Ranson Criteria

Article Author:
Hajira Basit
Article Author (Archived):
Gordon Ruan
Article Editor:
Sandeep Mukherjee
Updated:
7/1/2019 4:44:46 PM
PubMed Link:
Ranson Criteria

Introduction

The original Ranson's criteria is a scoring system that uses 11 parameters to assess the severity of acute pancreatitis. The 11 parameters are age, white blood cell count (WBC), blood glucose, serum aspartate transaminase (AST), serum lactate dehydrogenase (LDH), serum calcium, fall in hematocrit, arterial oxygen (PaO2), blood urea nitrogen (BUN), base deficit, and sequestration of fluids.[1][2][3]

The criteria are named after Dr. John Ranson, a surgeon and leading figure on the pancreas during the 20th century. Dr. Ranson introduced the criteria in his 1974 paper: Prognostic signs and the role of operative management in acute pancreatitis. The study had a population of 100 patients with acute pancreatitis. Eleven objective findings were determined to be of significant prognostic value for predicting severe acute pancreatitis. These objective findings are the 11 parameters mentioned above that makeup Ranson's criteria. It should be noted that there is also a modified Ranson's criteria. The criteria with 11 parameters are used to score alcoholic pancreatitis while the modified criteria have 10 parameters that are used to score gallbladder pancreatitis.[3][4][5]

Ranson's criteria are one of the earliest scoring systems to assess the severity of acute pancreatitis and continue to be widely used. Since its inception, there are at least 17 other scoring systems that have been validated.

Function

Ranson's criteria are used to predict severity and mortality of acute pancreatitis. Five parameters are assessed on admission, and the other six are assessed at 48 hours post admission. One point is given for each positive parameter for a maximum score of 11. The modified criteria have a max score of 10. Five parameters assessed on admission and the other 5 at the 48-hour mark.[6][7][8]

The criteria with 11 parameters are used to assess the severity of alcoholic pancreatitis. The 5 parameters on admission are age older than 55 years, WBC count greater than 16,000 cells/mm^3, blood glucose greater than 200 mg/dL (11 mmol/L), serum AST greater than 250 IU/L, and serum LDH greater than 350 IU/L. At 48 hours, the remaining 6 parameters are: serum calcium less than 8.0 mg/dL (less than 2.0 mmol/L), hematocrit fall greater than 10%, PaO2 less than 60 mmHg, BUN increased by 5 or more mg/dL (1.8 or more mmol/L) despite intravenous (IV) fluid hydration, base deficit greater than 4 mEq/L, and sequestration of fluids greater than 6 L.

The modified Ranson's criteria are used to assess gallstone pancreatitis. The five parameters on admission are age older than 70 years, WBC greater than 18,000 cells/mm^3, blood glucose greater than 220 mg/dL (greater than 12.2 mmol/L), serum AST greater than 250 IU/L, and serum LDH greater than 400 IU/L. At 48 hours, the remaining 5 parameters are serum calcium less than 8.0 mg/dL (less than 2.0 mmol/L), hematocrit fall greater than 10%, BUN increased by 2 or more mg/dL (0.7 or more mmol/L) despite IV fluid hydration, base deficit greater than 5 mEq/L, and sequestration of fluids greater than 4 L.

Score Interpretation

  • 0 to 2 points: Mortality 0% to 3%
  • 3 to 4 points: 15%
  • 5 to 6 points: 40% 
  • 7 to 11: nearly 100%

Issues of Concern

One limitation of Ranson's criteria is that other scoring systems are superior in either sensitivity or specificity, In a 2016 meta-analysis, a Ranson's score greater than 2 had a median sensitivity and specificity of 90% and 67.4% respectively. In this same meta-analysis, other scoring systems had better sensitivity or specificity. For example, APACHE-II score greater than 7 had a 100% median sensitivity, while BISAP score greater than 2 had 87.6% median specificity. Another meta-analysis of acute pancreatitis severity scores showed that a Ranson score of greater than 2 has a sensitivity of 86.6% and specificity of 87.2%. Ranson et al. also showed a Ranson score greater than 2 had a sensitivity of 84.2% and specificity of 89.8%.

The second limitation is that the score and severity of acute pancreatitis cannot be determined until 48 hours have passed since admission. This limits its utility in time-sensitive situations like the emergency department. Also, there are 11 parameters, which makes it difficult to use conveniently. Other scoring systems like APACHE-II can be applied at any time and is the scoring system used in critical care. The Bedside Index of Severity in Acute Pancreatitis (BISAP) is another scoring system that can be used at any time and is utilized by emergency medicine physicians.

The third limitation is that the study group in Ranson et al. consisted of an age range of approximately 30 to 75 years old. As a result, Ranson's criteria cannot be used for a pediatric or adolescent population. This was studied in Lautz et al., which showed that the Ranson's criteria had a sensitivity 51.8% and negative predictive value of 83.2%.

