INTRODUCTION — Endoscopic retrograde cholangiopancreatography (ERCP) is an advanced endoscopic procedure that is most often used for biliary interventions (eg, removal of bile duct stones, relief of biliary obstruction, closure of bile leaks). During the procedure, a specialized, side-viewing upper endoscope is used to visualize the ampulla of Vater, followed by accessing the common bile duct with selective biliary cannulation. The bile duct is opacified by injecting a contrast medium, thereby permitting radiographic visualization and therapeutic interventions.
During some ERCPs, difficult biliary access occurs when attempts to cannulate the bile duct are unsuccessful, and this may contribute to an increased risk of ERCP-related adverse events (eg, pancreatitis) and require repeat intervention. Specialized techniques may be used to overcome difficult biliary access, but they are typically more complex than standard, guidewire-assisted cannulation and require additional training.
This topic will discuss techniques and general principles for managing difficult biliary access during ERCP in adults who do not have surgically altered anatomy.
Gastrointestinal endoscopy including ERCP in patients with surgically altered anatomy is presented separately:
●(See "Endoscopic retrograde cholangiopancreatography (ERCP) after Billroth II reconstruction".)
●(See "ERCP in patients with Roux-en-Y anatomy".)
●(See "Gastrointestinal endoscopy in patients who have undergone bariatric surgery".)
The following ERCP-related issues are also presented separately:
●Overview of ERCP indications, patient preparation, and postprocedure care – (See "Overview of endoscopic retrograde cholangiopancreatography (ERCP) in adults".)
●Standard biliary cannulation followed by sphincterotomy – (See "Endoscopic biliary sphincterotomy".)
●ERCP-related adverse events – (See "Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis" and "Post-endoscopic retrograde cholangiopancreatography (ERCP) bleeding" and "Post-ERCP perforation".)
GENERAL PRINCIPLES
Definition of difficult biliary access — Difficult biliary access (or difficult biliary cannulation) during ERCP has been defined as the inability to cannulate the common bile duct using standard, guidewire-assisted technique within 5 to 10 minutes or up to five attempts [1-3]. However, the definition of difficult access has varied among studies, and whether it is widely applied in clinical practice is uncertain.
Incidence and risk factors — The reported incidence of difficult biliary access during ERCP ranges from 4 to 20 percent among patients with normal anatomy (ie, native ampulla and no duodenal diverticulum) [2,4-6]. A biliary cannulation rate of 90 percent is generally regarded as the threshold for standard of practice [4,7]. In a systematic review of four studies including 567 patients who had ERCP with guidewire-assisted cannulation technique, the pooled rate of unsuccessful biliary cannulation was 11 percent [5]. However, rates of difficult and failed cannulation vary substantially among centers and endoscopists. While success rates for biliary access among community practices are expected to exceed 90 percent, the rates of biliary access during the index ERCP typically exceed 95 percent at advanced centers by using multiple techniques [6,8-12].
Studies on risk factors for difficult biliary access are limited. In a study including 545 patients who had ERCP with biliary sphincterotomy, advanced cannulation techniques were used in 173 patients (31 percent), and risk factors for use of needle-knife or other methods included ampullary malignancy, papillary anatomic abnormality, and duodenal stenosis [13].
Endoscopist skill and experience — The advanced cannulation methods that are described below should be used by endoscopists who achieve selective biliary cannulation in >80 percent of patients using standard techniques, consistent with society guidelines [1,3]. Advanced biliary cannulation methods require endoscopic expertise and experience. There is possibly no endoscopic intervention that requires more precision than the needle-knife method. (See 'Needle-knife access methods' below.)
When to ask for assistance or refer — For most patients undergoing ERCP, standard guidewire-assisted cannulation is successful for establishing biliary access. (See 'Incidence and risk factors' above.)
