Endoscopic "step-up approach" using a dedicated biflanged metal stent reduces the need for direct necrosectomy in walled-off necrosis (with videos)

Role of imaging in evaluating the complications of endoscopic management of pancreatic fluid collections in acute pancreatitis

Acute pancreatitis is associated with local and systemic complications. Pancreatic fluid collection (PFC) is the most common local complication. Infected or symptomatic PFCs need drainage. Endoscopic drainage (ED) is the first-line procedure for accessible PFCs adjacent to the stomach and duodenum. ED is performed under endoscopic ultrasound (EUS) guidance. The technical and clinical success rates of EUS-guided ED in well-encapsulated PFCs are high. ED of poorly encapsulated PFCs is associated with complications. Bleeding and perforation are the most common complications. Contrast-enhanced computed tomography is critical in planning ED and early detection and management of complications. With the increasing utilization of ED for PFC, the radiologist must be familiar with the ED techniques, types of stents, and the complications related to ED. In this review, we discuss the technical aspects of the ED as well as the imaging findings of ED-related complications.

Postponed endoscopic necrosectomy results in a lower rate of additional intervention for infected walled-off necrosis

Although endoscopic necrosectomy (EN) is more frequently used to manage walled-off necrosis (WON), there is still debate over how much time should pass between the initial stent placement and the first necrosectomy. This study aims to determine the effect of performing EN within different timings after placing the initial stent on clinical outcomes for WON. A retrospective study on infected WON patients compared an early necrosectomy within one week after the initial stent placement with a necrosectomy that was postponed after a week. The primary outcomes compared the rate of clinical success and the need for additional intervention after EN to achieve WON resolution. 77 patients were divided into early and postponed necrosectomy groups. The complete resolution of WON within six months of follow-up was attained in 73.7% and 74.3% of patients in both the early and postponed groups. The early group tended to a greater need for additional intervention after EN (26.8% early necrosectomy vs. 8.3% postponed necrosectomy, P = 0.036). Our study does not demonstrate that early necrosectomy is superior to postponed necrosectomy in terms of clinical success rate, total count of necrosectomy procedures, procedure-related complications, length of hospitalization and prognosis. Conversely, patients in the postponed group received fewer additional interventions.

Efficacy and Safety of Anhydrous Ethanol-Assisted Endoscopic Ultrasound-Guided Transluminal Necrosectomy in Infected Necrotizing Pancreatitis

AIM

Endoscopic necrosectomy has become the first-line treatment option for infectious necrotizing pancreatitis (INP), especially walled-off necrosis. However, the problems, including operation-related adverse events (AEs) and the need for multiple endoscopic procedures, have not been effectively addressed. We sought to evaluate the clinical safety and efficacy of anhydrous ethanol-assisted endoscopic ultrasound (EUS)-guided transluminal necrosectomy in INP.

METHODS

A single-center observational cohort study of INP patients was conducted in a tertiary endoscopic center. Anhydrous ethanol-assisted EUS-guided transluminal necrosectomy (modified group) and conventional endoscopic necrosectomy (conventional group) were retrospectively compared in INP patients. The technical and clinical success rates, operation time, perioperative AEs, postoperative hospital stay, and recurrent INP rates were analyzed, respectively.

RESULTS

A total of 55 patients were enrolled. No statistically significant differences were observed between the two groups regarding baseline characteristics. Compared to patients in the conventional group, patients in the modified group demonstrated significantly reduced times of endoscopic transluminal necrosectomies (1.96 ± 0.89 vs. 2.73 ± 0.98; P = 0.004) and comparable perioperative AEs (P = 0.35). Meanwhile, no statistically significant differences were observed in the technical and clinical success rates (P = 0.92), operation time (P = 0.59), postoperative hospital stay (P = 0.36), and recurrent INP rates (P = 1.00) between the two groups.

CONCLUSION

Anhydrous ethanol-assisted EUS-guided transluminal necrosectomy seemed safe and effective in treating INP. Compared with conventional endoscopic transluminal necrosectomy, its advantage was mainly in reducing the number of endoscopic necrosectomies without increasing perioperative AEs.

Risk factors for adverse outcomes at various phases of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Data from a multi-institutional consortium

OBJECTIVES

No comprehensive study has examined short- and long-term adverse outcomes of endoscopic ultrasound (EUS)-guided treatment of pancreatic fluid collections (PFCs) including walled-off necrosis (WON) and pseudocysts.

METHODS

In a multi-institutional cohort of 357 patients receiving EUS-guided treatment of PFCs (228 with WON and 129 with pseudocysts), we examined PFC type-specific risk factors for procedure-related adverse events (AEs), clinical failure, and recurrence. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the logistic and Cox regression models, respectively, adjusting for potential confounders.

RESULTS

Adverse events were observed predominantly in WON, and risk factors were WON extension to the pelvis (OR 2.49; 95% CI 1.00-6.19) and endoscopic necrosectomy (OR 5.15; 95% CI 1.61-16.5). Risk factors for clinical failure in WON treatment included higher Charlson Comorbidity Index (OR for ≥3 vs. ≤2, 2.58; 95% CI 1.05-6.35), extension to the pelvis (OR 3.63; 95% CI 1.57-8.43), nonuse of a lumen-apposing metal stent (OR 2.88; 95% CI 1.10-7.54), and percutaneous drainage (OR 3.73; 95% CI 1.27-10.9). Patients with pseudocysts extending to the paracolic gutter and the need for more than two endoscopic/percutaneous procedures had ORs for clinical failure of 5.28 (95% CI 1.10-25.3) and 5.52 (95% CI 1.61-18.9), respectively. Pseudocysts requiring the multigateway approach were associated with a high risk of recurrence (HR 4.00; 95% CI 1.11-11.6).

CONCLUSION

The adverse outcomes at various phases of EUS-guided PFC treatment may be predictable based on clinical parameters. Further research is warranted to optimize treatment strategies for high-risk patients.

Endoscopic ultrasound-guided drainage of pancreatic collections with dedicated metal stents: A nationwide, multicenter, propensity score-matched comparison

BACKGROUND

The new dedicated stents for endoscopic ultrasound (EUS)-guided transluminal drainage of peri‑pancreatic fluid collections (PFCs) demonstrated optimal efficacy and safety profiles.

AIMS

This study aimed to evaluate the safety, technical and clinical success, and recurrence rate of PFCs drained with Lumen Apposing Metal Stent (LAMS) or Bi-Flanged Metal Stent (BFMS).

METHODS

Data from a multicenter series of PFCs treated with LAMS or BFMS at 30 Italian centers during a 5-year period were retrieved. The rate of adverse events (AEs), technical success, clinical success, PFC recurrence were evaluated. To overcome biases, a 1-to-1 match was created using propensity score analysis.

RESULTS

Out of 476 patients, 386 were treated with LAMS and 90 with BFMS, with a median follow-up of 290 days (95% CI 244 to 361). Using propensity score matching, 84 patients were assigned to each group. The incidence of AEs did not differ between the two stents (13.1% versus 15.5%, p = 0.29), mainly bleeding or recurrence rate (4.7% versus 3.5%, p = 1). Technical and clinical success in the BFMS and LAMS groups were 92% versus 95% (p = 0.36) and 91% versus 94% (p = 0.64), respectively.

