Walled-off Pancreatic Necrosis Research Articles

Lumen-Apposing Metal Stents for Walled-Off Pancreatic Necrosis: A Practice Pattern Survey of Gastroenterologists

<h2>ABSTRACT</h2><h3>Background & Aims</h3> Endoscopic ultrasound-guided placement of LAMS has emerged as an effective treatment for WON following acute necrotizing pancreatitis, but a standardized management protocol has not yet emerged. We sought to characterize practice variations in the use of lumen-apposing metal stents (LAMS) for the treatment of walled-off pancreatic necrosis (WON). <h3>Methods</h3> A 30-question survey was sent to 341 endoscopists in the United States to collect information on practitioner demographics, procedural practices, necrosectomy practices, and LAMS-related adverse events. <h3>Results</h3> A total of 69 of the 341 surveys were completed for a response rate of 20.2%. Almost all reported using LAMS placement as the primary method of WON treatment (92.5%). At the time of LAMS placement, almost half of respondents perform balloon dilation (45.2%), and a minority place pigtail stents through the LAMS channel (15.0%). Necrosectomy is performed by less than half during index LAMS placement procedure (46.8%). Approximately half never use hydrogen peroxide lavage (52.4%). Most respondents reported experiencing adverse events at some point. About half reported a stent indwell time of the greater than 1 month. <h3>Conclusion</h3> A convergence of practice patterns when using LAMS to treat WON has not been demonstrated. Considerable variability exists in certain aspects of LAMS use including placement technique, necrosectomy practices, follow-up treatment, and stent removal. Further investigation is necessary to standardize this procedure to effectively and safely treat WON.

Is pancreatic-enteric drainage a definitive operation for pancreatitis associated pancreatic fluid collections?

Presenter: Patrick McLaren MD | Methodist Richardson Medical Center Background: Pancreatic pseudocysts and walled off pancreatic necrosis (WOPN) are complications of severe pancreatitis. Pancreatic-enteric drainage procedures have become standard therapy for symptomatic collections. However, conversion to a pancreatic resection, usually a distal pancreatosplenectomy, is needed in the event of treatment failure of drainage alone. The need for pancreatic resection following cyst-enteric drainage procedure is not well studied. We aimed to quantify the rate of conversion from surgical cystogastrostomy to pancreatic resection and identify predictors of failure. Methods: A single institution retrospective review was conducted to identify all patients undergoing cystogastrostomy between 2012-2020 using CPT procedure codes. Demographic, disease, and treatment characteristics were identified. Failure of surgical drainage was defined as need for subsequent pancreatic resection. Characteristics between failure and non-failure groups were compared using non-parametric statistical tests to identify predictors of treatment failure. Results: A total of 24 cystogastrostomies were performed over the 8-year study period for pancreatic pseudocyst or WOPN. The most common cause of pancreatitis was biliary (n=15, 63%). Cyst diameter ranged from 7.6 - 26.2 cm (mean 14.8 cm). Overall complication rate of cyst-enteric drainage procedure was 25% (3/24). There were no mortalities. All patients initially reported resolution of their symptoms, however, three patients (12.5%) required a subsequent distal pancreatectomy after surgical drainage. Mean time to resection from index operation was 14.7 months. Indication for resection was persistent recurrent abdominal pain in all resection patients. There was no difference between drainage alone and failure of drainage groups with respect to comorbidities: HTN (p=0.277), Diabetes (p=0.371), Tobacco use (p=0.249), and Weight loss at presentation (p=0.69). Mean cyst size at initial drainage was no different between drainage alone and failure groups (15.2cm vs 10.3cm, p=0.51). Estimated blood loss at initial operation was similar between groups (126 mL vs 166 mL, p=0.36). Conclusion: In our series, pancreatic drainage procedure was successful initial management of pancreatic fluid collections, with 12.5% requiring subsequent resection. Our data suggests that upfront drainage without resection offers a largely successful operation that allows for pancreatic tissue preservation with low mortality and morbidity. We did not identify any predictors of failure of initial drainage. Resection with distal pancreatectomy for WOPN and pseudocysts can be reserved for cases of failure of management with drainage alone.

Endoscopic drainage of walled-off pancreatic necrosis: is necrosectomy and delayed drainage necessary?

