CardyMeter Question

Just got my Horiba B-731. My readings so far are a lot lower than my Serum readings which are almost always exactly 4.6 (and my EXATEST reading 3 years ago was high-normal) I'm getting readings in the 600's which convert to about 4.0 using this link [hkpp.org] 4 questions: 1) what is the best way to collect a sample - I'm basically spitting into it after I haven't had anything to eat or drink for a little bit 2) what could explain higher blood serum than intercellular readings - I thought it was slightly the opposite. 3) How in the heck does the math work? Why does a reading of 0 mmol/L = 3.0 blood serum 4)How often do I need to calibrate this thing? ( I get strange readings when I clean it or turn it sideways to remove the water I use to clean it) Thanks, Ralph

Question 1 - your method seems OK if the unit is calibrated.

Question 2- The unit does not measure intercellular levels, it measures Saliva levels, which you plug into the online calculator to get a correlated approxiamate value of what your blood serum levels are based on your Saliva readings.

Question 3 - You are talking about a 0 reading on the cardymeter, that is not a 0 mmol/L reading. You stated the question backwards, you are talking about a 0 reading on the Cardymeter, coming out as a "3" mmol/L reading using the Online calcualtor. To try to answer the queston, your not going to get Saliva readings anywhere near 0 anyhow, the conversion methods take into account possible ranges of Saliva K+, not impossible ones.

Question 4 - Calibrate it weekly, or whenever you get a reading that has changed dramatically. If you clean it with a cloth, then there may be K+ in the cloth that spikes the reading. I just used water to rinse it out, I never did try to get it completely dry, as anything you use to dry it could cause K+ comtamination.

AntiFib, If it isn't completely dry, it seems to me it would dilute your saliva and change the reading. Also, re the math, I think a 0 on the Cardymeter means 0 parts per million (the 2000 solution is 2000 parts per million). So how does 0 ppm = 3.0 of anything?

I've wondered the same thing about diluting the Saliva, not sure how to dry the sensor without damaging it. The sensors are expensive to replace. Maybe using some sort of sterile non-abrasive cloth or something. The insruction book says something about it I think.

As for the mmol/L, I guess we need to study up on what a mmol/L is anyhow, I think the mm stands for millimolar and it has to do with measuring the density and mass of solutions.

IN the original Cardymeter ( there blue one that looks like an old cell rectangular small cell phone or thin deck of playing cards) you have to calibrated it more frequently and use a true distilled water to clean the sensor and for a difference fluid for calibration before using a thin piece of absorptive paper with the saliva ,, either coating the paper strip with saliva or putting a piece on your previously a few minutes earlier throughly rinsed and swished out tongue and then using the supplied or at least some very clean tweezers to remove the saliva soaked paper and placing it on the sensor.

Playing close attention to each of these steps, including careful calibration gave me incredibility accurate results when I use to use it frequently in the bad 'ole days of active AFIB. I did 10 separate calibration tests with serum K draws in which I fully calibrated and ran the Cardymeter test just moments literally , under 30 seconds, before the needle drew out the blood specimen for the Serum K reading.

Several of these calibration tests were done in ERs just prior to a Cardioversion and the others were all in NSR done at a regular LabCorp blood lab.

Out of these 10 tests my average variation in the calculated serum equivalent from the Cardymeter reading to the actual serum K reading was an amazing +/- 0.1 variation average!! A few of these test were spot on the same number as the Serum K reading.

And I am not alone in this degree of accuracy but with many of the periodic paralysis group and one or two folks here as well got similar spot on accuracy with the original meter, although with a bit more fuss required to insure such accuracy.

What I am not sure is if the new model which is said to be improved truly does achieve similar consistent results as the old one. Not requiring such frequent and at times tedious calibration as the old one 'may' have been achieved at a more rounding off of the accuracy range. Though I am not sure.

It doesn't have to be spot on as long as it consistently tells a consistent story the is the same story told by Serum K as well. IN other
words are you too far below or above the sweet spot of 4.2 - 4.9 Serum K range to help foster a stable heart?

Shannon

What I am thinking is that my readings may not precise, but it does'nt matter in my case because my issue with low or high K+ is resolved by boosting my IC Mg levels, which as I understand it, transports the electrolytes in and out of the cardiac cells. So now I am focusing on Mg, not K+, and am thinking about how to take my first Mg bath.

Gentlefolk,

I have had two other people look at the B 731 instruction book and we can't make sense of it.

I put in saliva and the display said 1700

But what we couldn't work out is what to do next.

The others are a bit young for Alzheimer's

Thanks

Alex

Alex,

Caveat - I don't own one of these. But here goes - you need to go through the conversion from the saliva reading to the serum K reading. Put your meter reading in here: <[hkpp.org] You can also use this chart <[drive.google.com]

For the chart, take the meter reading & multiply by 0.026. In your case 1700 x 0.026 = 44.2. Then go into the chart. 44.2 is equivalent to 5.8 mmol/l (or high!) Putting 1700 in the calculator gets 5.76

George

Hello George,

Thanks for your reply .It made my life easier.I am a lazy person in some ways !

Is being a touch high ok or better to reduce a little ?

Alex