With mercury blood pressure monitors being gradually phased out, the traditional sphygmomanometer is finding itself increasingly replaced by more technologically savvy machines. Even though blood pressure monitors now come in many different digital and electronic models, making blood pressure easier to check, the manual method is still credited with taking a more accurate pressure. Although some people prefer to use newer instruments that self inflate and automatically release pressure, many health care professionals continue to take blood pressure readings manually. But it does take practice to get the procedure down right.
Things You'll Need
- Blood pressure cuff and gauge
Ask the person to sit in an upright position with her left arm stretched out, palm upward and arm bent just a little at the elbow. The upper arm should be positioned at the same level as the heart. The person may be more comfortable if the arm is supported by an armrest or resting on a table. Feet should be flat on the floor.
Make sure the person is calm and relaxed before beginning. If you are monitoring someone’s blood pressure on a regular basis, take it at the same time every day in the same arm. Keep in mind that a person’s blood pressure can be different in each arm, sometimes by as much as 20 millimeters. Blood pressure also tends to be higher during the morning hours and lower in the evening.
Close the air release valve on the sphygmomanometer by turning it clockwise. With sleeve rolled up, wrap the inflatable blood pressure cuff around the person’s upper arm. The cuff should be snug and fitted evenly, with the bottom edge 1/2-inch above the elbow. There should be no twists in the attached rubber tubing.
Locate the pulse by pressing the index and middle fingers of your other hand to the inside of the arm just above the person’s elbow crease. With the earpieces of the stethoscope in your ears, place the bell of the stethoscope on the skin below the cuff. The chest piece of the stethoscope should be right over the brachial artery where the pulse is strongest.
Begin pumping the hollow rubber bulb attached to the blood pressure cuff until you hear no sounds coming through the stethoscope. Inflate the cuff by squeezing and releasing the air bulb rapidly. Once the cuff is tight enough, blood flow in the artery will stop. The gauge should read 30 to 40 millimeters more than the person’s usual systolic pressure. If the person’s normal blood pressure is unknown, inflate the cuff to 180 millimeters, but do not inflate the arm cuff more than necessary.
Turn the air release valve slowly in a counterclockwise direction to deflate the cuff and release the pressure. Pressure should begin to fall at about 2 or 3 millimeters per second.
Listen closely for the first sounds as blood begins to flow through the artery again. The sounds may resemble a tapping noise at first. Watch the reading on the gauge. This is the person’s systolic pressure. As the pressure in the cuff continues to drop, the sounds you hear will begin to fade until they finally stop. Check the gauge for the diastolic pressure reading. Let out any air remaining in the cuff.
Take the person’s blood pressure another time or two for accuracy. Wait approximately five minutes each time. Some people may need to wait a few minutes longer between readings until blood flow in the arm returns to normal.