However, when biliary access is challenging, endoscopists should weigh their own likelihood of success using advanced methods and the urgency of the procedure against the risk of adverse events. If additional endoscopic expertise is available, one may call a more experienced colleague to assist with the ERCP or to perform an alternative approach such as endoscopic ultrasound-guided access. Other options include stopping the procedure and referring the patient to a second endoscopist or to a specialized center for repeat ERCP or for an alternative approach such as endoscopic ultrasound or percutaneous transhepatic cholangiography. (See 'Non-ERCP options for biliary access' below.)
ERCP-GUIDED ADVANCED CANNULATION
Goals — For patients with difficult biliary access, the goals of using advanced cannulation methods are to establish biliary access for therapy (eg, stone removal, stent placement, closure of bile leak) while minimizing the risk of adverse events. Achieving the optimal balance between technical success and adverse events requires attention to the individual patient's underlying condition and risk profile, as well as the endoscopist's expertise. As techniques and supporting data evolve, endoscopists are advised to refine and update their approaches. Educational materials including video instruction are available online at the American Society of Gastrointestinal Endoscopy [14].
The use of advanced cannulation methods is essentially limited to therapeutic procedures because other options for diagnostic assessment (eg, magnetic resonance cholangiopancreatography [MRCP] and endoscopic ultrasound) provide high diagnostic accuracy without the risks associated with ERCP. (See "Overview of endoscopic retrograde cholangiopancreatography (ERCP) in adults", section on 'Indications'.)
Selecting an advanced cannulation method — Based on published data and clinical experience, we use a risk-stratified approach for establishing biliary access that involves tailoring techniques to the individual patient and switching expeditiously to an advanced cannulation technique when standard technique is not successful (algorithm 1) [1-3,15,16].
There are multiple techniques available for achieving biliary access [1-3,12,14,17]. The balance between success and adverse events varies between patients as well as endoscopists. Put simply, what is safe in one patient may not be tolerated in another due to patient-related and anatomic characteristics (table 1) [18-23]. (See "Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis", section on 'Risk factors'.)
The choice of a rescue method is also informed by the endoscope position and stability, whether there has been guidewire insertion into the pancreatic duct, and efficacy/safety of advanced cannulation methods.
Specific advanced cannulation techniques
Pancreatic guidewire- and stent-assisted techniques — The pancreatic guidewire technique (also referred to as double guidewire technique) involves leaving the guidewire in the pancreatic duct and using it to facilitate cannulating the common bile duct with a second guidewire (picture 1). We typically place a pancreatic stent after achieving biliary access because use of double guidewire technique without subsequent pancreatic stent placement increases the risk of post-ERCP pancreatitis [15,24]. In a trial including 70 patients who underwent ERCP with pancreatic guidewire technique for achieving biliary cannulation, pancreatic stenting reduced the rates of post-ERCP pancreatitis compared with no stenting (3 versus 23 percent) [25].
In addition, society guidelines support placing a pancreatic stent after dual wire cannulation [3,20,22,23].
Our approach to pancreatic guidewire technique is summarized as follows:
●Leave the guidewire in the pancreatic duct and place a sphincterotome or ultra-tapered 5-4-3 catheter above it. The pancreatic guidewire helps to straighten the S-shaped portion of the distal common bile duct and stabilize the papilla.
●Advance a second guidewire through a sphincterotome, or ultra-tapered 5-4-3 catheter, to selectively cannulate the bile duct, with attention to false passages.
●Place a pancreatic stent prior to withdrawing the pancreatic guidewire, unless the patient has a completely obstructed pancreatic duct, or otherwise is at very low risk for post-ERCP pancreatitis.
●Perform sphincterotomy or other interventions as required.
A modification of the pancreatic guidewire technique is to place a pancreatic stent into the pancreatic duct, followed by biliary cannulation over the stent [26]. We use this technique sparingly in patients with a stenotic papilla, as it can "crowd out" the sphincter and make biliary access more difficult. As an example, in a study including 100 patients with difficult biliary access, rates of unsuccessful cannulation prompting use of a needle-knife rescue method were higher with wire-guided cannulation over a pancreatic stent compared with double wire technique (46 versus 10 percent) [27].
