Scian (LD-579)

Blood pressure is a measure of the force of the blood against the wall of a blood vessel. Blood vessels are arteries and veins. They are tubes that carry blood throughout the body. When the heart beats, it pushes blood through these vessels. Blood pressure is a measure of the force on the walls of an artery when the heart beats and when it relaxes between beats.

• Blood pressure is written as 2 numbers, for example, 110/60.
• The systolic blood pressure (suh-staa-luhk), the top number, is the pressure of the blood against the artery walls when the heart beats.
• The diastolic blood pressure (dai-uh-staa-luhk), the bottom number, is the pressure of the blood against the artery walls between heartbeats.
• Blood pressure can change during the day. It is often the lowest in the morning. Things that can affect blood pressure are:  emotions, age, medicines, activity, body size, very hot or cold air temperature, and illness, injury, or pain.
• A normal BP for one child may not be normal for another. For children under age 18 years, a normal BP is based on their height. The doctor or health care provider will tell you what is normal for your child.