Final answer:
The recommended site for a capillary stick puncture on an infant is the lateral plantar surface of the heel, as it is less likely to hit bone and is well vascularized for sampling.
Step-by-step explanation:
When performing a capillary stick on an infant, the recommended site for puncture is the infant’s heel, specifically, the lateral plantar surface. This location is preferred because it minimizes the risk of hitting bone, and the area is well supplied with capillaries, making it ideal for capillary blood sampling. It is essential to thoroughly disinfect the site before the procedure and to use an appropriate-sized lancet to make the puncture for the blood sample.