Acute Pancreatitis

Acute Pancreatitis – Alex Wiles

Background

  • Common causes: Gallstones (40%), EtOH (30%), smoking
  • Other causes: post-ERCP, pancreatic cancer/obstruction, blunt abdominal trauma, hypertriglyceridemia (TG >1000), hypercalcemia, drugs (thiazides, protease inhibitors, azathioprine, 6MP), mumps, Coxsackie, vasculitis, pregnancy, genetic (PRSS1, SPINK1, CFTR), autoimmune (IgG4), scorpion venom
  • Most important intervention during the first 12 – 24 hr and has direct effect on mortality
    • SIRS leads to 3rd spacing and dehydration
  • Several scoring systems:
  • BISAP (BUN >25, Impaired mental status, SIRS, Age>60, Pleural effusion)
    • 0 – 2   Mortality < 2%; 3 - 5 Mortality > 15 %
  • APACHE II (MD Calc, several factors)
    • Decreasing values = mild attack; increasing values = severe attack
    • 0 – 8 Mortality <4%;  > 8   Mortality 11 – 18 %
  • Ranson’s Criteria (MD Calc, severity at 0 and 48 hours)
    • < 3   Mortality 0 – 3 %; > 3 Mortality 11 – 15 %;  > 6 Mortality 40 %

 

Presentation

  • Atlanta criteria requires two of three (PIE)
    • Pain characteristic of pancreatitis (sharp, epigastric, radiating to back)
    • Imaging characteristic of pancreatitis (US, CT, MRI)
    • Enzymes (lipase or amylase) >3x ULN (use lipase, much more specific)
    • *If pain is characteristic and lipase > 3xULN, no need for CT A/P
  • Grading Severity:
    • Mild: no organ failure or systemic complications
    • Moderate: transient organ failure (<48 hours)
    • Severe: persistent organ failure (>48 hours)

 

Evaluation

  • Lipase, CBC, CMP, lipid panel, lactate, direct bilirubin
  • Obtain RUQ U/S for all pts, evaluates for gallstones 
  • CT A/P w/  IV contrast
    • Reserved for patients not improving at 48-72 hour to assess for complications
    • If performed at onset, underestimates severity (necrosis takes 72 hours from onset)

 

Management

  • Fluids, Fluids, Fluids:
  • First 12-24 hrs: LR at 200 to 500 cc/hr, or 5-10 cc/kg / hr (2.5 – 4 L within first 24 hrs)
  • Follow HCT and BUN as markers for successful fluid resuscitation
    • Aggressive IVF in first 24 hours reduces both morbidity and mortality
    • Persistent hemoconcentration at 24 hr associated w/ necrotizing pancreatitis
  • Pain Control:
    • Common starting narcotic regimen is oxycodone 10 mg q6H PRN and hydromorphone 0.5 mg q3h - q4h for breakthrough (can refer to inpatient pain control section)
    • Consider consult to acute pain service for assistance

 

  • Nutrition:
    • NPO but start PO diet as soon as patient can tolerate (even within 24 hours)
    • Clear liquid diet or mechanical soft and advance as tolerated
    • Low fat diet (Fatty acids  CCK → trypsinogen to trypsin)
    • If NPO > 72 hours, attempt PO and if fail, place Dobhoff for enteral nutrition at latest by day five… outcomes with NG/NJ >>> TPN

 

  • Antibiotics:
    • Fever, leukocytosis common, not an indication for ABX as the necrosis is sterile
    • Infection of the necrosis should be suspected w/ failure to improve 7 days after onset
      • Cefepime + Flagyl or carbapenem
    • EUS or IR guided drain for aspirate: only done if fluid is walled-off—at least 4 weeks
    • Infected pseudocysts or walled-off pancreatic necrosis may require prolonged course of ABX and serial imaging 

 

Additional Information

  • If choledocholithiasis suspected ERCP
  • If the diagnosis is in question MRCP  
  • If biliary sludge but no stones on U/S, still consider cholecystectomy (likely microlithiasis)
  • Complications:
    • ARDS, abdominal compartment syndrome, AKI, DIC
    • < 4 weeks after pancreatitis: Peripancreatic fluid collection, acute necrotic collection
    • > 6 weeks after pancreatitis: Pancreatic pseudocyst, walled-off necrosis (WON)
    • Most fluid collections should be followed over time as acute collections can resolve and are unable to be sampled safely with EUS
  • Gallstone pancreatitis:
    • All pts should have cholecystectomy once recovered (recurrence is 25-30%)
    • Performed during initial admission in cases of mild acute pancreatitis
      • Consider age or co-morbid illness precludes fitness for surgery; consult EGS