Hydrogen peroxide-assisted endoscopic necrosectomy for walled-off pancreatic necrosis: a dual center pilot experience

Supportive treatment during the periprocedural period of endoscopic treatment for pancreatic fluid collections: a critical review of current knowledge and future perspectives

Pancreatic fluid collections (PFCs) commonly develop as complications of acute pancreatitis and ductal disruption due to chronic pancreatitis. In the revised Atlanta classification, PFCs were classified based on the presence of necrosis and duration following the onset of acute pancreatitis. Interventions are required in cases of symptomatic pancreatic pseudocysts or walled-off necrosis (WON). In the management of these PFCs, endoscopic ultrasound-guided transluminal drainage and subsequent direct endoscopic necrosectomy for WON are increasingly utilized as less invasive treatment modalities compared to surgical debridement. To date, researchers have focused predominantly on the technical aspects of endoscopic therapy for symptomatic PFCs. Given the poor physical condition of patients receiving endoscopic treatment for PFCs, systemic support may have a substantial impact on the short- and long-term outcomes of these patients. A multidisciplinary approach is required to improve the clinical outcomes of patients with infected PFCs and their associated comorbidities. However, non-interventional support during the periprocedural period of endoscopic treatment of PFCs has not been fully discussed, and there have been considerable variations in the selection of treatment options between endoscopists and centers. To address these unmet needs in the clinical management of PFCs and promote future research to improve the clinical outcomes, we conducted a review of the literature within a multicenter consortium of expert endoscopists with specific expertise in the endoscopic treatment of PFCs. In this review, we summarize the current evidence on non-interventional supportive care (e.g., continuous lavage, medications, nutritional support, and antimicrobials) and propose potential topics for future research.

Drainage of Complex Walled-Off Pancreatic Fluid Collections in LAMS Era: A Multicenter Study

BACKGROUND

The lumen-apposing metal stent (LAMS) has been increasingly used for EUS-guided drainage of symptomatic walled-off pancreatic fluid collection (WOPFC) in recent years. Nevertheless, some WOPFCs may require additional drainage methods including another LAMS as a result of complexity of the lesions. This current study aimed to compare clinical parameters of patients with complex WOPFC requiring LAMS with additional methods (complex WOPFC: group A) versus single LAMS alone (noncomplex WOPFC; group B).

METHOD

Medical records of patients with complex (group A) versus noncomplex WOPFCs (group B) were reviewed and compared in three centers in Thailand and Malaysia, between January 2016 to December 2020.

RESULT

31 patients with WOPFCs were recruited. 6 of 31 (19%) patients were in group A. Multivariate analysis showed that the maximal diameter of WOPFCs in group A was significantly larger than that of group B (18 ± 6 versus 13 ± 3 cm in diameter, respectively, p = 0.021). Solid component proportion was higher in group A versus B (35.8% versus 17.8%, respectively, p = 0.025). The prevalence of pancreatic duct leakage was significantly higher in group A (67% versus 20%, p = 0.23). The need of direct endoscopic necrosectomy (DEN) and the number of DEN sessions were higher in group A versus B (100% vs. 48%, p = 0.020 and 3.5 vs 0 p = 0.031, respectively).

CONCLUSIONS

Complex WOPFC had larger diameter of lesions, higher proportion of solid component, higher prevalence of pancreatic duct leakage, and higher number of DEN is required than group noncomplex lesions. Trial Registration. This trial is registered with TCTR20180223004.

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.

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).

Novel Resection System for Direct Endoscopic Necrosectomy of Walled-Off Pancreas Necrosis: Have We Conquered the Final Frontier?

Surgical necrosectomy has been the traditional management for pancreatic necrosis and is done using blunt dissection. However, lack of dedicated endoscopic accessories has been a major limitation in direct endoscopic necrosectomy (DEN). Standard endoscopic accessories cannot effectively remove large necrotic material. Also, diameter of instrument channel of the endoscope limits the ability to use large-diameter graspers that can remove large chunks of necrotic material. In this news, we discuss a recent study that has evaluated a new powered endoscopic debridement system for DEN.

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.