Introduction: While studies have suggested that endoscopic step up approach with delayed drainage (more than 28 days from symptom onset) produce the best outcome in the treatment of walled-off pancreatic necrosis (WOPN), we assessed our single centre experience with endoscopic drainage of WOPN, in particular, the necessity of necrosectomy and delayed drainage. Methods: Patients who underwent endoscopic drainage for WOPN between October 2011 and June 2019 in Monash Health were identified. They were excluded if follow up data were missing. The included patients' medical records, pathology results, imaging findings and procedure reports were retrospectively reviewed. The outcomes were then compared between early drainage (within 28 days of symptom onset) and delayed drainage cohorts. Results: 38 patients were included for analysis. The population underwent an average of 2.45 endoscopic drainages per patient with none requiring endoscopic necrosectomy. 31.58%% of patients required percutaneous drainage for distant collections and 2 patients received surgical necrosectomy. A disease related mortality of 15.8% and an average length of stay (LOS) of 75.71 days were reported. No statistically significant difference was shown in disease -related mortality (27.3% vs. 11.1%, p = 0.215) or LOS (90.9 vs 69.5, p=0.2905) between early and delayed drainage cohorts, but patients who received early drainage were more unwell at day 18 of symptom onset (qDOFA score 1 vs. 0.3, p= 0.033). Conclusion: Endoscopic drainage in combination with selective percutaneous drainage is effective in the management of walled-off pancreatic necrosis. Early drainage should be considered for patient who remained unstable despite conservative management.

Step-up mini invasive surgical treatment of patients with different morphological forms of acute necrotizing pancreatitis

Introduction: Despite significant progress in the treatment strategy of acute necrotizing pancreatitis (ANP), mortality in cases of its severe form remains high. There is no single point of view concerning the indications for the use of mini invasive interventions depending on the nature, extension and localization of the pathological foci of ANP. Material: We performed a prospective observational cohort study of efficacy of elaborated algorithmic mini invasive step-up approach of surgical treatment of 317 patients with different morphological forms of ANP. The following parameters were collected for each episode: length of hospital stay, mortality, occurrence of organ failure and local complications. Results: Transcutaneous punction/drainages were applied as the first step in 37 patients with acute necrotic collections (ANC). In the presence of walled-off pancreatic necrosis (WOPN) EUS procedures were preferred in case their close localization to the stomach or duodenum in 65 observations. Initial surgical treatment wasn't effective in 18.8% and video-assisted retroperitoneal debridement (VARD) in patients with ANC or necrosectomies under EUS control in cases of WOPN were applied. Necessary for laparotomic necrosectomies occurred in 14.5% of patients and was the final step of proposed algorithmic approach. During postoperative period complications occurred in 28.3% of patients. They included 7 new episodes of organ failure, 4 cases of arosive hemorrhage, and 5 observations of pancreatic and duodenal fistulas. Overall mortality rate was 3.3%, after interventional treatment - 6.5%. Conclusion: Surgical treatment in patients with ANP based on elaborated algorithmic step-up approach is followed by acceptable complication and mortality level.

Laparoscopic transgastric necrosectomy for walled-off pancreatic necrosis

Laparoscopic transgastric necrosectomy for walled-off pancreatic necrosis

International, multicenter retrospective trial comparing the efficacy and safety of bi-flanged versus lumen-apposing metal stents for endoscopic drainage of walled-off pancreatic necrosis.