CONCLUSION

Our study demonstrates that LAMS and BFMS have comparable safety profiles with similar technical and clinical success rates for EUS-guided PFC drainage.

A novel lumen-apposing metal stent for endoscopic drainage of symptomatic pancreatic fluid collections: a retrospective study

Background and Objectives

Previous studies showed that lumen-apposing metal stent (LAMS) provides a feasible route to perform direct endoscopic necrosectomy. However, the high risk of bleeding and migration induced by the placement of LAMS attracted attention. The aim of this study was to evaluate the safety and effectiveness of a novel LAMS.

Methods

In this retrospective study, we enrolled patients with symptomatic pancreatic fluid collections (PFCs) to perform EUS-guided drainage with a LAMS in our hospital. Evaluation variables included technical success rate, clinical success rate, and adverse events.

Results

Thirty-two patients with a mean age of 41.38 ± 10.72 years (53.1% males) were included in our study, and the mean size of PFC was 10.06 ± 3.03 cm. Technical success rate and clinical success rate reached 96.9% and 93.8%, respectively. Stent migration occurred in 1 patient (3.1%), and no stent-induced bleeding occurred. The outcomes of using LAMS in 10 patients with pancreatic pseudocyst and 22 patients with walled-off necrosis were comparable. Compared with pancreatic pseudocyst, walled-off necrosis needed more direct endoscopic necrosectomy times to achieve resolution (P = 0.024).

Conclusions

Our study showed that the novel LAMS is effective and safe for endoscopic drainage of PFCs with a relatively low rate of adverse events. Further large-scale multicenter studies are needed to confirm the present findings.

Endoscopic ultrasound-guided drainage of early pancreatic necrotic collection: Single-center retrospective study

BACKGROUND

Endoscopic ultrasound (EUS)-guided drainage is the standard of care for drainage of pancreatic necrosis. Though initially it was mainly used for drainage of only walled-off necrosis, recently, a few studies have also shown its safety in the management of acute necrotic collections. We did a retrospective study to evaluate the safety and efficacy of EUS-guided drainage in the early phase of pancreatitis as compared to interventions in the late phase.

METHODS

We retrieved baseline disease-related, procedure-related and outcome-related details of patients who underwent EUS-guided drainage of pancreatic necrosis. Patients were divided into early (≤ 28 days from onset of pancreatitis) or delayed (> 28 days) drainage groups. Both groups were compared for disease-related characteristics and outcomes.

RESULTS

Total 101 patients were included in the study. The mean age of included patients was 35.54 ± 13.58 years and 75 were male. Thirty-five patients (34.7%) underwent early drainage. In the early group, a majority of patients underwent intervention due to infected collection (88.6% vs. 18.2%; p < 0.001). More patients in the early group had < 30% wall formation (28.6% vs. 0%; p < 0.001) and > 30% solid debris within the collection (42.9% vs. 15.2%; p = 0.005). Patients in the early group were also more likely to require endoscopic necrosectomy (57.1% vs. 27.3%; p = 0.003) and additional percutaneous drainage (31.4% vs. 12.1%; p = 0.018). Overall, three patients in the early group and one patient in the delayed group had procedure-related complications. Four patients in the early group and one patient in the delayed group succumbed to illness (p = 0.029).

CONCLUSION

Though delayed interventions remain standard of care in the management of acute pancreatitis, some patients may require early intervention due to infected collection with deteriorating clinical status. Early EUS-guided interventions in such carefully selected patients have in similar clinical outcomes and complication rates compared to delayed intervention. However, such patients are more likely to require additional endoscopic or percutaneous interventions.

Management of Disconnected Pancreatic Duct

Disconnected pancreatic duct (DPD) is common after acute necrotizing pancreatitis (ANP). Its clinical implications vary according to the course of disease. In the early phase of ANP, parenchymal necrosis along with disruption of pancreatic duct cause acute necrotic collection that evolves into walled-off necrosis (WON). In the later phase, DPD becomes evident as confirmed by magnetic resonance cholangiopancreatography. Clinical manifestations of DPD can vary from being asymptomatic, recurrent pain, recurrent pancreatic fluid collection (PFC), obstructive pancreatitis, or external pancreatic fistula (EPF). Few patients develop new-onset diabetes. Long-term indwelling plastic stents have been proposed to prevent the recurrent PFC.

Endoscopic treatment of pancreatic necrosis: Still searching for perfection!

Over last few years, there has been a paradigm shift in the management of infected pancreatic necrosis with endoscopic and minimally invasive "step-up" management approach replacing open surgical necrosectomy. Because of being associated with reduced occurrence of new onset multi-organ failure, external pancreatic fistulae, shorter hospital stay, lower costs, and better quality of life compared with minimally invasive surgical approach, endoscopic "step-up" management approach is the preferred intervention for endoscopically accessible pancreatic necrotic collections at expert centers with endoscopic expertise. Development of lumen apposing metal stents and improvised accessories for interventional endoscopic ultrasound has revolutionized the endoscopic management of pancreatic necrosis making it more effective and safer. Despite these promising developments, endoscopic transluminal necrosectomy (ETN) remains the Achilles heel. Lack of dedicated endoscopic accessories, poor endoscopic visualization within the necrotic cavity, limited diameter of the instrument channel of the endoscope that is a significant impediment to remove large amount of necrotic material, and uncertain ability to avoid vessels and vital structures in the necrotic cavity are important limitations during endoscopic necrosectomy. Recent devices and solutions including use of cap assisted necrosectomy, over the scope grasper and powered endoscopic debridement device are welcome steps in our pursuit for an ideal, safer, and efficacious ETN device. This review will discuss recent advances as well as challenges in the endoscopic management of pancreatic necrosis.

WONDER-01: immediate necrosectomy vs. drainage-oriented step-up approach after endoscopic ultrasound-guided drainage of walled-off necrosis-study protocol for a multicentre randomised controlled trial

BACKGROUND

With the increasing popularity of endoscopic ultrasound (EUS)-guided transmural interventions, walled-off necrosis (WON) of the pancreas is increasingly managed via non-surgical endoscopic interventions. However, there has been an ongoing debate over the appropriate treatment strategy following the initial EUS-guided drainage. Direct endoscopic necrosectomy (DEN) removes intracavity necrotic tissue, potentially facilitating early resolution of the WON, but may associate with a high rate of adverse events. Given the increasing safety of DEN, we hypothesised that immediate DEN following EUS-guided drainage of WON might shorten the time to WON resolution compared to the drainage-oriented step-up approach.

METHODS

The WONDER-01 trial is a multicentre, open-label, superiority, randomised controlled trial, which will enrol WON patients aged ≥ 18 years requiring EUS-guided treatment in 23 centres in Japan. This trial plans to enrol 70 patients who will be randomised at a 1:1 ratio to receive either the immediate DEN or drainage-oriented step-up approach (35 patients per arm). In the immediate DEN group, DEN will be initiated during (or within 72 h of) the EUS-guided drainage session. In the step-up approach group, drainage-based step-up treatment with on-demand DEN will be considered after 72-96 h observation. The primary endpoint is time to clinical success, which is defined as a decrease in a WON size to ≤ 3 cm and an improvement of inflammatory markers (i.e. body temperature, white blood cell count, and C-reactive protein). Secondary endpoints include technical success, adverse events including mortality, and recurrence of the WON.

