Understanding Ranson’s Criteria: A Guide for Assessing Acute Pancreatitis


Ranson’s Criteria is a clinical tool used to assess the severity and predict the prognosis of acute pancreatitis. Developed by Dr. John H. Ranson in 1974, this scoring system helps healthcare providers identify patients at higher risk of complications and mortality, guiding treatment decisions and improving patient outcomes.

What is Ranson’s Criteria?

Ranson’s Criteria consists of 11 prognostic signs, divided into two sets: those assessed at admission and those evaluated within the first 48 hours of hospitalization. Each criterion met adds one point to the patient’s score, with higher scores indicating more severe pancreatitis and a worse prognosis.

For a quick and accurate calculation, you can use our Ranson’s Criteria Calculator.

Ranson’s Criteria at Admission

  • Age: Greater than 55 years
  • White Blood Cell (WBC) Count: Greater than 16,000 cells/mm³
  • Blood Glucose: Greater than 200 mg/dL (11.1 mmol/L)
  • Serum LDH (Lactate Dehydrogenase): Greater than 350 IU/L
  • AST (Aspartate Aminotransferase): Greater than 250 IU/L

Ranson’s Criteria Within 48 Hours

  • Hematocrit Drop: Greater than 10%
  • Blood Urea Nitrogen (BUN) Increase: Greater than 5 mg/dL (1.8 mmol/L) after IV fluid hydration
  • Serum Calcium: Less than 8 mg/dL (2.0 mmol/L)
  • Arterial PO₂: Less than 60 mmHg
  • Base Deficit: Greater than 4 mEq/L
  • Estimated Fluid Sequestration: Greater than 6 liters

Interpreting the Ranson’s Criteria Score

The total Ranson’s score is calculated by summing the points from the criteria met at admission and within the first 48 hours. The score helps predict the severity of pancreatitis and the likelihood of complications or mortality.

  • Score 0-2: Mild pancreatitis, with a low risk of mortality (approximately 1%).
  • Score 3-4: Moderate pancreatitis, with a higher risk of complications and mortality (approximately 15%).
  • Score 5-6: Severe pancreatitis, with a significant risk of complications and mortality (approximately 40%).
  • Score 7-11: Very severe pancreatitis, with a very high risk of mortality (approximately 100%).

Clinical Significance of Ranson’s Criteria

Ranson’s Criteria is valuable for several reasons:

  • Early Risk Stratification: By evaluating specific clinical and laboratory parameters, healthcare providers can identify patients at high risk early in the course of the disease.
  • Guiding Treatment Decisions: Patients with higher Ranson’s scores may require more intensive monitoring, aggressive fluid resuscitation, and advanced supportive care.
  • Predicting Outcomes: The criteria provide an estimate of the likelihood of complications and mortality, helping to inform discussions with patients and their families about prognosis.

Limitations of Ranson’s Criteria

While Ranson’s Criteria is a useful tool, it has some limitations:

  • Timing of Assessment: The full score cannot be calculated until 48 hours after admission, which may delay complete risk stratification.
  • Complexity: The criteria require multiple laboratory tests and clinical evaluations, which may not always be feasible in all healthcare settings.
  • Evolving Standards: Advances in medical care and newer prognostic tools, such as the APACHE II score and CT Severity Index, have provided additional methods for assessing pancreatitis severity.