BackgroundTo compare fully covered bi-flanged metal stents (BFMS) and lumen-apposing metal stents (LAMS) for endoscopic ultrasound (EUS)-guided drainage/debridement of pancreatic walled-off necrosis (WON).MethodsPatients with WON managed by EUS-guided therapy were divided into those who underwent: 1) drainage using BFMS; and 2) drainage using LAMS and scheduled direct endoscopic necrosectomy (DEN). Clinical success (resolution of the WON), technical success (successful stent placement), and adverse events (AEs) were evaluated.Results387 patients underwent WON endoscopic drainage, 205 using BFMS and 182 using LAMS. The clinical success in the BFMS or LAMS groups were similar (197 [96.1%] vs. 174 [95.6%]; P=0.81). Median number of procedures required for WON resolution was significantly lower in BFMS compared to LAMS (2 vs. 3, P<0.001). Technical success for stent placement was similar in BFMS and LAMS groups (203 [99%] vs. 180 [99%], P=0.90). Procedure-related AEs were similar in the BFMS and LAMS groups (19 [9.3%] vs. 20 [10.9%], P=0.61). Stent dysfunction with occluding debris was higher in the BFMS group compared to LAMS group (21 [10.2 %] vs. 11 [5.9%], P=0.04). The migration rate was higher in the BFMS group than in the LAMS group (15 [7.3%] vs. 3 [1.6%]; P<0.001). DEN was required in 23 [11.2%] patients in the BFMS group after lack of WON resolution by conservative means.ConclusionBFMS with a “step-up approach” and LAMS with scheduled DEN are both safe and effective for EUS-guided drainage/debridement of WON.

Robotic-assisted Roux-en-Y cystojejunostomy and debridement of walled-off pancreatic necrosis

Robotic-assisted Roux-en-Y cystojejunostomy and debridement of walled-off pancreatic necrosis

When Should We Perform Endoscopic Drainage and Necrosectomy for Walled-Off Necrosis?

Endoscopic drainage and necrosectomy are now accepted treatment approaches for patients with symptomatic walled-off pancreatic necrosis (WON). The current recommendations advocate step-up approaches for the treatment of symptomatic WON. Previous recommendations stipulated that endoscopic intervention should be delayed until more than four weeks after the onset. Recent data on early drainage have been increasing and this option might be considered in well-encapsulated cases, but the percutaneous route is preferred if the drainage is performed within two weeks after onset or in nonencapsulated cases. Recently, additional drainage methods, such as the multiple gateway technique and multiple stent placement, have been developed to open up multiple dead spaces in the WON cavity. Endoscopic necrosectomy could be performed via the transluminal route or percutaneous route after failed initial and additional drainage procedures. The use of novel lumen-apposing stents is a promising treatment option that could reduce the number of steps, the procedure time, and the overall number of necrosectomies.

What is the Impact of the Proportion of Solid Necrotic Content on the Number of Necrosectomies during EUS-Guided Drainage using Lumen-Apposing Metallic Stents of Pancreatic Walled-off Necrosis ?

The fully-covered, lumen apposing metal stents are designed for one step placement, facilitating the direct endoscopic necrosectomy into the walled-off pancreatic necrosis. However, the prediction of the number of necrosectomy sessions in these patients is not known. This study evaluated the association between the proportion of solid necrotic material inside walled-off necrosis, as assessed during the endosonography placement of a lumen apposing metal stent, and the number of necrosectomies subsequently required. Patients from three tertiary medical centers with symptomatic walled off pancreatic necrosis (pain, infection, gastric/biliary obstruction) at more than 4 weeks after onset of acute pancreatitis were retrospectively analysed. Proportion of solid necrotic debris was estimated during endosonography procedure of lumen apposing metal stents placement. Necrosectomy was performed when obstruction or inflammation occurred subsequently. Lumen apposing metal stents were removed after clearance of necrotic content. In 46 patients with successful lumen apposing metal stents placement, necrosectomy was performed in 39 patients (72.78%). Performance of 3 or more necrosectomies was significantly associated with more than 50% pancreatic necrosis (p=0.032), but not with walled-off pancreatic necrosis size or location. Necrotic infection during lumen apposing metal stents stenting was associated with hypoalbuminemia, but not with necrosectomy requirement. Clinical success after a median follow-up of 13.37 months was 87%. Walled-off pancreatic necrosis with more than 50% solid necrotic content were associated with more necrosectomy procedures, requiering longer endoscopy time, intravenous sedations, and higher costs.

A Comparison of Endoscopic Versus Surgical Creation of a Cystogastrostomy to Drain Pancreatic Pseudocysts and Walled-Off Pancreatic Necrosis in 5500 Patients.