DISCUSSION

The WONDER-01 trial will investigate the efficacy and safety of immediate DEN compared to the step-up approach for WON patients receiving EUS-guided treatment. The findings will help us to establish new treatment standards for patients with symptomatic WON.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05451901, registered on 11 July 2022. UMIN000048310, registered on 7 July 2022. jRCT1032220055, registered on 1 May 2022.

Combined Drainage and Protocolized Necrosectomy Through a Coaxial Lumen-apposing Metal Stent for Pancreatic Walled-off Necrosis: A Prospective Multicenter Trial

OBJECTIVE

We evaluated a protocolized endoscopic necrosectomy approach with a lumen-apposing metal stent (LAMS) in patients with large symptomatic walled-off pancreatic necrosis (WON) comprising significant necrotic content, with or without infection.

SUMMARY BACKGROUND DATA

Randomized trials have shown similar efficacy of endoscopic treatment compared with surgery for infected WON.

DESIGN

We conducted a regulatory, prospective, multicenter single-arm clinical trial examining the efficacy and safety of endoscopic ultrasound -guided LAMS with protocolized necrosectomy to treat symptomatic WON ≥6 cm in diameter with >30% solid necrosis. After LAMS placement, protocolized WON assessment was conducted and endoscopic necrosectomy was performed for insufficient WON size reduction and persistent symptoms. Patients with radiographic WON resolution to ≤ 3 cm and/or 60-day LAMS indwell had LAMS removal, then 6-month follow-up. Primary endpoints were probability of radiographic resolution by 60 days and procedure-related serious adverse events.

RESULTS

Forty consecutive patients were enrolled September 2018 to March 2020, of whom 27 (67.5%) were inpatients and 19 (47.5%) had clinical evidence of infection at their index procedure. Mean WON size was 15.0 ± 5.6 cm with mean 53.2% ± 16.7% solid necrosis. Radiographic WON resolution was seen in 97.5% (95% CI, 86.8%, 99.9%) by 60 days, without recurrence in 34 patients with 6-month follow-up data. Mean time to radiographic WON resolution was 34.1 ± 16.8 days. Serious adverse events occurred in 3 patients (7.5%), including sepsis, vancomycin-resistant enterococcal bacteremia and shock, and upper gastrointestinal bleeding. There were no procedure-related deaths.

CONCLUSIONS

Endoscopic ultrasound-guided drainage with protocolized endoscopic necrosectomy to treat large symptomatic or infected walled-off necrotic pancreatic collections was highly effective and safe. Clinicaltrials.-gov no: NCT03525808.

Controversies in the management of acute pancreatitis: An update

This review summarized the current controversies in the management of acute pancreatitis (AP). The controversies in management range from issues involving fluid resuscitation, nutrition, the role of antibiotics and antifungals, which analgesic to use, role of anticoagulation and intervention for complications in AP. The interventions vary from percutaneous drainage, endoscopy or surgery. Active research and emerging data are helping to formulate better guidelines. The available evidence favors crystalloids, although the choice and type of fluid resuscitation is an area of dynamic research. The nutrition aspect does not have controversy as of now as early enteral feeding is preferred most often than not. The empirical use of antibiotics and antifungals are gray zones, and more data is needed for conclusive guidelines. The choice of analgesic is being studied, and the recommendations are still evolving. The position of using anticoagulation is still awaiting consensus. The role of intervention is well established, although the modality is constantly changing and favoring endoscopy or percutaneous drainage rather than surgery. It is evident that more multicenter randomized controlled trials are required for establishing the standard of care in these crucial management issues of AP to improve the morbidity and mortality worldwide.

Novel classification system for walled-off necrosis: a step toward standardized nomenclature and risk-stratification framework

BACKGROUND AND AIMS

The optimal therapeutic approach for walled-off necrosis (WON) is not fully understood, given the lack of a validated classification system. We propose a novel and robust classification system based on radiologic and clinical factors to standardize the nomenclature, provide a framework to guide comparative effectiveness trials, and inform the optimal WON interventional approach.

METHODS

This was a retrospective analysis of patients who underwent endoscopic management of WON by lumen-apposing metal stent placement at a tertiary referral center. Patients were classified according to the proposed QNI classification system: quadrant ("Q"), represented an abdominal quadrant distribution; necrosis ("N"), denoted by the percentage of necrosis of WON; and infection ("I"), denoted as positive blood culture and/or systemic inflammatory response syndrome reaction with a positive WON culture. Two blinded reviewers classified all patients according to the QNI system. Patients were then divided into 2 groups: those with a lower QNI stratification (≤2 quadrants and ≤30% necrosis; group 1) and those with a higher stratification (≥3 quadrants, 2 quadrants with ≥30% necrosis, or 1 quadrant with >60% necrosis and infection; group 2). The primary outcome was mean time to WON resolution. Secondary procedural and clinical outcomes between the groups were compared.

RESULTS

Seventy-one patients (75% men) were included and stratified by the QNI classification; group 1 comprised 17 patients and group 2, 54 patients. Patients in group 2 had a higher number of necrosectomies, longer hospital stays, and more readmissions. The mean time to resolution was longer in group 2 than in group 1 (79.6 ± 7.76 days vs 48.4 ± 9.22 days, P = .02). The mortality rate was higher in group 2 (15% vs 0%, P = .18).

CONCLUSIONS

Despite the heterogeneous nature of WON in severe acute pancreatitis, a proposed QNI system may provide a standardized framework for WON classification to inform clinical trials, risk-stratify the disease course, and potentially inform an optimal management approach.

Controversies in EUS-guided treatment of walled-off necrosis

This review gives an overview of different techniques in the treatment of post-acute complications of acute pancreatitis. The endoscopic treatment of those complications is currently standard of care. EUS opened up the broad implementation of internal drainage methods to make them safe and effective. Due to different endoscopic approaches worldwide, controversies have arisen that are pointed out in this paper. The main focus was placed on weighing up evidence to find the optimal approach. However, if no evidence can be provided, the authors, experienced in the field, give their personal advice.

Endoscopic step up: When and how

The management of (peri)pancreatic collections has undergone a paradigm shift from open surgical drainage to minimally invasive endoscopic, percutaneous, or surgical interventions. Minimally invasive interventions are associated with less morbidity and mortality compared to open necrosectomy. The (peri)pancreatic collections are currently treated with a “step-up approach” of an initial drainage procedure followed, if necessary, by a more invasive debridement. The step-up approach for management of (peri)pancreatic collections is mainly of two types, namely, surgical and endoscopic. Surgical step up includes initial image-guided percutaneous catheter drainage followed, if necessary, by minimally invasive video-assisted retroperitoneal debridement. Endoscopic step-up approach includes endoscopic transluminal drainage followed, if necessary by direct endoscopic necrosectomy. The development of endoscopic ultrasound and lumen apposing metal stents (LAMSs) has revolutionized the endoscopic management of (peri)pancreatic collections. Compared to surgical step-up approach, endoscopic step-up treatment approach has been reported to be associated with less new-onset organ failure, pancreatic fistula, enterocutaneous fistula, or perforation of visceral organ and shorter hospital/intensive care unit stay. This review will mainly focus on indications, techniques, timing, and recent advances related to endoscopic step-up approach in management of symptomatic(peri)pancreatic collections.

