Body Surface Area Calculator NHS

Mosteller Formula:

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

BSA (m²):

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1. What is Body Surface Area (BSA)?

Definition: BSA is a calculated measurement of the total surface area of the human body, often used in medical practice.

Purpose: It's used to calculate medical dosages, assess metabolic mass, and determine treatment parameters.

2. How Does the Calculator Work?

The calculator uses the Mosteller formula recommended by the NHS:

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

Where:

\( BSA \) — Body surface area (square meters)
\( W \) — Weight (kilograms)
\( H \) — Height (centimeters)

Explanation: The product of weight and height is divided by 3600, then the square root is taken to obtain BSA in m².

3. Importance of BSA Calculation

Details: BSA provides a more accurate measurement than body weight alone for determining medication dosages, chemotherapy drugs, and other medical treatments.

4. Using the Calculator

Tips: Enter weight in kilograms and height in centimeters. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is BSA used instead of weight alone?
A: BSA correlates better with metabolic processes and drug distribution than body weight alone.

Q2: What's the average BSA for adults?
A: 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, including DuBois and Haycock formulas, but Mosteller is simplest and NHS-recommended.

Q4: How accurate is this calculation?
A: It's clinically validated and within 1-2% of more complex formulas.

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