To determine the success, morbidity, and mortality rates of endoscopic and surgical creation of pancreatic cystenterostomies for the drainage of peripancreatic fluid collections, pseudocysts with necrotic debris, and walled-off pancreatic necrosis. Endoscopic methods of cystenterostomy creation to drain pancreatic pseudocysts (with and without necrotic debris) and infected peripancreatic fluid collections are perceived to be less morbid than surgery. Contemporary reports document a very high complication rate with endoscopic methods. A meta-analysis of 5500 patients. Open and laparoscopic surgical techniques to drain chronic pancreatic pseudocysts, infected pancreatic fluid collections, and walled-off pancreatic necrosis are more successful with less morbidity and mortality than endoscopic methods. In regards to a surgical step-up approach to treat chronic infected pancreatic fluid collections or walled-off pancreatic necrosis, surgical creation of a cystenterostomy is more successful with fewer complications than endoscopic methods and should be given priority if less invasive or conservative methods fail.

Endoscopic gastric fenestration of debriding pancreatic walled-off necrosis: A pilot study.

BACKGROUNDEndoscopic drainage of walled-off necrosis (WON) is still a challenge due to stent-associated problems. We explored endoscopic gastric fenestration (EGF) as an innovative alternative intervention.AIMTo assess the feasibility, efficacy and safety of EGF for WON.METHODSBetween March 2019 and March 2020, five patients with symptomatic WON in close contact with the stomach wall were treated by EGF. Endoscopic ultrasound (EUS) was used to select appropriate sites for gastric fenestration, which then proceeded layer by layer as in endoscopic submucosal dissection. Both the stomach muscularis propria and pseudocyst capsule were penetrated. Fenestrations were expanded up to 1.5-3 cm for drainage or subsequent necrosectomy.RESULTSEGF failed in Case 1 due to nonadherence of WON to the gastric wall. EGF was successfully implemented in the other four cases by further refinement of fenestration site selection according to computed tomography, endoscopy and EUS features. The average procedure time for EGF was 124 min (EUS assessment, 32.3 min; initial fenestration, 28.8 min; expanded fenestration, 33 min), and tended to decrease as experience gradually increased. The diameter of the fenestration site was 1.5-3 cm, beyond the caliber of a lumen-apposing metal stent (LAMS), to ensure effective drainage or subsequent necrosectomy. Fenestration sites showed surprising capacity for postoperative self-healing within 1-3 wk. No EGF-related complications were seen. WON disappeared within 3 wk after EGF. In Case 3, another separate WON, treated by endoscopic LAMS drainage, recurred within 4 d after LAMS removal due to stent-related hemorrhage, and resolved slowly over almost 3 mo. No recurrences were observed in the five patients.CONCLUSIONEGF is an innovative and promising alternative intervention for WON adherent to the gastric wall. The challenge resides in the gauging of actual adherence and in selecting appropriate fenestration sites.

Asymptomatic walled-off pancreatic necrosis after hospital discharge: natural course and risk factors for complications

Asymptomatic walled-off pancreatic necrosis after hospital discharge: natural course and risk factors for complications

Safety and efficacy of lumen-apposing metal stents versus plastic stents to treat walled-off pancreatic necrosis: systematic review and meta-analysis.

Background and study aims Lumen-apposing metal stents (LAMS) are increasingly used for drainage of walled-off pancreatic necrosis (WON). Recent studies suggested greater adverse event (AE) rates with LAMS for WON. We conducted a systematic review and meta-analysis to compare the safety and efficacy of LAMS with double-pigtail plastic stents (DPPS) for endoscopic drainage of WON. The primary aim was to evaluate stent-related AEs. Methods In October 2019, we searched the Ovid (Embase, MEDLINE, Cochrane) and Scopus databases for studies assessing a specific LAMS or DPPS for WON drainage conducted under EUS guidance. Safety outcomes were AE rates of bleeding, stent migration, perforation, and stent occlusion. Efficacy outcomes were WON resolution and number of procedures needed to achieve resolution. A subanalysis including non-EUS-guided cases was performed. Results Thirty studies including one randomized controlled trial (total 1,524 patients) were analyzed. LAMS were associated with similar bleeding (2.5 % vs. 4.6 %, P = 0.39) and perforation risk (0.5 % vs. 1.1 %, P = 0.35) compared to DPPS. WON resolution (87.4 % vs. 87.5 %, P = 0.99), number of procedures to achieve resolution (2.09 vs. 1.88, P = 0.72), stent migration (5.9 % vs. 6.8 %, P = 0.79), and stent occlusion (3.8 % vs. 5.2 %, P = 0.78) were similar for both groups. Inclusion of non-EUS-guided cases led to significantly higher DPPS bleeding and perforation rates. Conclusions LAMS and DPPS were associated with similar rates of AEs and WON resolution when limiting analysis to EUS-guided cases. Higher bleeding rates were seen in historical studies of DPPS without EUS guidance. Additional high-quality studies of WON treatment using consistent outcome definitions are needed.

