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. For amputees, adjustments are needed to account for the missing body parts.

2. How Does the Calculator Work?

The calculator uses the Mosteller formula with amputation adjustment:

Where:

• \( W \) — Weight in kilograms (kg)
• \( H \) — Height in centimeters (cm)
• \( \text{Adjustment factor} \) — Percentage of body surface lost (as decimal)

Explanation: The standard Mosteller formula is adjusted by subtracting the percentage of body surface area lost to amputation.

3. Importance of BSA Calculation

Details: Accurate BSA calculation is crucial for proper drug dosing (especially chemotherapy), determining appropriate fluid resuscitation volumes, and calculating various physiological measurements.

4. Using the Calculator

Tips: Enter weight in kg, height in cm, and select the appropriate adjustment factor based on amputation type. All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: Why adjust BSA for amputations?
A: Amputations reduce total body surface area, which affects drug distribution and dosing requirements.

Q2: What are typical BSA values?
A: Average BSA is about 1.7 m² for adult men and 1.6 m² for adult women, but varies with body size.

Q3: How accurate are these adjustments?
A: Adjustment factors are estimates based on standard percentages of body surface area for each limb segment.

Q4: What about multiple amputations?
A: For multiple amputations, add the adjustment factors (but don't exceed 100% total adjustment).

Q5: Are there other BSA formulas?
A: Yes, other formulas include Du Bois and Haycock, but Mosteller is most commonly used due to its simplicity and accuracy.