HEALTH & MEDICINE CALCULATOR
Fena Calculator
A precise tool.
What is the Fena Calculator & How does it work?
The FENa (Fractional Excretion of Sodium) is a useful tool in assessing the severity and type of acute kidney injury. It helps differentiate between prerenal azotemia, intrinsic renal failure, and postrenal obstruction.
FENa is calculated using the formula: [ FENa = left(frac{U_{Na} times PCr}{UCr times P_{Na}}right) times 100 ] where:
FENa is calculated using the formula: [ FENa = left(frac{U_{Na} times PCr}{UCr times P_{Na}}right) times 100 ] where:
FENa = left(frac{U_{Na} times PCr}{UCr times P_{Na}}right) times 100
UNa = Urinary sodium (mmol/L)
PCr = Plasma creatinine (mg/dL)
UCr = Urinary creatinine (mg/dL)
PNa = Plasma sodium (mEq/L)
PCr = Plasma creatinine (mg/dL)
UCr = Urinary creatinine (mg/dL)
PNa = Plasma sodium (mEq/L)
Parameters
Result
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Frequently Asked Questions
How do I calculate FENa?
Use the formula: (U_Na * PCr) / (UCr * P_Na) * 100.
What does FENa stand for?
FENa stands for Fractional Excretion of Sodium.
When is FENa useful in clinical practice?
FENa is useful in assessing the severity and type of acute kidney injury, differentiating between prerenal azotemia, intrinsic renal failure, and postrenal obstruction.
What are the units for U_Na and P_Na in the FENa formula?
U_Na is in mmol/L and P_Na is in mmol/L.
How does a high FENa value indicate kidney function?
A high FENa value (usually >1%) suggests intrinsic renal failure or postrenal obstruction.
What should I consider when interpreting FENa results?
Consider the patient’s fluid status, blood pressure, and other clinical signs to interpret FENa results accurately.
Can FENa be used in all types of kidney injury?
FENa is most useful in acute kidney injury but may not be as reliable in chronic kidney disease or certain electrolyte disorders.
Results are for informational purposes only and do not constitute professional advice.