Table 1.

Definition and staging of AKI by RIFLE (Risk, Injury, Failure, Risk, Loss, and ESRD) classification and subacute kidney injury

Classification per Type of Kidney Injury Criteria
AKI
 Risk1.5–1.9 times baseline within 7 d
 Injury2.0–2.9 times baseline within 7 d
 Failure3.0 times baseline within 7 d or increase in serum creatinine to ≥4.0 mg/dl with an acute rise of ≥0.5 mg/dl within 7 d
Subacute kidney injury
 Mild1.5–1.9 times baseline in >7 d
 Moderate2.0–2.9 times baseline in >7 d
 Severe3.0 times baseline in >7 d or increase in serum creatinine to ≥4.0 mg/dl with a rise of ≥0.5 mg/dl in >7 d