unsuccessful in 17 (47.2%), but of this,
9 cases were salvaged -4 patients managed common bile duct (CBD) cannulation after
PD stent was placed, 3 patients had needle knife (KN) precut and 2 transpancreatic
sphincterotomy. Failed patients had etiology of biliopancreatic cancer and one had
a big duodenal diverticulum as deterrents. Needle Knife was used in 25/438 (5.7%)
of which failed in 12/25 (48%)- despite this unfavourable outcome, out of these failures,
this helped in 6 patients during the following ERCP as scarring exposed the ampullary
opening better. 4 patients were never reattempted so we cannot know if KN would have
been useful, and 2 failed in a tertiary centre. Transpancreatic sphincterotomy (TPS)
was attempted 8 times (1.82%) usually after double wire failed. This achieved cannulation
in 5/8 (62.5%). Adverse events (AEs): Of all ERCP-related AEs, double wire associated
higher risk of post-ERCP pancreatitis -OR 3.96(1.02- 15.3) p=0.04, but when stratified,
this association was only significant in those cases when prophylactic PD stent was
not placed after double wire use (all due to technical difficulty)
Conclusions When confronted with difficult cannulation, double wire succeeded 52.8% of the time.
(Variability in literature ranges from 44-80%). There was strong association to post-ERCP
pancreatitis only when prophylactic PD stent was not used. When other techniques added
to failed double wire, the total cannulation rate increased to 77.8% Precut sphincterotomy
only succeeded in 52%, much lower than described in literature (> 75%). Learning curve
and patient suboptimal tolerance likely contributed to this. Despite this, needle
knife helped in many cases to achieve cannulation another day. TPS was linked with
higher success at 62.5%. None of these two techniques statistically associated higher
pancreatitis, bleed, perforation or death compared to standard cannulation.
