Delayed endoscopic necrosectomy improves hospital length of stay and reduces endoscopic interventions in patients with symptomatic walled‐off necrosis

Controversies in endoscopic ultrasonography-guided management of walled-off necrosis

Walled-off necrosis (WON) develops as local complications after acute necrotizing pancreatitis. Although less invasive interventions such as endoscopic ultrasonography (EUS)-guided drainage and endoscopic necrosectomy are selected over surgical interventions, delayed and step-up interventions are still preferred to avoid procedure-related adverse events. However, there is a controversy about the appropriate timing of drainage and subsequent necrosectomy. The advent of large-caliber lumen-apposing metal stents has also brought about potential advantages of proactive interventions, which still needs investigation in future trials. When step-up interventions of necrosectomy and additional drainage are necessary, a structured or protocoled approach for WON has been reported to improve safety and effectiveness of endoscopic and/or percutaneous treatment, but has not been standardized yet. Finally, long-term outcomes such as recurrence of WON, pancreatic endocrine, and exocrine function are increasingly investigated in association with disconnected pancreatic duct syndrome. In this review we discuss current evidence and controversy on EUS-guided management of WON.

Infected pancreatic necrosis-Current trends in management

Acute necrotizing pancreatitis is a common gastrointestinal disease requiring hospitalization and multiple interventions resulting in higher morbidity and mortality. Development of infection in such necrotic tissue is one of the sentinel events in natural history of necrotizing pancreatitis. Infected necrosis develops in around 1/3rd of patients with necrotizing pancreatitis resulting in higher mortality. So, timely diagnosis of infected necrosis using clinical, laboratory and radiological parameters is of utmost importance. Though initial conservative management with antibiotics and organ support system is effective in some patients, a majority of patients still requires drainage of the collection by various modalities. Mode of drainage of infected pancreatic necrosis depends on various factors such as the clinical status of the patient, location and characteristics of collection and availability of the expertise and includes endoscopic, percutaneous and minimally invasive or open surgical approaches. Endoscopic drainage has proved to be a game changer in the management of infected pancreatic necrosis in the last decade with rapid evolution in procedure techniques, development of novel metal stent and dedicated necrosectomy devices for better clinical outcome. Despite widespread adoption of endoscopic transluminal drainage of pancreatic necrosis with excellent clinical outcomes, peripheral collections are still not amenable for endoscopic drainage and in such scenario, the role of percutaneous catheter drainage or minimally invasive surgical necrosectomy cannot be understated. In a nutshell, the management of patients with infected pancreatic necrosis involves a multi-disciplinary team including a gastroenterologist, an intensivist, an interventional radiologist and a surgeon for optimum clinical outcomes.

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.

Indications, Techniques and Future Perspectives of Walled-off Necrosis Management

Necrotizing pancreatitis is a complex clinical condition burdened with significant morbidity and mortality. In recent years, the huge progress of interventional endoscopic ultrasound (EUS) has allowed a shift in the management of pancreatic necrotic collections from surgical/percutaneous approaches to mini-invasive endoscopic internal drainage and debridement procedures. The development of lumen-apposing metal stents (LAMSs), devices specifically dedicated to transmural EUS interventions, further prompted the diffusion of such techniques. Several studies have reported excellent outcomes of endoscopic interventions, in terms of technical success, clinical efficacy and safety compared to surgical interventions, and thus endoscopic drainage of walled-off necrosis (WON) has become a fundamental tool for the management of such conditions. Despite these advancements, some critical unresolved issues remain. Endoscopic therapeutic approaches to WON are still heterogeneous among different centers and experts. A standardized protocol on indication, timing and technique of endoscopic necrosectomy is still lacking, and experts often adopt a strategy based on personal experience more than robust data from well-conducted studies. In this review, we will summarize the available evidence on endoscopic management of WON and will discuss some unanswered questions in this rapidly evolving field.

Endoscopic management of pancreatic collections. Endoscopic Ultrasound Group from the Spanish Society of Digestive Endoscopy (GSEED-USE) Clinical Guidelines

Acute pancreatitis is associated with significant morbidity and mortality. It can develop complications such as fluid collections and necrosis. Infection of necrosis occurs in about 20-40% of patients with severe acute pancreatitis, and is associated with organ failure and worse prognosis. In the past years, the treatment of pancreatic collections has shifted from open surgery to minimally invasive techniques, such as endoscopic ultrasound guided drainage. These guidelines from a selection of experts among the Endoscopic Ultrasound Group from the Spanish Society of Gastrointestinal Endoscopy (GSEED-USE) have the purpose to provide advice on the management of pancreatic collections based on a thorough review of the available scientific evidence. It also reflects the experience and clinical practice of the authors, who are advanced endoscopists or clinical pancreatologists with extensive experience in managing patients with acute pancreatitis.

