Medical calculators

FEUrea

Works Despite Diuretics

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How it is calculated

FEUrea = (urine urea x serum creatinine) / (serum urea x urine creatinine) x 100. Its whole purpose is that it remains valid on diuretics, where FENa is falsely raised and useless - urea handling is largely proximal and less affected by loop and thiazide diuretics.

About

Fractional excretion of urea, answering the same question as FENa but remaining valid in a patient already on diuretics.

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