The Fractional Excretion of Sodium (FENa) determines if renal failure is due to pre-renal, intrinsic, or post-renal pathology.

FENa is calculated in two parts—figuring out how much sodium is excreted in the urine, and then finding its ratio to the total amount of sodium that passed through (aka "filtered by") the kidney. [citation …

Oct 30, 2024 · The fractional excretion of sodium (FENa) measures the percent of filtered sodium that is excreted in the urine. This calculation is used to help differentiate prerenal disease (decreased …

To accurately interpret FENa, patients should not have recently received diuretics. FENa is greater than 1% and usually greater than 3% with acute tubular necrosis and severe obstruction of the urinary …

Learn how the fractional excretion of sodium (FENa) test helps diagnose kidney issues, including acute kidney injury. Understand its importance, procedure, and results.

Jul 24, 2025 · Fractional Excretion of Sodium (FENa) quantifies the percentage of filtered sodium excreted in urine, helping differentiate causes of acute kidney injury (AKI).

Dec 31, 2023 · Fractional excretion of sodium (FENa) is not a test. Instead it is a calculation based on the concentrations of sodium and creatinine in the blood and urine. Urine and blood chemistry tests …

Oct 31, 2025 · The fractional excretion of sodium (FENa) measures the percent of filtered sodium that is excreted in the urine. The FENa is the most accurate screening test to help differentiate between …

May 7, 2025 · Use our FeNa Calculator to quickly determine fractional excretion of sodium (FeNa), aiding in the diagnosis of prerenal vs intrinsic renal causes of AKI.

FENa is the percentage of the sodium filtered by the kidney, which is excreted in the urine. This value is widely used to help differentiate pre-renal disease (decreased renal perfusion) from acute tubular …