Transpancreatic precut sphincterotomy — Transpancreatic precut sphincterotomy (also referred to as transpancreatic septotomy or transpancreatic precut papillotomy) is typically an option for patients with difficult biliary access when a guidewire is inadvertently and repeatedly passed into the pancreatic duct, and this technique does not require the use of a needle-knife (picture 2).
We agree with society guidelines that transpancreatic precut sphincterotomy may be preferred in selected patients (ie, those with an intradiverticular or small papilla) because it may be associated with lower risk of adverse events than other precut techniques when the papilla is distorted by tumor or other factors [20]. Although limited observational data suggested favorable long-term outcomes after transpancreatic precut sphincterotomy [28], we generally avoid this technique in younger patients and in those with a normal pancreas and/or small pancreatic ducts because of the potential for stricturing of the pancreatic sphincter or duct.
The technique for transpancreatic precut sphincterotomy is summarized as follows [16,29]:
●Leave (or introduce) an insulated guidewire into the pancreatic duct.
●Advance the nose of a pull-type sphincterotome into the distal portion of the pancreatic duct.
●Direct the cutting wire of the sphincterotome toward the center of the papillary mound, where the bile duct almost always sits, to expose the common bile duct by opening the septum between the pancreatic and bile ducts.
●If a pancreatic stent is to be placed, leave a pancreatic guidewire in place while probing for the bile duct with a wire-guided papillotome or catheter. Place the pancreatic stent before continuing with biliary therapy.
In agreement with society guidelines, we place a pancreatic stent for most patients undergoing transpancreatic precut sphincterotomy, except for patients at very low risk of pancreatitis (eg, those with malignant obstruction of the pancreatic duct) [20].
Data from observational studies and randomized trials suggested that transpancreatic precut sphincterotomy technique was effective without increasing the risk of adverse events [15,28-33]. However, data are limited because most studies included patients at low or average risk of post-ERCP pancreatitis and inconsistently utilized pancreatic stenting. In a cohort study including 369 patients with difficult biliary access who underwent transpancreatic precut sphincterotomy, cannulation was successful in 321 patients (87 percent) [29]. Adverse event rates were not significantly different for patients who had transpancreatic precut sphincterotomy compared with a control group undergoing ERCP (4 versus 3 percent).
Needle-knife access methods — For patients with difficult biliary access, we typically use precut needle-knife methods relatively early in the procedure (ie, within 5 to 10 minutes or after a few cannulation attempts) for patients with a bulging papilla from an impacted common bile duct stone or other cause.
We may also use a needle-knife method for patients in whom pancreatic guidewire technique was unsuccessful. When pancreatic instrumentation such as deep pancreatic guidewire insertion has occurred, we place a pancreatic stent prior to using a needle-knife method, and this approach is consistent with society guidelines [3,22,23]. The pancreatic stent remains in place at the conclusion of the procedure because immediate removal has been associated with increased risk of pancreatitis. (See 'Pancreatic stenting' below.)
Equipment — Equipment for performing needle-knife technique includes a needle-knife papillotome, which is a catheter with a thin-wire cutting needle at its distal end. The equipment used for standard, guidewire-assisted biliary cannulation and endoscopic sphincterotomy (eg, sphincterotomes, guidewires, electrosurgical devices) is discussed separately. (See "Endoscopic biliary sphincterotomy", section on 'Equipment'.)
Techniques — Selecting a specific needle-knife technique is individualized and informed by anatomic factors (eg, bulging papilla versus a flat or smaller papilla) and endoscopist experience. Techniques for using a needle-knife to facilitate biliary access are summarized as follows:
●Needle-knife fistulotomy – For needle-knife fistulotomy (also referred to as fistulotomy), the needle-knife papillotome punctures the papilla above the orifice and then cuts either downward toward the papillary orifice or upward in a cephalad direction until the biliary sphincter is visualized (figure 1) [3,13,34]. We generally reserve this technique for patients with a bulging papilla in whom the pancreatic duct has not been accessed. Such a technique usually avoids contact with the pancreatic orifice and may reduce the risk of post-ERCP pancreatitis [35]. However, it may not be technically feasible or safe in patients with a smaller or nonbulging papilla [3].
