China's new nine-point method divides the body surface area into 1 1 9% and adds 1% of perineum to form the total surface area 100%, namely:
Head and neck = 9% × 1-3% for hair, face and neck;
Trunk = 3× 9%- anterior trunk 13%, posterior trunk 13%, perineum1%;
Double upper arms = 2×9%- double upper arms 7%, double forearms 6%, hands 5%;
Lower limb = 5×9%- hip 5%, thigh 2 1%, calf 13%, foot 7%; (Adult women have 6% hips and 6% feet)
Memory formula: 333567 133 perineum 15732 1.
It should be noted that children have large heads and small lower limbs, which can be calculated as follows: the area of head and neck is 9+( 12- age)%, and the area of both lower limbs is 46-( 12- age) %(46% is the area ratio of adult males' lower limbs).
Regardless of age and sex, the palm of the patient's finger accounts for about 1% of the body surface area. If the size of the doctor's palm is similar to that of the patient, it can be estimated by the doctor's palm.