What Is a Blood Pressure Monitor and Why Would You Need One?
Your blood pressure reading at the doctor’s office only shows your numbers at that moment. A home monitor lets you check it often, which can give your doctor a better idea of your true blood pressure. The best way to know if you have high blood pressure is to measure it several times a day for a few months.
Do you plan to start using a blood pressure monitor? You’re part of a growing group. Doctors are telling more and more people with high blood pressure to check their numbers at home.
There are many home blood pressure monitors to choose from. Many cost less than $100. You don’t need a prescription to get one. You can find them at your local pharmacy, a discount store, a medical supply store, or online.
You can even choose a model to wear on your arm or wrist during the day. But not all of these are accurate. That’s why it’s important to bring your blood pressure monitor to the doctor before you start using it. They can test it against the ones used in their office.
How Do Blood Pressure Monitors Work?
Arm blood pressure monitor
There are two ways to check your blood pressure using an arm monitor:
- By hand (manually). After wrapping a blood pressure cuff around your arm, inflate it using a small hand pump. Using a stethoscope on your upper arm, you'll listen to your pulse and blood flow.
- By machine. With this method, the cuff automatically fills with air. You'll feel it tighten around your arm as it fills.
After the blood pressure cuff fills up, you'll let the air out slowly. Note the pressure when you first hear your pulse; that's your systolic pressure (the top number in a blood pressure reading). As you keep letting out air, the sound of your pulse will fade. When it's completely gone, you'll note another pressure reading; that's your diastolic pressure (the bottom number). Normal blood pressure is 120 over 80 or less, while high blood pressure is 130 over 80 or higher.
Wrist blood pressure monitor
Like an arm monitor, a wrist blood pressure monitor measures the pressure of blood as it flows through your arteries. The difference is that a wrist monitor takes measurements where your wrist connects with your hand, at your radial artery. You'll secure the cuff around your wrist and put your elbow onto a table. Then, you'll put your hand on your chest, making sure that your wrist is at heart level. Relax and stay still while the monitor takes your blood pressure.
Arm Blood Pressure Monitors
Arm blood pressure monitors come with cuffs that wrap around your upper arm.
Types of arm blood pressure monitors
There are two basic types of monitors that use an arm cuff:
Aneroid monitors: You squeeze a bulb to inflate the cuff around your upper arm. Then you read a gauge to find your blood pressure. These are the least expensive options, but they’re also easy to damage.
Digital monitors: On some models, you inflate the cuff, while on others, the machine does it for you. Your reading appears on a small screen. Some even offer a paper printout. They’re easy to use and read.
Pros and cons of arm monitors
Compared to a wrist monitor, the pros of an arm blood pressure monitor include:
- It provides a more accurate reading.
- Doctors suggest them more often.
Cons include:
- It may not fit well on your upper arm.
- Certain medical conditions make wearing an upper arm cuff unsafe or painful.
Blood pressure cuff size
It's important to make sure the blood pressure cuff fits your arm. You should be able to wrap it comfortably around your arm with enough room to slide two fingers underneath the cuff. You'll probably get a medium-sized cuff with your monitor. If it doesn't fit, you may need to buy one separately.
Wrist Blood Pressure Monitors
You use a wrist blood pressure monitor to measure your blood pressure outside of the doctor's office. It will either have a cuff that you wrap around your wrist with an attached digital display to show your readings, or it can come as a wearable, like a watch.
Pros and cons of wrist blood pressure monitors
Pros include:
- It's small, lightweight, and you can carry it with you.
- It can be more comfortable than arm monitors.
Cons include:
- Wrist measurements are sensitive to the position of your body.
- Blood pressure readings are less accurate.
24-Hour Blood Pressure Monitor
This type, also called ambulatory blood pressure monitoring, measures your blood pressure around the clock, even while you sleep. It helps your doctor to get precise data about your blood pressure and make treatment suggestions. It works by taking readings every 15 to 30 minutes when you're awake and every hour while you sleep. You'll wear an arm cuff, and the monitoring device attaches to a strap or belt.
Features to Look For in a Blood Pressure Machine
When choosing a blood pressure monitor, there are many features to consider, including:
- An irregular heartbeat detector
- A risk-category indicator, which shows whether your blood pressure is normal or high
- Multi-user, downloadable memory
- Multiple cuffs
- A display with large numbers
- A data-averaging function
Do home blood pressure monitors read higher?
Sometimes they can. If you've noticed that your blood pressure measurements are higher at home than at your doctor's office, it could be due to:
- A mistake in taking your blood pressure at home
- Lower stress levels at your doctor's office (called "masked hypertension")
- The use of alcohol, caffeine, or cigarettes at home
How to calibrate a blood pressure meter?
You should get your blood pressure monitor serviced and calibrated every couple of years. This means you'll likely need to send it back to the company that made it, and they'll probably charge a fee for this service.
Blood Pressure Monitor Apps
Many smartphone apps claim to measure blood pressure, but can you trust the results?
Studies have found that smartphone apps could help monitor blood pressure and might be useful for ongoing, noninvasive health care. But there are concerns about how accurate these apps are. One well-known app, Instant Blood Pressure (IBP), is no longer for sale. A small study found that more than three-quarters of people with high blood pressure using the app wrongly thought their blood pressure was OK. More research is needed to make sure apps are reliable for checking blood pressure. The FDA doesn't regulate blood pressure apps since it doesn't consider them to be medical devices.
How do apps monitor blood pressure?
They work in various ways. Some allow you to connect your blood pressure monitoring device to an app and then share the information with your doctor. Other apps use the camera on your smartphone to take a blood pressure measurement. Many apps simply serve as a logbook or diary of your blood pressure measurements, remind you to take your blood pressure, and offer educational information about the condition.
Shopping Tips
The home blood pressure monitor you choose should be the one that’s right for you, not necessarily the one your friend or neighbor likes. Follow this smart shopper checklist:
Make sure it fits. An arm cuff that’s the wrong size can affect your readings. Your doctor, nurse, or pharmacist can tell you what size you need.
It’s OK to be frugal. A high-tech wireless monitor can cost $200, but it may not be better or more accurate than a much less expensive model. Many top-rated blood pressure monitors cost between $40 and $75. Check to see if your insurance company will cover it.
Think about features you really need. Only spend money on the features you'll use regularly.
Ease of use. Some monitors may be simpler to use and read than others. Try out a few before you choose.
Talk to your doctor. They can help you decide which monitor is best for your needs, make sure you're using it the right way, and check the accuracy of its results.
Takeaways
Home blood pressure monitors help you and your doctor to get a more accurate picture of your blood pressure over time, rather than just a snapshot from a doctor's visit. They're widely available and affordable, with many options under $100 and no need for a prescription. You can buy an arm monitor or a wrist monitor. Wrist monitors may be less accurate. When choosing a monitor, it's important to pick one that fits well, fits your budget, and has the features you need, such as multiple cuffs or user profiles.
Blood Pressure Monitor FAQs
Which arm should blood pressure be taken on, left or right?
The American College of Cardiology, American Heart Association guidelines, and Joint National Committee suggest that when checking blood pressure for the first time, you should measure it in both arms. If there's a difference between the readings, use the arm with the higher blood pressure.
Is there a free blood pressure app available?
Yes, several free blood pressure monitoring apps are available in your app marketplace.