1. What is Body Surface Area?

Body Surface Area (BSA) is the measured or calculated surface area of the human body. It's an important measurement in medicine, particularly for calculating drug dosages and medical indicators.

2. Mosteller Formula Explained

The NHS-recommended Mosteller formula:

Where:

• \( W \) — Weight in kilograms (kg)
• \( H \) — Height in centimeters (cm)
• \( BSA \) — Body surface area in square meters (m²)

Explanation: The Mosteller formula provides a simple yet accurate way to estimate body surface area from weight and height measurements.

3. Clinical Importance of BSA

Details: BSA is used to calculate drug dosages for chemotherapy, assess cardiac index, and determine appropriate fluid resuscitation volumes. It's more accurate than body weight alone for many medical calculations.

4. Using the Calculator

Tips: Enter weight in kilograms and height in centimeters. For best results, use precise measurements. The calculator will compute BSA using the Mosteller formula.

5. Frequently Asked Questions (FAQ)

Q1: Why use Mosteller formula instead of others?
A: The Mosteller formula is simple, validated, and recommended by NHS as it provides accurate results comparable to more complex formulas.

Q2: What is a normal BSA range?
A: Average BSA is about 1.7 m² for adult men and 1.6 m² for adult women, but varies significantly with body size.

Q3: When is BSA used in medicine?
A: Commonly used for chemotherapy dosing, pediatric drug calculations, burn assessment (rule of nines), and cardiac output measurements.

Q4: Are there limitations to BSA calculations?
A: Formulas may be less accurate for extreme body types (very obese or very thin individuals) and children.

Q5: Should BSA be used for all drug dosing?
A: No, only for specific drugs where BSA-based dosing is clinically validated (e.g., chemotherapy). Many drugs use weight-based or fixed dosing.