Sphincter of Oddi manometry: decreased risk of clinical pancreatitis with use of a modified aspirating catheter

Endoclip papillaplasty restores sphincter of Oddi function: Pilot study

OBJECTIVES

Endoscopic sphincterotomy (EST) damaged the sphincter of Oddi (SO) function. This study aimed to explore the feasibility and efficacy of endoclip papillaplasty in restoring SO function.

METHODS

This prospective pilot study included consecutive patients with choledocholithiasis (stone size ≥10 mm) who underwent large-EST for stone removal, followed by endoclip papillaplasty, between May 2018 and March 2019.

RESULTS

Thirty patients were enrolled in this trail. Overall, 80% of the patients had a SO basal pressure of >10 mmHg after endoclip papillaplasty. Manometric parameters, including SO basal pressure, phasic wave contraction amplitude, phasic waves per minute, recovered after endoclip papillaplasty (P > 0.05). There were no significant differences in the manometric parameters of SO between healing grades A and B. Six patients developed mild post-endoscopic retrograde cholangiopancreatography pancreatitis, including three that had pancreatic stenting. Bile duct stone recurrence developed in 3.3% of the patients (1/30) during an 18-month follow-up.

CONCLUSIONS

Endoclip papillaplasty might restore SO function and possibly prevented biliary stone and cholangitis recurrence.

Risk factors of post- endoscopic retrograde cholangiopancreatography pancreatitis in biliary type sphincter of Oddi dysfunction in Japanese patients

OBJECTIVE

Suspected sphincter of Oddi dysfunction (SOD) is a well-known risk factor for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). The indication of ERCP for suspected SOD patients was very low in Japan compared to other countries. Therefore, the risk of PEP may be different in Japanese SOD patients. The objective of this study was to evaluate the risk of PEP in suspected biliary type SOD in Japan.

METHODS

From December 1996 to January 2017, 72 patients were suspected as having biliary type SOD, by questionnaire, liver function tests, hepatobiliary scintigraphy, abdominal ultrasonography, upper gastrointestinal endoscopy, endoscopic ultrasonography and magnetic resonance cholangiopancreatography. Finally, 60 patients who underwent ERCP were included in this study, and the factors associated with PEP were evaluated.

RESULTS

The overall PEP rate was 23.3% (n = 14). Diagnostic ERCP alone for SOD did not increase the risk of PEP. The correlation of PEP incidence with pancreatic duct guidewire (PGW) technique and endoscopic sphincterotomy (EST) was indicated in univariate and multivariate analysis. Pancreatic stent placement was a risk in univariate analysis but not in multivariate analysis.

CONCLUSIONS

PGW technique and EST for biliary type SOD were important risk factors for PEP. Pancreatic stenting was ineffective for prevention of PEP.

Role of ERCP in Patients With Idiopathic Recurrent Acute Pancreatitis

OPINION STATEMENT

Recurrent acute pancreatitis (RAP) is defined based on the occurrence of two or more episodes of acute pancreatitis. RAP is differentiated from chronic pancreatitis based on the presence of a normal morphological appearance of the pancreas between episodes. RAP can be due to a variety of etiologies including common bile duct stones or sludge, sphincter of Oddi dysfunction (SOD), pancreas divisum (PD), anomalous pancreaticobiliary junction, genetic mutations, and alcohol related. In approximately 30 % of patients, the etiology of RAP is unclear and the term "idiopathic" is used. Endoscopic retrograde cholangiopancreatography (ERCP) can be utilized in both the diagnosis and the initial management of RAP, but it has known limitations and risks. Since gallbladder sludge and SOD account for most cases with RAP, cholecystectomy and, eventually, endoscopic biliary and/or pancreatic sphincterotomy are performed as a part of management. In patients with PD-associated RAP, data from uncontrolled and primarily retrospective studies point toward a benefit from minor papillary endoscopic intervention. However, given the lack of quality data from prospective randomized controlled trials (RCTs), endoscopic management in such patients remains an individualized decision, and RCTs are needed to ascertain its true long-term benefit. Future studies to investigate the role of endoscopic therapy in preventing progression to chronic pancreatitis are needed.

Biliary tract pressure before and after endoscopic papillary balloon dilation treatment for common bile duct stones

AIM: To determine the biliary tract pressure before and after endoscopic papillary balloon dilation (EPBD) treatment for common bile duct stones.

METHODS: Clinical data for 96 patients with common bile duct stones who successfully underwent EPBD and biliary manometry from September 2011 to January 2014 were retrospectively analyzed.

RESULTS: Biliary tract pressure was significantly higher in patients with common bile duct stones than in healthy controls, which could be relieved by EPBD. Biliary tract pressure in patients who underwent cholecystectomy was higher than in patients with gallbladder stones. After operation, there were 2 cases of hyperamylasemia, 2 cases of acute pancreatitis and 2 cases of mild cholangitis, all of which resolved after non-operative treatment. The incidence of complications was 6.3% (6/96). No serious complications occurred.

CONCLUSION: EPBD treatment can effectively solve biliary obstruction and reduce biliary pressure.

Endoscopic retrograde cholangiopancreatography (ERCP)-related adverse events: post-ERCP pancreatitis

Post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP), and not uncommonly is the reason behind ERCP-related lawsuits. Patients at high risk for PEP include young women with abdominal pain, normal liver tests, and unremarkable imaging. Procedure-related factors include traumatic and persistent cannulation attempts, multiple injections of the pancreatic duct, pancreatic sphincterotomy, and, possibly, use of precut sphincterotomy. Aggressive hydration, use of rectal indomethacin, and prophylactic pancreatic stenting can diminish the risk (and likely severity) of PEP. Though hugely beneficial, these measures do not supersede careful patient selection and technique.

Prevention of postendoscopic retrograde cholangiopancreatography pancreatitis: the endoscopic technique

Pancreatitis is the most frequent and distressing complication of endoscopic retrograde cholangiopancreatography (ERCP). Many recent studies have reported the use of pharmacological agents to reduce post-ERCP pancreatitis (PEP); however, the most effective agents have not been established. Reduction in the incidence of PEP in high-risk patients has been reported through specific cannulation techniques such as guide wire-assisted cannulation and the use of pancreatic stents. The present review focuses on ERCP techniques for the prevention of PEP.

