The use of RIFLE classification in critically ill patients

Acute kidney injury (AKI) is a common and serious complication in critically ill patients. The mortality rate remains high despite improved renal replacement techniques. A possible cause of the high mortality rate is that intensive care unit (ICU) patients tend to be older and more debilitated than before. Pathophysiological factors associated with AKI are also incriminated in the failure of other organs, indicating that-AKI is often part of a multiple organ failure syndrome. Until recently, practitioners lacked consensus as to the best definition, characterisation and study of acute renal failure. This lack of a standard definition has been a major impediment to progress in clinical and basic research. The introduction of the RIFLE classification (Risk, Injury, Failure, Loss and End-stage kidney disease) has increased the conceptual understanding of AKI syndrome, and the classification has been successfully tested in clinical studies. This article reviews current findings concerning the application of RIFLE criteria for assessing epidemiology and predicting outcome in specific homogeneous critically ill patient groups.