From the Guidelines
Ranson's criteria are a set of prognostic indicators used to assess the severity of acute pancreatitis at admission and within 48 hours, with a mortality risk increasing with the number of positive criteria. At admission, five criteria are evaluated: age over 55 years, white blood cell count greater than 16,000/mm³, blood glucose greater than 200 mg/dL, serum LDH greater than 350 IU/L, and AST greater than 250 IU/L. Within 48 hours, six additional criteria are assessed: hematocrit decrease greater than 10%, BUN increase greater than 5 mg/dL, serum calcium less than 8 mg/dL, arterial PO₂ less than 60 mmHg, base deficit greater than 4 mEq/L, and estimated fluid sequestration greater than 6 L. The criteria are used to predict the severity of acute pancreatitis, with the number of positive criteria corresponding to an increased mortality risk: 0-2 criteria indicates approximately 1% mortality risk, 3-4 criteria about 15% risk, 5-6 criteria about 40% risk, and 7 or more criteria indicates a mortality risk of approximately 100% 1. Some of the key points to consider when using Ranson's criteria include:
- The criteria require 48 hours for complete assessment, which may delay treatment in critically ill patients 1
- Other scoring systems, such as APACHE II and BISAP, can be calculated earlier and provide similar prognostic value 1
- The predictive performance of Ranson's criteria and other scoring systems can be variable, and no systematic review has included studies assessing the accuracy of different clinical scoring systems used to predict severity and mortality in people with acute pancreatitis 1. It is essential to consider these factors when using Ranson's criteria to assess the severity of acute pancreatitis and make informed decisions about patient care.
From the Research
Ranson's Criteria
Ranson's criteria are a widely used method to evaluate the severity of acute pancreatitis (AP) 2. The criteria include multiple factors that are measured on admission and again within 48 hours.
Factors Included in Ranson's Criteria
The factors included in Ranson's criteria are:
- Age
- White blood cell count
- Blood glucose
- Serum lactate dehydrogenase (LDH)
- Serum aspartate aminotransferase (AST)
- Blood urea nitrogen (BUN)
- Serum calcium
- Arterial oxygen tension (PaO2)
- Base deficit
- Fluid sequestration
- Glasgow coma scale
Assessment of Severity
The severity of acute pancreatitis is assessed based on the number of positive Ranson variables. A higher number of positive variables indicates a more severe disease 3.
Prediction of Outcomes
Ranson's criteria have been shown to accurately predict outcomes in patients with severe acute pancreatitis, including mortality, need for operative debridement, and need for an ICU stay for longer than 7 days 3.
Comparison with Other Scoring Systems
Ranson's criteria have been compared with other scoring systems, such as the APACHE III score, and have been found to be more accurate in predicting outcomes in patients with severe acute pancreatitis 3.
Clinical Application
Ranson's criteria are widely used in clinical practice to assess the severity of acute pancreatitis and to predict outcomes 4. They are also used to guide treatment decisions and to monitor the progress of patients with acute pancreatitis.
Limitations
While Ranson's criteria are widely used, they have some limitations. They require multiple measurements over a period of 48 hours, which can delay diagnosis and treatment 2. Additionally, they may not be as accurate in predicting outcomes in patients with mild acute pancreatitis.
Correlation with Other Markers
Ranson's criteria have been correlated with other markers, such as red cell distribution width (RDW), which has been shown to be a useful marker in predicting mortality in patients with acute pancreatitis 2.
CT Evaluation
Ranson's criteria can be used in combination with CT evaluation to assess the severity of acute pancreatitis 5. The presence of non-perfused areas in the pancreas at contrast-enhanced computed tomography is indicative of pancreatic necrosis and portends an unfavorable prognosis 4.