Q1: What is Body Surface Area (BSA) and why is it used?
BSA is the total surface area of the human body, measured in square meters (m²). It's used in medicine to calculate drug dosages, especially for chemotherapy, and to normalize physiological measurements. BSA provides a more accurate dosing method than body weight alone for many medications.
Q2: How is BSA calculated?
This calculator uses the Mosteller formula: BSA (m²) = √[(Height in cm × Weight in kg) / 3600]. This is one of the most commonly used formulas in clinical practice. Other formulas exist (Du Bois, Haycock), but Mosteller is widely accepted and easy to use.
Q3: What is BSA used for in medicine?
BSA is used to calculate: chemotherapy drug dosages, cardiac index, glomerular filtration rate adjustments, burn surface area estimation, and other medical parameters where body size normalization is important. It helps ensure appropriate medication dosing based on body size.
Q4: Is BSA the same as BMI?
No, BSA measures total body surface area (m²), while BMI measures body mass relative to height (kg/m²). BSA is used for medical dosing, while BMI is used for weight classification. They serve different purposes and are calculated differently.
Q5: Why do medical professionals use BSA instead of weight?
BSA correlates better with metabolic processes and organ function than weight alone. Many physiological processes (drug metabolism, cardiac output, kidney function) scale with surface area rather than weight. BSA provides more accurate dosing, especially for medications with narrow therapeutic windows.
Q6: Can I calculate BSA at home?
Yes, you can calculate BSA using online calculators or formulas if you know your height and weight. However, for medical purposes (especially medication dosing), always consult healthcare professionals. They use BSA along with other factors to determine appropriate treatment.