What is blood pressure?
Blood pressure provides clues about how well your heart is working to pump blood through your arteries. It’s one of your body’s four major vital signs. The other vital signs are:
- body temperature
- heart rate
- breathing rate
Vital signs show how well your body is functioning. If a vital sign is too high or too low, it’s a sign that something may be wrong with your health.
Blood pressure is measured using two different readings. The first reading is called your systolic pressure. That’s the first or top number in a reading. The second reading is your diastolic number. That one is the second or bottom number. For example, you may see blood pressure written as 117/80 mm Hg (millimeters of mercury). In that case, the systolic pressure is 117 and the diastolic pressure is 80.
Systolic pressure measures the pressure inside of the artery when the heart is contracting to pump blood. The diastolic pressure is the pressure inside the artery once the heart is resting.
Higher numbers in either recording can show that the heart is working extra hard to pump blood through your arteries. This may be the result of an outside force, like if you’re stressed or scared, which causes your blood vessels to become more narrow. It could also be caused by an internal force, such as buildup in your arteries that can cause your blood vessels to become narrower.
If you’d like to check your own blood pressure at home, it’s best to first check with your doctor about how they would like you to monitor and record it. For example, your doctor may prefer you to check your blood pressure before or after a certain medication, at certain times of the day, or when you’re stressed or feeling dizzy.
How to use an automated blood pressure machine
The easiest way to take your own blood pressure is to purchase an automated cuff. Automatic blood pressure machines are the easiest to use, and they’re helpful if you have any hearing impairments. These types of blood pressure cuffs have a digital monitor that will display your blood pressure reading on a screen. You can purchase these online, at most grocery stores, or at a health food store.
The American Heart Association recommends an automatic, upper arm blood pressure monitor for at-home use. To use your digital blood pressure monitor, follow the instructions that come with it. You can also take the monitor to your doctor’s office, or even your local pharmacy, for a demonstration.
You should also purchase a small notebook to start a blood pressure log. This can be helpful for your doctor. You can download a free blood pressure log from the American Heart Association.
Machines can give you a different reading than a manual blood pressure reading. Bring your cuff to your next doctor’s appointment so you can compare the reading from your cuff to the reading your doctor takes. That can help you calibrate your machine and identify levels you should look for on your own device. It’s also important to purchase a high-quality machine and monitor for errors. Even if you check your blood pressure at home, your doctor will still want to manually check it during appointments.
How to check your blood pressure manually
To manually take your blood pressure, you’ll need a blood pressure cuff with a squeezable balloon and an aneroid monitor, also known as a sphygmomanometer, and a stethoscope. An aneroid monitor is a number dial. If possible, enlist the help of a friend or family member, because it can be difficult to use this method on your own.
Before taking your blood pressure, make sure you’re relaxed. Position your arm straight, palm facing up on a level surface, such as a table. You’ll place the cuff on your bicep and squeeze the balloon to inflate the cuff. Using the numbers on the aneroid monitor, inflate the cuff about 20-30 mm Hg over your normal blood pressure. If you don’t know your normal blood pressure, ask your doctor how much you should inflate the cuff.
Once the cuff is inflated, place the stethoscope with the flat side down on the inside of your elbow crease, where you can see the major veins in your arm. Be sure to test the stethoscope before using it to make sure you can hear properly. You can do that by tapping on the stethoscope. It’s also helpful to have a high-quality stethoscope and to ensure that the ears of the stethoscope are pointed in toward your eardrums.
Slowly deflate the balloon as you listen through the stethoscope to hear the first “whoosh” of the blood flowing, and remember that number. This is your systolic blood pressure. You’ll hear the blood pulsing, so keep listening and allow the balloon to slowly deflate until that rhythm stops. When the rhythm stops, record that measurement. This is your diastolic blood pressure. You’ll record your blood pressure as the systolic over the diastolic, such as 115/75.