Direct Endoscopic Necrosectomy: Timing and Technique

Walled-off pancreatic necrosis (WOPN) is one of the local complications of acute pancreatitis (AP). Several interventional techniques have been developed over the last few years. The purpose of this narrative review is to explore such methodologies, with specific focus on endoscopic drainage and direct endoscopic necrosectomy (DEN), through evaluation of their indications and timing for intervention. Findings indicated how, after the introduction of lumen-apposing metal stents (LAMS), DEN is becoming the favorite technique to treat WOPN, especially when large solid debris or infection are present. Additionally, DEN is associated with a lower adverse events rate and hospital stay, and with improved clinical outcome.

Comparative outcomes of endoscopic ultrasound-guided lumen-apposing mental stents drainage for pancreatic pseudocysts and walled-off necrosis: Case series and meta-analysis

Background

Endoscopic ultrasound (EUS)-guided transmural drainage for pancreatic fluid collections (PFCs) has become the first-line treatment with quicker recovery and more minor injury compared with surgery and percutaneous drainage. The efficacy of stents implantation and drainage for different PFCs remains controversial, especially lumen-apposing metal stents (LAMS). This study aimed to compare the efficacy and safety of LAMS drainage for pancreatic pseudocysts (PPC) and walled-off necrosis (WON).

Methods

A meta-analysis was performed for LAMS drainage for WON and PPC by systematically searching PubMed, Cochrane, and Embase databases from January 2010 to January 2020. From 2017 to 2019, 12 patients who were treated with LAMS drainage for PFCs in our medical center were also reviewed and included in this study.

Results

Combining 11 copies of documents with the data from our medical center, a total of 585 patients with PFCs were enrolled in this meta-analysis, including 343 patients with WON and 242 with PPC. The technical success rate in WON is not significantly different from that of PPC (P = 0.08 > 0.05). The clinical success of LAMS placement was achieved in 99% vs 89% in PPC and WON, respectively (RR = 0.92, 95% CI: 0.86-0.98, P = 0.01 < 0.05). The further intervention of direct endoscopic necrosectomy was required by 60% of patients in WON group. There was no significant difference in the incidence of adverse events, including infection, bleeding, stent migration and stent occlusion, after LAMS placement between WON and PPC.

Conclusions

Endoscopic ultrasound-guided LAMS for PFCs are feasible, effective with preferable technical and clinical success rates. The clinical effect of LAMS on PPC is slightly better than that of WON, but its adverse reactions still need to be verified in a large-sample prospective study.

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.

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.).

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 endoscopic therapy in the minimally invasive management of pancreatic necrosis

Pancreatic necrosis is among the most frequently encountered local complications of acute pancreatitis and associates with severe disease. Infected pancreatic necrosis further enhances the risk for morbidity and mortality. Pancreatic fluid collections that result from pancreatic necrosis evolve from acute necrotic collections to walled off necrosis and are defined by their distinct characteristics on cross sectional imaging. A variety of interventions spanning multiple disciplines are available for the drainage and debridement of pancreatic necrosis. Prospective, randomized trials have identified management strategies that incorporate minimally invasive interventions as having the best outcomes for patients with symptomatic pancreatic necrosis. The scientific literature has confidently positioned endoscopic drainage and necrosectomy among the most effective interventions for patients with symptomatic walled off necrosis. Innovations such as the use of metallic stents, chemical debridement and multiple modalities for drainage of pancreatic necrosis show promise in improving outcomes for patients managed with endoscopic interventions.

Advances in Interventional Endoscopic Ultrasound (EUS): A Technical Review

Endoscopic ultrasound (EUS) has become the therapeutic intervention of choice for multiple diseases and continues to evolve rapidly. Its increasing use has allowed the development and adaptation of multiple, revolutionary devices and tools. Currently, there is paucity of randomized clinical trials evaluating multiple EUS-guided interventions and the vast majority of published data is heterogenous. However, the available literature on EUS-guided therapeutic interventions continues to expand and demonstrate its safety, efficacy and cost effectiveness in carefully selected patients when performed by expert endosonographers. The future of interventional EUS appears to be bright!

