A prospective study indicating that fractional excretion of sodium is a good marker for fluid loss

Mahesh M. G., Prasanna Kumar H. R., Srinath K. M., Ashok P., Shilpa Avarebeel


Background: Pre-renal failure, a reversible form of acute renal failure (ARF), accounts for 60-70% of all cases of ARF. To study the factors affecting fractional excretion of sodium (FENa) in patients with pre-renal failure.

Methods: The study involved patients with pre-renal failure, admitted in a multi-speciality hospital in south India for a period of two years. The demographic and clinical data were collected using a standard pro forma. The correlation between FENa and factors such as age, diabetes mellitus, fluid loss, fever, urine output and creatinine of pre-renal failure were statistically evaluated.

Results: The prospective study involved 24 patients diagnosed as pre-renal failure with a mean age of 52.75±18.78. The subjects included 14 males and 10 females, with a median FENa of 0.55 (0.10-0.90). A moderate negative correlation was observed between FENa and fluid loss in pre-renal failure patients (r -0.646, P=0.0007).

Conclusions: The level of FENa may assist in estimating fluid loss in patients with pre-renal failure.


Acute tubular necrosis, FENa, Pre-renal failure

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