Where should a lifeguard check for a pulse on an infant?

The brachial pulse is the correct location to check for a pulse on an infant because it is the most accessible site for detecting heartbeat in young children. Infants have smaller, more delicate bodies, making it challenging to locate a pulse in larger areas or those that are not well developed, such as the carotid or radial arteries. The brachial pulse, found on the inside of the upper arm, is typically easier to locate and measure in infants due to its position and the size of the upper arm relative to their anatomical proportions.

In contrast, the carotid pulse is primarily used in adults and may be less reliable for infants, while the radial pulse is situated at the wrist and can be difficult to palpate in very young patients. The femoral pulse, located in the groin area, is also not commonly used for this age group due to the more invasive nature of reaching that area in such small individuals. Thus, checking for the brachial pulse is the established and recommended practice when assessing the pulse of an infant.