Acute pancreatitis: workup and management
Acute pancreatitis is diagnosed with two of three: typical epigastric pain, lipase or amylase >3× the upper limit of normal, or characteristic imaging. Find the cause (gallstones and alcohol are the most common), predict severity, give moderate goal-directed lactated Ringer's, feed early, and avoid prophylactic antibiotics.
Working diagnosis
Adult · US guidelines
Draft · awaiting physician review
01Orient
What's new in the evidence
- ACG 2024 guideline: moderate goal-directed fluids (10 mL/kg bolus only if hypovolemic, then ≤1.5 mL/kg/h); lactated Ringer's preferred
- WATERFALL (2022): aggressive fluid resuscitation caused more fluid overload without better outcomes
- APEC (2020): urgent ERCP does not help predicted-severe gallstone pancreatitis without cholangitis
- No prophylactic antibiotics, even in necrotizing pancreatitis; feed early
Differential diagnoses
- Gallstone pancreatitis
- Alcohol-associated pancreatitis
- Hypertriglyceridemia (TG >1000 mg/dL), hypercalcemia, drugs, post-ERCP
- Perforated viscus (can't miss)
- Mesenteric ischemia (can't miss)
- Inferior MI (can't miss)
- Cholangitis (can't miss), cholecystitis, peptic ulcer disease
02Assess
Risk scores and decision tools
- BISAP (≥3 predicts severe disease)
- SIRS at admission and 48 hours
- Revised Atlanta classification (mild, moderately severe, severe)
- BUN and hematocrit trends in the first 24–48 hours
Key history questions
- Onset and character of pain, radiation to back
- Alcohol use; prior gallstones or biliary colic
- New drugs (e.g., azathioprine, valproate, GLP-1 agonists, thiazides)
- Prior pancreatitis, recent ERCP
- Fever, jaundice (cholangitis)
Examination findings
- Epigastric tenderness, guarding
- Tachycardia, hypotension, tachypnea, hypoxia (severe disease)
- Jaundice; Cullen or Grey Turner signs (late, uncommon)
03Investigate
Initial investigations
- Lipase
- CBC, BMP, BUN, calcium, LFTs, triglycerides
- Lactate, blood gas if unwell
- Right upper quadrant ultrasound for gallstones
- ECG; pregnancy test where relevant
Advanced investigations
- Contrast CT only if the diagnosis is uncertain or no improvement after 48–72 hours
- MRCP or EUS if bile duct stones are suspected but not confirmed
- IgG4 and genetic testing for recurrent idiopathic disease
04Treat
Immediate management
- Moderate goal-directed lactated Ringer's: 10 mL/kg bolus if hypovolemic, then about 1.5 mL/kg/h, reassessing frequently
- Avoid aggressive fluids (≥20 mL/kg bolus with 3 mL/kg/h) in non-hypovolemic patients
- Analgesia, including opioids when needed
- Urgent ERCP (within 24 hours) for cholangitis
First-line treatment
- Early oral feeding within 24–48 hours as tolerated; a low-fat solid diet is fine
- Enteral (not parenteral) nutrition if oral intake is not possible
- No prophylactic antibiotics, even in severe or necrotizing disease
- Same-admission cholecystectomy for mild gallstone pancreatitis
Second-line treatment
- Antibiotics only for proven or strongly suspected infection (cholangitis, infected necrosis)
- Infected necrosis: delay intervention, then step-up drainage or endoscopic necrosectomy
- Hypertriglyceridemia: insulin infusion; plasmapheresis in selected cases
Specialist referrals
- Gastroenterology for ERCP or complicated disease
- General surgery for cholecystectomy
- ICU for organ failure
05Disposition
Admission criteria
- Almost all patients with acute pancreatitis
- SIRS, organ failure, BUN rising, hematocrit >44% or BISAP ≥3 suggest severe disease
Safe discharge criteria
- Pain controlled on oral analgesia
- Tolerating diet
- Cause identified and addressed (cholecystectomy planned or done)
Follow-up timing
- Clinic in 2–4 weeks; imaging at 4+ weeks if collections
Patient instructions
- Stop alcohol completely if alcohol-related
- Return for worsening pain, fever, jaundice or vomiting
Monitoring
- Vitals, urine output, oxygen saturation
- BUN and creatinine at 24 and 48 hours
Clinical pearls and pitfalls
- Lipase level does not correlate with severity
- Persistent organ failure >48 hours defines severe pancreatitis (revised Atlanta)
- No cause found: check triglycerides, calcium and drug list, then image for small stones or tumor in older patients
RefGuidelines and landmark evidence
For education only. Typical adult starting points; confirm doses against renal function, allergies, interactions and your institution's protocols. Not a substitute for clinical judgment or senior review.