24 hour ambulatory monitoring

This is the name given to the form of blood pressure monitoring which is carried out within a 24 hour period.

This involves you wearing a small blood pressure monitor which is attached to your person. This device records your blood pressure throughout the day and even into night time.

Why 24 hour monitoring?

Your GP may advise you to undergo this to find out more about why your blood pressure fluctuates throughout the day. There are likely to be various reasons for this which includes:

• ‘White coat hypertension’: a form of high blood pressure which occurs when you undergo a blood pressure check at your GP’s surgery.
• Medication: it is a useful means of assessing how well your medication is working to control your high blood pressure.
• Blood pressure and night time: this will be carried out to see if your blood pressure remains high throughout the night. If it does then your medication will need adjusting.

The blood pressure monitor is available from your local hospital although it can be fitted at your GP’s surgery.

This type of monitor is much the same as the normal blood pressure you see in your GP’s surgery. You still wear an arm cuff as normal and your blood pressure is recorded in the same way.

The 24 hour blood pressure monitoring procedure

So what does it entail? To start with you will be fitted with this monitor. The blood pressure monitor is worn on a belt around your waist which is connected to an arm cuff. The arm cuff remains in place for the full 24 hours.

Please ensure that the belt does not become twisted or caught on another item of clothing.

The monitor will take readings at regular intervals within the 24 hour period. These are usually every 15 to 30 minutes in the day and 30 minutes to an hour at night.

The device will inform you that it is about to take a blood pressure reading by means of a bleep. As soon as you hear that bleep, keep your arm still and ensure that the cuff is halfway between your elbow and shoulder. Sit down if possible.

The device will also bleep in the night: prepare for this by placing the device under your pillow or closer to hand on your bed.

It is important to carry on with the same routine as normal. Don’t do anything different but avoid having a shower or going swimming within that time period.

You will be asked to keep a written record during this period. Treat this as a form of a diary and note down the following before you take a reading:

• What activity you were doing
• How you were feeling at that time
• What time you woke up
• What time you went to bed
• What meals you ate
• What medication you took

Some people find this both irritating and stressful. If you feel like this about this procedure then speak to your GP about an alternative.

If you are stressed, anxious or resentful during this 24 hour period then it will be reflected in the readings.