What are the guidelines for managing necrotizing pancreatitis, including investigations and treatment?

Management of Necrotizing Pancreatitis

Initial Management and Monitoring

All patients with necrotizing pancreatitis must be managed in a high dependency unit (HDU) or intensive care unit (ICU) with comprehensive monitoring and full systems support. 1, 2

• Implement hourly assessment of vital signs including pulse, blood pressure, central venous pressure (CVP), respiratory rate, oxygen saturation, urine output, and temperature 1, 2
• Provide oxygen supplementation to maintain arterial saturation >95% 2
• Monitor laboratory markers including hematocrit, blood urea nitrogen, creatinine, and lactate as indicators of tissue perfusion 1
• Perform severity stratification within 48 hours of diagnosis using APACHE II score, CRP >150 mg/L, Glasgow score ≥3, or persistent organ failure 3

Investigations

Initial Diagnostic Imaging

• Obtain dynamic contrast-enhanced CT scanning within 3-10 days of admission using non-ionic contrast to assess the extent of necrosis 1, 2
• Perform ultrasound examination of the gallbladder within 24 hours of diagnosis to evaluate for biliary etiology 4

Follow-up Imaging

• Obtain CT imaging in patients with persisting organ failure, signs of sepsis, or clinical deterioration 6-10 days after admission 4
• Perform follow-up CT scans only if the patient's clinical status deteriorates or fails to show continued improvement 2

Assessment for Infected Necrosis

• Perform image-guided fine needle aspiration in all patients with persistent symptoms and >30% pancreatic necrosis, or those with smaller areas of necrosis and clinical suspicion of sepsis 4, 1, 2
• CT-guided fine needle aspiration for Gram stain and cultures is unnecessary in the majority of cases when infection is clinically evident (gas in collection, bacteremia, sepsis) 5

Fluid Resuscitation

• Administer crystalloid or colloid to maintain urine output >0.5 mL/kg body weight 2
• Use goal-directed therapy with non-aggressive resuscitation at 1.5 mL/kg/hr following an initial bolus of 10 mL/kg 3
• Avoid hydroxyethyl starch fluids as they may increase risk of multiple organ failure 3

Nutritional Support

Initiate early enteral nutrition within 24 hours via nasogastric or nasojejunal tube to prevent gut failure and infectious complications. 1, 2

• Begin oral food intake immediately in patients without nausea, vomiting, or signs of severe ileus 1, 5
• Use nasogastric feeding as the initial route, which is effective in approximately 80% of cases 3
• Reserve nasojejunal feeding for patients who cannot tolerate nasogastric feeding 1
• Use total parenteral nutrition only when enteral nutrition is not feasible or tolerated 1, 5

Antibiotic Management

Do not administer prophylactic antibiotics routinely for prevention of pancreatic necrosis infection. 1, 5

• Administer antibiotics only when specific infections are documented (infected necrosis, respiratory infections, urinary infections) 1, 5
• When infected necrosis is suspected, use broad-spectrum intravenous antibiotics with ability to penetrate pancreatic necrosis (carbapenems, quinolones, metronidazole) 5
• If antibiotic prophylaxis is used, limit duration to a maximum of 14 days in the absence of positive cultures 4, 3
• Do not routinely use antifungal agents 5

Pain Management

• Implement a multimodal approach to pain management 1
• Consider epidural analgesia for patients requiring high doses of opioids for extended periods 1
• Avoid NSAIDs in patients with acute kidney injury 1

Management Based on Necrosis Type

Sterile Necrosis (Mortality 0-11%)

• Focus on fluid resuscitation, nutritional support, and monitoring for complications 1, 2
• Surgery is indicated only when there is no clinical improvement despite maximal ICU treatment after 4 weeks 6
• Only 4% of patients with sterile necrosis require surgical intervention 6

Infected Necrosis (Mortality 24-30%)

Delay interventions for infected necrosis until at least 4 weeks after disease onset when possible, as this results in lower mortality. 1, 2

• 95% of patients with infected necrosis will require intervention 6
• Implement a step-up approach: start with percutaneous or endoscopic drainage, then progress to minimally invasive necrosectomy if no improvement occurs 1, 5
• Complete debridement of all cavities containing necrotic material is required 4

Indications for Early Intervention (<4 weeks)

• Abdominal compartment syndrome unresponsive to conservative management 1, 2
• Acute ongoing bleeding when endovascular approach is unsuccessful 1, 2
• Bowel ischemia or acute necrotizing cholecystitis 1, 2

Management of Biliary Pancreatitis

Perform urgent therapeutic ERCP within 72 hours in patients with acute pancreatitis of suspected or proven gallstone etiology who have cholangitis, jaundice, or a dilated common bile duct. 1, 2, 3

• All patients with biliary pancreatitis must undergo definitive management of gallstones during the same hospital admission, unless a clear plan for definitive treatment within the next two weeks has been made 4, 1, 2, 3

Referral Criteria

Transfer patients with extensive necrotizing pancreatitis to a specialist unit with expertise in interventional radiology, endoscopy, pancreatic surgery, and ICU care. 4, 1, 2

• Specialist units must have 24-hour access to contrast-enhanced helical or multislice CT or MRI, percutaneous image-guided aspiration and drainage techniques, and angiography 4
• Every hospital receiving acute admissions should have a single nominated clinical team to manage all patients with acute pancreatitis 4, 1

Expected Outcomes

• Target overall mortality <30% in severe disease 1
• Mortality for sterile necrosis: 0-11% 1
• Mortality for infected necrosis: 24-30% 1, 6
• Approximately one-third of deaths occur in the early phase from multiple organ failure, while most deaths after the first week are due to infected necrosis 1

Critical Pitfalls to Avoid

• Do not delay diagnosis beyond 48 hours of admission 3
• Avoid aggressive fluid resuscitation protocols that may lead to fluid overload and increased mortality 1, 3
• Do not perform early surgical intervention (<4 weeks) for pancreatic necrosis, which results in higher mortality 3, 5
• Do not routinely administer prophylactic antibiotics 1, 5