Management of pancreatic collections: an update

Pancreatic fluid collections frequently occur in the context of moderate and severe acute pancreatitis, and may also appear as a complication of chronic pancreatitis, pancreatic surgery or trauma. It is essential to adhere to the Atlanta classification nomenclature that subclassifies them into four categories (acute peripancreatic fluid collections, acute necrotic collections, pseudocysts, and walled-off necrosis) since it has an impact on prognosis and management. Pseudocysts and walled-off pancreatic necrosis are encapsulated pancreatic fluid collections characterized by a surrounding inflammatory wall, which typically develops three to four weeks after the onset of acute pancreatitis. Most pancreatic fluid collections resolve spontaneously and do not require intervention. However, when they become symptomatic or complicated drainage is indicated, and endoscopic ultrasound-guided drainage has become first-line treatment of encapsulated collections. Drainage of pseudocysts is relatively straightforward due to their liquid content. However, in walled-off necrosis the presence of solid necrotic debris can make treatment more challenging and therefore multidisciplinary management in experienced centers is recommended, being a step-up approach the current standard of care. In this review, we aim to address the management of pancreatic fluid collections with an especial focus on endoscopic drainage.

Endoscopic intervention in pancreatitis: perspectives from a gastroenterologist

The last decade has seen a dramatic paradigm shift for the treatment of pancreatitis and its related complications away from surgery to minimally invasive endoscopic approaches. In this review, we provide an overview of the indications, techniques and outcomes of endoscopic interventions in the management of acute and chronic pancreatitis. Emphasis is placed on drainage of pancreatic pseudocysts and treatment of pain in chronic pancreatitis.

Pancreatic fluid collections: Clinical manifestations, diagnostic evaluation and management

Pancreatic fluid collections (PFC), including pancreatic pseudocysts and walled-off pancreatic necrosis, are a known complication of severe acute pancreatitis. A majority of the PFCs remain asymptomatic and resolve spontaneously. However, some PFCs persist and can become symptomatic. Persistent PFCs can also cause further complications such as the gastric outlet, intestinal, or biliary obstruction and infection. Surgical interventions are indicated for the drainage of symptomatic sterile and infected PFCs. Management of PFCs has evolved from a primarily surgical or percutaneous approach to a less invasive endoscopic approach. Endoscopic interventions are associated with improved outcomes with lesser chances of complications, faster recovery time, and lower healthcare utilization. Endoscopic ultrasound-guided drainage of PFCs using lumen-apposing metal stents has become the preferred approach for the management of symptomatic and complicated PFCs.

Endoscopic Management of Acute Biliopancreatic Disorders

PURPOSE

Endoscopy is playing an ever-increasing role in the management of acute biliopancreatic disorders. With the management paradigm shifting away from more invasive surgical approaches, surgeons need to be aware of the treatment options available to improve patient care. Our manuscript serves to improve surgeons' knowledge and understanding of these emerging treatment modalities to expand their algorithmic approach to biliopancreatic disorders.

METHODS

Specific acute biliopancreatic disorders were identified from the literature and personal practice to create a structured review of common problems experienced by a surgeon of the gastrointestinal tract. An exhaustive literature review was performed to identify and analyze endoscopic treatment modalities for these disorders.

RESULTS

Endoscopic therapies continue to expand rapidly with a robust supportive literature. Data on endoscopic treatment strategies for acute biliopancreatic disorders demonstrate valuable improvements in outcomes in a number of these disorders.

DISCUSSION

Acute biliopancreatic disorders represent one of the most challenging pathophysiologies that a surgeon of the gastrointestinal tract may face. This manuscript represents a review of available endoscopic instrumentation as well as the author's interpretation of the current literature regarding indications and outcomes of endoscopic management for acute biliopancreatic disorders. Although this article does not supplant formal training in therapeutic endoscopy, surgeons reading this article should understand the role endoscopy plays in the management of acute biliopancreatic disorders.

