Criteria for staging AKI Stage 1: Serum creatine; 1.5-1.9 times baseline or > 0.3 mg/dl increase, Urine output; < 0.5/kg/hour for 6-12 hours Stage 2: Serum creatinine; 2-2.9 times baseline, Urine Output; < 0.5/kg/hour for > 12 hours Stage 3: Serum creatinine; 3.0 times baseline or initiation of renal replacement therapy or in patients < 18 years, decrease in eGFR to < 35 ml/min per 1.73 m2 , Urine output; < 0.3/kg/hour 24 hours or more or anuria for 12 or more hours