ARF classification


We (CUH EM) have traditionally use the RIFLE classification as the AKIN creatinine levels should ideally be taken at 48°.

In RIFLE or AKIN classification, please use either creatinine level or urine output levels to classifiy acute kidney injury level (and indicate which you are using).

RIFLE classification

Stage Creatinine   Urine output
Risk renal failure Cr. x 1.5 normal or UO < 0.5ml / kg / hour for 6 hours
Injury to kidney Cr. x 2 normal or UO < 0.5ml / kg / hour for 12 hours
Failure of kidney fxn Cr. x 3 normal or Anuric for 12 hours
Loss kidney fxn Need renal replacement therapy x 4 weeks
End stage renal disease Need renal replacement therapy for > 13 weeks

AKIN classification

Stage Creatinine criteria   Urine output criteria
1 Cr. x 1.5 - 2 baseline or <0.5 mL/kg/h for 6 hours
2 Cr. x 2 -3 from baseline or <0.5 mL/kg/h for 12 hours
3 Cr. x 3 baseline OR
Cr. ≥ 354 µmol/l with an acute ↑ > 44 µmol/l OR need RRT
or UO <0.3 mLl/kg/h for 24° OR
anuria for 12 h OR
need for RRT

Content by Dr Íomhar O' Sullivan 25/11/2004. Last review Dr. ÍOS 3/06/15