Current Concepts in Severe Acute and Necrotizing Pancreatitis: An Evidence-Based Approach

The incidence of acute pancreatitis continues to rise, inducing substantial medical and social burden, with annual costs exceeding $2 billion in the United States alone. Although most patients develop mild pancreatitis, 20% develop severe and/or necrotizing pancreatitis, requiring advanced medical and interventional care. Morbidity resulting from local and systemic complications as well as invasive interventions result in mortality rates historically as high as 30%. There has been substantial evolution of strategies for interventions in recent years, from open surgery to minimally invasive surgical and endoscopic step-up approaches. In contrast to the advances in invasive procedures for complications, early management still lacks curative options and consists of adequate fluid resuscitation, analgesics, and monitoring. Many challenges remain, including comprehensive management of the entire spectrum of the disease, which requires close involvement of multiple disciplines at specialized centers.

Pancreatic necrosis: Complications and changing trend of treatment

Incidence of acute pancreatitis seems to be increasing in the Western countries and has been associated with significantly increased morbidity. Nearly 80% of the patients with acute pancreatitis undergo resolution; some develop complications including pancreatic necrosis. Infection of pancreatic necrosis is the leading cause of death in these patients. A significant portion of these patients needs surgical interventions. Traditionally, the “gold standard” procedure has been the open surgical necrosectomy, which is now being completed by the relatively lesser invasive interventions. Minimally invasive surgical (MIS) procedures include endoscopic drainage, percutaneous image-guided catheter drainage, and retroperitoneal drainage. This review article discusses the open and MIS interventions for pancreatic necrosis with each having its own respective benefits and disadvantages are covered.

Lumen apposing metal stents are superior to plastic stents in pancreatic walled-off necrosis: a large international multicenter study

Background and study aims  The use of lumen apposing metal stents (LAMS) during EUS-guided transmural drainage (EUS-TD) of pancreatic walled-off necrosis (WON) has gained popularity. Data supporting their use in WON over plastic stents (PS), however, remain scarce. The aim of this study was to compare the clinical efficacy of LAMS (Axios, Boston Scientific) with PS in WON. Patients and methods  This was a multicenter, retrospective study involving 14 centers. Consecutive patients who underwent EUS-TD of WON (2012 - 2016) were included. The primary end point was clinical success defined as WON size ≤ 3 cm within a 6-month period without need for percutaneous drainage (PCD) or surgery. Results  A total of 189 patients (mean age 55.2 ± 15.6 years, 34.9 % female) were included (102 LAMS and 87 PS). Technical success rates were similar: 100 % in LAMS and 98.9 % in PS ( P  = 0.28). Clinical success was attained in 80.4 % of LAMS and 57.5 % of PS ( P  = 0.001). Rate of PCD was similar (13.7 % LAMS vs. 16.3 % PS, P  = 0.62), while PS was associated with a greater need for surgery (16.1 % PS vs. 5.6 % LAMS, P  = 0.02). Adverse events (AEs) were observed in 9.8 % of LAMS and 10.3 % of PS ( P  = 0.90) and were rated as severe in 2.0 % and 6.9 %, respectively ( P  = 0.93). After excluding patients with < 6 months follow-up, the rate of WON recurrence following initial clinical success was greater with PS (22.9 % PS vs. 5.6 % LAMS, P  = 0.04). Conclusions  When compared to PS, LAMS in WON is associated with higher clinical success, shorter procedure time, lower need for surgery, and lower rate of recurrence.

Endoscopic management of pancreatic fluid collections

Pancreatic fluid collections (PFCs) are common complications of acute pancreatitis. Asymptomatic collections do not require drainage while symptomatic or infected collections should be drained. Drainage can be performed surgically, percutaneously, or endoscopically. Recent studies have shown that endoscopic drainage of PFCs is equivalent or superior to surgical or percutaneous drainage, with less complications. Advances in tools and technology coupled with increasing expertise in management of PFCs has resulted in minimally invasive endoscopic drainage, by endosonographic guidance, being the preferred approach. New larger diameter lumen apposing metal stents (LAMS) have simplified the process of drainage. LAMS have also made performing direct endoscopic necrosectomy for walled-off necrosis (WON) easier. Technique, duration, frequency, and tools used for direct endoscopic necrosectomy are variable. Performing PFC drainage requires adequate and fundamental knowledge of diagnostic and basic therapeutic EUS.