Impact of transmural plastic stent on recurrence of pancreatic fluid collection after metal stent removal in disconnected pancreatic duct: a randomized controlled trial

BACKGROUND

Disconnected pancreatic duct (DPD) after development of walled-off necrosis (WON) predisposes to recurrent (peri)pancreatic fluid collection (PFC). In this randomized controlled trial, we compared plastic stents with no plastic stent after removal of a large-caliber metal stent (LCMS) on incidence of recurrent PFCs in DPD. METHODS : Consecutive patients with WON who underwent endoscopic ultrasound (EUS)-guided drainage with LCMS between September 2017 and March 2020 were screened for eligibility. At LCMS removal (4 weeks after drainage), patients with DPD were randomized to plastic stent or no stent groups. The primary outcome was incidence of recurrent PFC at 3 months. Secondary outcomes were technical success of plastic stent deployment, adverse events, stent migration, and recurrence of PFC at 6 and 12 months.

RESULTS

236 patients with WON underwent EUS-guided drainage using LCMS, and 104 (males 94, median age 34 years (interquartile range [IQR] 26-44.7) with DPD were randomized into stenting (n = 52) and no-stenting (n = 52) groups. Plastic stent deployment was successful in 88.5 %. Migration occurred in 19.2 % at median follow-up of 8 months (IQR 2.5-12). Recurrent PFCs occurred in six patients at 3 months (stent n = 3, no stent n = 3). There was no significant difference in PFC recurrence between the two groups at 3, 6, and 12 months. Reintervention was required in seven patients with recurrent PFCs, with no significant difference between the two groups.

CONCLUSION

In patients with WON and DPD, deployment of plastic stents after LCMS removal did not reduce recurrence of PFC.

Hydrogen peroxide-assisted endoscopic necrosectomy of pancreatic walled-off necrosis: a systematic review and meta-analysis

BACKGROUND AND AIMS

Use of hydrogen peroxide (H₂O₂) has been reported in direct endoscopic necrosectomy (DEN) of pancreatic walled-off necrosis (WON). The aim of this meta-analysis was to study the pooled clinical outcomes of H₂O₂-assisted DEN of pancreatic WON.

METHODS

We conducted a comprehensive search of several databases (inception to July 2021) to identify studies reporting on the use of H₂O₂ in DEN of WON. A random-effects model was used to calculate pooled rates and I² values, and 95% prediction intervals were used to assess heterogeneity. The outcomes studied were technical success, clinical success, and adverse events in H₂O₂-assisted DEN of pancreatic WON.

RESULTS

In 7 analyzed studies, 186 patients underwent H₂O₂-assisted DEN of WON. The pooled rate of technical success was 95.8% (95% confidence interval [CI], 88.5-98.5), clinical success was 91.6% (95% CI, 86.1-95), and cumulative rate of overall adverse events was 19.3% (95% CI, 7.6-41). The pooled rate of bleeding was 7.9% (95% CI, 2.4-22.7), stent migration was 11.3% (95% CI, 4.9-23.9), perforation 5.4% (95% CI, 1.7-15.7), infection 5.7% (95% CI, 2-15.1), and pulmonary adverse event 2.9% (95% CI, 1.3-6.1). Mean treatment sessions ranged from 2 to 5.

CONCLUSIONS

H₂O₂-assisted DEN of WON demonstrated excellent clinical outcomes, with minimal heterogeneity. No adverse events attributable to H₂O₂ were reported. Future controlled studies are warranted comparing the clinical outcomes with and without H₂O₂ before H₂O₂ use can be established in DEN of pancreatic WON.

Endoscopic Ultrasound-guided Drainage of Patients With Infected Walled-off Necrosis: Which Stent to Choose?

BACKGROUND

Endoscopic ultrasound (EUS)-guided drainage is the preferred treatment of pancreatic fluid collections (PFC). However, the choice of the stent for EUS-guided drainage in critically ill PFC cases with infected walled-off necrosis (WON) and/or organ failure (OF) remains unknown.

MATERIALS AND METHODS

Between January 2018 and December 2019, consecutive patients with symptomatic PFC subjected to EUS-guided drainage using biflanged metal stents (BFMS) or double-pigtail plastic stents (DPPS) were compared for technical success, clinical success, duration of the procedure, need for intensive care unit stay, duration of intensive care unit stay, ventilator need, resolution of OF, the duration for resolution of OF, complications, need for salvage percutaneous drainage or surgery and mortality. A subgroup of patients having infected WON with/without OF were analyzed separately.

RESULTS

Among 120 patients (84.6% males) with PFC (108 WON, 22 pseudocyst) who underwent EUS-guided drainage, there was no difference in outcome parameters in BFMS and DPPS groups. Among patients with WON, clinical success was significantly higher (96.2% vs. 81.8%, P=0.04), with significantly shorter hospital stay (6 vs. 10 d) and procedure duration (17.18±4.6 vs. 43.6±9.7 min, P<0.0001) in the BFMS group. Among patients with infected WON with/without OF, the clinical success was significantly higher (100% vs. 73.9%, P=0.02), and the duration of the procedure was significantly lower (16.28±4.4 vs. 44.39±10.7, P<0.0001) in BFMS compared with DPPS group.

CONCLUSION

EUS-guided drainage of WON using BFMS scores over DPPS. In patients having infected WON with/without OF, BFMS may be preferred over DPPS.

Radiologic Predictors of Increased Number of Necrosectomies During Endoscopic Management of Walled-off Pancreatic Necrosis

GOALS

No established methods exist to predict who will require a higher number of endoscopic necrosectomy sessions for walled-off necrosis (WON). We aim to identify radiologic predictors for requiring a greater number of necrosectomy sessions. This may help to identify patients who benefit from aggressive endoscopic management.

MATERIALS AND METHODS

This is a multicenter retrospective study of patients with WON at 3 tertiary care centers. WON characteristics on preintervention computed tomography imaging were evaluated to determine if they were predictive of requiring more endoscopic necrosectomy.

RESULTS

A total of 104 patients were included. Seventy patients (67.3%) underwent endoscopic necrosectomy, with median of 2 necrosectomies. WON largest transverse diameters (P=0.02), largest coronal diameters (P=0.01), necrosis pattern [likelihood ratio (LR)=17.85, P<0.001], spread (LR=11.02, P=0.01), hemorrhage (LR=8.64, P=0.003), and presence of disconnected pancreatic duct (LR=6.80, P=0.01) were associated with undergoing ≥2 necrosectomies. Patients with septations/loculations were significantly less likely to undergo ≥2 necrosectomies (LR=4.86, P=0.03).

CONCLUSIONS

Several computed tomography radiologic features were significantly associated with undergoing ≥2 necrosectomies. These could help identify patients who will undergo a higher number of endoscopic necrosectomy sessions.

Outcomes of Endoscopic Drainage in Children with Pancreatic Fluid Collections: A Systematic Review and Meta-Analysis

PURPOSE

Endoscopic drainage is an established treatment modality for adult patients with pancreatic fluid collections (PFCs). Available data regarding the efficacy and safety of endoscopic drainage in pediatric patients are limited. In this systematic review and meta-analysis, we aimed to analyze the outcomes of endoscopic drainage in children with PFCs.

