Acute Pancreatitis

Requires 2 of 3: characteristic pain, lipase >3× ULN, or imaging findings

Symptoms / Associated Sx

  • Severe epigastric pain radiating to the back ("boring" or "band-like")

  • Nausea, vomiting (persistent), abdominal tenderness and guarding

  • Fever (low-grade; high fever suggests infected necrosis or cholangitis)

  • Jaundice if gallstone-related with CBD obstruction

  • Cullen's sign (periumbilical ecchymosis) and Grey Turner's sign (flank ecchymosis) in severe hemorrhagic pancreatitis

Denies

  • Chronic similar pain without acute onset (rules out chronic pancreatitis flare)

  • Fever >38.5°C at onset (raises cholangitis vs. isolated pancreatitis)

  • Peritoneal signs with rigidity (rules out bowel perforation as primary diagnosis)

  • Diarrhea, steatorrhea (rules out exocrine insufficiency from chronic pancreatitis)

Social History (SHx)

Alcohol use, gallstone history, recent ERCP, medications (thiazides, azathioprine, valproate, tetracycline, estrogens), hypertriglyceridemia, family history (hereditary pancreatitis).

Main Etiology

  • Gallstones (~40%), alcohol (~30%), hypertriglyceridemia (TG >1000 mg/dL)

  • Post-ERCP (~3–5%), medications, idiopathic (~15–20%)

  • Hypercalcemia, pancreatic divisum, trauma, autoimmune (IgG4)

Most Common DDx

  • PUD / perforated ulcer (epigastric pain; lipase may be mildly elevated with perforated ulcer; free air on imaging rules in perforation; no lipase >3× ULN in uncomplicated PUD)

  • Acute cholecystitis (RUQ pain; fever; elevated WBC; gallstones on US; normal or mildly elevated lipase; positive Murphy's sign; wall thickening on US)

  • Acute cholangitis (Charcot's triad — fever + jaundice + RUQ pain; CBD dilation + stone; lipase may be elevated with concurrent biliary pancreatitis)

  • Mesenteric ischemia (severe abdominal pain "out of proportion to exam"; older patient with vascular disease; lactate elevated; CT angiography shows mesenteric vessel occlusion)

  • Aortic dissection (sudden tearing back/chest pain; pulse differential; CT aortography confirms; lipase normal)

  • Bowel obstruction (colicky pain; distension; dilated loops on imaging; lipase not elevated)

  • Inferior wall MI (referred epigastric pain; EKG changes; troponin elevated; no lipase elevation)

DATA

  • Lipase (≥3× ULN diagnostic; preferred over amylase)

  • CBC (leukocytosis; hemoconcentration → severity marker); CMP (creatinine, glucose, calcium)

  • LFTs (ALT >3× ULN suggests biliary etiology); triglycerides; CRP (>150 mg/L at 48h = severe)

  • Lactate; RUQ ultrasound (gallstones, biliary dilation)

  • CT abdomen/pelvis with IV contrast (if no improvement at 48–72h or complications suspected; Balthazar/CTSI)

  • MRCP (if CBD stone suspected)

Home Meds

  • Identify and stop offending medication (if drug-induced)

  • Fibrates (hypertriglyceridemia — reassess after acute episode); statins (hold during acute; restart after)

Plan

  • Early enteral nutrition: start PO within 24–48 hrs if tolerated (clear liquid/low-fat → advance as tolerated); NG/NJ feeds if unable to tolerate PO; TPN only if enteral feeding not possible

  • Fluids: LR preferred; 10–20 mL/kg bolus if hypovolemic, then ~1.5 mL/kg/hr (≈150–250 mL/hr); goal UOP >0.5 mL/kg/hr; avoid over-resuscitation

  • Pain: Acetaminophen ± Oxycodone 5–10 mg q4–6h PRN; Hydromorphone 0.2–1 mg IV q2–4h PRN breakthrough

  • Antiemetics PRN

  • Daily CBC, RFP/BMP, Mg, LFTs; replete K, Mg, PO4 as needed

  • Telemetry if severe pancreatitis/SIRS/electrolyte abnormalities

  • Strict I/O, daily weights

  • PT/OT

  • Trend fever curve and hemodynamics

  • Monitor for complications: ARDS, AKI, pancreatic necrosis, infected necrosis, pseudocyst, walled-off necrosis

