A person's blood pressure is commonly measured with an instrument called a blood pressure cuff or sphygmomanometer. The blood pressure cuff is made up of an air pump, a pressure gauge, and a rubber cuff. The device measures the blood pressure in units called millimeters of mercury.

The procedure for taking blood pressure is as follows. The cuff is placed around the patient's upper arm and inflated with an air pump to a pressure which blocks the flow of blood in the main artery that travels through the person's arm. The arm is extended at the side of the body at heart level. At this time, the pressure from the cuff is slowly released. As the pressure is released, the person doing the procedure, usually a nurse, listens with a stethoscope to the artery at the front of the elbow. The pressure reading at which a pulse is first heard is the systolic pressure. At the point where the pressure finally stops pulsating is the diastolic pressure.

Blood pressure is affected by a number of factors and therefore it is important to standardize the environment when blood pressure is taken. For one hour before taking your blood pressure you should avoid eating, exercise and smoking. These will all affect your blood pressure. There are other stresses that affect blood pressure and should also be avoided.

Most insurance companies consider high blood pressure to be anything above 140/90. However, these may not be appropriate measurements for everybody. As a matter of fact, professionals now believe that there are varying stages of high blood pressure, from a low end to a high end. The range as is now defined is between 120/80 to 139/89. This is called the pre hypertension range and people who fall within this range should think about trying to lower their blood pressure. Usually in pre hypertension cases, simple life style changes are enough to lower the pressure.

For some people, however, a blood pressure reading of 130/80 is perfectly normal especially if they have experienced kidney problems or even kidney disease. The purpose of lowering the pressure in these cases is to reduce the damage done to the kidneys. Patients with diabetes may also benefit from having their blood pressure lowered to 130/80. African Americans may benefit by having their blood pressure lowered to 135/80. The reason that these cases are not lowered to 120/80 is because that is not a realistic goal in their case.

In some cases a person may have isolated systolic or diastolic high blood pressure, meaning that the top or bottom number is elevated while the other number is normal. Examples would be 150/80 or 120/90. In these cases a person is still considered to have high blood pressure and should be treated accordingly.

Patients with borderline high blood pressure may not need immediate treatment but they should keep a careful eye on their blood pressure by having regular checkups.