1. What is the Cockcroft Formula?

The Cockcroft-Gault formula estimates creatinine clearance from serum creatinine, age, weight, and gender. It provides an assessment of kidney function and is commonly used for medication dosing adjustments.

2. How Does the Calculator Work?

The calculator uses the Cockcroft-Gault formula:

Where:

• \( Age \) — Age in years
• \( Weight \) — Weight in kilograms
• \( Serum\ Creatinine \) — Serum creatinine level in mg/dL
• 0.85 — Female multiplier

Explanation: The equation estimates creatinine clearance based on demographic and laboratory parameters, with adjustment for gender differences.

3. Importance of Creatinine Clearance Calculation

Details: Accurate creatinine clearance estimation is crucial for medication dosing adjustments, particularly for drugs that are renally excreted and have narrow therapeutic windows.

4. Using the Calculator

Tips: Enter age in years, weight in kilograms, serum creatinine in mg/dL, and select gender. All values must be valid (age between 1-120, weight > 0, creatinine > 0).

5. Frequently Asked Questions (FAQ)

Q1: What is the clinical use of Cockcroft-Gault formula?
A: Primarily used for medication dosing adjustments in patients with renal impairment, especially for drugs with renal excretion.

Q2: How does this differ from eGFR calculations?
A: While both assess kidney function, Cockcroft-Gault estimates creatinine clearance, while eGFR equations estimate glomerular filtration rate. They serve different clinical purposes.

Q3: What are the limitations of this formula?
A: Less accurate in extremes of age, obesity, malnutrition, rapidly changing renal function, and patients with unstable creatinine levels.

Q4: When should this formula not be used?
A: Not recommended for pregnant women, children, patients with amputations, or those with rapidly changing kidney function.

Q5: Why is weight included in the calculation?
A: Weight is included because creatinine production is proportional to muscle mass, which correlates with body weight.