24th June 2024

Definition

Acute kidney injury (AKI) implies an acute decline in kidney function, leading to a rise in serum creatinine and/or a fall in urine output. The Kidney Disease: Improving Global Outcomes (KDIGO) system for the diagnosis and staging of AKI is widely used to define AKI. This is defined by a rise in serum creatinine (SCr) of ≥ 26.5 μmol/L within 48 hours or SCr rises ≥ 1.5 fold from the reference value, which is known or presumed to have occurred within the preceding 7 days, or urine output of < 0.5ml/kg/h for 6 hours.

Stage	Serum creatinine (SCr) criteria Urine output criteria
1	1.5 to 1.9 times baseline or ≥ 26.5 μmol/L increase in ≤ 48h <0.5 mL/kg/h for 6 – 12 hours
2	2.0 to 2.9 times baseline <0.5 mL/kg/h for ≥ 12 hours
3	≥ 3.0 times baseline or increase in SCr ≥ 26.5 μmol/L to ≥ 354 <0.3 mL/kg/h for ≥ 24 hours μmol/L or initiation of renal replacement therapy irrespective of or anuria for ≥ 12 hours stage

Stage

Serum creatinine (SCr) criteria Urine output criteria

1.5 to 1.9 times baseline or ≥ 26.5 μmol/L increase in ≤ 48h <0.5 mL/kg/h for 6 – 12 hours

2.0 to 2.9 times baseline <0.5 mL/kg/h for ≥ 12 hours

≥ 3.0 times baseline or increase in SCr ≥ 26.5 μmol/L to ≥ 354 <0.3 mL/kg/h for ≥ 24 hours

μmol/L or initiation of renal replacement therapy irrespective of or anuria for ≥ 12 hours

stage

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