? Alphatrak vs Alphatrak 2 vs Freestyle: strips and codes

I have finally received "my" new AT2 in the post, so I'm going to be able to give my vet his AT back. I've also ordered Freestyle strips that I've received.

I found a 2012 thread on the canine forum saying that the code 7 should always be used with the old AT meter. But have things changed since then? I've been inputing the "proper" code in the AT (that I've been using until now).

The freestyle lite strips come with a 16 code on them. But should I use the code? Another code? I know using the wrong code doesn't change that much, but how much? Does anybody know, or has anybody fooled around with codes on the AT to see what difference it really makes?

(And I feel a bit silly worrying about all this when I know there is a 15-20% error tolerance on these machines...)

 

Same drop of blood. Code 8 for AT2 and 37 for AT.

 

For science, I wasted some strips. Measurements in order.

blood drop 1:
AT2 code 08: 5.9
AT code 37 (code on strip box): 4.8
AT code 07 ("incorrect?" code): 6.2 6.7

blood drop 2:
AT code 07 ("incorrect?" code): 6.4
AT code 37 (code on strip box): 4.9

Previous reading was:
AT code 37: 4.3
AT2 code 08: 5.4

 

Yes, things have changed. With the AT2 meter, use the code on the last vial of proper AT strips you had. There are about 6 different code numbers that appear on those vials. Ignore the FS Lite code number.

We always suggest doing a few same drop comparisons whenever you start a new vial of FS strips in the AT2 meter. At some point you just have to go for it because you could drive yourself nuts doing these.

 

THe code one inputs would depend (BUT NOT BE THE SAME AS) upon the code on the FreeStyle strip vial. For human meters the code is used to account for the different properties of lots of test strips. For pets, the code entered accounts for the previous and also the fact that the glucose distribution in the blood constituents is different between human and cat blood.

Blood has two constituents, the red and white blood cells and the liquid (serum). Blood plasma is blood serum without the clotting factor

The blood glucose value obtained via laboratory analysis is the glucose level in the serum/plasma constituents of blood

The glucose is in both the serum and red-blood cells (RBC) themselves. However, the distribution of glucose is different between humans and cats (and dog too)1
In Humans 58% is in plasma/serum and 42% in RBCs
In cats 93% is in plasma/serum and 7% in RBCs
In dogs 87.5 % in plasma/serum and 12.5% in RBCs.

 

@Larry and Kitties thanks! Yep I'd seen the different distribution of glucose between plasma/serum.

Now, regarding my FS strips, does that mean I could calibrate them myself with the test solution? I've seen with the AT ones that having the code change from 8 to 38 does make quite a bit of a difference. Is the code simply a kind of "incremental" correction that is applied to the reading? Is it linear?

 

Yes, best would be to use the test solution and the change the code so it best matches the value on the test solution vial.

 

the code for AT2 meter with freestyle lite strips that i have found to be the closest with the AT2 strips readings is #38, it is always less than 10 points difference and often around 4-5 points or better compared to the AT strips readings that are set on code 37 or 38 when BG is under 100 and up to about 120 (i don't know what that computes to for your country but, it is dark greens/low blues). the other AT codes i tried/used with freestyle strips were always off by more and not very consistent with the AT2 strips results the majority of the time..

As for calibrating the FS with AT solution, IMO that just shows the strips are in right range but, does not show which code is given you the best readings. After first trying solution, i decided using the AT strip BG results to determine if FS strips in new vials are reading right/close is best. nowadays, i just use same blood drop and do double BG readings with last FS strip and new FS strip when i am on my last strip in a vial. have had no issues doing it this way but, sometimes i will still double check with the more reliable AT strips.

 

I keep forgetting which members told me this but I was told it is not advisable to use the FSLite test strips with the AT2 meter anymore. The companies have changed so it is not recommended. It was after that was mentioned to me that I went & got a FSLite meter and no longer use my AT2 meter. Sorry I don't remember who that was so I cannot tag them for their input.

 

The test solution will work fine for determining a code that works. It is really same as testing blood with regards to a BG value nd it does not change like different drops of blood can.
I would use solution on AT strip and not note value. Then use the FS strips and try codes so you get close the value measure with the AT strip.