Removing lumen-apposing metal stent stopped bleeding from splenic artery pseudoaneurysm during transmural drainage of walled-off pancreatic necrosis.

Removing lumen-apposing metal stent stopped bleeding from splenic artery pseudoaneurysm during transmural drainage of walled-off pancreatic necrosis.

S3321 Recurrent Acute Pancreatitis Secondary to Pancreatic Divisum Anomaly

INTRODUCTION: Pancreatic divisum (PD) is a congenital malformation that occurs when the ventral and dorsal ducts of the pancreas fail to fuse. Inadequate drainage of pancreatic secretions from the minor papilla results in ductal distension and recurrent pancreatitis. We present a patient with PD who developed acute necrotizing pancreatitis (ANP) complicated by walled off pancreatic necrosis (WOPN). CASE DESCRIPTION/METHODS: 64-year-old female with history of chronic alcohol abuse and IBD presented with epigastric abdominal pain and emesis. Labs showed normal triglycerides, elevated lipase and amylase. Abdominal US ruled out gallstones. Abdominal CT showed pancreatic inflammation with several cystic-appearing fluid collections. She was treated conservatively. Repeat abdominal CT showed multiple increased peripancreatic fluid collections with mass effect on the stomach (Figure 1). Persistent abdominal pain led to ERCP which displayed complete PD and high-grade pancreatic duct fistula in the body and tail. Ventral and dorsal duct sphincterotomies were done with stent deployment in each duct. EUS revealed 3 peripancreatic fluid collections (consistent with WOPN); the largest was adjacent to the gastric antrum. Purulent drainage was noted after 3 cystogastrostomy incisions. Antibiotics were initiated. Patient eventually had recurrent pancreatitis, requiring repeat minor papilla sphincterotomy with dorsal pancreatic duct stent exchange. DISCUSSION: WOPN is a late complication of ANP, occurring more than 4 weeks after the initial attack. It can cause obstruction and fistula. Due to her PD anatomy, we suspect the patient had previous indolent acute pancreatitis episodes however they were falsely attributed to her IBD. Thus, delaying diagnosis of acute pancreatitis and leading to ANP and WOPN. The lifetime risk of pancreatitis in PD patients is similar to the general population. Consider PD in young, female patients in whom etiologies such as, gallstones and alcohol use, have been excluded. Alcohol abuse in context of her PD anatomy could have amplified our patient’s risk of acute pancreatitis. CT and MRI scans do not reliably detect PD thus ERCP remains the diagnostic test. Minor papilla sphincterotomy, papillary dilatation, stent insertion and pancreatic resection are treatment options. Since recurrent acute pancreatitis can lead to chronic pancreatitis, it is important to detect PD early. Follow up imaging in 3-6 months after pancreatitis resolution is vital, especially in patients with WOPN, to exclude neoplasm.Figure 1Figure 2.: Fig 1. and 2: CT abdomen and pelvis with contrast showing significantly compressed gastric lumen and multiloculated collections surrounding the pancreas, along the fundus of the stomach measuring 8 × 4.3 cm with mass effect, slightly inferiorly along the fundus and body measuring 7.7 × 4.2 cm, and along the antrum measuring 7.9 × 4.3 cm with surrounding fat stranding and mass effect.

