What method is preferred for determining heart rate in an infant?

The preferred method for determining heart rate in an infant is by assessing the apical pulse. The apical pulse is measured at the apex of the heart, typically located just below the left breast, where the heart's sounds are most audible. Using a stethoscope to listen directly to the heart beats allows for an accurate measurement of heart rate, which is especially important in infants due to their rapid and variable heart rates.

In infants, peripheral pulses can be more difficult to palpate accurately because of their small size and the generally weaker circulation. The radial and carotid pulses can be challenging to assess in infants, and relying on them may lead to inaccurate readings. The femoral pulse is also less commonly used for routine heart rate measurement due to its location and accessibility challenges. Therefore, taking the apical pulse is the most reliable method in this population.