●Free-hand needle-knife papillotomy (from the orifice) – Needle-knife papillotomy (NKP; also referred to as needle-knife precut papillotomy [NKPP]), involves making an incision with the needle-knife starting at the upper margin of the papillary orifice and extending cephalad (ie, in the direction of the bile duct) (figure 2). NKP is typically followed by biliary sphincterotomy, which facilitates interventions such as stone extraction. Thus, the terms "access papillotomy," "access sphincterotomy," or "precut sphincterotomy" have also been used to describe this method. We typically use this technique for patients with a nonbulging papilla in whom the pancreatic duct has not been accessed. Needle-knife papillotomy should be used with extreme caution when initiating the papillary orifice incision. In addition, use of this technique is generally limited to patients with well-defined anatomic landmarks and by experienced advanced endoscopists.
We visualize the papillary orifice and insert 2 to 5 mm of cutting wire. We raise the elevator to "load" the cutting wire upwards and aim to the center of the papillary mound, which is typically located in the 11 to 12 o'clock direction but can vary depending on the endoscope position. We also ensure that the tip of the needle is just under the roof of the papilla and not impacted against the duodenal wall or the orifice of the pancreatic duct. The cut is continued in small increments, exposing deeper or high layers, somewhat akin to the layers of an onion, until either the biliary sphincter muscle is exposed, which often appears as a "nipple," or there is some bile seepage. We then gently probe the suspected bile duct with a wire-assisted papillotome or ultra-tapered catheter to gain access. Once access is established, the sphincterotomy is usually completed with a conventional, pull-type papillotome. If access is not obtained after gentle probing, the needle-knife can be used to unroof more of the papilla, once again beginning at the orifice and advancing through the previously cut area to expose deeper layers.
●Needle-knife over a pancreatic stent – If the pancreatic duct has been deeply accessed with a wire during cannulation attempts, a variation of the needle-knife technique is to place a protective pancreatic stent prior to performing the incision (figure 3). This technique allows for protection of the pancreatic duct, especially when the anatomy of the ducts within the major papilla is atypical. Otherwise, the technique is similar to freehand needle-knife as described above [36,37]. The pancreatic stent remains in place at the end of the procedure as immediate removal has been associated with higher risk of pancreatitis [37]. (See 'Pancreatic stenting' below.)
Efficacy — Data from observational studies and randomized trials suggested that initial cannulation success after needle-knife techniques have ranged from 50 to over 90 percent, with wide variability of success and adverse events according to endoscopist expertise, as well as patient selection [15,38-41].
PANCREATIC STENTING
Goals — The goals of pancreatic stent placement during ERCP with difficult bile duct access are to establish pancreatic drainage, relieve intraductal pressure from papillary edema, and in some cases, to provide anatomic guidance while the papilla is dissected. Pancreatic stenting lowers the risk of post-ERCP pancreatitis of any severity [22,23].
Indications — For patients with difficult biliary access, the decision to place a pancreatic stent is individualized and should factor in patient- and procedure-related risk factors for post-ERCP pancreatitis (table 1), technical factors encountered during the procedure, risk of adverse events with stenting, and endoscopist expertise. We typically place a pancreatic stent to reduce the risk of post-ERCP pancreatitis for patients with any of the following conditions, and this approach is supported by society guidelines [3,20,22,23] (see 'ERCP-guided advanced cannulation' above):
●Deep or repeated pancreatic guidewire insertion in the absence of a completely obstructed pancreatic duct.
●Intentional placement of a guidewire into the pancreatic duct to facilitate biliary cannulation (ie, pancreatic guidewire-assisted biliary cannulation).
●Prior to needle-knife precut if the pancreatic duct was accessed with a guidewire.
●Following transpancreatic precut sphincterotomy.
Although pancreatic stent placement may occur before or after biliary therapy, we place the pancreatic stent before removing the pancreatic guidewire because it may be difficult or impossible to access the pancreatic duct at the end of the procedure.
