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FENa Calculator

Calculate fractional excretion of sodium from urine and plasma sodium and creatinine.

 

 

 

 

FENa (%)

About this calculator

Use this calculator for FENa% = (UNa × PCr) / (PNa × UCr) × 100. Pair urine and plasma sodium in the same concentration unit, and urine and plasma creatinine in the same unit. A <1% vs >2% sketch is taught for pre-renal vs ATN and fails on diuretics. FEUrea is a sibling we skipped.

Urine Na: Urine sodium, same units as plasma Na.

Plasma Na: Plasma sodium.

Urine Cr: Urine creatinine, same units as plasma Cr.

Plasma Cr: Plasma creatinine.

FENa: Fractional excretion of sodium, percent.