Ambulatory Blood Pressure Monitor (ABPM)
Ambulatory blood pressure monitor
Ambulatory blood pressure monitoring is a way of measuring and managing high blood pressure. High blood pressure (hypertension) means your top number (systolic blood pressure) is at least 130 mmHg (millimeters of mercury), and/or your bottom number (diastolic blood pressure) is at least 80 mmHg.
Ambulatory blood pressure monitoring records your blood pressure (BP) readings over a 24-hour period, whether you’re awake or asleep. This happens outside your healthcare provider’s office, as you go about your daily life. You wear a cuff on your arm and a small device attached to a strap or belt.
Ambulatory blood pressure monitoring takes dozens of readings over a continuous period. In most cases, the device records readings every 15 to 30 minutes during the day and every 60 minutes at night. The device also measures your heart rate (how fast your heart is beating). Your provider uses this data to calculate your average BP over the 24-hour period. They also calculate changes in BP and heart rate, BP distribution pattern and other statistics.
Who needs ambulatory blood pressure monitoring?
Ambulatory blood pressure monitoring can help a wide range of people. Your healthcare provider may recommend ambulatory blood pressure monitoring if you:
Have high blood pressure based on readings at your provider’s office, but you haven’t yet started treatment.
Need changes to your blood pressure medications.
Still have high blood pressure despite medications.
Are taking other medications that may affect your blood pressure.
Have fainting episodes or hypotension (low blood pressure).
How is ambulatory blood pressure monitoring done?
Ambulatory blood pressure monitoring happens outside of your healthcare provider’s office. But to get things started, you meet with your provider for an appointment. This is when you receive your equipment and instructions for the 24 hours.
Here’s what happens at your appointment:
You receive your equipment. This includes a small device that’s about the same size as a portable radio. You wear this on a belt or strap. You also have a BP cuff around your arm. Tubing connects the cuff to the device.
Your provider fits the cuff on your arm and sets up your device. Once everything is properly fitted, your provider begins recording data.
You receive instructions. Your provider gives you detailed instructions that you should closely follow. Be sure to ask any questions you might have before you leave your provider’s office. When you leave, the equipment stays on you. Your provider will tell you what time to remove it and when to bring it back.
Here’s what happens once you’re home:
Your arm cuff inflates at certain intervals. This may be every 15 to 30 minutes during the day, and every 60 minutes at night. Inflation means the device is measuring your BP. You may feel the cuff squeezing your arm. This is brief. Keep your arm still during these moments to get the most accurate measurements.
You may have disrupted sleep. You may wake up periodically when the device begins measuring your BP. This is normal. But try your best to ignore the sensation and get back to sleep.
You follow your normal routine. Do what you normally do, but avoid bathing or swimming. Also, avoid heavy exercise. Keep a journal as your provider instructs.
You take your medications as your provider directs. Ask your provider whether or not you should continue your medications while ambulatory blood pressure measurement is in progress. Follow their guidance closely.
Test Details
How do I prepare for ambulatory blood pressure monitoring?
Your healthcare provider will tell you how to prepare. Some general tips include:
Choose a 24-hour period that best represents your normal routine. This may mean choosing a weekday rather than a weekend.
Plan to keep a journal of what you do during the 24-hour period. This includes when you wake up and go to bed, when you take any medications and when you eat. You should also record any symptoms you experience (likedizziness or shortness of breath).
Engage in strenuous physical activity.
Shower or swim.
Remove any part of the device without first asking your doctor.
Results and Follow-Up
What type of results do I get and what do they mean?
Your healthcare doctor will transfer the data from the device to a computer, which analyzes your BP readings. Your doctor will talk to you about your results and what they mean for you.
Some results your doctor may discuss with you include:
24-hour average blood pressure. This is your average BP reading from the entire monitoring period.
Daytime blood pressure. This is your typical BP during the hours you’re awake
Nighttime blood pressure. This is your typical BP during the hours you’re asleep.
Nocturnal dipping patterns. This is the difference between your daytime and nighttime BP readings. Your nighttime reading should be lower.
Risk?
This method of BP monitoring, though noninvasive, may still be uncomfortable for some people. Disadvantages include:
Arm soreness. Pressure due to repeated inflation of the cuff may make your upper arm sore.
Sleep disruption. BP readings during the night may interfere with your sleep.
Skin irritation. The cuff may irritate your skin and cause a mild rash that usually goes away on its own.
Possible cost. Some insurance providers only reimburse you for ambulatory devices in specific cases. These include if your provider suspects you have white coat syndrome or masked hypertension. Talk to your provider about what costs you may expect.
How do you sleep with an ambulatory blood pressure monitor?
You may have trouble sleeping, and that’s understandable. You’re not used to having a cuff on your arm when you sleep. But try your best to relax. Do whatever you can to make the rest of your sleep environment comfortable. You may want to:
Play soothing music.
Cover your windows to block out any strong light.
Set your thermostat to a temperature that’s comfortable for you (not too warm or too cold).
Your provider will tell you how you may adjust your equipment while you sleep. For example, you may be able to remove the strap from your body and place it next to your pillow. Only do this if your provider says it’s OK. You shouldn’t remove the arm cuff until the end of your monitoring period.
Talk to your provider about what you can do to get the best quality sleep.
