isi of 1 coming for Coaguchek

Marty · Dec 4, 2003

I have a Coaguchek that has served me well for five years. Its been dropped, frozen, and overheated in the trunk of my car and nothing seems to bother it. Its based on a simple principle. The thromboplastin on the test strip is impregnated with little bits of iron. On either side of the test strip there are magnets of alternating polarity. Put a drop of blood on and the iron filings wiggle till the clot forms. When they stop wiggling thats the prothrombin time.The main draw back of the Coaguchek has been
its thromboplastin which has a sensitivity (isi) close to 2. Since the prothrombin ratio(patient PT over control PT) is sqared by the exponent equal to the isi it makes the coaguchek nonlinear and less accurate at the higher levels. Do the math.
Well when I ordered my strips from Indianapolis today I was told by one of the techies at Roche that Coaguchek strips with an isi of 1 are in the pipeline and will probably be ready in 2004. A good monitor will become even better.

LUVMyBirman · Dec 4, 2003

Hi Marty!

Thanks so much for the news! Can't wait.

It's all in the strip correct? No changes to the unit itself? Have an 'original' and would like to keep it

.

Hope all is going well for yourself and Alice. Is she still on the Coumadin?

Happy holidays!

Marty · Dec 5, 2003

RE: ISI=1

RE: ISI=1

Hi Gina, We are happy to hear you are all doing well.
Yes, the isi change is all in the test strip and the chip that comes with the strips. It will work with both the old and the new monitors. Alice has a floppy mitral valve but not enough regurg that needs surgery. The valve is most likely the cause of her fibrillation but she has been in sinus rythym for many months now since undergoing cardioversion.She no longer has to take Coumadin. They have her on a powerful antiarrythmic called Betapace. It is like amiodarone and not everybody can tolerate it, but Alice can with no obvious side effects.We wish you a VERY happy holiday!

catwoman · Dec 5, 2003

Marty:

Does this mean that people with ProTimes will find their PTs more in line with that on a CoaguChek? ProTiime's isi is 1 now.

I just got a ProTime, am to take it to my PCP next Thursday a.m. for a double test.

Marty · Dec 5, 2003

ISI=1

ISI=1

Yes, Marsha, We think it should help in this regard. Going from seconds to INR can cause a lot of variation if all the isi's are
different.

Guest · Dec 8, 2003

Thanks for the update, Marty.

I think that they got behind on this new strip after they had the recall.

Cat... the biggest difference will be when an INR is out of range. The higher the INR, the less accurate it is with Coagu Chek. It makes little difference when things are in, or close too the range.