Blood Pressure Readings & What They Mean

Because most people are unable to sense their own blood pressure and there can be no symptoms when it's abnormal, the National Institute of Health recommends a yearly blood pressure check for adults ages 18 and over. The test is noninvasive, is performed while patients sit down with one sleeve rolled up and takes little time.

What is Blood Pressure?

• As the heart pumps blood through the body, a force is exerted on each of the arteries that carries it to various organs. This force is measured by blood pressure, which is determined by the size and flexibility of the arteries as well as by the amount of blood the heart is required to pump. The exact number always changes due to factors like diet, medication, emotional or physical states, temperature, posture and exercise.

Blood Pressure Test

• Most people are familiar with taking blood pressure tests. They can be taken at any time and don't require any preparation from patients. Patients should wait until they are calm, especially if trips to the doctor's office make them skittish. Instruments needed for the test consist of a cuff with measurement dials placed above the elbow and a stethoscope to measure the results. Health practitioners find a large artery in the arm and place the stethoscope on that location. Next, they fill up the cuff with air, generally to 210 mmGh, or millimeters of mercury, the standard unit used to measure blood pressure. When that point is reached, the air is let out. The test can be preformed two or more times in one session, and the only side effects may be temporary numbness or a tingling sensation in the arm.

Getting the Reading

• When the valve on the cuff is opened and the air starts flowing out, practitioners record the first pulsing sound they hear and the numerical value associated with it. This is called systolic pressure, the highest amount of exertion on the arteries when the heart contracts. As the deflation continues, they monitor the last pulsing sound made and they record it. This is the diastolic pressure, the lowest amount of pressure on the arteries when the heart relaxes. These numbers together form the blood pressure reading, which is expressed as the systolic value over the diastolic value.

What the Result Means

• In general, the benchmark for systolic blood pressure readings is 120 mmHg, and the benchmark for diastolic readings is 80 mmHg. Lower numbers are considered healthy. Pre-high blood pressure exists when the systolic reading is at 120 mmHg to 139 mmHg and the diastolic at 80 mmHg to 89 mmHg. Mild high blood pressure can be diagnosed with the systolic reads 140 mmHg to 159 mmHg and the diastolic reads 90 mmHg to 99 mmHg. When systolic pressure is recorded at anything over 160 mmHg and the diastolic at anything over 100 mmHg, blood pressure is considered moderately or severely high. Alternatively, some people have blood pressure that is too low. That condition is categorized by systolic pressures lower than 90 mmHg or 25 mmHg lower than normal.

Abnormal Readings and Risk

• High blood pressure is associated with diseases including heart failure, kidney disease, heart attack and stroke, and increases the risks of developing one or more of them. Low blood pressure could also be signs of trouble, as it's connected to heart failure, dehydration, gland disorders and infection. Those experiencing high or low blood pressure readings should consult their doctor.