Definition and staging of acute kidney injury according to kidney disease: improving global outcomes criteria
| Stage | Acute kidney injury | Difference | Time frame |
| 1 | Serum creatinine | ≥0.3 mg/dL (26.5 mcmol/l) or | Within 48 hours |
| ≥1.5 times baseline | Within 7 days | ||
| Urine output | <0.5 mL/kg/h | For 6–12 hours | |
| 2 | Serum creatinine | 2.0–2.9 times baseline | |
| Urine output | <0.5 mL/kg/h | For >12 hours | |
| 3 | Start renal replacement therapy | ||
| Serum creatinine | 3.0 times baseline or | Within 7 days | |
| ≥4.0 mg/dL | |||
| Urine output | <0.3 mL/kg/h or | >24 hours | |
| Anuria | >12 hours | ||