Body Surface Area (BSA) Calculator

Mosteller Formula:

\[ BSA = \sqrt{\frac{W \times H}{3600}} \]

Body Surface Area (m²):

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1. What is Body Surface Area (BSA)?

Definition: BSA is the calculated surface area of a human body, often used in medical practice for drug dosage calculations and physiological measurements.

Purpose: It provides a more accurate measurement than body weight alone for determining proper medication dosages and other medical applications.

2. How Does the Mosteller Formula Work?

The calculator uses the Mosteller formula:

\[ BSA = \sqrt{\frac{W \times H}{3600}} \]

Where:

\( BSA \) — Body Surface Area (square meters)
\( W \) — Weight (kilograms)
\( H \) — Height (centimeters)

Explanation: The formula calculates the square root of the product of weight and height divided by 3600 to estimate body surface area.

3. Importance of BSA Calculation

Details: BSA is used in chemotherapy dosing, calculating cardiac index, determining glomerular filtration rate, and other medical applications where body size affects outcomes.

4. Using the Calculator

Tips: Enter weight in kilograms and height in centimeters. Both values must be greater than 0 for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why use BSA instead of weight for medication dosing?
A: BSA accounts for both height and weight, providing a better estimate of metabolic mass than weight alone.

Q2: What's the average BSA for adults?
A: The average BSA is about 1.7 m² for adult men and 1.6 m² for adult women.

Q3: Are there other BSA formulas?
A: Yes, other common formulas include Du Bois, Haycock, and Gehan-George, but Mosteller is simplest and widely used.

Q4: How accurate is the Mosteller formula?
A: It's accurate to within 1-2% of more complex formulas and is the recommended formula by many medical organizations.

Q5: Can I use pounds and inches?
A: This calculator uses kg and cm. Convert pounds to kg (1 lb = 0.453592 kg) and inches to cm (1 in = 2.54 cm) first.