Complications of ERCP

Endoscopic retrograde cholangiopancreatography (ERCP) is performed commonly for therapy. Its role in pancreaticobiliary diagnostic imaging has significantly decreased over time. Despite advances in our knowledge of the risk factors, complications, (especially post-ERCP pancreatitis), remain a significant problem. This review highlights the risk factors as related to the patient, procedure and the endoscopist, and the possible means to prevent complications. The best way to avoid any complication is "to avoid any procedure where the indication is not strong" and especially to refrain from doing diagnostic ERCP when alternate noninvasive imaging such as magnetic resonance cholangiopancreatography is available.

Preventing pancreatitis after endoscopic retrograde cholangiopancreatography

Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis is a common and potentially devastating complication of ERCP. Advances in risk stratification, patient selection, procedure technique, and prophylactic interventions have substantially improved the endoscopists' ability to prevent this complication. This article presents the evidence-based approaches to preventing post-ERCP pancreatitis and suggests timely research questions in this important area.

Endoscopic approach to the patient with motility disorders of the bile duct and sphincter of Oddi

Since its original description by Oddi in 1887, the sphincter of Oddi has been the subject of much study. Furthermore, the clinical syndrome of sphincter of Oddi dysfunction (SOD) and its therapy are controversial areas. Nevertheless, SOD is commonly diagnosed and treated by physicians. This article reviews the epidemiology, clinical manifestations, and current diagnostic and therapeutic modalities of SOD.

Does rectal indomethacin eliminate the need for prophylactic pancreatic stent placement in patients undergoing high-risk ERCP? Post hoc efficacy and cost-benefit analyses using prospective clinical trial data

OBJECTIVES

A recent large-scale randomized controlled trial (RCT) demonstrated that rectal indomethacin administration is effective in addition to pancreatic stent placement (PSP) for preventing post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) in high-risk cases. We performed a post hoc analysis of this RCT to explore whether rectal indomethacin can replace PSP in the prevention of PEP and to estimate the potential cost savings of such an approach.

METHODS

We retrospectively classified RCT subjects into four prevention groups: (1) no prophylaxis, (2) PSP alone, (3) rectal indomethacin alone, and (4) the combination of PSP and indomethacin. Multivariable logistic regression was used to adjust for imbalances in the prevalence of risk factors for PEP between the groups. Based on these adjusted PEP rates, we conducted an economic analysis comparing the costs associated with PEP prevention strategies employing rectal indomethacin alone, PSP alone, or the combination of both.

RESULTS

After adjusting for risk using two different logistic regression models, rectal indomethacin alone appeared to be more effective for preventing PEP than no prophylaxis, PSP alone, and the combination of indomethacin and PSP. Economic analysis revealed that indomethacin alone was a cost-saving strategy in 96% of Monte Carlo trials. A prevention strategy employing rectal indomethacin alone could save approximately $150 million annually in the United States compared with a strategy of PSP alone, and $85 million compared with a strategy of indomethacin and PSP.

CONCLUSIONS

This hypothesis-generating study suggests that prophylactic rectal indomethacin could replace PSP in patients undergoing high-risk ERCP, potentially improving clinical outcomes and reducing healthcare costs. A RCT comparing rectal indomethacin alone vs. indomethacin plus PSP is needed.

How to interpret a functional or motility test - sphincter of oddi manometry

To date, endoscopic manometry is the best method for evaluating the function of the sphincter. Sphincter of Oddi manometry (SOM) remains the gold standard to correctly diagnose the sphincter of Oddi dysfunction (SOD) and stratify therapy. Several dynamic abnormalities relating to the intensity, frequency, and propagation of sphincter contractions have been described. However, their clinical use generally has been abandoned in favor of basal sphincter pressure alone, because this measurement is stable over time, and has stronger interobserver reliablility, reproducibility on repeating testing, and is associated with the responsiveness to therapy. A significant elevated risk of pancreatitis was attributed to the technique. The risk of pancreatitits associated with manometric evaluation of the pancreatic sphincter is markedly reduced when manometry is performed with continous aspiration from the pancreatic duct via one of the 3 catheter lumens. This section reviews indications, conscious sedative drugs, techniques, and the appropriate interpretations of SOM.

Endoscopic pancreatic duct stents reduce the incidence of post-endoscopic retrograde cholangiopancreatography pancreatitis in high-risk patients

BACKGROUND & AIMS

Pancreatitis is the most common and potentially serious complication of post-endoscopic retrograde cholangiopancreatography (ERCP). Post-ERCP pancreatitis (PEP) is caused mostly by postprocedural papillary edema and retention of pancreatic juice. We conducted a randomized controlled trial to determine whether placement of a temporary-type, pancreatic duct stent prevents PEP and to identify risk factors for PEP.

METHODS

We analyzed data from 426 consecutive patients who underwent ERCP-related procedures at 37 endoscopic units. The patients were assigned randomly to groups that received stents (S group, n = 213) or did not (nS group, n = 213). The stent used was temporary, 5F in diameter, 3 cm long, and straight with an unflanged inner end.

RESULTS

The overall frequency of PEP was 11.3%. The frequencies of PEP in the S and nS groups were 7.9% and 15.2%, respectively; the lower incidence of PEP in the S group was statistically significant based on the full analysis set (P = .021), although there was no statistically significant differences in an intention-to-treat analysis (P = .076). There were significant differences in PEP incidence between groups in multivariate analysis for the following risk factors: pancreatography first, nonplacement of a pancreatic duct stent after ERCP, procedure time of 30 minutes or more, sampling of pancreatic tissue by any method, intraductal ultrasonography, and difficulty of cannulation (≥15 min). Patients with more than 3 risk factors had a significantly greater incidence of pancreatitis.

CONCLUSIONS

Placement of a pancreatic duct stent reduces the incidence of PEP. Several risk factors are associated with PEP.

