1. What is the Haycock BSA Formula?

The Haycock formula is one of several methods to estimate body surface area (BSA) from height and weight. It's particularly accurate across different age groups and is commonly used for medication dosing calculations.

2. How Does the Calculator Work?

The calculator uses the Haycock BSA formula:

Where:

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

Explanation: The formula accounts for the non-linear relationship between body dimensions and surface area, providing a more accurate estimate than simple linear models.

3. Importance of BSA Calculation

Details: BSA is crucial for determining proper medication dosages, especially for chemotherapy drugs, calculating cardiac index, and assessing metabolic rate. Many medications are dosed per m² of body surface area.

4. Using the Calculator

Tips: Enter weight in kilograms and height in centimeters. For best accuracy, measure height without shoes and weight with minimal clothing.

5. Frequently Asked Questions (FAQ)

Q1: Why use Haycock instead of other BSA formulas?
A: The Haycock formula has been shown to be more accurate across different age groups and body sizes compared to older formulas like DuBois.

Q2: What are typical BSA values?
A: Average BSA is about 1.7 m² for adult men and 1.6 m² for adult women. Neonates have about 0.25 m².

Q3: When should BSA be used for dosing?
A: BSA-based dosing is common for chemotherapy, some antibiotics, and other drugs with narrow therapeutic windows.

Q4: Are there limitations to BSA calculations?
A: BSA formulas may be less accurate in extremely obese or cachectic patients, and some drugs may require alternative dosing methods in these populations.

Q5: Can I use pounds and inches?
A: The formula requires metric units (kg and cm). Convert pounds to kg (1 lb = 0.453592 kg) and inches to cm (1 in = 2.54 cm) first.