Using the adult Rule of Nines, what percentage of the total body surface area has been burned in a patient with burns to the head, anterior chest, and both anterior upper extremities?

• A. 45%
• B. 18%
• C. 36%
• D. 27%

Answer: (D)

Using the adult Rule of Nines, total body burn area is found by adding the percentages for each burned region. The head accounts for 9% of TBSA. The anterior chest is 9% as it is part of the 18% anterior trunk (the chest makes up one half of that anterior section). The anterior surface of both upper extremities together equals 9% (4.5% per arm, since each arm is 9% total for the whole limb, split between front and back). So you add 9% + 9% + 9% to get 27% TBSA burned.