New York State Basic Emergency Medical Technician (EMT-B) Practice Exam

If an adult suffers partial thickness burns over the chest, abdomen, back, buttocks, and right arm, what percentage of body surface has been burned according to the rule of 9's?

1. 36%

2. 45%

3. 54%

4. 27%

The correct answer is: 45%

To determine the percentage of body surface area burned using the rule of nines, it is important to understand how this system distributes body surface area percentages among adults. According to this method, the body is divided into sections, each representing approximately 9% (or a multiple thereof) of the total body surface area. In adults, the breakdown is as follows: - The head and neck = 9% - Each arm = 9% - Each leg = 18% - The anterior trunk (chest and abdomen) = 18% - The posterior trunk (back) = 18% - The perineum = 1% For the scenario provided, we're dealing with burns over the following areas: - Chest and abdomen (anterior trunk) = 18% - Back (posterior trunk) = 18% - Buttocks (part of the posterior trunk) = approximately 9% - Right arm = 9% Adding these percentages together gives: 18% (anterior trunk) + 18% (posterior trunk) + 9% (buttocks) + 9% (right arm) = 54%. While the buttocks is sometimes treated differently in clinical settings, considering it in this calculation leads