A question from allison: 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?
Best answer:
Answer by steve
the cuff is probably too small. try buying a larger cuff that is compatible with your monitor.
What do you think? Leave you answer below!
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.
Check the batteries. Check the cuff is in the right position and the tube is centered in the middle of inner elbow, the cuff is on tight but not too tight. Check to make sure tube is plugged into monitor. Cuff may not have been deflated enough before starting the monitor.
the monitor might need replacement. contact the company from which you purchased it.
Here it is in a nut shell.
You may take blood pressure readings every day- but just how accurate are your findings? Make sure you meet American Heart Association standards for this key assessment procedure by reviewing the guidelines here.
The equipment…
Errors can arise from uncalibrated or damaged equipment or from using the wrong equipment. (See Check for Problems before They Start.) Mercury manometers, for example, can yield inaccurate readings if the air vent at the top of the column is clogged or the mercury has oxidized. You may not spot these problems by looking at the manometer, but suspect them if the mercury column responds sluggishly. To prevent these problems, find out whether your institution has a written policy for regular assessment and maintenance of mercury manometers – and make sure to follow it.
With aneroid manometers, check before each use that the needle is on zero at baseline. If it isn’t, recalibrate it to a mercury manometer using a Y connector attached to the tubing on both manometers. Compare pressures at several points along the scale. As with mercury mamometers, be sure this equipment is monitored and maintained regularly.
Incorrect cuff size is a major source of equipment-related errors. A cuff that’s too small will produce a falsely high reading; one that’s too large, a falsely low reading.
Using the wrong-size cuff is a common problem with obese patients. Taken with a regular cuff, their systolic and diastolic pressures will be falsely elevated. A similar potential for error exists for patients with extremely thin arms- for them, a regular-size cuff may be too big, leading to falsely low blood pressure readings.
To check for proper cuff size, the American Heart Association recommends comparing the cuff with your patient’s arm. The length of the bladder should be at least 80% of the arm’s circumference. (See Using the Right Cuff.)
The stethoscope you use for auscultation should have a shallow bell with a large diameter. This lets you auscultate low-frequency sounds. (See What You’re Measuring Isn’t What You’re hearing.)
Most nurses use the diaphragm of the stethoscope, but you should use the bell to auscultate indirect arterial blood pressures. Don’t put too much pressure on the bell; you may occlude arterial flow and dampen out the low frequencies.
…the patient…
As you know, using too small a cuff to measure an obese person’s blood pressure can cause a falsely elevated reading. You can also get a falsely high reading with a patient who has a peripheral edema-even if you use the right equipment. Like obesity, peripheral edema can diminish sound transmission, so avoid using edematous limbs to take blood pressure when possible.
Talking can also produce a falsely high measurement, as can pain, anxiety, or discomfort. Conversely, peripheral vasoconstriction, brought on by cold temperatures or vasopressors, decreases blood flow and can cause a falsely low reading.
Failing to support the patient’s arm, which causes isometric muscle contraction, can also lead to false measurements. So be sure the patient’s arm is supported and positioned at the level of his heart. Otherwise, hydrostatic and gravitational forces within the blood vessel will produce a false reading: If his arm is above heart level, you’ll get a low reading; if it’s below heart level, you’ll get a high one.
In short, the more rested and relaxed your patient is while you’re taking a reading, the more reliable your measurement will be.
…and you
The last major source of blood pressure error is the person taking the measurement. And in most instances, the problem is incorrect technique. (See 12 Steps to Taking Accurate Measurements.)
To ensure an accurate reading, position a mercury manometer with the meniscus at eye level and an aneroid manometer in your direct line of sight. To hear soft sounds that you might otherwise miss, deflate the cuff slowly.
Taking a patient’s blood pressure correctly requires keeping your eye not just on the manometer but on the rest of the equipment, the patient, and yourself as well. If you do, your efforts will translate into more effective practice for you and better care for your patient.
I hope this info has helped you, take care….