Rule of Palms: The surface of the patient's palm is approximately what percent of total body surface area?

• A. 0.5%
• B. 1%
• C. 2%
• D. 5%

Answer: (B)

The main idea is using the patient’s own palm as a quick reference to estimate burn size. The surface area of the palm, including the fingers, is about 1% of the total body surface area. So a burn that covers the size of the palm roughly equals 1% TBSA. This simple rule helps clinicians make fast, first-pass decisions about resuscitation and care in the field when precise measurements aren’t feasible. Larger or smaller estimates aren’t as practical for immediate management: 1% is the established quick approximation. For more accuracy on larger burns or when precise planning is needed, formal charts like Lund and Browder are used.