Endotherapy for pancreatic necrosis: An update

Approximately 20% of patients with acute pancreatitis develop pancreatic necrosis. The presence of necrosis in a pancreatic collection significantly worsens the prognosis. Pancreatic necrosis is associated with high mortality and morbidity. In the last few decades, there has been a significant revolution in the treatment of infected pancreatic necrosis. A step‐up approach has been proposed, from less invasive procedures to the operative intervention. Minimally invasive treatment modalities such as endoscopic drainage and necrosectomy, percutaneous drainage, and minimally invasive surgery have recently replaced open surgical necrosectomy as the first‐line treatment option. Endoscopic intervention for pancreatic necrosis is being increasingly performed with good success and a lower complication rate. However, techniques of endotherapy are still not uniform and vary as per local expertise, and there are still many unresolved questions with regard to the interventions in patients with pancreatic necrosis. The objective of this paper is to critically review the literature and update the concepts of endoscopic interventional therapy of pancreatic necrosis.

Endoscopic Drainage of Pancreatic Fluid Collections

Endoscopy has emerged as a mainstay in the management of pancreatic fluid collections (PFCs), representing an important advance in clinical medicine that has significantly improved the risk-benefit ratio of treating this complex patient population. While endoscopic pseudocyst drainage has generally supplanted surgical and percutaneous approaches, the optimal strategy for walled-off necrosis remains variable and multi-disciplinary despite an emerging trend from randomized trials favoring endoscopy. Although several issues pertaining to endoscopic drainage appear to have been settled - such as the use of endoscopic ultrasound - other pressing questions - including the optimal prosthesis and debridement strategy - remain unanswered, and rigorous investigation is needed. This review aims to provide an evidence-based but practical appraisal of the endoscopic drainage of PFCs through the perspective of the author, with an emphasis on relevant clinical and endoscopic considerations and important research questions.

Systematic Review of Endoscopic Cyst Gastrostomy

Since the original description of pancreatic fluid collections (PFC) in 1761 by Morgagni, their diagnosis, description, and management have continued to evolve. The mainstay of therapy for symptomatic PFCs has been the creation of a communication between a PFC and the stomach, to enable drainage. Surgical creation of these drainage conduits had been the gold standard of therapy; however, there has been a paradigm shift in recent years with an increasing role of endoscopic drainage. The techniques of endoscopic drainage have evolved from blind fluid aspiration to include endoscopic necrosectomy and the placement of lumen-apposing metal stents.

Endoscopic Management of Infected Necrotizing Pancreatitis: an Evidence-Based Approach

PURPOSE OF REVIEW

Endoscopic management of infected necrotizing pancreatitis has evolved rapidly over the past years and there have been interesting innovations in this field. This review provides an update on the most recently published literature regarding endoscopic management of infected necrotizing pancreatitis.

RECENT FINDINGS

A recent randomized trial demonstrated no difference in mortality and major morbidity between endoscopic and surgical step-up treatment of infected necrotizing pancreatitis. However, endoscopic therapy resulted in shorter hospital stay and less pancreatic fistulas. Various innovations have been investigated with the aim to further optimize endoscopic therapy, in particular lumen-apposing metal stents. While major stent-related complications were also reported, findings from recent studies indicated that their use was associated with higher resolution rates of walled-off necrosis compared to double-pigtail stents. Other innovations, such as the multiple gateway technique and dual-modality mode, can be considered for treatment of particular cases. Furthermore, research suggests that irrigation of walled-off necrosis can be performed by using a nasocystic tube and discontinuation of proton-pump inhibitors may be considered. Endoscopic treatment should be the preferred treatment modality in patients with infected necrotizing pancreatitis who are eligible for endoscopic drainage. Although data suggests that lumen-apposing metal stents are superior to double-pigtail stents, prospective multicenter studies focusing on safety as well as long-term follow-up are first needed.

