Coaguchek INRange ...

[pellicle]

Hi

I think your plan is good ... I'm going to make a prediction here and it will be interesting to see if I'm wrong. Since the INR reading is done by the strips and not the machine (which I understand to be nothing more than a simple counter timer) that the XS machine and the INRange machine will give almost the same reading.

I love a good bet.

Myself I would not want an INRange because I don't like all that fancy delicate tech in a thing that essentially only gives graphs for people too lazy to chart their own in a spreadsheet.

http://cjeastwd.blogspot.com/2017/01/2016-inr-data.html
Meanwhile my XS has travelled extensively (Australia <> Finland <> Sweden <> UK ...)

One question: which of the out of range value for INR is better ( ), the higher one or the lower one (i.e. 2.0 or 4.0 with therapeutic range of 2.5-3.5)

from "Optimal level of oral anticoagulant therapy for the prevention of arterial thrombosis in patients with mechanical heart valve prostheses, atrial fibrillation, or myocardial infarction: a prospective study of 4202 patients."
http://jamanetwork.com/journals/jamainternalmedicine/fullarticle/415179we see this graph

there are essentially two risks represented here

1. clot risks
2. bleed risks

you can see clearly that the risk does not really go up much on the higher side (the bleed risk side) until INR>5.5 however the clot risk goes up steeply for INR < 2

 

[bece13]

Haha, exactly my bet. XS and INRange will show the same thing. Will see.

I'm with you, the graph is useless for me, I only care for raw data. Unfortunately they told me that the XS was discontinued in Canada and INRange is the follower. Don't know if it's true or just PR.

I think I saw those graphs and tables, but failed to analyze them properly. My bad. I guess I have to go back to your blog and re-read your posts.

Does it make any sense to split the daily dosage and take half in the morning and half at night? for me will be easier as I take Metoprolol twice a day. (morning and night) this way I'll take the same pills in the morning and at night. I have to start using my pill box...

 

[pellicle]

Hi

Does it make any sense to split the daily dosage and take half in the morning and half at night?

no, because the half life of the drug is over two days ... this is how warfarin builds in your system (approximately) each day from commencement

I have to start using my pill box...

you DO ... here are my rules

• use a pill box to ensure that you can visually see if you took them
• have an alarm on the phone to remind you (because distractions happen)
• leave it in a place where you'll be able to see if you took them or not

I take mine in the PM and so when I take my AM pills (antibiotics for my mysterious friend and some metalic ions) I can see if I did a whoopsie the night before ...

Best wishes

 

[bece13]

Hmmm... I understand that the half life of warfarin is 2 days, but in the and you end up with the same build up of warfarin in your body in both cases.

Anyhow, your point that you can see if you missed your previous night dose in the morning is a good failsafe.

Thanks

 

[pellicle]

Hmmm... I understand that the half life of warfarin is 2 days, but in the and you end up with the same build up of warfarin in your body in both cases.

perhaps I misunderstood your meaning with question " Does it make any sense to split the daily dosage and take half in the morning and half at night? "

So if the half life is as I said what would be the sense of it? some attempt at harm minimisation with forgotten doses?? There is already no harm with a missed dose as long as you take it the next day with the other (or even in the other half of the day cycle when you notice it)?

 

[bece13]

I guess my formulation was bad. Was thinking of convenience on my side to have the same quantity of pills in the morning and at night. But I like your failsafe more.

 

[pellicle]

its unimportant in the longer term (over a week) ... an important rule is don't attempt to micromanage warfarin

 

[pellicle]

onvenience on my side to have the same quantity of pills in the morning and at night.

given that they are so small what difference does it make to take 3 tiny pills in the (say) PM and only one in the AM?

its not a lot to swallow

 

[pellicle]

My only concern here is that the testing lab where they analyze the blood sample is about 100km from their local lab where they only draw blood. I usually get the results in about 8 hours.

as long as the blood is centrifuged prior to transport it shouldn't be an issue.

https://www.geisingermedicallabs.com/catalog/details.cfm?tid=1406

SPECIMEN PROCESSING
Specimen processing instructions:​	If specimen will be analyzed within 24 hours: Whole blood can be submitted. If specimen will be analyzed after 24 hours: Centrifuge the citrated blue-top tubes at designated speed and time to obtain platelet-poor plasma (<10,000/µL). Using a plastic pipette, remove 1 mL of plasma and transfer to a plastic aliquot tube and label with patient's name and a second patient identifier (e.g., date of birth, medical record number).
Transport temperature:​	If analyzed within 24 hours, store and transport whole blood at room temperature. If specimen analysis will be beyond 24 hours, remove plasma and freeze. Transport frozen.
Specimen stability:​	Whole blood: 24 hours at room temperature. Plasma: -20°C for 30 days, -70°C for 6 months.
Rejection criteria:​	Clotted, overfilled or underfilled tubes. Stability limits exceeded. HCT >55. HCT > 55 requires rejection, reorder in LIS, and recollection with proper adjustment of anticoagulant.

