differences in meters? so frustrated!!

[girlunravelled]

i couldn't figure out why i was getting SUCH a drastic difference between my home tests and my vet's tests. i knew some of the higher numbers could be attributed to Cully being stressed, but not 150 points of difference!

tonight, a friend gifted me with a Beyer Contour meter (I've been using a True2go). I tested mine on both and there was a 20 point difference, which since I'm not diabetic, is a very strange difference. Then I tested kitty's. On the old meter, BG was 199. On the new meter, 369!!!!!! :shock: :shock:

Needless to say, this explains a lot about why Cully's been so off the last couple of weeks. I thought maybe the Lantus had pooped out (I got a whole new prescription for it), but now I'm thinking I just wasn't getting an accurate reading. He's lost another pound in the last month despite bolting down all of his food and is drinking almost 10oz of water a day.

fingers crossed that the damage hasn't been too severe. The doctor has had me up the Lantus to 1.5 units, so hopefully that helps.

And I'm back to testing his blood sugar every day.

Poor kitty. :cry:

 

[Sienne and Gabby (GA)]

The True2Go meters have not had such a good track record.

A couple of issues to keep in mind. Unless your vet is using a human meter in the office, the glucometers or serum chemistry analyzers that are typically used in the vet's office are calibrated for an animal. There is often a 30 point difference between your Contour and the vet's meter with the vet's meter running higher.

There is also a 20% variance in numbers that is typical with any meter. So when you see any number, if you think of it as a range, that will be more accurate.

 

[girlunravelled]

thank you so much for that info!

I'll check with my vet tomorrow morning, since I'll be calling him to tell him about the new numbers. I'll check to see what type of glucometer they use there.

And it's good to know about the 20% variance. I'll absolutely keep that in mind going forward!!!

:smile:

 

[Phoebe_TiggyGA_NortonGA]

I have found that all meters with TRUE in the name are poor

 

[BJM]

Lots of folk stumble across that issue.

The FDA decided that being within 20% of the 'true' value was good enough for you to make decisions about diabetes control.

value -> actual range
100 -> 80 - 120
200 -> 160 - 240
300 -> 240 - 360
and so on

 

[Gina & Yittle (GA)]

In the early days of Yittle's diagnosis he could quite easily spike 150-200 points from a vet visit. I'd take his blood immediately before we'd go. She'd take it there and it would be tons higher. I'd take it when we got back home and it would be consistant with the vet's numbers. 1/2 hour and a few cuddles later he'd be back down to what he was before the visit.

 

[Vyktors Mum]

I was using the freestyle lite meter which tested 72 lower than the vets meter at the same time. So I got a new meter and double tested a few times. I found that the discrepancies got worse the higher his BG was. When the new meter read 455 the freestyle was only reading 280.

 

[MikeysMom]

When you compared meters at the vet, did you use blood directly from the cat, or did the vet draw blood and you tested it from a vial? We did the latter a few times and had a huge discrepancy. Coincidentally, we tried an ear test at one visit...and the numbers lined up, but much higher than the numbers from the drawn blood. We've tried again a couple other times, and got the same thing...a big discrepancy with blood in a vial and very close numbers on blood from the ear. My vet thinks it's because the vials have an anticoagulant in them that affects the human-calibrated meters especially, as they are meant to be used with pure plasma. So if you were testing on drawn blood, it could explain some of the difference.

 

[julie & punkin (ga)]

looking at the numbers BJM posted, what you can see is that a 20% variance is much larger in higher numbers than in lower numbers. we've talked about the issue on here and realize that while it is disconcerting, what we are most concerned about is a cat going hypoglycemic. in the lower numbers, the variance between meters is much smaller.

if you're using lantus, dosing decisions are made on the lowest point of each cycle. so . . . although some of those meters (true brands) are less reliable, among the pretty reliable ones people use it probably isn't all that important.

in general, most of us pick a meter from among the reliable brands and just stick to it. you can make yourself crazy trying to compare between meters.