Management of Inflammatory Fluid Collections and Walled-Off Pancreatic Necrosis

OPINION STATEMENT

Pancreatic fluid collections are a frequent complication of acute pancreatitis. The revised Atlanta criterion classifies chronic fluid collections into pseudocysts and walled-off pancreatic necrosis (WON). Symptomatic PFCs require drainage options that include surgical, percutaneous, or endoscopic approaches. With the advent of newer and more advanced endoscopic tools and expertise, minimally invasive endoscopic drainage has now become the preferred approach. An endoscopic ultrasonography (EUS)-guided approach for pancreatic fluid collection drainage is now the preferred endoscopic approach. Both plastic stents and metal stents are efficacious and safe; however, metal stents may offer an advantage, especially in infected pseudocysts and in WON. Direct endoscopic necrosectomy is often required in WON. Lumen apposing metal stents allow for direct endoscopic necrosectomy and debridement through the stent lumen and are now preferred in these patients. Endoscopic retrograde cholangiopancreatography with pancreatic duct exploration should be performed concurrent to PFC drainage in patients with suspected PD disruption. PD disruption is associated with an increased severity of pancreatitis, an increased risk of recurrent attacks of pancreatitis and long-term complications, and a decreased rate of PFC resolution after drainage. Ideally, pancreatic ductal disruption should be bridged with endoscopic stenting.

集束化护理在重症急性胰腺患者胃肠功能恢复中的应用

重症急性胰腺炎(severe acute pancreatitis, SAP)是临床中常见的发病率高、并发症多、死亡率较高的疾病, 其死亡的主要原因是并发了不同程度的多器官功能障碍综合征(multiple organ dysfunction syndrome, MODS), 全身炎症反应综合征(systemic inflammatory response syndrome, SIRS)是导致MODS的重要基础, 而胃肠功能障碍又是激发SIRS的源头. 因此, 胃肠功能障碍在该病的发生发展过程中起重要作用, 早期胃肠功能恢复有助于疾病的恢复和并发症的预防. 集束化护理的运用, 可以使每一位患者在有限的时间内, 得到最有效的治疗, 这是集束化护理最突出的特点. 文章就集束化护理在SAP患者的胃肠功能恢复中的应用进行简要综述, 为临床工作提供循证参考.

Clinical impact of EUS treatment of walled-off pancreatic necrosis with dedicated devices

BACKGROUND AND STUDY AIMS

 Walled-off pancreatic necrosis (WOPN) represents the major risk factor for sepsis-related multiple organ failure. Surgical debridement is an invasive approach associated with high rates of adverse events (AEs) and death. As an alternative, endoscopic ultrasound-guided cysto-gastro-anastomosis has emerged as an effective treatment for WOPNs. Recently a new dedicated-lumen apposing metal stent (LAMS) has been used with satisfactory results in treating peri-pancreatic fluid collections, including WOPNs. The primary outcomes of this study were to evaluate survival and clinical success. Secondary outcomes included: technical success, adverse events and recurrence rate.

PATIENTS AND METHODS

 All consecutive patients with infected WOPN between February 2014 and June 2016 were retrospectively reviewed. Patients underwent placement of a new LAMS incorporated in an electrocautery-enhanced delivery system and direct endoscopic necrosectomy (DEN). DEN was performed immediately after stent deployment and repeated every 3 to 7 days until complete resolution.

RESULTS

 In the study period we treated 20 consecutive patients with infected WOPN using the new LAMS. Technical success was achieved in 95 % of patients. Clinical success was achieved in 73 % and 84.2 % of patients at 1 and 3 months, respectively. Survival rate was 84.2 % and 79 %. Mean length of hospital stay was 19 days (range 3 - 43). No AEs occurred. Patients were followed up after stent retrieval for a mean time of 554,7 days (range 70 - 986) and no recurrence was observed.

CONCLUSIONS

 DEN following "1-step, exchange-free" LAMS positioning recorded excellent results. We believe that simplicity of procedure plays a key role in terms of safety.

Necrotizing Pancreatitis: Current Management and Therapies

Acute necrotizing pancreatitis accounts for 10% of acute pancreatitis (AP) cases and is associated with a higher mortality and morbidity. Necrosis within the first 4 weeks of disease onset is defined as an acute necrotic collection (ANC), while walled off pancreatic necrosis (WOPN) develops after 4 weeks of disease onset. An infected or symptomatic WOPN requires drainage. The management of pancreatic necrosis has shifted away from open necrosectomy, as it is associated with a high morbidity, to less invasive techniques. In this review, we summarize the current management and therapies for acute necrotizing pancreatitis.

