Choosing the right blood pressure monitor

There is a massive range of blood pressure monitors on the market, most of which are accompanied by impressive claims about quality and accuracy from the retailer or manufacturer. This page aims to make the selection process easier by explaining the differences between the various types, and by shedding light on the various features. It will also explain what clinical validation is.

The types of blood pressure monitor available

Fully Automatic - a blood pressure monitor with a cuff that inflates using a mechanically driven electric pump;

Manual - the cuff is inflated by squeezing a rubber bulb;
Manual blood pressure monitors that have an electronic display are usually called semi-automatic. This is because the unit will still automatically work out the systolic and diastolic pressures in the same way as a fully automatic machine.

Blood pressure monitors also vary in the moment during the inflation/deflation cycle that blood pressure is actually taken. The oldest method is for the reading to be taken as the cuff deflates. The technology for this is reliable and well established. However some very modern machines take the reading during inflation. This has the advantage of giving a faster reading, and is also gentler on the arm or wrist because the monitor will never inflate more than necessary.

Blood pressure monitors always have a cuff which fills with air as the reading is taken. This wraps around the arm and is secured with a velcro grip. A blood pressure reading can either be taken at the upper arm, or at the wrist. It is very important that the blood pressure reading is taken at the same level as the heart and that the arm remains still throughout the course of the reading. Upper arm type blood pressure monitors tend to be more accurate because it is easier to keep the cuff at the right height. However they can be troublesome to put on and it is important to make sure that they are correctly placed about 1 inch above the crease of the elbow. Wrist type blood pressure monitors have the advantage of being more portable and very easy to put on. With a bit of practice it should be possible to get accurate blood pressure reading from both types. It is advisable to get a trained professional to show you how to operate either type in order to ensure correct use.

Clinical Validation

If a blood pressure monitor has been clinically validated, it means that an independent body, usually a research institute or university, have tested it for accuracy. This will normally involve comparing the performance with blood pressure readings taken using mercury sphygmomanometer, a method that is considered completely scientifically reliable. During the test series of blood pressure readings will be taken, and the monitor will be given a validation if it performs sufficiently closely to the reliable control readings. The British Hypertension Society keeps an up to date record of blood pressure monitors which have performed well enough in these types of to be recommended on their web site. The following table gives an up to date list of recommended models.