Blood Pressure Measurement

What is blood pressure measurement?

Blood pressure measurement is a quick, noninvasive test to find out if your blood pressure is normal. You can do it at home or a healthcare provider might do it for you. It’s the only test that can tell you if you have high blood pressure, which often doesn’t have symptoms until it’s severely high. Having high blood pressure can put you at risk for cardiovascular (heart and blood vessel) diseases.

When you take a blood pressure measurement, it tells you how hard your blood is pushing against the insides of your arteries. These are the blood vessels that deliver blood to your body’s tissues and organs so they can get oxygen and nutrients.

When is blood pressure measurement performed?

You can take a blood pressure measurement every day, but you should take it at the same time each day. For example, you may take it every morning at the same time and/or every evening at the same time.

Taking a few days’ worth of blood pressure measurements two weeks after starting a new blood pressure medicine can tell you if it’s working.

It’s also helpful to take blood pressure measurements a week before a checkup. This helps your healthcare provider know what a normal reading is for you at home. Some people have higher readings in their provider’s office (white coat syndrome). Other people get higher readings at home, so it’s good to have a mix of both in-home and in-office readings.

Your healthcare provider will check your blood pressure when they want to:

• Monitor your blood pressure while you’re getting treatment in the hospital.
• See if you have high or low blood pressure.
• See how well the medicine they prescribed is working for you.
• Find out what your risk is for cardiovascular (heart and blood vessel) diseases.
• Decide if certain medical procedures would be risky for you.
• Find out if you can do certain jobs or play sports.

How does blood pressure measurement work?

A blood pressure measurement device has a cuff that connects to a pressure gauge. When the cuff tightens around your arm, it temporarily blocks blood flow in that part of your arm. Loosening the cuff allows your blood flow to start again so you can find the minimum and maximum pressure in an artery.

What is the most accurate way to take blood pressure?

You can get the most accurate reading by preparing for your blood pressure measurement in these ways:

• Avoid tobacco products, foods, drinks, exercise and caffeine 30 minutes before blood pressure measurement.
• Use the bathroom so there’s no pee in your bladder.
• Rest for five minutes or more in a chair (not a couch) where you’ll take your blood pressure measurement.
• Make sure you’re sitting up straight with your legs uncrossed and your feet on the floor.
• Put the arm you’ll use on the table so your arm is at heart level and relax your arm.
• Use a cuff that isn’t too small for you. Most people can use a large adult cuff.
• Wrap the blood pressure measurement cuff around your upper arm (right above your elbow). You can use your left or right arm. Make sure your sleeve isn’t between the cuff and your arm. The cuff should touch your skin. Short sleeves are best so you don’t have to roll up your sleeve.

How to take blood pressure step by step

You should be calm and quiet during your blood pressure measurement. Don’t talk or watch a video on your phone.

If you have an automatic blood pressure measurement device, follow these steps:

1. Push a button to put air into the blood pressure cuff to make it tighter.
2. Wait while the cuff automatically releases air and takes measurements.

When you take a blood pressure measurement, you can take another one or two readings after waiting a minute between them.

How to take blood pressure manually

Healthcare providers sometimes take a manual blood pressure measurement using a stethoscope and a blood pressure cuff.

They’ll follow these steps:

1. Pump air into the cuff around your arm to tighten it.
2. Slowly release air from the cuff while using a stethoscope to hear the pulse in your arm’s brachial artery.
3. Take a measurement when they hear your blood moving.
4. Release more air from the cuff.
5. Measure your pressure again.

Often, providers will use an automatic machine to take your blood pressure measurement.

What to expect after blood pressure measurement

After a blood pressure measurement, you (or your provider) remove the cuff. You can go about your daily activities without any side effects from the test.

What are the risks of blood pressure measurement?

When the blood pressure cuff gets tight around your arm, you may feel uncomfortable. But the test only takes a minute and the tightness lasts a shorter time than that.

What type of results do you get and what do the results mean?

You’ll know your results right away. You’ll get two numbers:

• The top, first or systolic number is the pressure in your arteries during a heartbeat.
• The bottom, second or diastolic number is the pressure in your arteries when your heart’s resting to prepare for the next beat.

You may record these as the first and second numbers with a slash between them, like 120/80. Results are in millimeters of mercury (mmHg).

Blood pressure readings can be low, normal or high.

• Normal is 120/80 mmHg or lower.
• Elevated is 120 to 129/80 mmHg or lower.
• Stage 1 high blood pressure is 130 to 139 mmHg or 80 to 89 mmHg.
• Stage 2 high blood pressure is 140/90 mmHg or higher for either number.
• Hypertensive crisis is higher than 180 mmHg and/or higher than 120 mmHg.

Different age groups and illnesses (like recent stroke) might mean that your personal blood pressure goal is different from the typical adult levels. It’s important to work with your primary care doctor, cardiologist, nephrologist or whoever’s primarily managing your blood pressure to make sure you know your personal blood pressure goal.

If the results are abnormal, what are the next steps?

One high blood pressure reading doesn’t mean you have high blood pressure.

To diagnose you with high blood pressure, your provider will need two or more high readings from separate visits. And they’ll use a lot of data points over time.

If your provider confirms that you have high blood pressure, they can prescribe medicine for you. Many different types of medications can treat high blood pressure. Your provider will use your medical history to help choose one that works for you. Some people with high blood pressure need to take two or three different pills to manage their blood pressure.

In addition to or instead of taking medicine, you may need to make changes to your daily life, such as:

• Staying at a weight that’s healthy for you.
• Exercising for 150 minutes every week.
• Eating fewer than 1,500 mg of salt in a day.
• Eating lots of whole grains, fruits and vegetables, and fewer saturated fats.
• Avoiding tobacco products.
• Drinking no more than one or two alcoholic drinks per day.

When should I call my doctor?

If you get a high reading, wait and check again. If you keep getting high readings, contact your provider. Call right away if your numbers are in the hypertensive crisis range.

Get immediate help if your numbers fall in the hypertensive crisis range and you’re having symptoms like:

• Shortness of breath.
• Chest pain.
• Pain in your back.
• Vision changes.
• Trouble with talking.
• Numbness.
• Headache.

If your blood pressure is too low, it’s also important to seek medical attention. Some symptoms of low blood pressure include:

• Fatigue.
• Dizziness.
• Lightheadedness.
• Syncope (fainting).

A note from Cleveland Clinic

Blood pressure measurement is a useful tool that can help your provider assess your health. Knowing how to take your blood pressure at home can give you the freedom to check it at your convenience. A blood pressure measurement can give you peace of mind if your results are good. It can also alert you to a possible need for treatment for high blood pressure, which has no symptoms. Don’t panic if you have one high reading. It takes more than that for a diagnosis.