Clinical Significance

Ranson's criteria are primarily used in the inpatient setting. A Ranson score of 0 or 1 predicts that complications will not develop and that mortality will be negligible. A score of 3 or greater predicts severe acute pancreatitis and possible mortality. Severe acute pancreatitis is defined by the presence of any organ failure or local pancreatic complications such as pseudocyst, abscess, or necrosis.

Other Issues

Because of the drawbacks of the Ranson criteria, other factors are also used to assess the severity of acute pancreatitis. An elevated BUN on admission has been found to be associated with an increase in the severity of acute pancreatitis and/or risk fo death. It is believed that the elevated BUN is a reflection of intravascular volume depletion, which is mediated by inflammatory mediators in response to the acute inflammation. The APACHE score has one major advantage over Ranson criteria in that it can be used to evaluate the patient at any time point of admission. However, the one major drawback of the APACHE score is that it is labor intensive.

The one laboratory parameter which is often used to stage acute pancreatitis is the hematocrit. Hematocrit greater than 47% on admission has been shown to be a good predictor of pancreatic necrosis. Other markers also used to stage acute pancreatitis include levels of CRP and interleukin-6. Many other biological markers have shown promise in predicting the severity of acute pancreatitis (e.g., trypsinogen activation peptide, phospholipase A2, and polymorphonuclear elastase) but not all are better than using CRP.

It is important to understand that imaging is not indicated to assess a patient with mild acute pancreatitis unless the patient is suspected of having a malignancy. However, CT scan of the abdomen is always indicated in patients with severe acute pancreatitis and is the imaging modality of choice in patients with complications. The CT scan is rarely needed within the first three days of admission unless the diagnosis is in doubt because most inflammatory alterations are often not visible on the scan at this time.

Finally, in some patients with severe acute pancreatitis, image-guided aspiration may be required to differentiate sterile necrosis from a purulent infection.

Enhancing Healthcare Team Outcomes

The Ranson criteria have been used to assess the severity of acute pancreatitis for several decades. There continues to be argument about its sensitivity and specificity. However, it is vital that patients with acute pancreatitis be assessed by a multidisciplinary team that includes a gastroenterologist, surgeon, endocrinologist and a radiologist. Patients with moderate to severe acute pancreatitis are best monitored by ICU nurses. There are other scoring criteria that can also be used to assess the severity of the condition. One should not place reliance on Ranson criteria but also use clinical acumen.[9]


References

[1] Kothari S,Kalinowski M,Kobeszko M,Almouradi T, Computed tomography scan imaging in diagnosing acute uncomplicated pancreatitis: Usefulness {i}vs{/i} cost. World journal of gastroenterology. 2019 Mar 7;     [PubMed PMID: 30862996]
[2] Y─▒lmaz EM,Kandemir A, Significance of red blood cell distribution width and C-reactive protein/albumin levels in predicting prognosis of acute pancreatitis. Ulusal travma ve acil cerrahi dergisi = Turkish journal of trauma     [PubMed PMID: 30516251]
[3] Waller A,Long B,Koyfman A,Gottlieb M, Acute Pancreatitis: Updates for Emergency Clinicians. The Journal of emergency medicine. 2018 Dec;     [PubMed PMID: 30268599]
[4] Hagjer S,Kumar N, Evaluation of the BISAP scoring system in prognostication of acute pancreatitis - A prospective observational study. International journal of surgery (London, England). 2018 Jun;     [PubMed PMID: 29684670]
[5] Shah AS,Gupta AK,Ded KS, Assessment of PANC3 Score in Predicting Severity of Acute Pancreatitis. Nigerian journal of surgery : official publication of the Nigerian Surgical Research Society. 2017 Jan-Jun;     [PubMed PMID: 28584513]
[6] Kim YJ,Kim DB,Chung WC,Lee JM,Youn GJ,Jung YD,Choi S,Oh JH, Analysis of factors influencing survival in patients with severe acute pancreatitis. Scandinavian journal of gastroenterology. 2017 Aug;     [PubMed PMID: 28388866]
[7] Cucuteanu B,Prelipcean CC,Mihai C,Dranga M,Negru D, SCORING IN ACUTE PANCREATITIS: WHEN IMAGING IS APPROPRIATE?. Revista medico-chirurgicala a Societatii de Medici si Naturalisti din Iasi. 2016 Apr-Jun;     [PubMed PMID: 27483698]
[8] Kuo DC,Rider AC,Estrada P,Kim D,Pillow MT, Acute Pancreatitis: What's the Score? The Journal of emergency medicine. 2015 Jun;     [PubMed PMID: 25843921]
[9] Wahab S,Khan RA,Ahmad I,Wahab A, Imaging and clinical prognostic indicators of acute pancreatitis: a comparative insight. Acta gastroenterologica Latinoamericana. 2010 Sep;     [PubMed PMID: 21049773]