Hypertension/High Blood Pressure Health Center

How It Is Done continued...

Close the valve on the rubber inflating bulb. Squeeze the bulb rapidly with your opposite hand to inflate the cuff until the dial or column of mercury reads about 30 mm Hg higher than your usual systolic pressure. (If you don't know your usual pressure, inflate the cuff to 210 mm Hg or until the pulse at your wrist disappears.) The pressure in the cuff will stop all blood flow within the artery temporarily.

Now open the pressure valve just slightly by twisting or pressing the valve on the bulb. The pressure should fall slowly at about 2 to 3 mm Hg per second. Some blood pressure devices have a valve that automatically controls this rate. As you watch the pressure slowly fall, note the level on the dial at which you first start to hear a pulsing or tapping sound through the stethoscope. The sound is caused by the blood starting to move through the closed artery. This is your systolic blood pressure. If you have trouble hearing the start of your pulse through the stethoscope, you can check your systolic blood pressure by noting the level on the dial when you are able to feel the pulse at your wrist once again.

Continue letting the air out slowly. The sounds will become muffled and will finally disappear. Note the pressure when the sounds completely disappear. This is your diastolic blood pressure. Finally, let out all the remaining air to relieve the pressure on your arm.

Be sure to write your numbers in your log book, along with the date and time.

Electronic blood pressure monitors

Sit with your arm slightly bent and resting comfortably on a table so that your upper arm is on the same level as your heart. Expose your upper arm by rolling up your sleeve but not so tightly as to constrict blood flow. If you are not able to roll up your sleeve, remove your arm from the sleeve or take off your shirt. Wrap the blood pressure cuff snugly around your upper arm so that the lower edge of the cuff is about 1 in. (2.5 cm) above the bend of your elbow.

For electronic models, press the on/off button on the electronic monitor and wait until the ready-to-measure "heart" symbol appears next to zero in the display window. Then press the start button. The cuff will inflate automatically to approximately 180 mm Hg (unless the monitor determines that you require a higher value). It then begins to deflate automatically, and the numbers on the screen will begin to drop. When the measurement is complete, the heart symbol stops flashing and your blood pressure and pulse readings are displayed alternately.

All blood pressure monitors

At first it is a good idea to take your blood pressure 3 times in a row, 5 or 10 minutes apart. As you get more comfortable taking your own blood pressure, you will only need to measure it once or twice each time.

Check your blood pressure cuff frequently to see that the rubber tubing, bulb, valves, and cuff are in good condition. Even a small hole or crack in the tubing can lead to inaccurate results.

To help develop your skills, see:

High Blood Pressure: Checking Your Blood Pressure at Home.