METHODS

A literature search was performed in Embase, PubMed, and Google Scholar for studies on the outcomes of endoscopic drainage with or without endoscopic ultrasonography (EUS) guidance in pediatric patients with PFCs from inception to May 2021. The study's primary objective was clinical success, defined as resolution of PFCs. The secondary outcomes included technical success, adverse events, and recurrence rates.

RESULTS

Fourteen studies (187 children, 70.3% male) were included in this review. The subtypes of fluid collection included pseudocysts (60.3%) and walled-off necrosis (39.7%). The pooled technical success rates in studies where drainage of PFCs were performed with and without EUS guidance were 95.3% (95% confidence interval [CI], 89.6-98%; I ²=0) and 93.9% (95% CI, 82.6-98%; I ²=0), respectively. The pooled clinical success after one and two endoscopic interventions were 88.7% (95% CI, 82.7-92.9%; I ²=0) and 92.3% (95% CI, 87.4-95.4%; I ²=0), respectively. The pooled rate of major adverse events was 6.3% (95% CI, 3.3-11.4%; I ²=0). The pooled rate of recurrent PFCs after endoscopic drainage was 10.4% (95% CI, 6.1-17.1%; I ²=0).

CONCLUSION

Endoscopic drainage is safe and effective in children with PFCs. However, future studies are required to compare endoscopic and EUS-guided drainage of PFCs in children.

Management of pancreatic fluid collections

Pancreatic fluid collections often develop as a complication of acute pancreatitis but can be seen in a variety of conditions including chronic pancreatitis, trauma, malignancy or post-operatively. It is important to classify a pancreatic fluid collection in order to optimize treatment strategies and management. Most interventions are targeted towards the management of delayed complications of pancreatitis, including pancreatic pseudocysts and walled-off necrosis (WON), which often develop days to weeks after the initial episode of pancreatitis. Surgical, percutaneous, and endoscopic interventions are all possible methods for treatment of pancreatic fluid collections, however endoscopic drainage with endoscopic ultrasound has become first-line. Advances within endoscopic drainage strategies have also led to innovative changes in the specific stents used for treatment, with possible options including double pigtail plastic stents, fully covered self-expanding metal stents and lumen-apposing metal stents (LAMS).

Endoscopic Transmural Drainage and Necrosectomy in Acute Necrotizing Pancreatitis: A Review

Acute necrotizing pancreatitis occurs in 10%–20% of patients with acute pancreatitis (AP) which is one of the most important acute abdominal diseases that require hospital admission. Pancreatic necrosis is also associated with high mortality and morbidity. In the past 20 years, the treatment of pancreatic necrosis has shifted from open necrosectomy to minimally invasive techniques, such as endoscopic interventions. With the development of endoscopic techniques, the safety and effectiveness of endoscopic interventions have improved, but there exist several unresolved problems. Currently, there is no unified standard approach for endoscopic treatment of pancreatic necrosis that takes into account local expertise, anatomical features of necrosis, patients’ preferences, and comorbidity profile. We reviewed the current status of endoscopic therapy for acute necrotizing pancreatitis, focusing on the new endoscopic drainage technique and necrosectomy protocol.

Hydrogen peroxide assisted endoscopic necrosectomy for walled-off pancreatic necrosis: A systematic review and meta-analysis

BACKGROUND AND AIMS

Endoscopic necrosectomy (EN) is the preferred approach for management of symptomatic or infected walled-off pancreatic necrosis (WOPN). Hydrogen peroxide (H₂O₂) has been reported to be a good adjunctive therapy for EN. We performed a systematic review and meta-analysis to evaluate effectiveness and safety of H₂O₂ assisted EN for WOPN.

METHODS

A comprehensive search of multiple databases (through December 2020) was performed to identify studies that reported outcomes of H₂O₂ assisted EN for WOPN. Outcomes assessed included clinical success, technical success, and adverse events.

RESULTS

A total of 454 patients with mean age (47.3 ± 7.9 years) and WOPN size (12.4 ± 3.1 cm) were included from 15 studies. The median H₂O₂ concentration was 3% (range 0.1-3%), with dilution and volume ranging from 1:1 to 10:1 and 20 ml to 1 L, respectively. The rates of technical success, clinical success and adverse events was 97.3% (95% confidence interval [CI]: 94.8-98.6, I² = 0), 89.8% (95% CI: 86.3-92.5, I² = 0) and 17.9% (95% CI: 12.6-24.7, I² = 38), respectively. The most common adverse event was bleeding (7.1%) followed by stent migration (5.3%). On meta-regression, WOPN size, patient age, use of metal stent, number of necrosectomies and transgastric access were not significant predictor for technical success, clinical success or adverse events.

CONCLUSION

H₂O₂ assisted EN is effective and safe for management of WOPN. Its use may be encouraged, and future randomized controlled studies are needed to study the optimal technique, concentration and best predictors of success.

Clinical Practice Guidelines for the Endoscopic Management of Peripancreatic Fluid Collections

Endoscopic ultrasonography-guided intervention has gradually become a standard treatment for peripancreatic fluid collections (PFCs). However, it is difficult to popularize the procedure in Korea because of restrictions on insurance claims regarding the use of endoscopic accessories, as well as the lack of standardized Korean clinical practice guidelines. The Korean Society of Gastrointestinal Endoscopy (KSGE) appointed a Task Force to develope medical guidelines by referring to the manual for clinical practice guidelines development prepared by the National Evidence-Based Healthcare Collaborating Agency. Previous studies on PFCs were searched, and certain studies were selected with the help of experts. Then, a set of key questions was selected, and treatment guidelines were systematically reviewed. Answers to these questions and recommendations were selected via peer review. This guideline discusses endoscopic management of PFCs and makes recommendations on Indications for the procedure, pre-procedural preparations, optimal approach for drainage, procedural considerations (e.g., types of stent, advantages and disadvantages of plastic and metal stents, and accessories), adverse events of endoscopic intervention, and procedural quality issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This will be revised as necessary to address advances and changes in technology and evidence obtained in clinical practice and future studies.

