How is your blood pressure checked?

Blood pressure is usually measured from the upper arm with a device called a sphygmomanometer. An inflatable cuff is wrapped around the bare arm and a stethoscope placed on the inside of the elbow where a pulse can be felt. Pressure is created as the cuff is inflated, causing the blood flow to stop briefly in the arm. As the air is released from the cuff, blood starts to flow again through the artery. The person with the stethoscope listens to the sounds made as the blood flows through the artery.  

What do the readings mean?

Blood pressure consists of two numbers (eg, 130/80) and is measured in millimetres of mercury (mmHg). The first sound recorded as a number is the systolic pressure. This measures the force the heart has to pump against (resistance) to get the blood to flow around the body. The second sound recorded is the diastolic pressure. This measures the resting pressure when the heart relaxes.

Blood pressure changes with environment

Many things can affect your blood pressure. It is normal for your blood pressure to increase during physical activity or when you are excited, angry or afraid, though these rises are usually for short periods.

Some people feel anxious about having their blood pressure recorded in a doctor's office. Anxiety and stress such as this can cause elevated blood pressure known as ‘white coat hypertension’, and further measurements or other types of monitoring may be necessary to establish the usual reading.

Long periods of high blood pressure (hypertension) while at rest will usually need further investigation, monitoring and treatment. Lifestyle measures are very important, both in prevention and management of hypertension. It may also be necessary to take long term medication for hypertension.

See your doctor, nurse or health professional to have your blood pressure checked.

Original material provided by the Heart Foundation of New Zealand, 2005. Reviewed and edited by everybody, February 2011.