Technique — Pancreatic stents are available in multiple configurations and materials. Thus, selecting a stent size and configuration is generally informed by patient and duct characteristics (eg, ductal anatomy).
For most patients with difficult biliary access, we use a small caliber (ie, 4 or 5 French) plastic stent. When the wire is easily advanced into the pancreatic duct and beyond the genu of the pancreas, we usually place a smaller caliber (4 French), longer (eg, 9 to 11 cm) soft plastic, unflanged stent with a single external pigtail.
If the wire cannot be passed easily beyond a tight turn or the genu of the pancreas, an alternative is to pass a small caliber (0.018 to 0.025 inch) wire and then place a short (2 to 3 cm) stent [42]. If a patient is at high risk of post-ERCP pancreatitis, we may choose an inner retention flange on a shorter stent to avoid premature stent migration. However, we do not place stents with lengths between 4 to 7 cm or stents made of rigid polyethylene material in such patients because these stents typically impact into the genu and may cause strictures.
Stent removal — We obtain a plain film in three to four weeks after pancreatic stent placement to document spontaneous stent passage. If the stent remains in place, we remove it by performing upper endoscopy.
Efficacy — Data from numerous randomized clinical trials indicated that placement of a pancreatic stent reduced the risk of post-ERCP pancreatitis of any severity [22,23,36,37]. In a meta-analysis of 17 trials including 2595 high-risk patients undergoing ERCP, pancreatic stents reduced the overall risk of post-ERCP pancreatitis by 65 percent compared with no stent (0 versus 1 percent; OR 0.35, 95% CI 0.26-0.46) [23]. Pancreatic stent placement also resulted in lower risk of moderately severe pancreatitis (OR 0.38, 95% CI 0.23-0.63) and lower risk of severe pancreatitis (OR 0.20, 95% CI 0.06-0.65).
Despite multiple guidelines and data endorsing the benefits of pancreatic stenting, some studies suggested that use of stent placement for prophylaxis has been declining over time while the incidence, severity, and mortality related to post-ERCP pancreatitis have been increasing [43-47]. Additional strategies for reducing the risk of post-ERCP pancreatitis including pharmacologic prophylaxis are discussed in more detail separately. (See "Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis", section on 'Preventive strategies'.)
Attempts to place a pancreatic stent in patients with difficult biliary access may involve technical challenges resulting in unsuccessful placement, which increases the risk of post-ERCP pancreatitis [42,48]. Other potential adverse events include inward stent migration and ductal injury, especially with larger caliber stents. (See "Pancreatic stenting at endoscopic retrograde cholangiopancreatography (ERCP): Indications, techniques, and complications", section on 'Adverse events'.)
ADVERSE EVENTS — The types of adverse events associated with advanced access methods are similar to those reported with standard cannulation techniques and include the following (see "Endoscopic biliary sphincterotomy", section on 'Complications'):
●Post-ERCP pancreatitis – In multicenter cohort studies involving a spectrum of endoscopists and patients, precut techniques have been associated with increased risk of post-ERCP pancreatitis and other adverse events. However, it remains uncertain whether increased risk for adverse events is related to the precut technique itself or to prior multiple attempts to cannulate the bile duct. In contrast, data from specialized centers with experienced endoscopists suggested that needle-knife access technique was not associated with increased risk of post-ERCP pancreatitis [15,35,39,49,50]. In a meta-analysis of six trials including 853 patients, early use of needle-knife techniques resulted in lower risk of post-ERCP pancreatitis compared with repeated attempts at standard cannulation (5 versus 11 percent, risk ratio [RR] 0.55, 95% CI 0.31-0.97) [15].