Apps to track blood pressure
Although there are apps that promise to check your blood pressure without using equipment, this isn’t an accurate or reliable method. However, there are apps available that can help you track your blood pressure results. This can be helpful in identifying patterns in your blood pressure. Your doctor may use this information to determine if you may require blood pressure medications.
Some examples of blood pressure monitoring apps include:
- Blood Pressure Monitor – Family Lite (iPhone): You can enter your blood pressure, weight, and height, as well as track the medications you take.
- Blood Pressure (Android): This app tracks your blood pressure and features several statistical and graphical analysis tools.
- Blood Pressure Companion (iPhone): This app allows you to track your blood pressure as well as view graphs and trends on your blood pressure readings across several days or weeks.
These apps can help you quickly and easily track your blood pressure readings. Measuring your blood pressure at the same time every day on the same arm can help you most accurately track your blood pressure readings.
What does your blood pressure reading mean?
If this is your first time taking your blood pressure, discuss the results with your doctor. Blood pressure is a very individualized vital sign reading, which means it can be very different for each person. Some people have naturally low blood pressure all the time, for example, while others may run on the higher side.
In general, a normal blood pressure is considered anything less than 120/80. Your own personal blood pressure will depend on your gender, age, weight, and any medical conditions. If you do register a blood pressure reading of over 120/80, wait 2-5 minutes and re-check. If it’s still high, you should talk to your doctor to rule out hypertension. If your blood pressure ever goes over 180 systolic or over 110 diastolic after a repeat reading, seek emergency medical care right away.
Blood pressure chart
While everyone is different, the American Heart Association recommends the following ranges for healthy adults:
|normal||less than 120||less than 80|
|high blood pressure stage 1 (hypertension)||140-159||90-99|
|high blood pressure stage 2 (hypertension)||160 or higher||100 or higher|
|hypertensive crisis (call your local emergency services)||higher than 180||higher than 110|
When determining the category you fall into, it’s important to remember that both your systolic and diastolic numbers need to be in the normal range for your blood pressure to be considered normal. If one number falls into one of the other categories, you will be considered to be in that category. For example, if your blood pressure was 115/92, you’d be considered high blood pressure stage 1.
Monitoring your blood pressure can help you and your doctor identify any issues early on. If treatment is needed, it’s better to start it earlier before any damage has occurred in your arteries. Treatment may involve lifestyle changes, like a balanced diet low in salty or processed foods, or adding exercise to your regular routine. Sometimes you’ll need to take blood pressure medication, like:
- calcium channel blockers
- angiotensin converting enzyme (ACE) inhibitors
With proper treatment, you should be able to control your blood pressure.
Tips for purchasing a blood pressure cuff
To get the most accurate blood pressure reading, remember the following tips:
- Make sure the blood pressure cuff is the right size for you. Cuffs come in different sizes, including pediatric sizes if you have very small arms. You should be able to comfortably slip one finger between your arm and the cuff when it’s deflated.
- Avoid smoking, drinking, or exercising 30 minutes before taking your blood pressure.
- Be sure to sit with your back straight and your feet flat on the floor. Your feet should not be crossed.
- Take your blood pressure at different times of the day and record exactly what time each blood pressure measurement is taken.
- Rest 3-5 minutes before taking your blood pressure and a few extra minutes if you’ve recently been very active, such as exercising.
- Bring your own at-home monitor to your doctor’s office at least once a year to calibrate it and make sure it’s working correctly.
- Take at least two readings every time to make sure they’re correct. The readings should be within a few numbers of each other.
- Take your blood pressure at the same times every day, such as before breakfast, over a period of time to get the most accurate readings.
Q&A: White coat syndrome
I think I have white coat syndrome. My blood pressure is always high when my doctor checks it, but normal when I check it at home. Is there anything I can do to get over my white coat syndrome?
Deep breathing prior to having your blood pressure checked may help lower blood pressure. There’s no downside to relaxing with a few slow deep breaths, so it would be worth a try.Carissa Stephens, RN, BSN, CCRN, CPNAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.