Ranson Criteria Calculator
Predict acute pancreatitis severity using Ranson admission and 48-hour criteria. Enter values for instant results with step-by-step formulas.
Formula
Ranson Score = Sum of positive criteria (0-11)
The Ranson score is the total count of positive criteria from 5 admission parameters and 6 parameters assessed at 48 hours. Score 0-2: mild (<1% mortality), 3-4: moderate (~15%), 5-6: severe (~40%), 7+: critical (>99%).
Worked Examples
Example 1: Moderate Severity Pancreatitis
Problem: A 60-year-old patient with alcoholic pancreatitis has WBC 18,000, glucose 250, LDH 300, AST 200 at admission. At 48 hours: Hct drop 8%, BUN rise 3, Ca 7.5, PaO2 70, base deficit 3, fluid 4L.
Solution: Admission criteria met: Age > 55 (+1), WBC > 16,000 (+1), Glucose > 200 (+1)\nLDH 300 < 350 (0), AST 200 < 250 (0)\nAdmission score: 3\n48-hour criteria: Calcium < 8 (+1)\nHct 8% not > 10 (0), BUN 3 not > 5 (0), PaO2 70 not < 60 (0)\n48-hour score: 1
Result: Total Ranson Score: 4 | Severity: Moderate | Mortality: ~15%
Example 2: Severe Gallstone Pancreatitis
Problem: A 75-year-old with gallstone pancreatitis: WBC 20,000, glucose 300, LDH 500, AST 400. At 48h: Hct drop 15%, BUN rise 8, Ca 6.5, PaO2 55, base deficit 7, fluid 8L.
Solution: Gallstone admission: Age > 70 (+1), WBC > 18,000 (+1), Glucose > 220 (+1), LDH > 400 (+1), AST > 250 (+1)\nAdmission score: 5\n48-hour: All six criteria met (+6)\nHct > 10, BUN > 2, Ca < 8, PaO2 < 60, BD > 5, Fluid > 4L
Result: Total Ranson Score: 11/11 | Severity: Critical | Mortality: > 99%
Frequently Asked Questions
What are Ranson criteria and when are they used?
Ranson criteria are a clinical prediction tool used to assess the severity and prognosis of acute pancreatitis. Developed by Dr. John Ranson in 1974, this scoring system uses 11 parameters measured at two time points: five criteria assessed at the time of hospital admission and six additional criteria assessed at 48 hours after admission. The criteria were originally developed for alcohol-induced pancreatitis but have been modified for gallstone pancreatitis as well. Ranson criteria remain one of the most widely recognized severity scoring systems for acute pancreatitis, though newer tools like the BISAP score and APACHE II have gained popularity due to their ability to be calculated earlier. The total score ranges from 0 to 11, with higher scores indicating more severe disease and higher mortality risk.
What are the 48-hour criteria for Ranson score?
The six criteria assessed at 48 hours after admission measure the body's response to pancreatic inflammation and reflect ongoing organ damage. These include: hematocrit decrease of more than 10 percentage points indicating fluid loss into the retroperitoneum, blood urea nitrogen (BUN) increase of more than 5 mg per dL suggesting renal impairment from hypovolemia, serum calcium less than 8 mg per dL as calcium is consumed through saponification of peripancreatic fat, arterial partial pressure of oxygen (PaO2) less than 60 mmHg indicating acute respiratory distress, base deficit greater than 4 mEq per L reflecting metabolic acidosis from tissue hypoperfusion, and estimated fluid sequestration greater than 6 liters demonstrating massive third-spacing of fluid. Each positive criterion adds one point to the total score.
How do Ranson criteria predict mortality in acute pancreatitis?
Ranson criteria provide a stepwise mortality prediction based on the total number of positive criteria out of the maximum 11 points. A score of 0 to 2 criteria indicates mild pancreatitis with a predicted mortality of less than 1 percent, and these patients typically recover with conservative management including bowel rest and intravenous fluids. A score of 3 to 4 criteria correlates with approximately 15 percent mortality and suggests moderate severity requiring close monitoring. A score of 5 to 6 criteria indicates severe pancreatitis with about 40 percent mortality, necessitating intensive care unit admission. A score of 7 or more criteria is associated with mortality approaching or exceeding 99 percent, indicating critical illness with multiorgan failure. However, it is important to note that these mortality estimates were derived from historical data and modern critical care has improved outcomes.
What are the limitations of Ranson criteria?
Ranson criteria have several important limitations that clinicians should consider. First, the complete score cannot be calculated until 48 hours after admission, delaying risk stratification during a critical early treatment window. Second, the criteria were developed from a specific patient population in the 1970s and may not fully generalize to modern diverse populations. Third, the scoring system is not validated for recurrent pancreatitis episodes or chronic pancreatitis exacerbations. Fourth, it provides a static score at 48 hours and does not account for dynamic changes in clinical status thereafter. Fifth, the criteria have moderate sensitivity and specificity, meaning some patients with low scores may still develop complications, and some with high scores may recover well. Modern alternatives like the BISAP score can be calculated within the first 24 hours, and the revised Atlanta classification provides a more comprehensive framework for severity assessment.
Is my data stored or sent to a server?
No. All calculations run entirely in your browser using JavaScript. No data you enter is ever transmitted to any server or stored anywhere. Your inputs remain completely private.
Is Ranson Criteria Calculator free to use?
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