Clinical Practice Guidelines for the Endoscopic Management of Peripancreatic Fluid Collections

Endoscopic ultrasonography-guided intervention has gradually become a standard treatment for peripancreatic fluid collections (PFCs). However, it is difficult to popularize the procedure in Korea because of restrictions on insurance claims regarding the use of endoscopic accessories, as well as the lack of standardized Korean clinical practice guidelines. The Korean Society of Gastrointestinal Endoscopy appointed a Task Force to develop medical guidelines by referring to the manual for clinical practice guidelines development prepared by the National Evidence-Based Healthcare Collaborating Agency. Previous studies on PFCs were searched, and certain studies were selected with the help of experts. Then, a set of key questions was selected, and treatment guidelines were systematically reviewed. Answers to these questions and recommendations were selected via peer review. This guideline discusses endoscopic management of PFCs and makes recommendations on Indications for the procedure, pre-procedural preparations, optimal approach for drainage, procedural considerations (e.g., types of stent, advantages and disadvantages of plastic and metal stents, and accessories), adverse events of endoscopic intervention, and procedural quality issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This will be revised as necessary to address advances and changes in technology and evidence obtained in clinical practice and future studies. (Gut Liver 2021;15:-693)

Management of walled-off necrosis with nasocystic irrigation with hydrogen peroxide versus biflanged metal stent: randomized controlled trial

Background and study aims  Walled-off necrosis (WON) is a known complication of acute necrotizing pancreatitis (ANP). There is no study comparing nasocystic irrigation with hydrogen peroxide (H ₂ O ₂ ) versus biflanged metal stent (BMS) in the management of WON. The aim of this study was to compare the clinical efficacy of both the treatment strategies. Patients and methods  This study was conducted on patients with symptomatic WON who were randomized to nasocystic irrigation with H ₂ O ₂ (Group A) and BMS placement (Group B). Primary outcomes were clinical and technical success while secondary outcomes were procedure time, adverse events, need for additional procedures, duration of hospitalization, and mortality. Results  Fifty patients were randomized into two groups. Group A (n = 25, age 37.8 ± 17.6 years, 16 men) and Group B (n = 25, age 41.8 ± 15.2 years, 17 men). There were no significant differences in baseline characteristics between the two groups. The most common etiology of pancreatitis was alcohol, observed in 27 (54 %) patients. Technical success (100 % vs 96 %, P  = 0.98), clinical success (84 % vs 76 %, P  = 0.76), requirement of additional procedures (16 % vs 24 %, P  = 0.70) and adverse events (4 vs 7, P  = 0.06) were comparable in both the groups. The duration to clinical success (34.4 ± 12 vs 14.8 ± 10.8 days, P  = 0.001) and procedure time (36 ± 15 vs 18 ± 12 minutes, P  = 0.01) were longer in Group A compared to Group B. Conclusions  Nasocystic irrigation with H ₂ O ₂ and BMS are equally effective in the management of WON but time to clinical success and procedure time is longer with nasocystic irrigation.

Non-compliance to practice guidelines still exist in the early management of acute pancreatitis: Time for reappraisal?

INTRODUCTION

Earlier national surveys on the management of acute pancreatitis (AP) had reported non-compliance to practice guidelines. In the past decade, several guidelines were revised based on new evidence. In this multicenter international survey, we aimed to evaluate the practice patterns of early management of AP and compliance to the revised treatment guidelines across different disciplines and practice environments.

METHODS

A structured questionnaire was sent via email to a target population of 654 that constituted of medical and surgical gastroenterologists, physicians and general surgeons, paediatricians from academic and non-academic centres across 30 countries. Other than demographic variables, the questionnaire contained items pertaining to early management of AP, such as, assessment at admissions and within first 72 h s, details regarding analgesics, IV hydration, oral/enteral feeding and antibiotic use.

RESULTS

The response rate was 46.2% and after exclusions, a total of 297 participant's responses were analysed. Majority of the participants were from Asia, followed by Europe and the Americas. 181 (60.9%) claimed to follow practice guidelines, out of which 59 (32.6%) followed more than one. On further probing, only 41.9% were actually compliant to feeding and 59.7% to antibiotic guidelines. Even though participants opted for aggressive hydration, early feeding and avoidance of prophylactic antibiotics, there were non-compliance and discrepancies in titration of fluid therapy, indications of feeding and antibiotic use.

DISCUSSION

Discrepancies and non-compliance still appear to exist in the early management of AP due to lack of strong evidence. We discuss ways that could improve compliance to the existing guidelines until stronger evidence comes to the fore.

Direct Endoscopic Necrosectomy With and Without Hydrogen Peroxide for Walled-off Pancreatic Necrosis: A Multicenter Comparative Study

INTRODUCTION

Endoscopic necrosectomy has emerged as the preferred treatment modality for walled-off pancreatic necrosis. This study was designed to evaluate the safety and efficacy of direct endoscopic necrosectomy with and without hydrogen peroxide (H2O2) lavage.

METHODS

Retrospective chart reviews were performed for all patients undergoing endoscopic transmural management of walled-off pancreatic necrosis at 9 major medical centers from November 2011 to August 2018. Clinical success was defined as the resolution of the collection by imaging within 6 months, without requiring non-endoscopic procedures or surgery.

RESULTS

Of 293 patients, 204 met the inclusion criteria. Technical and clinical success rates were 100% (204/204) and 81% (166/189), respectively. For patients, 122 (59.8%) patients had at least one H2O2 necrosectomy (H2O2 group) and 82 (40.2%) patients had standard endoscopic necrosectomy. Clinical success was higher in the H2O2 group: 106/113 (93.8%) vs 60/76 (78.9%), P = 0.002. On a multivariate analysis, the use of H2O2 was associated with higher clinical success rate (odds ratio 3.30, P = 0.033) and earlier resolution (odds ratio 2.27, P < 0.001). During a mean follow-up of 274 days, 27 complications occurred. Comparing procedures performed with and without H2O2 (n = 250 vs 183), there was no difference in post-procedure bleeding (7 vs 9, P = 0.25), perforation (2 vs 3, P = 0.66), infection (1 vs 2, P = 0.58), or overall complication rate (n = 13 [5.2%] vs 14 [7.7%], P = 0.30).

DISCUSSION

H2O2-assisted endoscopic necrosectomy had a higher clinical success rate and a shorter time to resolution with equivalent complication rates relative to standard necrosectomy.See the visual abstract at http://links.lww.com/AJG/B714.(Equation is included in full-text article.).

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

Background

To 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).

Methods

Patients 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.

Results

387 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.

Conclusion

BFMS with a “step-up approach” and LAMS with scheduled DEN are both safe and effective for EUS-guided drainage/debridement of WON.

Predictors of the need for necrosectomy in patients with walled-off pancreatic necrosis treated with lumen apposition metal stents

BACKGROUND AND AIMS

Endoscopic necrosectomy through lumen apposition metal stents (LAMS) is increasingly being used for complicated walled-off pancreatic necrosis (WOPN), but the need for necrosectomy after stent placement is not well understood. The aim of this study was to evaluate clinical, endoscopic, and radiologic predictors of the need for necrosectomy in patients treated with LAMS.

METHODS

We retrospectively reviewed patients with WOPN treated with LAMS from 2014 to 2017. Necrosectomy was performed only in patients who had recurrent fever or hemodynamic instability during follow-up. Univariate and multivariate analyses were performed.

RESULTS

We included 15 patients, 67% men and median age was 75 (54-76) years. Two (13%) presented adverse events, one immediate and one delayed. In the first case, the stent migrated to the gastric cavity during deployment but was relocated in the same procedure. In the second case, the patient presented bleeding on day 36 due to a pseudoaneurysm that was successfully treated with embolization. Clinical success was 100%, but five patients (33%) required endoscopic necrosectomy (4 mechanical and 1 irrigation) and one (7%) required surgical necrosectomy of distant collections. The percentage of necrosis in the collection detected in a previous CT scan (45 [35-66]% vs 10 [5-17]%) was the only factor to predict the need for necrosectomy in the multivariate analysis (OR 1.18 [1.01-1.39]).

CONCLUSION

LAMS is efficient to treat WOPN but more than a third will need necrosectomy. The percentage of necrosis in the collection detected in the CT scan seems to predict the need for necrosectomy.

