1. What is the Cockroft And Gault Equation?

The Cockroft-Gault equation estimates creatinine clearance (CrCl) from serum creatinine, age, weight, and sex. It is commonly used for drug dosing adjustments in patients with kidney impairment.

2. How Does the Calculator Work?

The calculator uses the Cockroft-Gault equation:

Where:

• \( age \) — Age in years
• \( weight \) — Weight in kilograms
• \( SCr \) — Serum creatinine (mg/dL)
• 0.85 — Female multiplier

Explanation: The equation estimates creatinine clearance based on demographic factors and serum creatinine level.

3. Importance of CrCl Calculation

Details: Creatinine clearance estimation is crucial for adjusting medication dosages in patients with impaired kidney function to avoid toxicity.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: Why use Cockroft-Gault equation?
A: It's widely used for drug dosing adjustments, especially for medications that are renally excreted.

Q2: What are normal CrCl values?
A: Normal is about 95-125 mL/min for young men and 85-115 mL/min for young women, declining with age.

Q3: When should creatinine be measured?
A: Morning fasting sample is ideal, but random samples are acceptable. Avoid testing after meat-heavy meals or vigorous exercise.

Q4: Are there limitations to this equation?
A: Less accurate in extremes of age/weight, obese patients, amputees, and those with rapidly changing kidney function.

Q5: Should ideal body weight be used?
A: For obese patients, some clinicians use adjusted body weight or ideal body weight in the calculation.