S0960 Evaluation of the Efficacy and Safety of Lumen Apposing Metal Stents for Peripancreatic Fluid Collection Drainage Without Double Pigtail Stent Placement: Our Experience in a Large Community Hospital

INTRODUCTION: Acute pancreatitis (AP) is sometimes accompanied by fluid collections and necrosis. These include acute pancreatic fluid collections (PFCs), pancreatic pseudocysts, acute necrotic collections (ANCs), and walled off pancreatic necrosis (WOPN). Indications for drainage of the PFCs include infection, bleeding, luminal obstruction, fistulization, and biliary obstruction. Currently endoscopic drainage is considered standard of care. Cautery enhanced lumen-apposing metal stents (LAMS) is a tool to facilitate potentially safer and easier endoscopic drainage of pancreatic fluid collections. Some endoscopists prefer placing double pigtail stents (DPS) within the LAMS, while others do not. Rationale for DPS within LAMS is to reduce potential adverse events like bleeding, stent occlusion & infections. We perform endoscopic drainage without placing DPS within the LAMS. We propose that placing DPS within LAMS does not decrease adverse events associated with LAMS placement. METHODS: We conducted a retrospective study of patients with cautery enhanced LAMS placed for pseudocyst or WOPN between January 1, 2017 and November 30, 2019. We evaluated the efficacy and safety of LAMS. Adverse events were categorized into two: early- occurring within 48 hours and late occurring after 48 hours. RESULTS: This study had 18 patients with the following characteristics: 10 males and 8 females; 8 Caucasians, 9 African Americans and 1 Hispanic; and the average age was 48 yrs. The clinical findings showed a similar etiology of pancreatitis for gallstones and alcohol. All LAMS deployed were 15mm in diameter. The average size of collection drained was 114.11 mm with an average duration of stent placement of approx. 52 days. Overall, 8 patients required necrosectomy. Of those that required a necrosectomy, 2 patients required 1 session, and 6 required multiple sessions. In all patients, only one early adverse event was found: Stent mal-deployment. None of the patients required re-intervention as there was complete/near complete resolution of PFC at 3 months follow-up. CONCLUSION: Successful resolution of pancreatic fluid collections may be achieved endoscopically. Our data suggest that deployment of LAMS reduces the rate of adverse events and reinterventions. The additional deployment of double pigtail stents through LAMS, as suggested by the Shamah et al. 2018 paper may not be needed. Further prospective, randomized study in a larger sample size is warranted to validate these results.Table 1

S3083 Predictors of Surgical Intervention in Patients Who Underwent Endoscopic Therapy for Symptomatic Walled-Off Pancreatic Necrosis Using Lumen-Apposing Metal Stents: A Single Center Case Series

S3083 Predictors of Surgical Intervention in Patients Who Underwent Endoscopic Therapy for Symptomatic Walled-Off Pancreatic Necrosis Using Lumen-Apposing Metal Stents: A Single Center Case Series

S1861 EUS Gastric Access for Therapeutic Endoscopy for Management of Walled-Off Pancreatic Necrosis With a Lumen Apposing Metal Stent in Gastric Bypass Anatomy

S1861 EUS Gastric Access for Therapeutic Endoscopy for Management of Walled-Off Pancreatic Necrosis With a Lumen Apposing Metal Stent in Gastric Bypass Anatomy

S1445 A Tough WON: A Complicated Case of Walled-Off Pancreatic Necrosis

S1445 A Tough WON: A Complicated Case of Walled-Off Pancreatic Necrosis

Multiple extra-splanchnic venous thromboses - an unusual vascular complication of acute pancreatitis.

Acute pancreatitis (AP) is an acute inflammatory process of the pancreas with variable clinical presentations. Splanchnic venous thrombosis is a well-known vascular complication of AP and commonly present as thrombosis of the splanchnic venous system: splenic vein (SplV), portal vein (PV) and superior mesenteric vein (SMV), either separately or in combinations. Involvement of extra-splanchnic vessels is rare and associated with morbidity and mortality. Vascular complications are late phenomena and usually associated with local complications of AP, namely acute fluid collections, necrotizing pancreatitis and walled-off pancreatic necrosis. Pathogenesis of venous thrombosis is multifactorial in which pancreatic inflammation and systemic inflammatory response play a key role. At present, there are no consensus guidelines on treatment and use of anticoagulation for venous thrombosis in the setting of AP. Limited literature suggests the use of anticoagulation in presence of PV with or without SMV thrombosis and extrasplanchnic vessel involvement. Literature on extra-splanchnic vessels involvement in acute pancreatitis is sparse. Here we present two cases with multiple extra-splanchnic vessels involvement and their management.