What is an ambulatory (24hr) blood pressure monitor?
An ambulatory blood pressure monitor is a small portable wearable device that is used to record your blood pressure at regular intervals over a 24 hour period, including while you are asleep. It provides a series of consecutive automated blood pressure readings via blood pressure cuff that is left on your arm for the whole recording period. The cuff is attached to a small recorder that is worn on a belt or strap around your chest or waist. The information it obtains is stored on the device and then downloaded onto a computer for analysis and printing.
Why is it done?
There are a number of reasons why your doctor may order a 24 blood pressure monitor test for you.
Diagnosis of hypertension (high blood pressure). A series of blood pressure measurements covering both daytime and night is a more accurate way to diagnose high blood pressure than simply checking one or two readings in your doctor’s office. Both the average of the readings and the percentage of readings that are elevated are used when trying to confirm a diagnosis of hypertension.
Monitoring the effects of treatment. People with hypertension may undergo blood pressure monitoring to determine if their treatment is effective.
How is it done?
A standard arm cuff of an appropriate size is put on your arm by one of our technicians. This is usually put on your non-dominant arm and attached to a small battery powered pump and recorder. The pump inflates the pressure to above your maximum (systolic) blood pressure and gradually releases the pressure to below the minimum (diastolic) blood pressure. It is important that your arm is kept still during this measurement. If the machine is fails to get an accurate reading it will attempt to do so again.
If your blood pressure is very high the recorder will have to pump the cuff up to a higher pressure and this may be uncomfortable. However, if pain or any other worrying symptoms occur, it is best to remove the device and turn it off.
There are no special preparations. Loose fitting clothes may be more convenient as the device is placed under your shirt or top. Normal underwear can be worn. It is important that we know what medications you are taking at the time of the test. An easy way is to bring all your medications with you when you come to have the monitor fitted.
You cannot bathe or shower during the test as the device is not waterproof. You should take part in all other life activities.
Normally the monitor is removed in our office the following day. However, it can be removed, switched off and brought to the office by someone else for you if needed. Our office will provide more instructions about this at the time of fitting.
What happens after the monitor is removed?
Our technical staff analyse the recording and prepare a preliminary report that is then reviewed and finalised by a cardiologist. This usually takes 1-3 days. Our office will advise you how the results will be communicated to you and your doctors.