Prevention of Post-ERCP Pancreatitis

Pancreatitis is the most common complication of ERCP. It can be associated with substantial morbidity. Hence, the minimization of both the incidence and severity of post-ERCP pancreatitis is paramount. Considerable efforts have been made to identify factors that may be associated with an increased risk of this complication. In addition, both procedure- and pharmacological-related interventions have been proposed that may prevent this complication. This paper outlines these interventions and presents the evidence to support their use in the prevention of post-ERCP pancreatitis.

Recent developments in gastrointestinal motility

In the past decade, the results of many studies on gastrointestinal motility and perception have been published that may be relevant to the clinician. A new classification of oesophageal motor disorders has been proposed in which "ineffective oesophageal motility" largely replaces the former "non-specific oesophageal motor disorders". Recent studies have shown that the incidence of transient lower oesophageal sphincter relaxations can be reduced pharmacologically, and this may open doors to a new therapeutic approach in gastro-oesophageal reflux disease. The mechanisms through which hiatus hernia promotes reflux have become clearer. The recently developed technique of intraluminal impedance monitoring has made it possible to study oesophageal transit, non-acid reflux and its role in the generation of reflux symptoms, as well as the characteristics of belching. Measurement of gastric emptying by means of a non-radioactive isotope and breath-testing has become widely available but, unfortunately, this development has not yet been accompanied by the advent of new therapeutic options for gastroparesis. The term "enteric dysmotility" has been coined for the condition in which upper abdominal symptoms are associated with distinct small intestinal bowel motility disorders in the absence of ileus-like episodes. The role of high-amplitude propagated contractions in the pathogenesis of constipation has been further defined. In cases of suspected sphincter of Oddi dysfunction, manometry of both sphincters (IBD and pancreatic) is now felt to be advisable.

Minimizing complications in pancreaticobiliary endoscopy

Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound are invaluable tools in the diagnostic and therapeutic evaluation and management of a variety of pancreatobiliary disorders. Along with a significant refinement in the equipment and techniques used has come a recent trend toward aggressive therapeutic interventions. Because of the technical nature of these procedures and the characteristics of the patients, post-procedural complications may occur, ranging from minor (requiring brief hospitalization) to severe (causing permanent disability or death). This review summarizes these complications and outlines strategies to minimize them.

Sleeve sphincter of Oddi (SO) manometry: a new method for characterizing the motility of the sphincter of Oddi

BACKGROUND/PURPOSE

Perfused multilumen sphincter of Oddi (SO) manometry is accepted as the gold standard for diagnosis of SO dysfunction. However, this technique is associated with a relatively high incidence of post-procedure acute pancreatitis. In addition, triple-lumen manometry recordings may be difficult to interpret, as movement may produce artifacts. We have refined the development of a sleeve sensor for human SO manometry. This assembly aims to overcome the above limitations. In this study the accuracy of sleeve SO manometry (SOM) has been evaluated and compared with standard triple-lumen perfused SOM.

METHODS

Patients undergoing SO manometric studies consented to having both standard triple-lumen and sleeve SOM. A total of 32 paired studies were performed in 29 patients. Diagnosis was made only from standard triple-lumen SOM and the patient treated accordingly. For each study, SO basal pressure, contraction, amplitude, and frequency were recorded.

RESULTS

There was no statistically significant difference in the recordings of SO basal pressure, contraction, amplitude, and frequency between the two techniques. A strong correlation was demonstrated between SO basal pressure determined with the two catheters. The accuracy of sleeve SOM is comparable to standard triple-lumen SOM, with less movement artifact. One patient developed mild post-manometric pancreatitis.

CONCLUSIONS

The sleeve catheter records SO pressures with comparable values to standard triple-lumen SOM. The sleeve assembly potentially can replace the use of the perfused triple-lumen catheter for the objective diagnosis of SO dysfunction.

Acute pancreatitis: etiology, clinical presentation, diagnosis, and therapy

Acute pancreatitis is a relatively common disease that affects about 300,000 patients per annum in America with a mortality of about 7%. About 75% of pancreatitis is caused by gallstones or alcohol. Other important causes include hypertriglyceridemia, medication toxicity, trauma from endoscopic retrograde cholangiopancreatography, hypercalcemia, abdominal trauma, various infections, autoimmune, ischemia, and hereditary causes. In about 15% of cases the cause remains unknown after thorough investigation. This article discusses the causes, diagnosis, imaging findings, therapy, and complications of acute pancreatitis.

MRCP-secretin test-guided management of idiopathic recurrent pancreatitis: long-term outcomes

BACKGROUND

In patients with recurrent pancreatitis of unknown etiology and nondilated ducts, accurate morphofunctional evaluation of the pancreaticobiliary ductal system and sphincter of Oddi function is important in the diagnostic workup. However, ERCP and sphincter of Oddi manometry may be nondiagnostic and postprocedure complications may be frequent.

OBJECTIVE

Our purpose was to assess the diagnostic accuracy of the magnetic resonance cholangiopancreatography with secretin test (MRCP-S) in patients with recurrent acute pancreatitis of unknown etiology. Accuracy was established on the basis of ERCP findings and a minimum of 24 months' clinical follow-up.

DESIGN

Thirty-seven consecutive patients with intact gallbladder and a nondilated pancreaticobiliary ductal system with nonpathologic EUS findings entered a prospective MRCP-S-guided and ERCP-guided diagnostic and therapeutic study protocol.

RESULTS

Patients were followed up for a mean of 31.3 months (range 26-38 months). MRCP-S identified some pancreatic outflow impairment, suggesting morphofunctional dysfunction of either the major or minor papilla, in 12 of 37 patients (32.4%). The addition of ERCP to MRCP-S did not substantially improve the diagnostic yield for the etiology of recurrent pancreatitis, and 13.6% of cases had mild postprocedure pancreatitis. The S-test was abnormal in 12 of 20 cases (60%) in whom some dysfunction of the sphincter of Oddi or minor papilla was assumed on the basis of follow-up findings. The outcome was successful after biliary or pancreatic sphincterotomy in all patients with an abnormal S-test result. Sensitivity, specificity, and positive and negative predictive values of the S-test for the diagnosis of pancreatic outflow impairment at the major or minor papilla were, respectively, 57.1%, 100%, 100%, and 64%. When the test showed an abnormal result, we were unable to distinguish between biliary and pancreatic segment dysfunction of the sphincter of Oddi.

