West Coast EMT Block One Exam

Why does an infant's blood pressure typically increase with age?

1. His or her normal heart rate usually increases with age.

2. The infant's total blood volume decreases with age.

3. As the infant gets older, his or her blood vessels dilate.

4. Blood pressure directly corresponds to body weight.

The correct answer is: Blood pressure directly corresponds to body weight.

Blood pressure is influenced by various factors, one of which is body weight. As an infant grows, their body weight increases, leading to a corresponding rise in blood pressure. This is due to the fact that as the body grows, the heart needs to pump harder to circulate blood throughout a larger body. An increase in body weight generally requires an increase in blood pressure to ensure adequate perfusion to all organs and tissues. As infants age, both body surface area and blood volume increase, which also contributes to the need for higher blood pressure to maintain efficient circulation. The physiology of the cardiovascular system adapts with growth, supporting the increased demand that comes with body weight gain. This understanding highlights the relationship between growth, body weight, and blood pressure in developing infants.