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Blood Pressure Monitor Hem 712c

[mage source="flickr"]Blood Pressure Monitor Hem 712c[/mage]
why do I get error on my blood pressure monitor?

I have an Omrom HEM-712C bllod pressure monitor in my home and often I get an error message. Why?

You get an error message because the monitor operates by recording the cuff-pressure when certain audible signals (Korotkoff sounds) are recognized by the internal microphone, and are registered as 'Systolic' and 'Diastolic'. That is, isn't actually measuring your arterial pressure at all, ... just the cuff pressures when the noises first come and then disappear. Doctors think these are true pressures, but of course, when you think about it, they aren't, and couldn't possibly be, could they....

However, for the Korotkoff sounds to be recognized they have to be of a certain audible pattern (in the same sort of way that -for instance, you could recognize a man's shout from a woman's scream.. or a dog's yelp.) - The analyzing filters forming the electronic devices inside the monitor must be able to distinguish these.
Usually they can, but under certain conditions the way the blood stops flowing and starts again as the cuff is pressurized and then deflated, the noises themselves are too indistinct for the machine to register.
That's all it is. There's not much wrong with the machine, but obviously there are cheap ones and expensive ones.. Presumably the cheap ones don't work as well (but knowing manufacturers and the medical industry, don't bet on it! - Where there's $$'s to be made, be sure they'll make them !)

Better by far to get hold of a used stethoscope and use it yourself to listen to the sounds yourself. It's really very simple, although every possible obstacle will be put in your way to prevent you "learning the tricks of the Trade" .. but honestly, -it's a doddle, and you''ll learn it v. quickly.
If it's any comfort to you, my wife gets an error message 9 times out of 10 with an Omron, but it always registers mine very happily. So she's taken to using a wrist-monitor instead and gets along fine with it. I calibrate it for her with a proper sphygmo and there's no problem

PS The size of the cuff has absolutely nowt to do with it.. please don't waste your money on buying another one. Why? Well, - if you did, you'd get the same number of error-messages, but worse still you'd find that the readings you DID succeed in getting on the machine with the two different cuffs wouldn't agree with each other! That's why.