David Gould/Photographer's Choice RF/Getty Images. Having your blood pressure (BP) measured is a routine part of visiting your doctor. Ho
Having your blood pressure (BP) measured is a routine part of visiting your doctor. However, it's also easy to measure your BP at home. The good news is that home BP readings, when done properly, are a more accurate predictor of cardiovascular risk than BP readings measured in the medical office.
You should consider measuring your BP at home if:
- You have a known high BP problem (hypertension). Home BP measurements will help determine if your treatment is effective.
- You or your doctor suspect that you may have white coat hypertension, defined as high BP in the medical office, but normal BP at home
- You or your doctor suspect that you may have masked hypertension, defined as normal BP in the medical office, but high BP at home
BP monitors for home use come in many different styles. In general, the American Heart Association recommends that you use an automatic BP monitor with a cuff that fits around your upper arm.
Automatic vs Manual
The traditional, manual method of measuring BP requires you to inflate the cuff by squeezing a bulb and listen to how the pulse changes as the cuff deflates. This is a technical and complex skill. Fortunately, automatic BP monitors make the task much easier. At the push of a button, the cuff will inflate and measure your BP as it slowly deflates.
Note: Measuring BP with an automatic machine may not be accurate if you have atrial fibrillation.
Ask your doctor for advice in this situation.
Location of BP Cuff
The most accurate and reliable way to measure BP is to use a cuff that goes around your upper arm, or bicep area, above the elbow. It may be convenient to use a machine that measures BP at your wrist or finger because you don’t have to roll up your sleeve.
However, BP readings with these machines are particularly sensitive to the position of your wrist and finger. And the smaller arteries in your wrist and finger (compared to your upper arm) also make the BP readings less accurate. Therefore, wrist and finger monitors are not recommended unless no other alternative is available.
Size of BP Cuff
Make sure the cuff fits properly. If the cuff is too small (too tight around your arm), the BP measurement will be falsely elevated. If the cuff is too large (too loose), the BP measurement will be falsely low. Usually the BP monitor will come with instructions to determine if the cuff is the correct size for you.
Record and Send BP Readings
Most BP cuffs with a digital display will record several weeks of your BP readings. Make sure that you don't lose these readings as the memory clears. Write them down or plug the monitor into your computer or smartphone. If the service is available, send your BP readings directly to your health care provider.
Consult this rating of upper arm BP monitors and choose one that is specifically recommended.
Your body position affects your blood pressure. no matter which type of monitor you are using.
There are key points to remember before and during BP measurement.
Before you measure your BP:
- Don't smoke, drink caffeinated or alcholic beverages, or exercise within 30 minutes before measuring your BP
- Empty your bladder
- Rest quietly for 5 minutes before measuring BP
When measuring your blood pressure:
- Sit in a chair with your back supported and feet flat on the ground
- Do not cross your legs or ankles
- Support your arm on a table so that your upper arm (bicep) is even with your heart. Don’t let your arm dangle at your side and don’t raise it too high.
- Turn your palm facing up
- Place the BP cuff around your bare upper arm, one inch above the crease of your elbow
- Press the start button on the monitor. The cuff will automatically inflate and read your BP as it deflates.
- Take two or three readings, one minute apart
It's also a good idea to check your BP monitor against the one in your doctor's office to see if there is a difference in the readings.
American Heart Association. Home Blood Pressure Monitoring.
American Heart Association. Choosing a Home Blood Pressure Monitor.
dabl®Educational Trust. Classification of Sphygmomanometers.
Sheikh S et al. Home blood pressure monitoring: how good a predictor of long-term risk? Curr Hypertens Rep 2011;13(3):192-9.