Why use it

Well-established severity prediction for acute pancreatitis. Identifies patients at risk for complications. Guides ICU admission decisions.

About

Ranson's criteria predict severity and mortality in acute pancreatitis using 5 parameters at admission and 6 additional parameters at 48 hours (total 11 criteria). A score ≥ 3 suggests severe pancreatitis. While BISAP is simpler and faster, Ranson's remains a well-known scoring system for pancreatitis severity.

When to use

Acute pancreatitis severity assessment
At admission (5 criteria) and at 48 hours (6 additional criteria)

Formula

At admission (1 point each): • Age > 55 • WBC > 16,000 • Glucose > 200 mg/dL • LDH > 350 IU/L • AST > 250 U/L At 48 hours (1 point each): • Hct drop > 10% • BUN increase > 5 mg/dL • Calcium < 8 mg/dL • PaO₂ < 60 mmHg • Base deficit > 4 mEq/L • Fluid sequestration > 6L

Pearls & pitfalls

Ranson requires 48 hours to complete — BISAP can be calculated within 24 hours.
Different criteria exist for gallstone pancreatitis vs. alcoholic pancreatitis — this version is for alcoholic/general.
The admission criteria and 48-hour criteria are SEPARATE — do not use 48-hour values at admission.
Ranson ≥ 3 is the classic threshold for "severe" pancreatitis.
Imaging (CT severity index) is a complementary assessment, not a replacement.

Next steps

Score 0-2: Mild pancreatitis (~1% mortality), likely non-severe. Score 3-5: Moderate (~15% mortality), consider ICU. Score ≥ 6: Severe (~40% mortality), ICU admission, aggressive management.

Evidence

Original study by Ranson et al. (Surg Gynecol Obstet, 1974). Extensively validated. Sensitivity ~65-80% for severe pancreatitis. Limitations include the 48-hour delay for complete scoring.

References

Ranson JH et al. Prognostic signs and the role of operative management in acute pancreatitis. Surg Gynecol Obstet. 1974;139(1):69-81. — link

Ranson's Criteria (Pancreatitis)

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