Upfront endoscopic necrosectomy or step-up endoscopic approach for infected necrotising pancreatitis (DESTIN): a single-blinded, multicentre, randomised trial

BACKGROUND

Although the preferred management approach for patients with infected necrotising pancreatitis is endoscopic transluminal stenting followed by endoscopic necrosectomy as step-up treatment if there is no clinical improvement, the optimal timing of necrosectomy is unclear. Therefore, we aimed to compare outcomes between performing upfront necrosectomy at the index intervention versus as a step-up measure in patients with infected necrotising pancreatitis.

METHODS

This single-blinded, multicentre, randomised trial (DESTIN) was done at six tertiary care hospitals (five hospitals in the USA and one hospital in India). We enrolled patients (aged ≥18 years) with confirmed or suspected infected necrotising pancreatitis with a necrosis extent of at least 33% who were amenable to endoscopic ultrasound-guided drainage. By use of computer-generated permuted block randomisation (block size four), eligible patients were randomly assigned (1:1) to receive either upfront endoscopic necrosectomy or endoscopic step-up treatment. Endoscopists were not masked to treatment allocation, but participants, research coordinators, and the statistician were. Lumen-apposing metal stents (20 mm diameter; 10 mm saddle length) were used for drainage in both groups. In the upfront group, direct necrosectomy was performed immediately after stenting in the same treatment session. In the step-up group, direct necrosectomy or additional drainage was done at a subsequent treatment session if there was no clinical improvement (resolution of any criteria of systemic inflammatory response syndrome or sepsis or one or more organ failure and at least a 25% percentage decrease in necrotic collection size) 72 h after stenting. The primary outcome was the number of reinterventions per patient to achieve treatment success from index intervention to 6 months' follow-up, which was defined as symptom relief in conjunction with disease resolution on CT. Reinterventions included any endoscopic or radiological procedures performed for necrosectomy or additional drainage after the index intervention, excluding the follow-up procedure at 4 weeks for stent removal. All endpoints and safety were analysed by intention-to-treat. This study is registered with ClinicalTrials.gov, NCT05043415 and NCT04113499, and recruitment and follow-up have been completed.

FINDINGS

Between Nov 27, 2019, and Oct 26, 2022, 183 patients were assessed for eligibility and 70 patients (24 [34%] women and 46 [66%] men) were randomly assigned to receive upfront necrosectomy (n=37) or step-up treatment (n=33) and included in the intention-to-treat population. At the time of index intervention, seven (10%) of 70 patients had organ failure and 64 (91%) patients had walled-off necrosis. The median number of reinterventions was significantly lower for upfront necrosectomy (1 [IQR 0 to 1] than for the step-up approach (2 [1 to 4], difference -1 [95% CI -2 to 0]; p=0·0027). Mortality did not differ between groups (zero patients in the upfront necrosectomy group vs two [6%] in the step-up group, difference -6·1 percentage points [95% CI -16·5 to 4·5]; p=0·22), nor did overall disease-related adverse events (12 [32%] patients in the upfront necrosectomy group vs 16 [48%] patients in the step-up group, difference -16·1 percentage points [-37·4 to 7·0]; p=0·17), nor procedure-related adverse events (four [11%] patients in the upfront necrosectomy group vs eight [24%] patients in the step-up group, difference -13·4 percentage points [-30·8 to 5·0]; p=0·14).

INTERPRETATION

In stabilised patients with infected necrotising pancreatitis and fully encapsulated collections, an approach incorporating upfront necrosectomy at the index intervention rather than as a step-up measure could safely reduce the number of reinterventions required to achieve treatment success.

FUNDING

None.

Time to think prime times for treatment of necrotizing pancreatitis: Pendulum conundrum

Pancreatic fluid collections (PFCs) typically develop as local complications of acute pancreatitis and complicate the clinical course of patients with acute pancreatitis and potentially fatal clinical outcomes. Interventions are required in cases of symptomatic walled-off necrosis (WON) (matured PFCs with necrosis) and pancreatic pseudocysts (matured PFCs without necrosis). In the management of necrotizing pancreatitis and WON, endoscopic ultrasound-guided transluminal drainage combined with on-demand endoscopic necrosectomy (i.e. the step-up approach) is increasingly used as a less invasive treatment modality compared with a surgical or percutaneous approach. Through the substantial research efforts and development of specific devices and stents (e.g. lumen-apposing metal stents), endoscopic techniques of PFC management have been standardized to some extent. However, there has been no consensus about timing of carrying out each treatment step; for instance, it is uncertain when direct endoscopic necrosectomy should be initiated and finished and when a plastic or metal stent should be removed following clinical treatment success. Despite emerging evidence for the effectiveness of noninterventional supportive treatment (e.g. antibiotics, nutritional support, irrigation of the cavity), there has been only limited data on the timing of starting and stopping the treatment. Large studies are required to optimize the timing of those treatment options and improve clinical outcomes of patients with PFCs. In this review, we summarize the current available evidence on the indications and timing of interventional and supportive treatment modalities for this patient population and discussed clinical unmet needs that should be addressed in future research.

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.