Blood pressure cuffs – the right size matters

Die passende Manschetengr÷¯e ist wichtig

People are different and so are their (upper) arms. Just like clothing sizes, people need different sizes of blood pressure cuffs. For accurate readings the cuff must fit. If it doesn't, the measurements can be misleading.

The standard cuffs supplied with blood pressure monitors have a length and width that fit many people. But if the user has a very large or very small upper-arm circumference, a larger or smaller cuff must be chosen. The cuff should snugly encircle the upper arm not too loose, but not too tight and the inflatable section must be long enough but not overly long. The width also needs to be chosen correctly. Common standard cuffs are usually 1213 cm wide; for an upper-arm circumference of 33 cm or more, a 1518 cm cuff, or sometimes even wider, is recommended.

For very slim arms, the cuff should be correspondingly smaller and possibly narrower. Sometimes a child-sized cuff is the right choice.

How can readings be distorted?

In people with a very slim arm, the standard cuff can be too large. This can lead to readings that are too low. In one study, using a too-large cuff resulted in systolic values that were on average 3.8 mmHg lower and diastolic values 1.5 mmHg lower.

If the cuff used is too small for the arm inside it, the opposite happens: readings can be falsely high. The worse the mismatch, the larger the error. In that study, for arms that should have used an L cuff, systolic readings were 3.8 mmHg higher and diastolic readings 1.5 mmHg higher. For arms that should have used an XL cuff, systolic measurements were up to 19.7 mmHg too high. Diastolic values were up to 7.4 mmHg too high.

Upper arms can be too large for a standard blood pressure cuff for various reasons. Often overweight or obesity are the cause, but very muscular arms can also require a larger cuff.

Special case: lipedema

Lipedema is a special case. This chronic condition is a disorder of fat distribution with an abnormal increase of subcutaneous fat tissue, which can also affect the arms. As a result, the upper-arm circumference can become very large. Because of the tissue changes, blood pressure measurement is often perceived as very painful and can cause bruising. It's important to carefully consider which device might be suitable and to test individually whether the measurement can be tolerated. Unfortunately, blood pressure monitors are not currently tested for their suitability in this condition.

Wrist blood pressure monitor

If measurement with an upper-arm blood pressure monitor is not possible, a wrist monitor can be an alternative, provided the user has no known arteriosclerosis. Arteriosclerosis could narrow the relatively smaller vessels at the wrist and thus distort the measurement. If you choose a wrist monitor, you must be extremely careful to perform the measurement correctly in order to obtain accurate results. Because of their design, wrist monitors offer limited options for different cuff lengths and widths. However, there are sometimes small differences between individual devices, so there is still some choice.

Conclusion

So it's a good idea to measure your arm circumference before buying a blood pressure monitor and then look specifically for a device that offers a suitable cuff. Various manufacturers offer additional cuff sizes as options for their upper-arm monitors. For wrist monitors, additional cuff sizes are rarely available because of the device design. Still, sizes can vary somewhat between devices, so a suitable one can often be found. Please note the exclusion criteria for wrist measurements. If a wrist monitor is appropriate for you, be sure to perform the measurement correctly with the measurement point at heart level.

Sources:

This article comes from BloodPressureDB – the leading app since 2011 that helps hundreds of thousands monitor their blood pressure every day. Our content is based on carefully researched, evidence-based data and is continuously updated (as of 12/2023).

Author Sabine Croci is a qualified medical assistant with many years of experience in internal medicine and cardiology practices as well as in outpatient care, and has led BloodPressureDB's specialist editorial team since 2015. Thanks to her extensive additional qualifications as a paramedic, first responder and in various therapy and emergency areas, she provides solid, practical and reliably reviewed information.

We hope you found the article helpful. Accurate measurements are essential for good blood pressure control. Our app BloodPressureDB can help with that. Clear instructions walk you through taking measurements according to current guidelines. The app can also remind you if you wish. These features are fully available in the free version as well. Get the free app now.