Mostellar Equation Calculator

Enter Height (cm):
Enter Weight (kg):
Calculate
Result (Body Surface Area BSA in m²):

The Mostellar equation is a widely used formula in medicine to estimate a person’s body surface area (BSA), which is a critical measurement for determining dosages of certain medications and assessing overall body metabolism. The equation is simple and relies on a person’s height and weight to calculate BSA, often used for adjusting drug doses in chemotherapy and other treatments.

Formula

The Mostellar equation for calculating body surface area is:

BSA = Square Root of (Height in cm * Weight in kg / 3600)

Where:

• Height (H) is measured in centimeters.
• Weight (W) is measured in kilograms.
• The result is given in square meters (m²).

How to Use

1. Enter Height (H): Provide the height in centimeters (cm).
2. Input Weight (W): Provide the weight in kilograms (kg).
3. Click the “Calculate” button to calculate the body surface area (BSA) using the Mostellar formula.
4. The result will be displayed in square meters (m²), which is the standard unit for BSA.

Example

Let’s say an individual has a height of 170 cm and weighs 70 kg. Using the Mostellar equation:

BSA = Square Root of (170 * 70 / 3600) ≈ 1.84 m²

This means that the body surface area of this individual is approximately 1.84 square meters.

FAQs

1. What is the Mostellar equation used for?
   The Mostellar equation is used to estimate body surface area (BSA) based on a person’s height and weight.
2. Why is body surface area important in medicine?
   BSA is used to calculate appropriate drug dosages, particularly in chemotherapy, as well as to evaluate metabolic rates and cardiac output.
3. Can the Mostellar equation be used for children?
   Yes, the Mostellar equation can be used for both children and adults, but there are alternative formulas specifically designed for pediatric patients.
4. Is BSA measured directly?
   No, BSA is not measured directly. Instead, it is estimated using formulas like the Mostellar equation, which relies on height and weight.
5. What unit of measurement is BSA?
   BSA is typically expressed in square meters (m²).
6. How accurate is the Mostellar equation?
   The Mostellar equation is one of the most accurate and commonly used formulas for estimating BSA, but like all estimation methods, it has its limitations.
7. What is a normal BSA value?
   The average BSA for adults is around 1.7 to 2.0 m², although it varies depending on a person’s size.
8. Why is the number 3600 used in the formula?
   The constant 3600 in the Mostellar equation normalizes the height and weight values to produce an output in square meters.
9. Can BSA be used to calculate drug doses?
   Yes, BSA is a crucial parameter for calculating drug dosages, especially in treatments like chemotherapy, to ensure safe and effective dosing.
10. How does BSA differ from BMI?
    BSA estimates the total surface area of the body, whereas BMI (Body Mass Index) measures body fat based on height and weight.
11. Does weight loss or gain affect BSA?
    Yes, significant weight changes will affect BSA since the formula incorporates both height and weight.
12. Can the Mostellar equation be used for obese patients?
    While the Mostellar equation works for a wide range of patients, other BSA formulas may be more accurate for individuals with extreme obesity.
13. Is the Mostellar equation used globally?
    Yes, the Mostellar equation is used by healthcare professionals worldwide due to its simplicity and accuracy.
14. What are some other BSA calculation methods?
    Other common methods include the DuBois and DuBois formula and the Haycock formula, which are alternatives to Mostellar.
15. Is BSA used in determining metabolic rate?
    Yes, BSA is often used in calculating metabolic rate because it represents the total area of skin surface, which is related to heat loss and metabolism.
16. Can the Mostellar equation be used in veterinary medicine?
    While the Mostellar equation is designed for humans, veterinary medicine uses similar BSA-based formulas for animals.
17. Is BSA related to organ function?
    Yes, BSA can be an indicator of organ function, particularly in assessing kidney function and drug clearance rates.
18. How often should BSA be recalculated?
    BSA should be recalculated whenever there are significant changes in weight or height, such as during weight loss, growth in children, or illness.
19. How does BSA impact chemotherapy dosing?
    Chemotherapy doses are often adjusted based on BSA to ensure that patients receive the most effective and safest amount of the drug.
20. Are there calculators available for BSA?
    Yes, many online calculators and tools, like the Mostellar equation calculator, are available to estimate BSA quickly and accurately.

Conclusion

The Mostellar Equation Calculator is a simple and effective tool for determining body surface area (BSA) based on height and weight. BSA plays a significant role in medical practices, especially in calculating dosages for treatments like chemotherapy and assessing metabolic functions. By applying the formula BSA = SQRT(H * W / 3600), healthcare professionals can make critical decisions regarding patient care.