CONCLUSIONS

In idiopathic recurrent pancreatitis with nondilated ducts, the MRCP-S-guided approach gave diagnostic accuracy comparable to ERCP with regard to morphologic lesions, and it can be used as an alternative, avoiding ERCP-related complications in the diagnostic phase. An abnormal S-test result showed an excellent positive predictive value and somewhat disappointing negative predictive value for sphincter of Oddi or minor papilla dysfunction and for clinical success of therapeutic endoscopic approach.

Sphincter of Oddi dysfunction and pancreatitis

Sphincter of Oddi dysfunction (SOD) is a term used to describe a group of heterogenous pain syndromes caused by abnormalities in sphincter contractility. Biliary and pancreatic SOD are each sub-classified as type I, II or III, according to the Milwaukee classification. SOD appears to carry an increased risk of acute pancreatitis as well as rates of post ERCP pancreatitis of over 30%. Various mechanisms have been postulated but the exact role of SOD in the pathophysiology of acute pancreatitis is unknown. There is also an association between SOD and chronic pancreatitis but it is still unclear if this is a cause or effect relationship. Management of SOD is aimed at sphincter ablation, usually by endoscopic sphincterotomy (ES). Patients with type I SOD will benefit from ES in 55%-95% of cases. Sphincter of Oddi manometry is not necessary before ES in type I SOD. For patients with types II and III the benefit of ES is lower. These patients should be more thoroughly evaluated before performing ES. Some researchers have found that manometry and ablation of both the biliary and pancreatic sphincters is required to adequately assess and treat SOD. In pancreatic SOD up to 88% of patients will benefit from sphincterotomy. Therefore, there have been calls from some quarters for the current classification system to be scrapped in favour of an overall system encompassing both biliary and pancreatic types. Future work should be aimed at understanding the mechanisms underlying the relationship between SOD and pancreatitis and identifying patient factors that will help predict benefit from endoscopic therapy.

Sphincter of Oddi dysfunction and pancreatitis

Sphincter of Oddi dysfunction (SOD) is a term used to describe a group of heterogenous pain syndromes caused by abnormalities in sphincter contractility. Biliary and pancreatic SOD are each sub-classified as typeI, II or III, according to the Milwaukee classification. SOD appears to carry an increased risk of acute pancreatitis as well as rates of post ERCP pancreatitis of over 30%. Various mechanisms have been postulated but the exact role of SOD in the pathophysiology of acute pancreatitis is unknown. There is also an association between SOD and chronic pancreatitis but it is still unclear if this is a cause or effect relationship. Management of SOD is aimed at sphincter ablation, usually by endoscopic sphincterotomy (ES). Patients with typeISOD will benefit from ES in 55%-95% of cases. Sphincter of Oddi manometry is not necessary before ES in typeISOD. For patients with types II and III the benefit of ES is lower. These patients should be more thoroughly evaluated before performing ES. Some researchers have found that manometry and ablation of both the biliary and pancreatic sphincters is required to adequately assess and treat SOD. In pancreatic SOD up to 88% of patients will benefit from sphincterotomy. Therefore, there have been calls from some quarters for the current classification system to be scrapped in favour of an overall system encompassing both biliary and pancreatic types. Future work should be aimed at understanding the mechanisms underlying the relationship between SOD and pancreatitis and identifying patient factors that will help predict benefit from endoscopic therapy.

Review of idiopathic pancreatitis

Recent advances in understanding of pancreatitis and advances in technology have uncovered the veils of idiopathic pancreatitis to a point where a thorough history and judicious use of diagnostic techniques elucidate the cause in over 80% of cases. This review examines the multitude of etiologies of what were once labeled idiopathic pancreatitis and provides the current evidence on each. This review begins with a background review of the current epidemiology of idiopathic pancreatitis prior to discussion of various etiologies. Etiologies of medications, infections, toxins, autoimmune disorders, vascular causes, and anatomic and functional causes are explored in detail. We conclude with management of true idiopathic pancreatitis and a summary of the various etiologic agents. Throughout this review, areas of controversies are highlighted.

Prophylaxis of post-endoscopic retrograde cholangiopancreatography pancreatitis by an endoscopic pancreatic spontaneous dislodgement stent

BACKGROUND & AIMS

Pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP) is the most common and potentially serious complication of ERCP. The frequency of post-ERCP pancreatitis generally is reported to be between 1% and 9%. One cause of pancreatitis is retention of pancreatic juice resulting from papilledema after the procedure. We conducted a randomized controlled multicenter study to evaluate whether placement of a temporary pancreatic stent designed for spontaneous dislodgement prevents post-ERCP pancreatitis.

METHODS

The subjects were 201 consecutive patients who underwent ERCP. The patients were randomized into the stent placement group (S group = 98) or the nonstent placement group (nS group = 103). The stent used was 5F in diameter, 3 cm in length, straight, and unflanged inside.

RESULTS

Stents were placed successfully in 96% of the S group, and spontaneous stent dislodgment was recognized in 95.7% of those. The mean duration to dislodgment was 2 days, and there were no severe complications. The overall frequency of post-ERCP pancreatitis was 8.5%. The frequency of post-ERCP pancreatitis in the S and nS groups was 3.2% and 13.6%, respectively, showing a significantly lower frequency in the S group (P = .019). The mean increase in amylase level in the pancreatitis patients was significantly higher in the nS group (P = .014).

CONCLUSIONS

The randomized controlled multicenter trial showed that placement of a pancreatic spontaneous dislodgment stent significantly reduces post-ERCP pancreatitis.