Studies suggested that guidewire-assisted cannulation was more effective and safer than catheter-guided cannulation followed by contrast injection [1-3,17]. However, a common misconception is that avoiding pancreatic contrast injection per se prevents post-ERCP pancreatitis, especially in patients with multiple risk factors (table 1). Although pancreatic contrast injection poses a risk, there are multiple other patient- and procedure-related risk factors that are additive or even synergistic [18-23]. Passing a guidewire into the pancreatic duct is a significant risk factor, independent of contrast injection. Studies have found that deep pancreatic wire passage resulted in equal or greater risk compared with contrast injection, unless guidewire passage is followed by pancreatic stent placement [19-23]. In a multivariate analysis of 800 patients with intact papilla undergoing ERCP with guidewire cannulation, pancreatic wire passage was associated with increased risk of post-ERCP pancreatitis, whereas pancreatic contrast injection was not a risk factor [21].
When attempting cannulation with the wire-guided technique, an additional risk of "blind" wire passage is inadvertent perforation of the pancreatic duct or its side branches, which can result in severe and potentially necrotizing pancreatitis. Such a risk is likely greatest in patients with a normal, healthy pancreas and those with a tortuous pancreatic duct. When performed appropriately, pancreatic stenting minimizes the risk of deep pancreatic guidewire passage. (See 'Pancreatic stenting' above.)
●Other adverse events – Studies have suggested that advanced access techniques were not associated with higher risk of other adverse events such as perforation, cholangitis, and bleeding [15,50]. In a meta-analysis of seven trials including 1032 patients who underwent ERCP, the risk of perforation, cholangitis, or bleeding was not significantly different between patients who had ERCP with needle-knife access method compared with repeated standard cannulation attempts [50].
Although these data are promising, rates of adverse events may be higher when advanced techniques are performed by less experienced endoscopists [34,42,51]. In addition, studies comparing advanced techniques with standard cannulation are limited by variable definitions of adverse events (eg, criteria for post-ERCP pancreatitis), patient characteristics (eg, anatomy, underlying disease), and individual variations of the techniques.
Thus, it has been recognized that use of advanced techniques such as needle-knife precut papillotomy by less experienced endoscopists or in patients with altered anatomy or uncertain indications may be complicated by perforation, severe pancreatitis, and/or bleeding [51]. Factors informing the selection of an advanced cannulation method are discussed above. (See 'Selecting an advanced cannulation method' above.)
POST-PROCEDURE CARE — Post-procedure care following ERCP includes monitoring patients as they recover from anesthesia. Post-anesthesia care and other post-procedure issues are discussed in more detail separately. (See "Overview of endoscopic retrograde cholangiopancreatography (ERCP) in adults", section on 'Post-procedure care' and "Anesthesia for gastrointestinal endoscopy in adults", section on 'Post-anesthesia care'.)
We monitor patients who required advanced cannulation techniques for symptoms and/or signs of adverse events (eg, new or worsening abdominal pain, fever). For patients at high risk of post-ERCP pancreatitis (table 1), we measure amylase and lipase levels two to three hours after the procedure because these levels may predict the development of pancreatitis. If amylase or lipase are greater than two to three the upper limit of normal and the patient develops abdominal pain or tenderness after the procedure, we observe the patient in the hospital overnight because promptly recognizing post-ERCP pancreatitis or perforation has been associated with better outcomes [52,53].
Management of suspected post-ERCP pancreatitis is discussed in detail separately. (See "Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis".)
NON-ERCP OPTIONS FOR BILIARY ACCESS — For patients with difficult biliary access in whom ERCP-guided access methods are not successful, alternatives to ERCP include:
●Percutaneous transhepatic cholangiography – Percutaneous transhepatic puncture of the bile duct is an option for achieving biliary access in patients with biliary tract dilatation related to biliary obstruction. During percutaneous transhepatic cholangiography (PTC), the interventional radiologist inserts a small-gauge needle into the peripheral bile ducts, followed by injection of contrast material to opacify the biliary tree. When biliary drainage is indicated, an external catheter or an internal stent may be placed. An alternative to imaging-guided stent placement is percutaneous introduction of a guidewire into the duodenum, followed by a rendezvous endoscopic procedure. ERCP requiring percutaneous biliary access is associated with increased risk of adverse events but may be the only option for some patients [39]. Clinical applications and technique of PTC are discussed in more detail separately. (See "Percutaneous transhepatic cholangiography in adults".)
