What is the management of walled-off pancreatic necrosis (WOPN)?

From the Guidelines

The management of walled-off pancreatic necrosis should start with a step-up approach, using percutaneous drainage as the first line of treatment, which can delay surgical intervention to a more favorable time or even result in complete resolution of infection in 25-60% of patients. This approach is supported by the 2019 WSES guidelines for the management of severe acute pancreatitis 1. The guidelines recommend percutaneous drainage as the first line of treatment for infected pancreatic necrosis, with a step-up approach to more invasive interventions if needed.

Key Considerations

• Minimally invasive surgical strategies, such as transgastric endoscopic necrosectomy or video-assisted retroperitoneal debridement (VARD), can result in less postoperative new-onset organ failure, but may require more interventions 1.
• There is insufficient evidence to support one surgical approach over another in terms of mortality, highlighting the need for individualized treatment plans 1.
• A multidisciplinary group of experts should be involved in the decision-making process, taking into account local expertise and the specific needs of each patient 1.

Treatment Options

• Percutaneous drainage: can be used as a first-line treatment for infected pancreatic necrosis, with the potential to delay or avoid surgical intervention 1.
• Endoscopic drainage: can be used for collections adjacent to the stomach or duodenum, with endoscopic ultrasound-guided transmural drainage and direct endoscopic necrosectomy being effective options 1.
• Video-assisted retroperitoneal debridement (VARD) and minimally invasive surgical necrosectomy: can be used for cases where less invasive approaches fail 1.
• Open surgical necrosectomy: is now rarely performed due to its high morbidity and mortality rates, and should only be considered in exceptional cases 1.

From the Research

Management of Walled Off Pancreatic Necrosis

• The management of walled off pancreatic necrosis (WON) involves a multidisciplinary approach, including gastroenterologists, surgeons, interventional radiologists, and specialists in critical care medicine, infectious disease, and nutrition 2.
• Antimicrobial therapy is best indicated for culture-proven infection in pancreatic necrosis or when infection is strongly suspected, and broad-spectrum intravenous antibiotics with ability to penetrate pancreatic necrosis should be favored 2.
• Enteral feeding should be initiated early to decrease the risk of infected necrosis, and a trial of oral nutrition is recommended immediately in patients in whom there is absence of nausea and vomiting and no signs of severe ileus or gastrointestinal luminal obstruction 2.
• Drainage and/or debridement of pancreatic necrosis is indicated in patients with infected necrosis, and may be required in patients with sterile pancreatic necrosis and persistent unwellness or with associated complications 2.

Endoscopic Management

• Endoscopic transmural drainage has been recognized as the first-line treatment for pancreatic fluid collections, and offers a minimally invasive approach when compared to surgical drainage 3.
• Self-expanding metal stents, pigtail stents, or lumen-apposing metal stents can be used to facilitate drainage of fluid collections, and current data suggest that all 3 approaches yield similar outcomes 3.
• The use of direct endoscopic necrosectomy should be reserved for those patients with limited necrosis who do not adequately respond to endoscopic transmural drainage using large-bore, self-expanding metal stents/lumen-apposing metal stents alone or plastic stents combined with irrigation 2.
• Endoscopic step-up approach, which consists of EUS-guided transluminal drainage followed by, if necessary, endoscopic necrosectomy, has been proposed as a treatment algorithm for necrotizing pancreatitis, and may be more advantageous than a minimally invasive surgical step-up approach 4.

Step-Up Approach

• A step-up approach consisting of percutaneous drainage or endoscopic transmural drainage using either plastic stents and irrigation or self-expanding metal stents/lumen-apposing metal stents alone, followed by direct endoscopic necrosectomy, and then surgical debridement is reasonable, although approaches may vary based on the available clinical expertise 2.
• The step-up approach has been shown to result in favorable outcomes with small numbers proceeding to open surgery, and with acceptable rates of major complications and mortality 5.
• The algorithm based step-up approach for interventions in necrotizing pancreatitis using primarily endoscopic techniques with adjunctive percutaneous approaches as needed has been shown to be effective in managing WON 5.