Blood pressure is an important indicator of health. Knowing one's blood pressure is the first step to preventing heart disease. Though most physicians take blood pressure using an automatic blood pressure monitor, knowing how to use a manual blood pressure monitor is an important skill for anyone interested in health. If you or someone you know is at risk for high or low blood pressure, it may be beneficial to invest in a blood pressure monitor for home use.
- Blood pressure cuff
- attached pump
- test subject
The cost of an inexpensive manual blood pressure monitor is $16.99 at the local drug store.
5 minutes or less
Do not keep blood pressure cuff inflated for long periods of time as this will limit blood circulation to the cuffed arm.
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Step 1: Preparation
- When taking someone else's blood pressure, have them sit in a chair with their legs uncrossed and feet resting on the ground.
- If your partner has long sleeves, have them roll up their sleeves so that their upper left arm is bare.
- Have your partner relax, and place one arm, palm up, on their lap.
Step 2: Feel for Brachial Artery Pulse
- Press down firmly with two fingers on the inside of your partner’s elbow to feel for a pulse.
- Pulse should be located near the inside of the inner elbow.
- If the pulse is difficult to locate, move fingers around the inner elbow until you find the pulse.
Step 3: Wrap Cuff Around Partner's Arm
- Tuck the end of the cuff through the metal loop and slide onto your partner’s arm. Using the Velcro on the cuff, secure the cuff roughly one half inch above the bend of the elbow.
- The cuff will have a line or arrow marked on it so that it can be properly placed around the arm.
- Make sure the line or arrow lines up with the brachial artery in the inner elbow. The pulse felt in step one gives the general position of the brachial artery.
- The cuff should fit snugly so that the skin is not pinched.
- It should be possible to fit two fingertips under the cuff, but not the entirety of the fingers.
Step 4: Position Gaugue So It Is Visible
- If the gauge on the cuff is not visible when viewing from above, move it so that the face is easily seen.
Step 5: Place Stethoscope Underneath Cuff
- Place the flat, drum-like part of the stethoscope underneath the cuff on top of your partner’s brachial artery.
- Put the ear tips of the stethoscope into your ear.
- Lightly hold the stethoscope in place with one hand.
Step 6: Inflate the Cuff Using Pump Bulb
- Hold the stethoscope in place with one hand and the pump with the other.
- Turn the screw of the pump bulb clockwise several times to close the airflow valve.
- Squeeze the bulb rapidly while watching the dial on the gauge increase to indicate the pressure.
- Keep squeezing until the gauge reads between 160 and 180 mmHg.
- If the dial moves but then falls, make sure the airflow valve is closed. Turn the screw on the pump bulb clockwise several more times and retry.
Step 7: Deflate the Cuff Slowly
- Slowly turn the screw on the pump bulb counterclockwise to open the airflow valve.
- The dial on the gauge should fall at about 2 mmHg (millimeters of mercury) per second.
- If the dial falls too fast so that a measurement cannot be taken, release all of the air in the cuff and start over from step 5.
Step 8: Listen for the Systolic Pressure
- At around 120 mmHg, your partner’s pulse should become audible.
- Record the pressure reading at the exact moment the pulse becomes audible. This is the systolic pressure reading.
Step 9: Listen for the Diastolic Pressure
- At around 80 mmHg, your partner’s pulse will fade.
- Record the pressure reading when the pulse is no longer audible. This is the diastolic pressure reading.
- Once you have a diastolic reading, turn the screw on the pump bulb counterclockwise to open the airflow valve and quickly release the rest of the air in the cuff.
- If you failed to note the systolic or diastolic pressure, restart from step 5.
Step 10: Interpret the Results
- Blood pressure is typically recorded as two numbers, written as a ratio like this: 120/80 mmHg (read 120 over 80 millimeters of mercury).
- Systolic blood pressure goes on top of the ratio and refers to the force blood exerts against the artery walls as the heart pumps.
- Diastolic blood pressure goes on bottom of the ratio and refers to the blood pressure between heartbeats.
- The average blood pressure of a healthy adult should be around 120/80 mmHg.
- If a person’s blood pressure is consistently higher than 140/90 mmHg it could be a sign of hypertension.