  • SW/addiction medicine consult if needed

Alcohol-induced:

  • Thiamine 200 mg IV daily x3–5 days → 100 mg PO TID x1–2 weeks

  • Multivitamin

  • Alcohol cessation counseling

Gallstone pancreatitis:

  • GI consult

  • ERCP within 24 hrs if cholangitis or persistent CBD obstruction

  • Surgery consult

  • Cholecystectomy during same admission if mild disease

  • Delay cholecystectomy ~6–10 weeks if severe/necrotizing pancreatitis or large collections

Hypertriglyceridemia-induced (TG >1000):

  • Insulin drip 0.1–0.3 U/kg/hr

  • Glucose q1h; add D5 if glucose <100

  • Continue until TG <500

  • Consider plasmapheresis if severe (TG >2000, organ failure, shock, severe necrosis)

  • Low-fat diet + fenofibrate once tolerating PO

Antibiotics:

  • Not indicated for uncomplicated/sterile pancreatitis

  • Infected necrosis: Meropenem 1 g IV q8h + GI/IR/Surgery consult

  • Cholangitis: Piperacillin-tazobactam + ERCP

Discharge:

  • Tolerating diet, pain controlled on PO meds

  • Low-fat diet

  • Alcohol cessation

  • Cholecystectomy plan if gallstone pancreatitis

  • Fibrate if hypertriglyceridemia

  • GI ± Surgery follow-up 2–4 weeks

Red Flags

  • SIRS ≥2 criteria → severe pancreatitis risk → ICU monitoring

  • Organ failure (Cr >1.9, PaO2/FiO2 <300, SBP <90) → severe acute pancreatitis → ICU

  • Hematocrit >44% (hemoconcentration) → necrotizing pancreatitis risk → aggressive IVF

  • Fever after Day 5 → infected necrosis → CT, FNA, meropenem, interventional drainage

  • Gallstone pancreatitis + fever + jaundice → cholangitis → urgent ERCP within 24h

Senior IM Resident Pearls

  • Revised Atlanta Classification: Mild (no organ failure); Moderate (transient OF ≤48h or local complications); Severe (persistent OF >48h)

  • BISAP score (BUN >25, impaired mental status, SIRS, age >60, pleural effusion) — ≥3 = high mortality; calculated at admission

  • LR over NS guideline-recommended (ACG 2024) — reduces SIRS; avoid in hypercalcemic pancreatitis

  • Lipase preferred over amylase — amylase can be normal in hypertriglyceridemia pancreatitis (TG interferes with assay)

  • Common mistake: Routine prophylactic antibiotics in sterile pancreatitis — multiple RCTs show no benefit

  • Common mistake: Keeping NPO until lipase normalizes — start feeding when clinical symptoms improve

  • ☐ CBC daily

  • ☐ CMP (BUN/Cr, Ca, LFTs) daily

  • ☐ Mg, Phos daily

  • ☐ Triglycerides

  • ☐ ± Lactate (if sick)

  • ☐ Strict I/Os

  • ☐ RUQ ultrasound

  • ☐ CT A/P w/ contrast if:

    • unclear diagnosis

    • no improvement after 2–3 days

    • concern for complications

  • ☐ LR bolus 10 mL/kg (if hypovolemic)

  • ☐ Then LR ~1.5 mL/kg/hr (~3–4 L first 24h)

  • ☐ NPO initially

  • ☐ Start PO within 24–48 hrs → clear → advance as tolerated

  • ☐ Acetaminophen (APAP)

  • ☐ Oxycodone 5–10 mg when PO tolerated

  • ☐ Hydromorphone (Dilaudid) IV for now

  • ☐ Ondansetron (Zofran)

  • ☐ PT/OT

  • ☐ If AUD:

    • ☐ Thiamine 200 mg IV x3–5 days → 100 mg PO TID x1–2 weeks

    • ☐ Multivitamin / prenatal vitamin

  • ☐ GI consult (if obstruction / ERCP consideration)

  • ☐ Surgery → cholecystectomy (if mild gallstone pancreatitis)

  • ☐ IR / Surgery consult for complications (necrosis, pseudocyst)