Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps blood. High blood pressure, sometimes called hypertension, happens when this force is too high. Healthcare workers check blood pressure readings the same way for children, teens and adults. They use a gauge, stethoscope or electronic sensor, and a blood-pressure cuff.
With this equipment, they measure:
■ Systolic pressure: blood pressure when the heart beats while pumping blood
■ Diastolic pressure: blood pressure when the heart is at rest between beats
Healthcare workers write blood-pressure numbers with the systolic number above the diastolic number.
For example: 118/76 mmHg
People read this as “118 over 76” millimeters of mercury.
Normal blood pressure for adults is defined as a systolic pressure below 120 mmHg and a diastolic pressure below 80 mmHg. It is normal for blood pressures to change when you sleep, wake up, or are excited or nervous. When you are active, it is normal for your blood pressure to increase. However, once the activity stops, your blood pressure returns to your normal baseline range. Blood pressure normally rises with age and body size. If your blood pressure is higher than normal when at rest, you may want to talk with your doctor about what you can do to bring it back to the normal range.
— Source: National Heart, Lung, and Blood Institute