Question: Encounter notes indicate that an adult patient suffered burns to their right arm and anterior chest and abdomen. What would be the total body surface area (TBSA) for this patient’s burns? Illinois Subscriber Answer: If you are using the rule of nines, then you’ll add 18 percent for the anterior chest and 9 percent for the right arm for a total TBSA of 27 percent. If you use the Lund-Browder method, then you’ll add 13 percent for the anterior chest and 8 percent for the right arm for a total TBSA of 21 percent.