Fractional Excretion of Sodium (FENa)

Synonyms

• FENA
• LAB14020

Cerner Name

Fractional Excretion of Sodium (FENa)

Clinical Info

In patients with AKI, the FENa is often used to assist in differentiating prerenal disease from acute tubular necrosis (ATN). The Fractional excretion of sodium (FENa) require a serum and random urine specimen to both be collected within a short period of time from each other.

Specimen Sources

Urine, Clean Catch

Specimen Types

Urine

Specimen Volume

Container

Urine-Yellow Top

Collection Instructions

Container/Tube: Gold top tube AND Urine Container
Specimen: 1 mL serum and 1 mL Random Urine

Transport Instructions

Specimen Stability

Methodology

Calculation
The calculated values are:
FENa % = (Urine Sodium x Serum Creatinine) / (Serum Sodium x Urine Creatinine) x100.
FEUrea % = = (Urine Urea x Serum Creatinine) / (Serum Urea x Urine Creatinine) x100.

Days Performed

Performing Laboratories

Northwell Health Laboratories

CPT

PDM

231040

Results

Result Interpretation

Forms