What considerations are necessary when planning cystogastrostomy and LAMS (Lumen-Apposing Metal Stent) for pancreatic wall necrosis?

Key Considerations for Cystogastrostomy and LAMS for Pancreatic Wall of Necrosis

Multidisciplinary involvement is essential when planning cystogastrostomy and LAMS placement for pancreatic wall of necrosis, as this procedure requires coordination between endoscopists, interventional radiologists, surgeons, and critical care specialists to optimize outcomes and manage potential complications. 1

Pre-Procedure Assessment

• Imaging evaluation: CT scan with non-ionic contrast should be obtained within 3-10 days of admission to:

  • Assess extent of pancreatic necrosis
  • Identify peripancreatic fluid collections
  • Detect gas in retroperitoneal area (suggesting infection) 2
  • Evaluate for intervening vessels that may complicate drainage 1

• Collection characteristics: Determine if the collection is:

  • Walled-off pancreatic necrosis (WOPN)
  • Pseudocyst
  • Mixed collection
  • Assess for presence of solid debris vs liquid component 1

• Timing considerations:

  • Debridement should be delayed for at least 4 weeks when possible to allow for adequate walling-off of the collection 3
  • Early intervention (<2 weeks) is associated with increased morbidity and mortality 3

Procedural Considerations

Stent Selection

• LAMS advantages:

  • Larger diameter allows better drainage of necrotic material
  • Bi-flanged design provides anti-migratory properties
  • Enables direct endoscopic necrosectomy through the stent 1
  • Creates sustained cystogastrostomy tract for drainage and treatment 4

• LAMS considerations:

  • Higher lumen-apposing force may reduce leakage but can potentially cause adverse events 1
  • Serious adverse events including delayed bleeding, buried stent syndrome, and biliary stricture have been reported in up to 50% of patients in one study 1
  • More expensive than plastic stents 1

• Plastic stent alternative:

  • One or two plastic double pigtail stents have traditionally been used with technical and clinical success rates over 90% 1
  • More cost-effective than LAMS 1

Technical Aspects

• Fluoroscopy guidance is essential for:

  • Monitoring guidewire position during looping within the collection
  • Ensuring proper stent placement 1

• Antibiotic prophylaxis:

  • Prophylactic antibiotics are recommended before the procedure
  • Antibiotics should be continued post-procedurally 1
  • For confirmed infection, use antibiotics with good pancreatic tissue penetration (e.g., carbapenems) 2, 3

Post-Procedure Management

• Direct endoscopic necrosectomy (DEN):

  • May be required for collections with significant solid debris
  • Can be performed immediately after stent deployment and repeated every 3-7 days until complete resolution 5
  • Should be reserved for patients who don't respond adequately to drainage alone 3

• Step-up approach:

  • Begin with endoscopic transmural drainage using LAMS
  • Progress to direct endoscopic necrosectomy if needed
  • Consider surgical debridement only if endoscopic approaches fail 3

• Nutritional support:

  • Enteral nutrition should be initiated early to decrease risk of infected necrosis 3
  • Oral nutrition can be attempted if there's no nausea, vomiting, or ileus 3

Potential Complications

• Bleeding: Can occur during or after the procedure, especially with LAMS 1, 4
• Infection: Converting a clean system to a clean-contaminated environment 1
• Stent migration: Reported in approximately 5.6% of patients with LAMS 4
• Buried stent syndrome: The flange of the stent can become embedded in the gastric or collection wall 1
• Biliary stricture: Reported as a potential complication with LAMS 1

Follow-up and Stent Removal

• Monitoring: Regular follow-up imaging to assess collection resolution
• Stent removal: Once the collection has resolved, typically after 4-8 weeks
• Disconnected pancreatic duct: Evaluate for disconnected pancreatic duct, which may require additional intervention 3

Institutional Requirements

• Multidisciplinary team: Centers performing the procedure should have support from interventional radiologists, surgeons, and anesthesiologists 1
• Expertise: Procedures should be performed at centers with adequate endoscopic expertise and surgical backup 3
• Equipment: Availability of appropriate endoscopic equipment, fluoroscopy, and stents is essential

By carefully considering these factors and following a systematic approach, cystogastrostomy with LAMS placement can be an effective minimally invasive treatment for pancreatic wall of necrosis with high technical and clinical success rates.