When I first learned to take blood pressures, automatic cuffs (which we called sphygmomonometers, to show you how old I am) were unreliable, inaccurate, and definitely not recommended. We had pressure gauges or, better yet, stationary columns of mercury that measured the pressure at which the blood stopped and started flowing through the arteries in the arm. Although it is actually possible for an individual to use one of these manual devices to take his own blood pressure, it was awkward and interfered with reliablility of the measure. Therefore, two people were really needed. A number of years ago, the automatic cuff became more popular. At first, most of these were cumbersome devices that were placed in your local friendly drug store or mall, into which the customer placed a forearm and an electrically driven cuff was tightened until the sensors imbedded in it cut off blood flow, then released the pressure until the flow was restored. For whatever reason, these proved surprisingly unreliable and, no matter how often they were calibrated, they were simply dangeroulsy inaccurate.
Soon thereafter, a plethora of small, home devices that operated on the same principle appeared on the market. These, too, were less than acceptably accurate. But they got better over the years until I finally tested one that seemed to give reliable readings. Well, reliability is one thing; it is possible to be reliably wrong, too, but this wasn’t. It was remarkably in agreement with the readings my wife took with a standard medical cuff. (She was a nurse I met when I was in medical school, and took a mean blood pressure.) This device was made by Omron and is reviewed in these pages (cited below). I bought one and have been using it for years.
The same company put out a small, compact and very easy to use cuff that measured the pressure at the wrist, as opposed to the upper arm. This allowed for greater ease of use and more compact size. I had to have one, but really didn’t expect it to be acceptably accurate. I was wrong. In numerous trials, the Omron 637 performed flawlessly. Its readings were consistent;y correlated with those of the known vslid cuff, although the were consistently a small amount lower in both systolic (the higher number) and diastolic (the lower number). As long as the readings are relaible, any bias can be easily corrected.
The entire front of the device is about two by three inches, most of which is an easy to read screen. The rest of the face comprises buttons for setting, starting and stopping, and controlling the memory and grwaph features. It holds 90 readings in memory and is capable of displaying results in graph form for various periods of time, or times of say. It also has a computer port (USB) to feed the information into your computer foor further analysis. It fits on either wrist, comfortably. It has a one button start and only runs when it is in the proper position, which is signaled by symbols on the screen. When turned on and properlyu positioned, it inflates, fairly quietly humming to iteself and squeezing your wrist until it reaches the levels of blood flow it wishes to read. The whole process takes less than 45 seconds from putting it on to getting your reading. It runs on two AAA batteries that are good for over ninety readings
In other words, this cuff is usefully accurate, small, convenient to use and carry, and not terribly expensive. Depending on various sales it can be picked up for between forty and sixty dollars.