However centrifuge time does have an effect

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369063/
This should be well understood and is about 30 year old processing concepts.

 

[bece13]

True.
Here is my chart so far.
X-axis is number of days since surgery
Left Y-axis INR and Warfarin daily dosage (mg)
Right Y-axis is Warfarin Buildup (mg)

Ignore the the first 15 days as that I was getting boosters in my belly in some days and don't know the values.

 

[bece13]

Don't know why was posted twice... fixed it now ...

 

[pellicle]

True.
Here is my chart so far.
X-axis is number of days since surgery
Left Y-axis INR and Warfarin daily dosage (mg)
Right Y-axis is Warfarin Buildup (mg)

interesting, how are you calculating the warfarin build up (accumulation)

feel free to reach out to discuss this topic

 

[bece13]

here is the graph, just could't send it in pm...

 

[ATHENS1964]

Today I did a test in the lab to check the inrange the lab showed 2.9 and the roche 3.3
My goal is 2.00 to 3.00,

 

[bece13]

So Pellicle was right : CoaguChek XS and Coaguchek INRange - same result

Today's test:
LifeLabs - 2.6
Pharmacy using Coaguchek XS - 3.6
My device Coaguchek INRange - 3.6

So far differences between this Lab and Coaguchek are consistent between 0.8-1.0 (5 tests done)

Next step: in 1-2 weeks to check against another lab after I talk to my Family Physician.
Maybe I have some kind of condition that I'm not aware that influences the readings...

 

[Dodgy Ticker]

Hi all

When I got my Coagucheck here in France, the hospital properly calibrated it before handing it over. I don't know HOW they did it, but it might be worth checking whether you can ensure it is calibrated.

Secondly, my heartfelt advise would be to not go crazy fretting about these variances. In truth there IS margin of error, but there is also a good margin of variance between when a variation is noticed, and when it has a noticeable impact - death would be a pretty good sign, I reckon !! hahaha....

I have had utterly wild swings, and I kid you not - I even had an INR of 11 last year after an idiot doctor prescribed morphine for an attack of sciatica.

I am pleased to report - I'm still here !!!!

So keep an eye - yes, but don't fret too much.

Good luck to you - and everyone else having to put-up with this life-long crap.

 

[LondonAndy]

Hi all

When I got my Coagucheck here in France, the hospital properly calibrated it before handing it over. I don't know HOW they did it, but it might be worth checking whether you can ensure it is calibrated.

Secondly, my heartfelt advise would be to not go crazy fretting about these variances. In truth there IS margin of error, but there is also a good margin of variance between when a variation is noticed, and when it has a noticeable impact - death would be a pretty good sign, I reckon !! hahaha....

I have had utterly wild swings, and I kid you not - I even had an INR of 11 last year after an idiot doctor prescribed morphine for an attack of sciatica.

I am pleased to report - I'm still here !!!!

So keep an eye - yes, but don't fret too much.

Good luck to you - and everyone else having to put-up with this life-long crap.

I don't believe that there is any adjustment hospitals can do to the CoaguChek machines, but I wonder if the issue is one of language: my hospital anticoagulation clinic in London used to refer to the six-monthly visits as "calibration checks" for my meter, but actually all they were doing was comparing the result from my machine with the result from theirs. I wonder if it is making a process sound more impressive than it actually is, for the benefit of us mere mortals.

However, I agree with your other points!

 

[bece13]

Thanks Ticker and Andy for responding.

Talking to Roche, they said the devices are calibrated from factory and cannot be recalibrated. You can only check with test solutions that is accurate (which in my case it is) They raised my case with their Global support and are waiting for an answer. In the meantime they will try to call LifeLabs to see what kind of reagent they are using. They said that Coaguchek is using human reagent for thromboplastin and they have multiple quality control checks build into the strips. IF Lifelabs is using animal reagent for Thromboplastin, this could explain the difference. Not sure if is BS or not at this point. Also they said that Coaguchek might show a bit higher readings (0.1-0.2) than true INR value.
I talked to my Family Physician and next week I will compare LifeLabs to a different lab (Dynacare). I will keep everyone posted on the results.

At this point I'm not too concern as I'm more or less inside my therapeutic range of 2.5-3.5 but would like to to know which is my true INR value.

 

[pellicle]

I talked to my Family Physician and next week I will compare LifeLabs to a different lab (Dynacare). I will keep everyone posted on the results.

Good plan

 

[bece13]

Another test done yesterday:

Lab -> LifeLabs - 2.8
Lab -> DynaCare -2.6
My device -> Coaguchek INRange - 3.6

Conclusion: 2 Labs got approximately the same reading and a difference of 0.8-1.0 compared to Couguchek XS (pharmacy) or Coaguchek INRange (my device)

Talked to Roche again and they don't have any explanation and said that Coguchek might just not work for me.

Looks like I hit a dead end. I will set my INR target to 2.8 with the Labs and 3.6 on my Coaguchek INRange and continue to monitor weekly with my device and do a monthly check with the Labs. (my recommended therapeutic range is 2.5-3.5)