Pancreatitis, Acute

BASICS

Definition: Acute inflammation of the pancreas, often with local and systemic complications. Reversible if no necrosis or duct disruption.
Key Symptoms: Severe epigastric pain (often radiates to back), nausea, vomiting, ileus.

Alcohol (adults 30–50y)
Gallstones (esp. older adults, median age 69y)
Trauma/surgery, drugs, ERCP, hypertriglyceridemia, hypercalcemia
Autoimmune (type I: ↑IgG4; type II: normal IgG4)
Infections: mumps, coxsackievirus, CMV, EBV, parasites, SARS-CoV-2
Tumors, anatomic abnormalities (pancreas divisum, sphincter of Oddi)
Cystic fibrosis and rare hereditary forms (AD)
Medications (not exhaustive): ACE inhibitors, ARBs, thiazides, azathioprine, steroids, statins, valproic acid, sulfa drugs

Enzymatic autodigestion, interstitial edema, third spacing, local/systemic inflammation.
Complications: necrosis, pseudocyst, duct disruption, pancreatic ascites, vascular injury (splenic vein thrombosis, pseudoaneurysm).

Vitals: tachycardia, hypotension, fever
Abdomen: epigastric tenderness, ileus, peritoneal signs
Rare: Grey Turner (flank) or Cullen (umbilical) sign (hemorrhagic pancreatitis)

Perforated ulcer, cholecystitis, cholangitis, bowel obstruction, MI, aortic aneurysm, mesenteric ischemia

Abdominal US: look for gallstones, bile duct dilation
CT abdomen: confirm diagnosis, assess severity/complications (do not use IV contrast in hypovolemia)
MRCP: evaluate for ductal disease
ERCP: only if evidence of cholangitis or obstruction
EUS: for idiopathic or suspected autoimmune

BISAP Score: BUN >25, impaired mental status, SIRS, age >60, pleural effusion (1 point each)
Ranson Criteria: less commonly used now

Hospitalize most cases; ICU if organ dysfunction
Aggressive IV fluids: bolus 10 mL/kg, then 1.5 mL/kg/hr, target UO 0.5–1.0 mL/kg/hr, max ~4L in 24h
NPO initially, then advance diet as tolerated once pain/ileus resolve (early oral/soft low-fat diet preferred)
Remove inciting meds
NG tube if intractable vomiting
Monitor renal, calcium, glucose, and volume status

ERCP if cholangitis/obstruction
Cholecystectomy before discharge for gallstone pancreatitis (if no necrosis)
Necrosectomy or drainage for infected necrosis
Plasma exchange/insulin for severe hypertriglyceridemic pancreatitis

Discharge criteria: pain controlled, tolerating oral intake, no sepsis/organ failure
Imaging: repeat if persistent symptoms, initial CT showed necrosis/fluid, or labs remain elevated
Monitor for complications: pseudocyst (10%), abscess, splenic vein thrombosis, pseudoaneurysm
Enzyme supplementation: for necrosis/ductal loss with steatorrhea
Diabetes screening: risk of new diabetes after pancreatitis