●Endoscopic ultrasound (EUS)-guided biliary rendezvous – For patients in whom biliary access is unsuccessful with ERCP alone, and especially for those with obstructing duodenal or ampullary lesions, EUS-guided rendezvous or direct biliary drainage is an alternative method for gaining access to the bile ducts. In contrast to percutaneous transhepatic biliary drainage, EUS-guided rendezvous can be performed immediately following the unsuccessful ERCP [54,55]. The left intrahepatic ducts, common bile duct, and main pancreatic duct are well visualized with EUS and can be accessed with either a transgastric or transduodenal approach. Therapeutic EUS is discussed separately. (See "Therapeutic endoscopic ultrasound", section on 'EUS-guided cholangiopancreatography'.)
SUMMARY AND RECOMMENDATIONS
●Background – Difficult biliary access during endoscopic retrograde cholangiopancreatography (ERCP) is typically defined as the inability to cannulate the common bile duct using standard, guidewire-assisted technique within 5 to 10 minutes or up to five attempts. (See 'Definition of difficult biliary access' above.)
●ERCP-guided advanced cannulation methods
•Goals – The goals of using an advanced cannulation method are to establish biliary access and provide biliary therapy (eg, stone removal, biliary drainage) while minimizing the risk of adverse events. In general, we use a rapid succession of techniques rather than persistent cannulation attempts with standard techniques. The use of advanced cannulation techniques should be limited to therapeutic procedures because noninvasive diagnostic testing (eg, magnetic resonance cholangiopancreatography) provides high diagnostic accuracy without the risks associated with ERCP. (See 'Goals' above.)
•Selecting a method – When standard cannulation attempts are not successful, the choice of a rescue method is generally informed by multiple factors including patient characteristics (eg, indications for the procedure, anatomy, and risk profile), endoscope position, wire passage into the pancreatic duct, efficacy/safety of advanced cannulation methods, and endoscopist expertise with individual approaches (algorithm 1). (See 'Selecting an advanced cannulation method' above and 'Non-ERCP options for biliary access' above.)
•Options – Principal options for advanced biliary cannulation include:
-Pancreatic guidewire method (also referred to as double guidewire method) (see 'Pancreatic guidewire- and stent-assisted techniques' above)
-Needle-knife access methods (ie, needle-knife fistulotomy, needle-knife papillotomy) (see 'Needle-knife access methods' above)
-Transpancreatic precut sphincterotomy (see 'Transpancreatic precut sphincterotomy' above)
●Pancreatic stenting – For patients with difficult biliary access, the decision to place a pancreatic stent is individualized and informed by patient risk factors for post-ERCP pancreatitis (table 1), technical factors encountered during the procedure, risk of adverse events with stenting, and endoscopist expertise.
For patients in whom the pancreatic duct was manipulated with a guidewire, we recommend placement of a pancreatic stent (Grade 1B) since stenting lowers the risk of post-ERCP pancreatitis. We typically place a small caliber (ie, 4 or 5 French) plastic stent and document spontaneous passage with a radiograph in three to four weeks. (See 'Pancreatic stenting' above.)
●Post-procedure care – Post-procedure care following ERCP includes careful monitoring of patients as they recover from anesthesia. We monitor all patients for symptoms of adverse events (eg, new or worsening abdominal pain, fever). For patients with multiple risk factors for post-ERCP pancreatitis (table 1), we measure amylase and lipase levels two to three hours after the procedure.
Post-anesthesia care and other post-procedure issues are discussed in more detail separately. (See "Overview of endoscopic retrograde cholangiopancreatography (ERCP) in adults", section on 'Post-procedure care' and "Anesthesia for gastrointestinal endoscopy in adults", section on 'Post-anesthesia care'.)
●Adverse events – The types of adverse events associated with advanced access methods are similar to those reported with standard cannulation techniques and include pancreatitis, bleeding, and perforation. (See 'Adverse events' above.)
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