Fractional Excretion of Bicarbonate

The Fractional Excretion of Bicarbonate (FEB) is a test used to assess the kidney’s ability to handle bicarbonate, which is vital for maintaining acid-base balance in the body. It helps determine whether the kidneys are properly conserving or excreting bicarbonate, which can be crucial in diagnosing conditions like metabolic acidosis, metabolic alkalosis, or renal tubular acidosis (RTA). The FEB calculator uses serum bicarbonate, urine bicarbonate, and serum creatinine values to calculate the fraction of bicarbonate excreted in urine.

• Evaluate Renal Function: Helps assess the kidneys' ability to conserve or excrete bicarbonate, a critical process in maintaining acid-base balance.
• Diagnose Acid-Base Disorders: Useful in diagnosing conditions like metabolic acidosis or alkalosis.
• Monitor Treatment Progress: Tracks the effectiveness of treatments for metabolic disorders or kidney diseases.
• Differentiate Between Renal and Extrarenal Causes: Helps distinguish whether bicarbonate disturbances are due to kidney dysfunction or other systemic issues.