1. What is the Cockcroft-Gault Equation?

The Cockcroft-Gault equation estimates creatinine clearance (CrCl) which correlates with glomerular filtration rate (GFR). It's commonly used for drug dosing adjustments in patients with renal impairment.

2. How Does the Calculator Work?

The calculator uses the Cockcroft-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 age, weight, serum creatinine, and gender.

3. Importance of CrCl Calculation

Details: CrCl estimation is crucial for adjusting medication dosages in patients with renal impairment to prevent toxicity from drug accumulation.

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 Cockcroft-Gault instead of eGFR?
A: Many drug dosing guidelines are based on CrCl from Cockcroft-Gault rather than eGFR from other equations.

Q2: What are normal CrCl values?
A: Normal is approximately 95-125 mL/min for men and 85-115 mL/min for women.

Q3: Should ideal or actual body weight be used?
A: For obese patients, some guidelines recommend using adjusted body weight: IBW + 0.4 × (TBW - IBW).

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

Q5: When is measured CrCl preferred?
A: For precise drug dosing in critical situations or when the equation is likely inaccurate (e.g., very low muscle mass).