A novel value-based scoring system for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a single-centre comparative study of plastic and lumen-apposing metal stents (NOVA study)

OBJECTIVE

Healthcare resources are finite. Value in healthcare can be defined as patient health outcomes achieved per monetary unit spent. Attempts have been made to quantify the value of luminal endoscopy, but there is little in the medical literature describing the value of the complex therapeutic endoscopic activity. This study aimed to characterise the value of endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFCs) with either plastic or lumen-apposing metal stents (LAMSs).

METHODS

This is a single-centre, retrospective-prospective comparative study of 39 patients, who underwent EUS-guided PFC drainage between 2009 and 2018. Procedure value was calculated using the formula Q/(T/C), where Q is the quality of procedure adjusted for complications, T procedure duration and C is the complexity adjustment. Quality and complexity were estimated on a 1-4 Likert scale based on the American Society for Gastrointestinal Endoscopy criteria. Time (in minutes) was recorded from the patient entering and leaving the procedure room. Endoscopy time calculated from procedure time was considered a surrogate marker of cost as individual components of procedure cost were not itemized.

RESULTS

Of 39 identified patients who underwent EUS-guided PFC drainage, 11 received double pigtail plastic stents (DPPSs) and 28 received LAMSs. The two groups were comparable in age, gender and aetiology. Nearly 40% of the LAMS interventions were considered high value but only 11% of the plastic stent interventions achieved the same. The difference predominantly was due to a higher rate of complications and longer procedure time.

CONCLUSION

In this single-centre study, EUS-guided PFC drainage using LAMS was found to be a higher value procedure compared to the use of DPPS.

Effectiveness of early endoscopic ultrasound-guided drainage for postoperative fluid collection

BACKGROUND

Postoperative abdominal fluid collections (PAFCs) are a potentially fatal complication of pancreatobiliary surgery. Endoscopic ultrasound (EUS)-guided drainage has recently been shown to be effective in treating PAFCs of more than 4 weeks old. Little is currently known, however, regarding the EUS-guided drainage of PAFCs of less than 4 weeks. This study assessed the efficacy and safety of the early drainage (< 4 weeks) of PAFCs via EUS guidance.

METHODS

The data of patients who had undergone EUS-guided PAFC drainage between July 2008 and January 2018 were retrospectively analyzed. Data of EUS-guided PAFC drainage were obtained from prospectively collected EUS database of our institute and reviewed of patients' clinical parameters based on electrical medical record.

RESULTS

A total of 48 patients who had undergone EUS-guided PAFC drainage within 4 weeks of pancreatobiliary surgery were enrolled. The indications of procedure included abdominal pain (n = 27), fever (n = 18), leukocytosis (n = 2), and increased size of PAFC during external tube drainage (n = 1). Technical success was achieved in all cases, and the clinical success rate was 95.8% (46/48). Four patients underwent secondary procedures. The median period from surgery to EUS-guide drainage was 14 days (Interquartile range [IQR] 10-16), and median time to resolution was 23.5 days (IQR 8.5-33.8). Adverse events occurred in two cases that were developed intracystic bleeding and were successfully resolved by arterial coil embolization.

CONCLUSIONS

Early EUS-guided drainage is a technically feasible, effective, and safe method in patients who have developing PAFCs within 4 weeks of pancreatobiliary surgery.

Evaluation of hydrogen peroxide-assisted endoscopic ultrasonography-guided necrosectomy in walled-off pancreatic necrosis: A single-center experience

Hydrogen peroxide is a liquid that functions in mechanical removal of the necrotic tissue via the elimination of tissue debris.In this study, we aimed to evaluate the effectiveness of the use of hydrogen peroxide in necrosectomy treatment of walled-off pancreatic necrosis.Records of 24 patients who were diagnosed with pancreatic necrosis or walled-off pancreatic necrosis and underwent endoscopic necrosectomy (EN) were retrospectively assessed. Patients were divided into 2 groups; hydrogen peroxide used for treatment or not used, and these 2 groups were compared.A total of 24 patients underwent endoscopic intervention for walled-off pancreatic necrosis. Procedural success was comparable between the 2 groups. During the post-procedural follow-up, the duration of the hospital stay, recurrence, and complication rates were found to be similar in both groups. The mean number of the endoscopic interventions was significantly lower in the hydrogen peroxide group (4.2 ± 1.4 vs 6.1 ± 4.2; P = .01).The use of hydrogen peroxide for EN in walled-off pancreatic necrosis patients seems to have similar efficiency and safety. However, it can be said that the use of hydrogen peroxide could reduce the number of endoscopic procedures.

The role of solid debris in endoscopic ultrasound-guided drainage of walled-off necrosis: A large cohort study

BACKGROUND AND AIM

The effect of solid debris on walled-off necrosis (WON) drainage remains unknown. Our study evaluated the role of solid debris in endoscopic ultrasound (EUS)-guided drainage of WON compared lumen-apposing metal stent (LAMS) with double-pigtail plastic stent (DPPS).

METHODS

We retrospectively evaluated consecutive patients with WON who underwent EUS-guided drainage in our endoscopic center over a 9-year period. The amount of solid debris in WON was assessed with computed tomography or magnetic resonance imaging and EUS images.

RESULTS

From 2011 to 2019, 84 WON patients were included. In WON with < 20% solid debris, the short-term clinical success of LAMSs (96.8%) was significantly higher than DPPSs (66.7%) (P = 0.03), and LAMSs were safer than DPPSs with less early adverse events (P = 0.02) and late adverse events (P = 0.03). On multivariable analysis, DPPS (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.04-0.65; P = 0.01) and solid debris > 40% (OR, 0.11; 95% CI, 0.02-0.62; P = 0.01) were the predictors for failure of resolution of WON after adjusting for age and cyst size. The number of DPPSs used was significantly higher than LAMSs in managing WONs (P < 0.001).

CONCLUSION

For WON with < 20% solid debris, LAMSs might superior to DPPSs in terms of efficacy and safety.

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.

Clinical practice of acute pancreatitis in Japan: An analysis of nationwide epidemiological survey in 2016

BACKGROUND

To provide updates on clinical practice of acute pancreatitis (AP) in Japan, we conducted a nationwide epidemiological survey.

METHODS

This study consisted of a two-staged survey; the number of AP patients was estimated by the first-stage survey and their clinical features were examined by the second-stage survey. We surveyed AP patients who had visited hospitals in 2016.

RESULTS

The estimated number of AP patients in 2016 was 78,450, with an overall incidence of 61.8 per 100,000 persons. We obtained detailed clinical information of 2994 AP patients, including 706 (23.6%) severe cases classified according to the Japanese severity criteria. The male-to-female sex ratio was 2.0, and the mean age at onset was 59.9 years in males and 66.5 years in females. Alcohol was the most common etiology (42.8%) in males and gallstones in females (37.7%). The AP-associated mortality was 6.1% in severe AP cases, which was decreased by 40% compared to the 2011 survey. Antibiotics were administered to most cases, with carbapenem being frequently used. Enteral nutrition was given in 31.8% of severe cases, but majority cases received after 48 h. Among the 107 patients who received intervention for walled-off necrosis, five patients received surgery-first approach, 66 received endoscopic ultrasound-guided transluminal drainage, and 19 underwent step-up approach.

