Fractional Excretion of Sodium

The Fractional Excretion of Sodium calculator computes the percent of sodium excretion based on the sodium and creatinine levels of urine and serum.

INSTRUCTIONS:Enter the following:

• (UNa) Urine Sodium Level
• (UCr) Urine Creatinine Level
• (SNa) Serum Sodium Level
• (SCr) Serum Creatinine Level

Fractional Excretion of Sodium (FENa): The calculator return excretion level as a percentage.

The Math / Science

The formula for the Fractional Excretion of Sodium is:

`FENa = (UNa * SCr)/(SNa * UCr)`

where:

• FENa  = Fractional Excretion of Sodium
• UNa = Urine Sodium Level
• UCr = Urine Creatinine Level
• SNa = Serum Sodium Level
• SCr = Serum Creatinine Level