1. What is Body Surface Area (BSA)?

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. BSA is considered a more accurate indicator of metabolic mass than body weight.

2. How Does the Calculator Work?

The calculator uses one of three common formulas to estimate BSA:

Where:

• \( H \) — Height in centimeters
• \( W \) — Weight in kilograms

Explanation: Each formula provides slightly different estimates of body surface area based on height and weight measurements.

3. Importance of BSA Calculation

Details: BSA is used in many medical contexts including chemotherapy dosing, cardiac index calculations, and renal function assessment. It helps standardize physiological measurements across individuals of different sizes.

4. Using the Calculator

Tips: Enter height in centimeters, weight in kilograms, and select your preferred formula. The Mosteller formula is simplest and most commonly used in clinical practice.

5. Frequently Asked Questions (FAQ)

Q1: Which BSA formula is most accurate?
A: The DuBois formula was derived from direct measurements but all formulas have similar accuracy for most clinical purposes.

Q2: What are typical BSA values?
A: Average BSA is about 1.7 m² for adult men and 1.6 m² for adult women. Normal range is approximately 1.5-2.0 m².

Q3: Why use BSA instead of weight for drug dosing?
A: Many physiological processes correlate better with surface area than weight, especially for drugs with narrow therapeutic windows.

Q4: How does BSA change with age?
A: BSA increases with growth in children, peaks in young adulthood, and may decrease slightly with aging due to height loss and muscle loss.

Q5: Are there limitations to BSA calculations?
A: These formulas may be less accurate for extremely obese or muscular individuals, and for certain ethnic populations.