Fractional Excretion of Sodium (FENa)

Serum Sodium:
Serum Creatinine:
Urine Sodium:
Urine Creatinine:


Fractional Excretion of Sodium (FENa):
Renal Failure Index (RFI):

Computational notes

Fractional Excretion of sodium (FENa)

Fractional Excretion of sodium (FENa) is the amount of salt (sodium) that leaves the body through urine compared to the amount filtered and reabsorbed by the kidney. FENa is calculated as follows:

Fractional Excretion of sodium (FENa)

Renal Failure Index (RFI)

Renal Failure Index (RFI)

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