CONCLUSIONS

We clarified the current status of AP in Japan including the significant reduction of mortality in severe cases, shift to endoscopic approaches for walled-off necrosis, and poor compliance of the recommendations in the guidelines including management of enteral nutrition and antibiotic administration.

Are Lumen-Apposing Metal Stents More Effective Than Plastic Stents for the Management of Pancreatic Fluid Collections: An Updated Systematic Review and Meta-analysis

Background and Aims

Recently, a new type of metal stent, named lumen-apposing metal stents (LAMS), has been designed to manage pancreatic fluid collections (PFC), and a few studies have reported its efficacy and safety. Therefore, we conducted this meta-analysis to investigate the role of LAMS for PFC.

Methods

We searched the studies from PubMed, MEDLINE, Embase, and Cochrane databases from inception to May 2019. We extracted the data and analyzed the technical success, clinical success, and adverse events of LAMS to evaluate its efficacy and safety.

Results

Twenty studies with 1534 patients were included. The pooled technical success, clinical success, and adverse event rates of LAMS for PFC were 96.2% (95% confidence interval (CI): 94.6%-97.4%), 86.8% (95% CI: 83.1%-89.8%), and 20.7% (95% CI: 16.1%-26.1%), respectively. Eight studies including 875 patients compared the clinical outcomes of LAMS with plastic stents. The pooled risk ratio (RR) of technical success and clinical success for LAMS and plastic stent was 1.01 (95% CI: 0.98-1.04, P = 0.62) and 1.06 (95% CI: 1.01-1.12, P = 0.03), respectively. As for the overall adverse events, the pooled RR was 1.51 (95% CI: 0.67-3.44, P = 0.32).

Conclusions

Our current study revealed that LAMS has advantages over plastic stents for PFC, with higher clinical success rate and lower complication rate of infection and occlusion.

Clinical and morphological consequences of permanent indwelling transmural plastic stents in disconnected pancreatic duct syndrome

Background:

Long-term indwelling transmural stents in patients with walled-off necrosis (WON) and disconnected pancreatic duct syndrome (DPDS) is an effective strategy to decrease risk of recurrence of pancreatic fluid collection (PFC). However, long-term studies on the safety and efficacy of this strategy are lacking.

Methods:

Retrospective analysis of database of patients with WON treated with endoscopic transmural drainage over the past 8 years was done to identify patients with DPDS and indwelling transmural stents for >3 years.

Results:

During the past 8 years, 56 patients with indwelling transmural stent for >3 years were identified and 67.85% of these patients had 10 Fr stents and 32.15% of patients had 7 Fr stents. On follow-up, 5 (8.9%) patients had pancreatic pain with one patient (1.78%) developing recurrence of PFC despite stent being in situ. Two (3.5%) patients had asymptomatic spontaneous external migration of the transmural stent. Fourteen (25%) patients developed diabetes. Two (3.5%) patients developed local complications due to indwelling stent (stent eroded into descending colon in one patient and stent-induced parenchymal calcification in the other). Forty-eight (85.7%) patients underwent EUS on follow-up and disconnected pancreas revealed ≥5 criteria for the diagnosis of chronic pancreatitis in 15 (31.25%) patients.

Conclusions:

Long-term indwelling transmural plastic stents in patients with WON and DPDS are safe and effective with minimal complications. Despite the presence of stents, disconnected pancreas develops morphological changes resembling chronic pancreatitis in one-third patients and clinical consequences of these changes need to be further evaluated.

Prospective multicenter international study on the outcomes of a newly developed self-approximating lumen-apposing metallic stent for drainage of pancreatic fluid collections and endoscopic necrosectomy

BACKGROUND

A novel self-approximating lumen-apposing metallic stent (LAMS; Niti-S Spaxus, Taewoong Medical, Gyeonggi-do, Korea) has recently become available. The aim of the present study was to evaluate the outcomes for drainage of pancreatic fluid collections (PFC).

METHODS

This was a prospective international multicentered study conducted in six high-volume institutions across Asia. Consecutive patients suffering from pancreatic pseudocyst or walled-off pancreatic necrosis (WOPN) requiring endoscopic ultrasonography-guided drainage were recruited. Outcomes included technical and clinical success, adverse events, procedural events, interventions through the stent and recurrence rates.

RESULTS

Between August 2016 and November 2017, 59 patients were recruited to this study. Thirty-nine patients (66.1%) had WOPN and mean (SD) size of PFC was 11.5 (5.1) cm. Technical and clinical success rates were 100%. Mean (SD) procedural time was 35.0 (17.2) minutes. Sixteen-millimeter stents were used in 66.1% of the patients. Fifty-four sessions of necrosectomy were carried out with the stent in situ in 17 patients. Stent-related adverse event (AE) rate was 6.8%. Three patients (5.1%) suffered from bleeding after stenting and one required angiographic embolization. Two patients (3.4%) suffered from recurrence during a mean (SD) follow-up time of 325.6 (355.5) days. There were no differences in outcomes between those with pseudocysts or WOPN except for the duration of hospital stay (P = 0.012).

CONCLUSION

Use of a self-approximating LAMS for drainage of PFC was safe and effective. Endoscopic necrosectomy could be carried out through the stent with ease. The device was associated with a low rate of stent-related AE.

International multicenter comprehensive analysis of adverse events associated with lumen-apposing metal stent placement for pancreatic fluid collection drainage

BACKGROUND AND AIMS

High rates of technical and clinical success were reported for lumen-apposing metal stent (LAMS) placement for peripancreatic fluid collection (PFC) drainage. However, data on the adverse event (AE) rates are heterogeneous. The aim of this study was to evaluate the incidence, severity, management, and risk factors of AEs related to the use of LAMSs for drainage of PFCs in a large cohort of patients.

METHODS

This is a multicenter, international, retrospective review from 15 centers of all patients who underwent placement of LAMSs for the management of PFCs. A nested case-control study was conducted in patients with (case) or without (control) AEs.

RESULTS

Three hundred thirty-three procedures in 328 patients were performed (5 patients treated with 2 LAMSs). Technical success was achieved in 321 patients (97.9%). Three hundred four patients were finally included in the study (7 excluded for lost to follow-up information; 10 excluded for deaths unrelated to LAMSs). The rate of clinical success was 89.5%. Seventy-nine LAMS-related AEs occurred in 74 of 304 patients (24.3%), after a mean time of 25.3 days (median, 18 days; interquartile range, 6-30) classified as 20 (25.3%) mild, 54 (68.4%) moderate, or 5 (6.3%) severe. On multivariable analysis compared with control subjects, cases were more likely to have walled-off necrosis (WON) versus pancreatic pseudocysts (odds ratio, 2.18; 95% confidence interval, 1.09-4.46; P = .028), whereas cases were less likely to have undergone tract (balloon) dilation (yes vs no; odds ratio, .47; 95% confidence interval, .22-.93; P = .034).

CONCLUSIONS

Data from this large international retrospective study confirm that the use of LAMSs for management of PFCs has excellent technical and good clinical success rates. The rate of AEs, however, is not negligible and should be carefully considered before using these stents for drainage of PFCs and in particular for WON. Further prospective studies are needed to confirm these findings. (Clinical trial registration number: NCT03544008.).