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Body Surface Area (BSA)
Calculate your Body Surface Area (BSA) using the Mosteller formula. Essential for determining accurate medical dosages and assessing metabolic rate.
BSA (m²) = √[(height × weight) / 3600]
Understanding Body Surface Area (BSA)
Body Surface Area (BSA) is the measured or calculated surface area of a human body. For many clinical purposes, BSA is a better indicator of metabolic mass than body weight because it is less affected by abnormal adipose mass.
Why is BSA Important?
- Chemotherapy Dosing: Many anti-cancer drugs are dosed according to BSA to maximize efficacy and minimize toxicity.
- Cardiac Index: BSA is used to calculate the Cardiac Index, which relates heart performance to the size of the individual.
- Renal Function: Glomerular Filtration Rate (GFR) is often normalized to a standard BSA of 1.73 m².
⚠️ Clinical Note
While the Mosteller formula used here is widely accepted and easy to use, other formulas (Du Bois, Haycock, Gehan-George) exist. Always follow specific clinical protocols for critical medical dosing.
💡 Expert Tip from Dr. Alex M.
For pediatric patients, BSA is particularly crucial because children have a higher surface area-to-weight ratio than adults. This makes them more susceptible to fluid loss and temperature changes.
Frequently Asked Questions
What is Body Surface Area (BSA)?
Body Surface Area (BSA) is the total surface area of the human body. It is a critical measurement in medicine, used to calculate drug dosages (especially for chemotherapy) and fluid requirements.
Why is BSA used instead of weight?
BSA is considered a more accurate indicator of metabolic mass than body weight alone. It helps minimize the variation in drug distribution and elimination between individuals of different sizes.
What is the normal BSA for an adult?
The average BSA for adult men is approximately 1.9 m², and for adult women, it is approximately 1.6 m². However, this varies significantly with height and weight.