Table 1.

RIFLE, AKIN, and ACOG definitions for AKI.

RIFLE25
Risk	1.5-fold increase in serum creatinine OR 25% decrease in GFR OR < 0.5 mL.kg-1.h-1 for > 6 h
Injury	2-fold increase in serum creatinine OR 50% decrease in GFR OR UO < 0.5 mL.kg-1.h-1 for > 12 h
Failure	3-fold increase in serum creatinine OR 75% decrease in GFR OR UO < 0.3 mL.kg-1.h-1 for > 24 h OR no UO for 12 h
Loss of kidney function	Complete loss of kidney function (> 4 weeks)
ESKD	Complete loss of kidney function (> 3 months)
AKIN26
Absolute increase in serum creatinine 0.3 mg.dL-1 or more OR 1.5-fold increase in baseline serum creatinine OR UO < 0.5 mL.kg-1.h-1 for > 6 h
ACOG1
Baseline serum creatinine > 1.1 mg.dL-1 OR 2-fold increase in baseline serum creatinine in the absence of renal disease

ESKD, End Stage Kidney Disease; GFR, Glomerular Filtration Rate; UO, Urinary Output.