A clinical score to predict acute renal failure after cardiac surgery

J Am Soc Nephrol. 2005 Jan;16(1):162-8. doi: 10.1681/ASN.2004040331. Epub 2004 Nov 24.


The risk of mortality associated with acute renal failure (ARF) after open-heart surgery continues to be distressingly high. Accurate prediction of ARF provides an opportunity to develop strategies for early diagnosis and treatment. The aim of this study was to develop a clinical score to predict postoperative ARF by incorporating the effect of all of its major risk factors. A total of 33,217 patients underwent open-heart surgery at the Cleveland Clinic Foundation (1993 to 2002). The primary outcome was ARF that required dialysis. The scoring model was developed in a randomly selected test set (n = 15,838) and was validated on the remaining patients. Its predictive accuracy was compared by area under the receiver operating characteristic curve. The score ranges between 0 and 17 points. The ARF frequency at each score level in the validation set fell within the 95% confidence intervals (CI) of the corresponding frequency in the test set. Four risk categories of increasing severity (scores 0 to 2, 3 to 5, 6 to 8, and 9 to 13) were formed arbitrarily. The frequency of ARF across these categories in the test set ranged between 0.5 and 22.1%. The score was also valid in predicting ARF across all risk categories. The area under the receiver operating characteristic curve for the score in the test set was 0.81 (95% CI 0.78 to 0.83) and was similar to that in the validation set (0.82; 95% CI 0.80 to 0.85; P = 0.39). In conclusion, a score is valid and accurate in predicting ARF after open-heart surgery; along with increasing its clinical utility, the score can help in planning future clinical trials of ARF.

MeSH terms

  • Acute Kidney Injury / etiology
  • Acute Kidney Injury / mortality*
  • Acute Kidney Injury / therapy
  • Aged
  • Cardiac Surgical Procedures / mortality*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Postoperative Complications / mortality*
  • Predictive Value of Tests
  • ROC Curve
  • Renal Dialysis
  • Risk Factors