Pancreatic sphincterotomy: Technique, indications, and complications

Pancreatic sphincterotomy serves as the cornerstone of endoscopic therapy of the pancreas. Historically, its indications have been less well-defined than those of endoscopic biliary sphincterotomy, yet it plays a definite and useful role in diseases such as chronic pancreatitis and pancreatic-type sphincter of Oddi dysfunction. In the appropriate setting, it may be used as a single therapeutic maneuver, or in conjunction with other endoscopic techniques such as pancreatic stone extraction or stent placement. The current standard of practice utilizes two different methods of performing pancreatic sphincterotomy: a pull-type sphincterotome technique without prior stent placement, and a needle-knife sphincterotome technique over an existing stent. The complications associated with pancreatic sphincterotomy are many, although acute pancreatitis appears to be the most common and the most serious of the early complications. As such, it continues to be reserved for those endoscopists who perform a relatively high-volume of therapeutic pancreaticobiliary endoscopic retrograde cholangio-pancreatography.

Early successes and late failures in the prevention of post endoscopic retrograde cholangiopancreatography

Acute pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). The only way to prevent this complication is to avoid an ERCP all together. Because of the risks involved, a careful consideration should be given to the indication for ERCP and the potential risk/benefit ratio of the test. Once a decision to perform an ERCP is made, the procedure should be carried out with meticulous care by an experienced endoscopist, and with a minimum of pancreatic duct opacification. Several pharmacologic agents have been tested, but to date the most important method of reducing post ERCP pancreatitis is the placement of pancreatic stent. Pancreatic stents should be placed in all patients at high risk of this complication such as those undergoing pancreatic sphincterotomy, pancreatic duct manipulation and intervention, and patients with suspected sphincter of Oddi dysfunction. Pancreatic stents should be also considered in patients requiring precut sphincterotomy to gain biliary access.

Incidence, risk factors, and prevention of post-ERCP pancreatitis

Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). Because of the potential risks and consequences of post-ERCP pancreatitis, considerable efforts have been made to define patient- and procedure-related factors that may be associated with an increased risk of this complication, along with determining interventions that can be done to reduce post-ERCP pancreatitis.

Pancreatits after endoscopic retrograde cholangio-pancreatography

Pancreatitis is the most common complication after endoscopic retrograde cholangio-pancreatography (ERCP); the reported incidence of this complication varies from less than 1% to 40%, but a rate of 4%-8% is reported in most prospective studies involving non-selected patients. Differences in criteria for defining pancreatitis, methods of data collection, and patient populations (i.e. number of high-risk patients included in the published series) are factors that are likely to affect the varying rates of post-ERCP pancreatitis. The severity of post-ERCP pancreatitis (PEP) can range from a minor inconvenience with one or two days of added hospitalization with full recovery to a devastating illness with pancreatic necrosis, multiorgan failure, permanent disability, and even death. Although, most episodes of PEP are mild (about 90%), a small percentage of patients (about 10%) develop moderate or severe pancreatitis. In the past, PEP was often viewed as an unpredictable and unavoidable complication, with no realistic strategy for its avoidance. New data have aided in stratification of patients into PEP risk categories and new measures have been introduced to decrease the risk of PEP. As most ERCPs are performed on an outpatient basis, the majority of patients will not develop PEP and can be discharged. Alternatively, early detection of those patients who will go on to develop PEP can guide decisions regarding hospital admission and aggressive management. In the last decade, great efforts have been addressed toward prevention of this complication. Points of emphasis have included technical measures, pharmacological prophylaxis, and patient selection. This review provides a comprehensive, evidence-based assessment of published data on PEP and current suggestions for its avoidance.

Solid state biliary manometry catheter: impact on diagnosis and post-study pancreatitis

Perfusion manometry of the sphincter of Oddi has been the standard for the investigation of patients with presumed sphincter of Oddi dysfunction (SOD). Microtransducer manometry (MTM) of the sphincter of Oddi represents an alternative to perfusion manometry. The technical success and reproducibility of MTM are as good as for perfusion manometry. Current data suggest that the upper limit for normal of basal sphincter of Oddi pressures measured with MTM lies at approximately 35 mm Hg. Pancreatitis risk after MTM in patients with SOD compares favorably with that after perfusion manometry. Low cost and ease of handling make MTM of the sphincter of Oddi an attractive alternative.

Frequency and severity of post-ERCP pancreatitis correlated with extent of pancreatic ductal opacification

BACKGROUND

Pancreatitis is the most common complication of diagnostic and therapeutic ERCP. Almost certainly, the etiology of this pancreatitis is multifactorial.

OBJECTIVE

The primary objective of this study was to evaluate the relationship between the extent of pancreatic ductal opacification and the frequency of pancreatitis.

DESIGN

Retrospective study.

SETTING

The ERCP database at our institution was searched for prospectively collected data from 1994 to 2005.

PATIENTS AND INTERVENTIONS

A total of 14,331 ERCPs were included in the analysis. Patients were divided into 4 groups according to the extent of pancreatic duct opacification: group 1, no attempted opacification or failed cannulation of the pancreatic duct (n = 6739); group 2, opacification of head only (n = 845); group 3, opacification of head and body (n = 2061); and group 4, opacification to the tail (n = 4685). The incidence and severity of pancreatitis was compared between and within each group.

RESULTS

The overall pancreatitis rate was 4.0%. There was a progressively higher frequency of pancreatitis with increased extent of opacification to the pancreatic ductal system (P < .001). The overall pancreatitis severity was mild in 2.9%, moderate in 0.8%, and severe in 0.3% of cases. There was a significant difference in pancreatitis severity between patients with pancreatogram (regardless of grade of filling) and patients without pancreatogram. (P < .001). However, there was no difference in the pancreatitis severity between groups 2 to 4 (patients with pancreatogram). Age (65 years vs >65 years), sex, and type of procedure performed (diagnostic and therapeutic) were not significantly different beyond the extent of pancreatic ductal opacification. Multivariate analysis showed that suspected sphincter of Oddi dysfunction with manometry and the extent of pancreatic duct opacification were independent predictors of post-ERCP pancreatitis.

