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What Those Blood Pressure Numbers Mean

A quick, painless test measures blood pressure. A rubber cuff is wrapped around your arm and inflated. The cuff compresses an artery in your arm and momentarily stops your blood flow. A technician uses a stethoscope to measure your blood pressure when the pressure in the cuff is released.

If you are checking your blood pressure at home, here are some tips to help you take an accurate blood pressure:


  • Make sure the blood pressure cuff fits your arm properly. The cuff should be long enough to fit around your arm with several inches extra. It should be wide enough to fit from the inside of the elbow to just below the armpit, according to the American Medical Association (AMA). Measuring the distance from your shoulder to your elbow. If the distance is less than 13 inches, you need a small cuff (5 inches by 9 inches). If the distance is 13 to 16 inches, you need a medium cuff (6 inches by 13 inches). If the distance is more than 16 inches, you need a large cuff (7 inches by 14 inches). An arrow on the cuff helps you align the cuff over an artery.
  • Keep in mind that blood pressure fluctuates during the day and depending on what you are doing. It often is higher in the morning. Your blood pressure also may be higher if you have been talking or if you are under stress.
  • Your blood pressure may be slightly lower at home than when it is measured by your health care provider. Your doctor may ask you to take your blood pressure several times a day.
  • If you smoke or drink caffeinated beverages, these can affect your blood pressure for two or more hours afterward.
  • Talk to your doctor about the type of blood pressure monitor you need. Electronic versions may be convenient, but they are not as accurate as a blood pressure cuff (sphygmomanometer).
Blood-pressure readings are recorded as two numbers. Both are a measurement of the force of the blood against arterial walls. The first, higher number is the systolic pressure, which indicates the pressure of the blood against the arteries when the heart contracts to pump blood. The second, lower number is the diastolic pressure, which indicates the pressure of the blood against the artery walls when the heart is resting in between beats. It indicates the elasticity of the arteries. When blood pressure is recorded, the systolic pressure is always recorded first, followed by a diagonal line and the diastolic pressure.

The higher the number, the harder it is for the heart to pump blood. In a person who has not been diagnosed with high blood pressure or who does not have a chronic illness, a reading above 140/90 indicates hypertension or high blood pressure.

If your blood pressure reading is high, your doctor will take another reading later, to determine if you have high blood pressure. If it is 140/90 mm Hg or higher after two or more readings, your doctor will probably make the diagnosis of high blood pressure, or hypertension.

Here are the numbers to look for when you or someone else is checking your blood pressure. Your doctor may recommend a different schedule for follow-up depending on your risk factors, medical history and current health. Your doctor is your best source of information for your condition.

SYSTOLIC: Less than 130
DIASTOLIC: Less than 85
RECOMMENDED FOLLOW-UP: Have blood pressure checked again in two years

SYSTOLIC:130 to 139
DIASTOLIC: 85 to 89
RECOMMENDED FOLLOW-UP: Have blood pressure checked again in one year

SYSTOLIC:140 to 159
DIASTOLIC: 90 to 99
RECOMMENDED FOLLOW-UP: Have blood pressure checked again within two months

SYSTOLIC:160 to 179
DIASTOLIC: 100 to 109
RECOMMENDED FOLLOW-UP: Have a medical evaluation or seek treatment within one month

SYSTOLIC:180 or higher
DIASTOLIC: 110 or higher
RECOMMENDED FOLLOW-UP: Have a medical evaluation or seek treatment immediately or within one week




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