Endoscopic Management of Pancreatic Fluid Collections

Pancreatic fluid collections (PFCs) may develop due to inflammation secondary to acute and/or chronic pancreatitis, trauma, surgery, or obstruction from solid or cystic neoplasms. PFCs can be drained percutaneously, surgically, or endoscopically with endoscopic ultrasound-guided cyst gastrostomy and/or transpapillary drainage through endoscopic retrograde cholangiopancreatography. There has been a paradigm shift in the endoscopic management of PFCs in the past few years with newer techniques including utilization of self-expanding metal stents and multiport devices. This review is a comprehensive update on the classification of PFC, indications for drainage, optimal approach, and techniques.

Asian consensus statements on endoscopic management of walled-off necrosis. Part 2: Endoscopic management

Walled-off necrosis (WON) is a new term for encapsulated necrotic tissue after severe acute pancreatitis. Various terminologies such as pseudocyst, necroma, pancreatic abscess, and infected necrosis were previously used in the literature, resulting in confusion. The current and past terminologies must be reconciled to meaningfully interpret past data. Recently, endoscopic necrosectomy was introduced as a treatment option and is now preferred over surgical necrosectomy when the expertise is available. However, high-quality evidence is still lacking, and there is no standard management strategy for WON. The consensus meeting aimed to clarify the diagnostic criteria for WON and the role of endoscopic interventions in its management. In the Consensus Conference, 27 experts from eight Asian countries took an active role and examined key clinical aspects of WON diagnosis and endoscopic management. Statements were crafted based on literature review and expert opinion, employing the modified Delphi method. All statements were substantiated by the level of evidence and the strength of the recommendation. We created 27 consensus statements for WON diagnosis and management, including details of endoscopic procedures. When there was not enough solid evidence to support the statements, this was clearly acknowledged to facilitate future research. Proposed management strategies were formulated and are illustrated using flow charts. These recommendations, which are based on the best current scientific evidence and expert opinion, will be useful for guiding endoscopic management of WON. Part 2 of this statement focused on the endoscopic management of WON.

Minimally Invasive Necrosectomy Techniques in Severe Acute Pancreatitis: Role of Percutaneous Necrosectomy and Video-Assisted Retroperitoneal Debridement

Consensus advocating a principle of early organ support, nutritional optimisation, followed ideally by delayed minimally invasive intervention within a “step-up” framework where possible has radically changed the surgical approach to complications of acute pancreatitis in the last 20 years. The 2012 revision of the Atlanta Classification incorporates these changes, and provides a background which underpins the complexities of individual patient management decisions. This paper discusses the place for delayed minimally invasive surgical intervention (percutaneous necrosectomy, video-assisted retroperitoneal debridement (VARD)), and the rationale for opting to adopt a percutaneous approach over endoscopic or laparoscopic approaches in different clinical situations.

Cyst Gastrostomy and Necrosectomy for the Management of Sterile Walled-Off Pancreatic Necrosis: a Comparison of Minimally Invasive Surgical and Endoscopic Outcomes at a High-Volume Pancreatic Center

INTRODUCTION

Walled-off pancreatic necrosis (WON) is a sequela of acute necrotizing pancreatitis in 15-40% of cases. We sought to compare the outcomes of minimally invasive surgical and endoscopic cyst gastrostomy (CG) and necrosectomy for the management for sterile WON at a tertiary care high-volume pancreas center.

METHOD

This is a retrospective review of patients who underwent minimally invasive surgical or endoscopic CG and necrosectomy for clinically sterile WON between 2008 and 2013. Peri-procedural outcomes including costs were analyzed and compared.