CONCLUSIONS

Less filling of the pancreatic ductal system was associated with less post-ERCP pancreatitis. Before performing endoscopic retrograde pancreatography, endoscopists should carefully evaluate whether any pancreatogram or what extent of pancreatogram is needed clinically. Greater use of noninvasive pancreatography and less use of endoscopic retrograde pancreatography should decrease post-ERCP pancreatitis.

Predictors of outcomes after biliary and pancreatic sphincterotomy for sphincter of oddi dysfunction

BACKGROUND

There are few data on combined pancreatic and biliary sphincterotomy for sphincter of Oddi dysfunction (SOD), especially regarding clinical features that might predict outcomes. We sought to examine the relative importance of various clinical features and the presence or absence of objective biliary abnormalities in determining responses to endoscopic therapy.

METHODS

A cohort of consecutive patients with suspected SOD was treated with biliary sphincterotomy, with additional pancreatic sphincterotomy at initial or subsequent endoscopic retrograde cholangiopancreatography if there was abnormal pancreatic manometry in conjunction with pain refractory to biliary sphincterotomy, continuous pain, or a history of amylase elevation. Repeat intervention was offered until response was achieved or complete ablation of all treated sphincters was achieved. Response was assessed by patients using a 5-point Likert scale, and multivariate logistic regression analysis used to identify predictors of response.

RESULTS

Of 121 patients, 112 (92%) were female, 105 (87%) postcholecystectomy, and by modified Milwaukee biliary classification 18 (15%) were type I, 53 (44%) type II, and 50 (41%) type III. All patients underwent biliary sphincterotomy and 49 (40%) pancreatic sphincterotomy. Good or excellent response at final follow-up was reported by 83 (69%) of 121 patients, including 37 (61%) of 61 patients requiring repeated intervention. Response was not significantly different between biliary types I, II, and III. Patient characteristics (with adjusted odds ratios) that were significant predictors of poor response were normal pancreatic manometry (4.6), delayed gastric emptying (6.0), daily opioid use (4.0), and age <40 (2.7). Abnormal liver function tests or dilated bile duct were not significant.

CONCLUSIONS

For the treatment of SOD incorporating pancreatic and biliary sphincterotomy, patient characteristics and pancreatic sphincter manometry may be more important predictors of outcome than the traditional classification based on liver chemistries and bile duct dilation.

Systematic review: sphincter of Oddi dysfunction--non-invasive diagnostic methods and long-term outcome after endoscopic sphincterotomy

BACKGROUND

Sphincter of Oddi dysfunction is a benign, functional gastrointestinal disorder for which invasive endoscopic therapy with potential complications is often recommended.

AIMS

To review the available evidence regarding the diagnostic accuracy of non-invasive methods that have been used to establish the diagnosis and to estimate the long-term outcome after endoscopic sphincterotomy.

METHODS

A systematic review of English language articles and abstracts containing relevant terms was performed.

RESULTS

Non-invasive diagnostic methods are limited by their low sensitivity and specificity, especially in patients with Type III sphincter of Oddi dysfunction. Secretin-stimulated magnetic resonance cholangiopancreatography appears to be useful in excluding other potential causes of symptoms, and morphine-provocated hepatobiliary scintigraphy also warrants further study. Approximately 85%, 69% and 37%, of patients with biliary Types I, II and III sphincter of Oddi dysfunction, respectively, experience sustained benefit after endoscopic sphincterotomy. In pancreatic sphincter of Oddi dysfunction, approximately 75% of patients report symptomatic improvement after pancreatic sphincterotomy, but the studies have been non-controlled and heterogeneous.

CONCLUSIONS

Patients with suspected sphincter of Oddi dysfunction, particularly those with biliary Type III, should be carefully evaluated before considering sphincter of Oddi manometry and endoscopic sphincterotomy. Further controlled trials are needed to justify the invasive management of patients with biliary Type III and pancreatic sphincter of Oddi dysfunction.

Is sphincter of Oddi manometry a risk factor for pancreatitis? A different view

Studies suggest a causal relationship between sphincter of Oddi manometry (SOM) and acute pancreatitis, presumably due to water instillation in the ductal system. In this article, critical analysis of the existing studies attributes the high risk of acute pancreatitis with SOM to "association due to confounding" rather than to "causation." This conclusion is based on two pieces of evidence: The first is lack of biologic plausibility: Biologic evidence is lacking to support the hypothesis that water instillation during SOM can induce acute pancreatitis. The second is confounding evidence: Manometric studies show considerable variation in the risk of post-procedure pancreatitis (4% to 30%), which suggests that other important factors besides SOM influence the adverse outcome. These studies did not control for other variables, which are well known to predispose to pancreatitis and therefore may act as confounding factors. Two studies that assessed the independent role of SOM in causation of acute pancreatitis showed that SOM is not an independent predictor of acute pancreatitis. It is the underlying disorder sphincter of Oddi dysfunction, and not the "SOM" procedure, that predisposes patients to post-procedure acute pancreatitis.

Technical outcomes and complications of ERCP in children

BACKGROUND

The aim of this study was to compare the success and complications of diagnostic and therapeutic ERCP in children (age <18 years) and adult patients.

METHODS

A retrospective case-controlled study was conducted in which all children undergoing ERCP at two centers (1994-2002) were identified from endoscopy databases and were matched with adult patients for all variables (e.g., indication, procedure complexity) except age. Outcomes with regard to technical success and complications were compared between the adult and the pediatric cohorts. Grade of procedure complexity and procedure-related complications were defined by using established criteria.

RESULTS

A total of 116 children (mean age 9.3 years, range 1 month to 17 years; median age 8.1 years) and 116 matched adult patients (mean age 56.3 years, range 20-83 years; median age 49.7 years) underwent 163 and 173 ERCP procedures, respectively. According to procedure complexity grade, each group included the same number of patients, grade I, 72 patients; grade II, 12 patients; and grade III, 32 patients. Procedure success rate was 97.5% in children vs. 98% in the adult cohort (p= not significant). The complication rate was not significantly different between children and adult patients (3.4% vs. 2.5%). Most complications were of mild severity and encountered only in patients who underwent grade III procedures, with the exception of a single adult in whom moderate post-sphincterotomy bleeding developed after extraction of a large bile duct stone (grade II complexity).

