Impact of a new definition of acute kidney injury based on creatinine kinetics in cardiac surgery patients: a comparison with the RIFLE classification.

Objectives: Acute kidney injury (AKI) after cardiac surgery is associated with adverse patient outcome. A new definition and staging system for AKI based on creatinine kinetics (CKs) has been proposed recently. Their proponents hypothesize that early absolute increases in serum creatinine (sCr) after kidney injury are superior to percentage increases, especially in patients with chronic kidney disease (CKD).