This leaflet answers common questions about having your blood pressure monitored over a 24-hour period. If you would like further information, or have any worries, please do not hesitate to ask your nurse or doctor.  

In all cases, a doctor will explain the procedure to you and answer any questions you may have. 

What is 24-hour blood pressure monitoring?

24-hour blood pressure monitoring is when your blood pressure is measured as you move around, living your normal daily life, over a period of 24 hours. Your blood pressure is measured using a small digital blood pressure machine that is attached to a cuff on your arm.

By measuring your blood pressure at regular intervals over 24 hours, we can see how your blood pressure changes throughout the day and night.

Your doctor may have requested you undergo this test so that we can see:

  • If your blood pressure readings in the clinic are much higher than they are away from the clinic
  • How well your medicines are working to control your blood pressure throughout the day
  • If your blood pressure stays high at night, which may mean that we must adjust the medicines you are taking.

How is a 24-hour blood pressure monitor fitted?

You will be invited into a private consultation room. The person fitting your blood pressure monitor is called a cardiac physiologist. In most cases it will be possible for a friend or relative to accompany you during your fitting.

You will be asked to undress to the waist and a blood pressure cuff will be placed on your non-dominant upper arm (for example, your left arm if you are right-handed). The monitor is set up to take regular readings every 20 minutes during the day and every hour during the night. The monitor itself can be worn on a belt or around your waist.

You will be shown a button (black or green) that you will need to press to switch off the monitor once the 24 hours of recording are completed. Your appointment will take up to 20 minutes. 

Before your appointment

Please continue to take any medication as normal. If you require a male or female cardiac physiologist please contact us before your appointment, and we will do our best to accommodate your request.

After your appointment Once the blood pressure monitor is fitted, you can get dressed and you are free to leave.

You will be given a date and time by the cardiac physiologist to return the monitor. Please remember to do this as delays in returning monitors can mean monitors are not available to other patients.

Your result will be sent to your referring doctor in time for your next appointment with them.

Important advice when using the monitor

The monitor must always be kept dry. Please do not swim, shower, or take a bath with the monitor attached to you.

Please keep your arm steady when you feel the cuff inflating/deflating. Any arm movement could confuse the measurement which may result in an error and the machine having to repeat the measurement.  

Do you have any further questions?

If you have further questions, or to rearrange your appointment, please contact us via one of the numbers below:  

Royal Free Hospital

Tel: 020 7794 0500, extension 31995

Barnet Hospital, Chase Farm Hospital, and Edgware Community Hospital

Tel: 020 8216 4552