RESULTS

Twenty patients underwent minimally invasive surgical (robotic = 14, laparoscopic = 6) CG and necrosectomy, and 20 patients underwent endoscopic treatment. The surgical cohort had a larger median cyst size and higher CCI score. For the surgical cohort, median OR time was 167.5 min, estimated blood loss was 30 ml, and 65% underwent concomitant cholecystectomy. There was no mortality in either group and no difference in complication rates (20%). The failure rate was similar (15 versus 10%, P = 0.66). Although surgery was associated with a lower re-intervention rate (0 versus 1, P = 0.008), the endotherapy group was associated with shorter total LOS (inclusive of re-interventions) (7 versus 3 days, P = 0.032). The cost of the index procedure was significantly higher for the surgery group (P = 0.014); however, when considering all readmissions and re-interventions until resolution of the WON, the total cost was similar for both groups.

CONCLUSION

Minimally invasive surgical and endoscopic CG and necrosectomy are comparable treatments for sterile WON in terms of outcomes and overall cost. The surgical approach may be considered advantageous when a concomitant cholecystectomy is required.

Endoscopic ultrasound guided interventional procedures

Endoscopic ultrasound (EUS) has emerged as an important diagnostic and therapeutic modality in the field of gastrointestinal endoscopy. EUS provides access to many organs and lesions which are in proximity to the gastrointestinal tract and thus giving an opportunity to target them for therapeutic and diagnostic purposes. This modality also provides a real time opportunity to target the required area while avoiding adjacent vascular and other structures. Therapeutic EUS has found role in management of pancreatic fluid collections, biliary and pancreatic duct drainage in cases of failed endoscopic retrograde cholangiopancreatography, drainage of gallbladder, celiac plexus neurolysis/blockage, drainage of mediastinal and intra-abdominal abscesses and collections and in targeted cancer chemotherapy and radiotherapy. Infact, therapeutic EUS has emerged as the therapy of choice for management of pancreatic pseudocysts and recent innovations like fully covered removable metallic stents have improved results in patients with organised necrosis. Similarly, EUS guided drainage of biliary tract and pancreatic duct helps drainage of these systems in patients with failed cannulation, inaccessible papilla as with duodenal/gastric obstruction or surgically altered anatomy. EUS guided gall bladder drainage is a useful emergent procedure in patients with acute cholecystitis who are not fit for surgery. EUS guided celiac plexus neurolysis and blockage is more effective and less morbid vis-à-vis the percutaneous technique. The field of interventional EUS is rapidly advancing and many more interventions are being continuously added. This review focuses on the current status of evidence vis-à-vis the established indications of therapeutic EUS.

Endoscopic extra-cavitary drainage of pancreatic necrosis with fully covered self-expanding metal stents (fcSEMS) and staged lavage with a high-flow water jet system

AIM

To present a novel, less-invasive method of endoscopic drainage (ED) for walled-off pancreatic necrosis (WON).We describe the feasibility, success rate, and complications of combined ED extra-cavitary lavage and debridement of WON using a biliary catheter and high-flow water jet system (water pump).

PATIENTS AND METHODS

Endoscopic ultrasound (EUS)-guided drainage was performed with insertion of two 7-Fr, 4-cm double pigtail stents. Subsequently a fully covered self-expanding metal stent (fcSEMS) was placed. The key aspect of the debridement was the insertion of a 5-Fr biliary catheter through or along the fcSEMS into the cavity, with ensuing saline lavage using a high-flow water jet system. The patients were then brought back for repeated, planned endoscopic lavages of the WON. No endoscopic intra-cavitary exploration was performed.

RESULTS

A total of 17 patients (15 men, 2 women; mean age 52.6, range 24 - 69; mean American Society of Anesthesiologists [ASA] score of 3) underwent ED of WON with this new method. The mean initial WON diameter was 9.5 cm, range 8 to 26 cm. The total number of ED was 84, range 2 to 13. The mean stenting period was 42.5 days. The mean follow-up was 51 days, range 3 to 370. A resolution of the WON was achieved in 14 patients (82.3 %). There were no major complications associated with this method.

CONCLUSION

ED of complex WON with fcSEMS followed by repeated endoscopic extra-cavitary lavage and debridement using a biliary catheter and high-flow water jet system is a minimally invasive, feasible method with high technical and clinical success and minimal complications.