Lot of people are not aware that the cuff size plays a major role in getting accurate blood pressure readings. Cuff is an inflatable bladder encased in a cloth, which you wrap around the arm to measure blood pressure. If you feel, you are getting false blood pressure readings, then it may happen because of cuff, rather than monitor. Monitors are generally pass through stringent specifications and tend to be accurate. In this article our focus is on arm based monitors. Appropriate fitting plays an important role even for wrist monitors accuracy.
How to measure size of your arm
You need to use the cuff which is appropriate for your arm. To decide which cuff size is suitable for you, first you need to know the size of your arm. Measure the circumference of upper arm midway between elbow and shoulder using flexible cloth tape (not the metal one).
Appropriate Cuff Size
The cuff should not be too large or too small for your arm. The inflatable part of the cuff should cover 80% of the circumference of the upper arm and it should cover 2/3rd of the distance from your elbow to shoulder.
It is not just Fit. The criteria is an appropriate size cuff which fits properly and get wrapped around your arm conveniently without causing any discomfort.
The following are the ways to ensure that you wrapped cuff correctly:
- Make sure to remove any tight fitting cloth from your upper arm before wrapping the cuff on the arm..
The cuff is said to be secured firmly, if it is difficult to slide 2 fingers under the cuff.
Other than cuff size you also need to take few other steps for accurate measurement.
Proper cuff fitting is important for blood pressure measurement. For measuring pressure, lot of digital Blood Pressure Monitors (BPM) uses Oscillometric method which detects your blood’s movement through your brachial artery and then converts this movement into a digital reading. If you have a large arm and the cuff is too tight for you then, the machine may show higher readings than normal. In addition, if you have smaller arm, and large cuff, then it takes more time to inflate and may possible that no readings get displayed, since cuff did not inflate properly because it is loose.
There are many blood pressure monitors brands available in the market and they sell cuff as separate accessory. Some BPM comes with standard cuff size such as Lifesource UA-767, if you have larger arm then you have to order extra cuff. Some brands have cuff which are fit for all such as Omron 10 Series, Omron 7 Series, then whether you have large or small hands, the cuff fits you appropriately.
Standard Cuff Sizes
|Cuff||Arm Size (cm)||Arm Size (inches)|
|Small Adult/Child||22-26 cm||8.6" to 10.2"|
|Adult||27-34 cm||10.6" to 13.38"|
|Large Adult||35-44 cm||13.7" to 17.3"|
|Adult thigh Cuff||45-52 cm||17.7" to 20.4"|