1. What is Body Surface Area (BSA) Calculator for Amputees?

Definition: This calculator estimates the body surface area of amputees by adjusting the standard BSA calculation with an amputation factor.

Purpose: It helps medical professionals determine accurate medication dosages, nutritional needs, and burn assessment for patients with limb amputations.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( BSA \) — Body Surface Area (square meters)
• \( W \) — Weight (kilograms)
• \( H \) — Height (centimeters)
• \( A \) — Adjustment factor for amputation (decimal)

Explanation: The standard Mosteller formula is adjusted by subtracting the proportional body surface area of the amputated limb(s).

3. Importance of Adjusted BSA Calculation

Details: Accurate BSA is crucial for proper drug dosing (especially chemotherapy), fluid resuscitation, and nutritional support in amputee patients.

4. Using the Calculator

Tips: Enter the patient's current weight in kg, height in cm, and appropriate adjustment factor (see table below). All values must be > 0 (adjustment 0-1).

5. Amputation Adjustment Factors

Common Adjustment Values:

• Hand: 0.03
• Below elbow: 0.06
• Above elbow: 0.08
• Foot: 0.05
• Below knee: 0.12
• Above knee: 0.16
• Multiple amputations: Sum of individual factors

6. Frequently Asked Questions (FAQ)

Q1: Why adjust BSA for amputees?
A: Standard BSA formulas overestimate actual body surface in amputees, potentially leading to medication overdosing.

Q2: How is the adjustment factor determined?
A: Factors are based on the proportion of total body surface area represented by each limb segment.

Q3: Should I use current weight or pre-amputation weight?
A: Always use the patient's current weight for most accurate calculations.

Q4: What about bilateral amputations?
A: Double the adjustment factor (e.g., bilateral below-knee = 0.24).

Q5: Are there other BSA formulas?
A: Yes, but Mosteller is most common. This adjustment method works with any BSA formula.