Blood pressure testing is part of nearly every visit to the doctor’s office and hospital. Testing is performed to identify high blood pressure, which is dangerous to the heart and many internal organs. The National Heart Lung and Blood Institute notes the risk of heart disease increases in individuals with high blood pressure.
Definition
Blood pressure readings are made up of two numbers, one over the other, such as 120/80. The top number is known as the systolic blood pressure. The systolic pressure indicates the amount of pressure exerted when the heart contracts, or beats. The bottom number is known as the diastolic pressure, measuring the pressure when the heart relaxes between beats, according to HealthSquare.com.
Measurement
Blood pressure can be measured using a digital blood pressure monitor, or a standard cuff and stethoscope. With a digital monitor, the cuff is placed on the upper arm beginning one inch above the elbow.
Although digital monitors vary in features and function, most simply require that the user press the start button. The machine automatically inflates and deflates the cuff, then displays the blood pressure on the screen.
Blood pressure may also be measured using a blood pressure cuff and stethoscope. With this method, the cuff is inflated and a stethoscope is used to listen as blood flows through the brachial artery in the arm. The systolic blood pressure is determined when the heartbeat is first heard as the cuff deflates. The diastolic blood pressure is determined when the heartbeat is last heard.
Ranges
Blood pressure readings help determine the health of the body’s circulatory system. MayoClinic.com explains that a blood pressure reading of less than 120/80 indicates a normal, healthy blood pressure reading. Prehypertension is indicated by a systolic reading of 120 to 139 or a diastolic reading of 80 to 89. Stage one hypertension has a systolic reading of 140 to 159 or a diastolic reading of 90 to 99. Stage two hypertension is a systolic reading of 160 or greater, or a diastolic reading of 100 or greater.
Considerations
Many factors can cause variations in blood pressure readings. Health Square notes that the time of day or stress can cause fluctuations in blood pressure. A patient’s position and movement can also affect blood pressure readings. For accuracy, patients should sit still, with feet placed flat on the floor and back supported after resting for at least five minutes.
Warning
To be considered accurate, blood pressure readings must be taken with a properly sized cuff for each individual patient. Wellsource explains that an arm circumference of 9 to 13 inches requires a standard sized cuff but a circumference of 13 to 17 inches requires a large cuff. If the cuff is improperly sized, a false reading can occur.