CONCLUSIONS

When ERCP is performed in children by expert endoscopists, the success rate is high and the complication rate is low, both being comparable with those for ERCP in adult patients.

Normal sphincter of oddi motor function

With the introduction of endoscopic retrograde cholangiopancreatography (ERCP) manometry, the characteristics of sphincter of Oddi (SO) motor activity have been described. SO manometry is the only available method to measure SO motor activity directly and is usually performed at the time of ERCP. SO manometry is considered to be the gold standard for evaluating patients for sphincter dysfunction. This review reports the technique of SO manometry and normal values for SO manometry. SO motility is characterized by prominent phasic contractions superimposed on a tonic pressure. Elevated basal SO pressure is the most consistent and reliable criteria to diagnose SO dysfunction. Basal pressures obtained from the biliary sphincter are similar to the basal pressure obtained from the pancreatic sphincter. Abnormal SO manometric values are shown. Factors that influence SO pressures, and interpretation of SO manometric tracing are discussed. The most common and serious complication of SO manometry is post-manometry pancreatitis. In healthy volunteers with normal sphincter function, pancreatitis is almost never seen. However, in patients with SO dysfunction, the incidence of pancreatitis is high. The use of new nonperfused microtransducers may reduce this complication.

Sphincter of Oddi manometry does not predispose to post-ERCP acute pancreatitis

BACKGROUND

Sphincter of Oddi manometry is helpful in selecting patients with sphincter of Oddi dysfunction who will respond to sphincterotomy. However, studies have shown that sphincter of Oddi manometry is associated with a high risk of post-procedure pancreatitis. The primary objective of this study was to evaluate the safety of sphincter of Oddi manometry in patients with sphincter of 2Oddi dysfunction. The secondary objective was to determine the risk factors for post-ERCP pancreatitis in patients with sphincter of Oddi dysfunction.

METHODS

Data were collected retrospectively for 268 patients who had elective ERCP performed at 3 tertiary care medical centers between 1996 and 2000. Consecutive patients with suspected sphincter of Oddi dysfunction formed the case group; the control group consisted of patients with bile duct stone. The case group was further subclassified into group A, patients who underwent sphincter of Oddi manometry followed by immediate ERCP, and group B, patients who had ERCP without manometry. The rate of post-ERCP acute pancreatitis was compared between case and control groups.

RESULTS

Twenty-seven percent of patients in the case group with suspected sphincter of Oddi dysfunction developed acute pancreatitis compared with 3.2% of patients in the control group with bile duct stone (p<0.001). There was no significant difference in the rate of acute pancreatitis in patients with sphincter of Oddi dysfunction who underwent sphincter of Oddi manometry and ERCP compared with patients with sphincter of Oddi dysfunction who had ERCP without sphincter of Oddi manometry (odds ratio 0.72: 95% CI[0.08, 9.2]). Multivariable logistic regression analysis showed that biliary sphincterotomy (p=0.006) and pancreatography (p=0.03) were independent predictors of acute pancreatitis.

CONCLUSIONS

Patients with suspected sphincter of Oddi dysfunction are at higher risk of post-ERCP acute pancreatitis. Sphincter of Oddi manometry by itself does not appear to predispose to this complication.

Secretin MRCP and endoscopic pancreatic manometry in the evaluation of sphincter of Oddi function: a comparative pilot study in patients with idiopathic recurrent pancreatitis

BACKGROUND

Sphincter of Oddi dysfunction plays an important etiologic role in idiopathic acute recurrent pancreatitis. Sphincter of Oddi manometry is the most accurate test of sphincter of Oddi function, but it is associated with an increased risk of post-procedure pancreatitis and is non-diagnostic in about a third of cases. Secretin MRCP has a diagnostic efficacy comparable to ERCP, but data on its sensitivity with regard to sphincter of Oddi function are lacking. The aim of this study was to compare secretin MRCP and pancreatic sphincter of Oddi manometry for evaluation of sphincter of Oddi function in patients with idiopathic acute recurrent pancreatitis.

METHODS

Eighteen consecutive patients with idiopathic acute recurrent pancreatitis underwent secretin MRCP and pancreatic sphincter of Oddi manometry/ERCP. Data from 15 patients were suitable for analysis. Fifteen subjects with asymptomatic, non-pancreatic hyperamylasemia matched for age and gender underwent secretin MRCP and served as a control group.

RESULTS

Sphincter of Oddi manometry documented sphincter dysfunction in 6/15 patients (40%) and secretin MRCP, in 4/15 patients (26.7%). Sphincter of Oddi manometry confirmed the presence of elevated basal sphincter of Oddi pressure in two of the 4 patients with abnormal and other forms of sphincter of Oddi dyskinesia in the other two. None of the control subjects had an abnormal secretin MRCP. Secretin MRCP and sphincter of Oddi manometry were concordant in 13/15 patients (86.7%); positive and negative diagnoses for sphincter of Oddi dysfunction agreed in, respectively, 81.8% and 100% (kappa value 0.706).

CONCLUSIONS

Secretin MRCP seems to be a useful noninvasive procedure for investigation of pancreatic sphincter of Oddi function, but evaluation in larger series is needed.

Adverse outcomes of endoscopic retrograde cholangiopancreatography: avoidance and management

Adverse outcomes of endoscopic retrograde cholangiopancreatography (ERCP) include technical failures and complications. Complications cause significant morbidity to patients and anxiety to endoscopists. The key to preventing complications is to understand which patients and procedures are at highest risk so that appropriate decisions can be made as to whether ERCP should be performed at all, and if so, how. Patients who need ERCP the least are often the ones most likely to develop complications. For marginal indications, ERCP should be avoided. Success rates are higher and complication rates lower for endocopists performing large numbers by endoscopists with adequate experience.

