Online Clinical Calculator: Fractional Excretion of Sodium
Medstudents' Homepage
Plasma
Na
mEq/L
Plasma
Creatinine
mg/dL
Urine
Na
mEq/L
Urine
Creatinine
mg/dL
Fractional Excretion of Sodium =
%
Fractional Excretion Na = 100 x (U
Na
x P
Creat
)/(P
Na
x U
Creat
)
Useful for distinguishing between prerenal failure and intrinsic renal failure.
With prerenal failure, FENa is usually < 1%. With intrinsic failure, FENa is usually > %1
Online Clinical Calculator: Fractional Excretion of Sodium
