Blood Pressure Cuffs Can
Be Very Inexpensive...
As most of the characteristics of blood pressure cuffs don't matter very much. But two of them do and can make all the difference.
It is impossible to discuss all the proprietary brands so we'll discuss the following aspects:
Types of Blood Pressure Cuffs
There are basically two types, the sleeve with an elastic rubber bladder inside and the one piece that has no bladder but serves both purposes. In other words the one piece is both sleeve and bladder.
Each and every one of the blood pressure cuffs must encircle the arm, be capable of being inflated and be elastic to return to the uninflated state.
Its ultimate function is to compress the arm enough to completely shut off all blood flow.
The early cuffs were non-elastic sleeves with a rubber bladder inside and worked well to this day. Newer ones do away with the bladder so the sleeve is also the bladder. All are connected by a hose to a means of inflation and deflation and by another hose to a meter to display the pressure inside the cuff. Some have a stethoscope affixed inside the sleeve but I basically disapprove of this. See Blood Pressure Monitor
The early cotton sleeves have competition from synthetic materials such as nylon. Newer materials have allowed a one piece design where the sleeve also functions as the bladder. This is not a big deal because the old two piece blood pressure cuffs worked fine. For the occasional laundering the bladder was removed and reinserted, sometimes with a little difficulty. The synthetic materials tend to feel cold on the bare arm but this discomfort, if you would call it such, is transient and in my estimation unimportant.
The American Heart Association recommends these widely accepted dimensions for a bladder: The bladder width must be 40% of the circumference of the mid-arm and the length must be double that or 80%. This equates to 6" wide for a 15" arm, 12" in length.
Most cuffs are fastened with Velcro these days as this is the easiest and lasts as long as you would want it to. Some people emphasize having a D-ring to make it easier to apply and position with one hand but you can get around that by pre-fastening the cuff and then slipping it on.
Positioning is the second most important characteristic of blood pressure cuffs. The edges must be parallel and even, the lower edge about one inch above the crease of the elbow and the arrow or the hose over the brachial artery (follow the manufacturer's instructions). Apply it snugly but it should still allow a finger to be inserted underneath.
You may have surmised by now that SIZE is the most important characteristic of blood pressure cuffs. This can introduce an error of up to 50 mm Hg. The bladder must encircle at least 80% of the mid-arm circumference. Too small cuff causes an error on the high side and too large cuff causes an error on the low side but not near as much.
Doctor's Practical Guide
The important characteristics here are positioning and especially SIZE. The others don't matter much unless the cuff is so poorly made as to be falling apart. To have wrong dimensions would be a scam of some sort. You must position it properly and use the proper size. Your arm size should fall within the middle 75% of the cuff range. If not don't use it.
If you have a large arm such as 32 cm (13 inches) and over you should consider carrying your own cuff to the doctor or the emergency room. See Blood Pressure Cuff This sister page will also help round out your knowledge of blood pressure cuffs in general.
If you are or might become pregnant and have a large arm you should read this website Large BP Cuff
To read Why and How you should learn to take your own blood pressure read this page
How to Take Blood Pressure
Follow Blood Pressure Cuffs with the Homepage