Key issues in sphincter of Oddi dysfunction

SOD is a challenging condition that is difficult to diagnose and treat. The high failure rate of endoscopic and surgical treatment reflects the difficulties in establishing accurate diagnosis and the lack of specific objective criteria by which appropriate therapy could be determined. In general, sphincter ablation should be offered for type I patients. An initial trial of medical therapy is appropriate for type II patients with mild-to-moderate symptoms and for all type III patients. SOM is highly recommended for type II patients and is mandatory for all type III patients if sphincter ablation is contemplated. Other causes of abdominal pain such as chronic pancreatitis or functional disorders should be considered in patients not benefiting from sphincter ablation. All procedures on the sphincter should be undertaken with caution after meticulous investigation, and patient selection should be based on strict objective criteria.

Effects of droperidol on the pancreatic and biliary sphincters

BACKGROUND

Performance of sphincter of Oddi manometry at ERCP is technically demanding and requires that the patient be well sedated. Droperidol is frequently administered when adequate sedation cannot be achieved with a benzodiazepine and meperidine. This study examined the effects of droperidol on the biliary and pancreatic sphincters.

METHODS

A total of 31 patients were prospectively evaluated by sphincter of Oddi manometry in the conventional retrograde fashion. Manometry was initially performed with intravenous administration of diazepam alone, diazepam plus meperidine or midazolam plus meperidine. Manometry was then repeated 5 minutes after droperidol was administered.

RESULTS

The basal pressure of the biliary sphincter and of the pancreatic sphincter were not significantly altered by droperidol. Concordance (normal vs. abnormal) between the basal sphincter pressure before and after droperidol was seen in 30 patients (97%). Droperidol also did not lead to a difference in phasic wave amplitude, duration, or frequency. Thirteen manometry tracings (42%) were judged as being qualitatively better after droperidol, whereas two (6.5%; </= p 0.001) were qualitatively better before droperidol administration.

CONCLUSIONS

Droperidol does not significantly affect sphincter of Oddi manometric parameters. It appears that it can be added to the armamentarium of agents needed for performance of sphincter of Oddi manometry. However, further study is needed to determine whether recent safety concerns with droperidol use are valid.

Idiopathic acute pancreatitis

After routine investigations, including a thorough history, routine laboratory study, and noninvasive imaging with transcutaneous ultrasonogram, 10% to 25% of cases of acute pancreatitis have no readily identifiable cause and are termed idiopathic. But modern medicine has made notable advances in uncovering various causes of acute pancreatitis, and several new diagnostic tools that allow clinicians to less invasively approach the patient without sacrificing the diagnostic yield have been introduced. By being knowledgeable of these new changes and by their proper use in a proper circumstances, clinicians will be able to find the cause more accurately and earlier. This better management will not only improve the well-being of the patients but also reduce the number of "true" idiopathic acute pancreatitis to a minimum.

Controversies in clinical pancreatology: should the sphincter of Oddi be measured in patients with idiopathic recurrent acute pancreatitis, and should sphincterotomy be performed if the pressure is high?

The risk benefit ratio of measuring the sphincter of Oddi pressure and performing sphincterotomy in patients with idiopathic acute pancreatitis with high sphincter pressures has not been assessed. Few healthy controls have had sphincter measurements so that the definition of an abnormal sphincter remains understudied. The procedures involved have significant risks and the benefits are hard to measure considering the variable natural history of this disorder. No prospective, randomized investigations have been performed to evaluate efficacy of these invasive procedures. It is the author's opinion that until appropriate studies prove efficacy that these interventions be considered experimental.

Sphincter of Oddi dysfunction

Biliary-like pain alone, or associated with a transient increase in liver or pancreatic enzyme, may be the clinical manifestations of sphincter of Oddi dysfunction. Since it is not always possible to dissociate functional conditions from subtle structural changes, the term sphincter of Oddi dysfunction is used to define motility abnormalities caused by 'sphincter of Oddi stenosis' and 'sphincter of Oddi dyskinesia'. Both sphincter of Oddi stenosis and sphincter of Oddi dyskinesia may account for obstruction to flow through the sphincter of Oddi and may thus induce retention of bile in the biliary tree and pancreatic juice in the pancreatic duct. Most of the clinical information concerning sphincter of Oddi dysfunction refers to post-cholecystectomy patients who have been arbitrarily classified according to clinical presentation, laboratory results and endoscopic retrograde cholangiopancreatography findings in: (a) biliary type I, (b) biliary type II, and (c) biliary type III. Prevalence of biliary-type of pain has been reported to vary from 1 to 1.5% in unselected postcholecystectomy people, to 14% in a selected group of patients complaining of postcholecystectomy symptoms. The frequency of sphincter of Oddi dysfunction, as shown by manometry, differs in the different clinical subgroups: 65-95% in biliary group I, mainly due to sphincter of Oddi stenosis; 50-63% in biliary type II, and 12-28% in biliary type III. In patients with idiopathic recurrent pancreatitis, sphincter of Oddi dysfunction varies from 39 to 90%. Diagnostic work-up of postcholecystectomy patients for suspected sphincter of Oddi dysfunction includes liver biochemistry and pancreatic enzymes, plus negative findings of structural abnormalities. Usually, this would include transabdominal ultrasound and endoscopic retrograde cholangiopancreatography. Depending on the available resources, endoscopic ultrasound and magnetic resonance cholangiography may precede endoscopic retrograde cholangiopancreatography in specific clinical conditions. Quantitative evaluation of bile transit from the hepatic hilum to the duodenum at choledochoscintigraphy appears valuable in the decision to undertake sphincter of Oddi manometry or to treat. Sphincterotomy is the standard treatment for sphincter of Oddi dysfunction. In biliary type I patients, the indication for endoscopic sphincterotomy is straightforward without the need of any additional investigation. Slow bile transit in biliary type II is an indication to undergo endoscopic sphincterotomy without sphincter of Oddi manometry. Slow bile transit in biliary type III patients is an indication to perform sphincter of Oddi manometry. Diagnostic work-up of patients with gallbladder in situ is part of the same diagnostic algorithm that has initially excluded the presence of a gallbladder dysfunction.