How long has it been that we've been taking blood pressure (BP) readings? About 200 years or so, I think, which is also, I believe, even longer than Regis has been on television. So given that we've been at it for so long, you'd think that we would never err in taking BP readings. This is not rocket science, after all. All that's involved in taking a BP reading is that a cuff is tied around someone's limb (most often an arm), the cuff is inflated so that the pressure shuts the artery in that limb. As the pressure is released, the BP reader records the point at which a sound appears as blood re-enters the artery (systolic reading), and the point at which the sound disappears or muffles (diastolic reading). This is so easy that if you had the time and money for the training, you could replace health professionals with apes to do BP readings (no obvious jokes here, please), and that the apes would still get it right every time.
If they did get it right most of the time, however, the news is that the apes would be way ahead of health professionals because according to a study presented at a meeting of the American Society of Hypertension, a significant proportion of BP readings are wrong, most often on the low side.
How can things go awry? Lots of ways. For a start, we've long known that errors occur when a patient is not relaxed enough, when the BP cuff is not the right size (bigger arms need bigger cuffs, something I'm sure they teach all cops in cop school), or even when the BP reading is taken with the patient sitting rather than lying down.
But this study found that inadequate equipment also plays a key role in BP reading errors. You see, unlike the old "mercury-in-the-glass-tube" blood pressure measuring devices that were the standard until a few decades ago and which were virtually foolproof, the new aneroid devices now used in most medical offices must be re-calibrated regularly because there is no way to tell if and when they have stopped working properly, and according to this study, up to one-third of aneroid devices have not been re-calibrated and are not working properly, and these devices, say the researchers, give misleadingly low BP readings. In other words, lots of you have been told your BP is OK when it may actually be high.
Well, now that I've made you all doubt your BP reading, let me destroy your faith in yet another procedure your doctor commonly does on you. Did you know that . . . Hey! Relax! I can smell your fear. So I'll simply save that for the future, OK?