Lab Tests vs Finger Poke?

[kerri73]

I'm just curious if anyone thinks the finger poke machines read any differently than the full fledged lab draws... I can't imagine it would be a whole lot, but I've been on track forever until I switched to this new doctor, and they do regular lab tests at the hospital... and my dose has had to be raised quite a bit (it could just be my body lately and I would guess eventually it will have to be lowered again). I used to be on 7.5mg 3x a week and 5mg the rest for *ever*... now I'm up to 7.5mg 5x a week and 5mg 2x. Just interesting is all - and could just be coincidental timing, too!

Thanks in advance!
Kerri

 

[Ross]

You can't really compare the two. Lab uses different reagents on whole veinous blood and the machines also use different reagents on capillary blood. There will be a difference, but should not exceed .6 between the two.

Our bodies do some weird things with little to no explaination sometimes. Your not ingesting any hidden sources of vit k such as carnation instant breakfasts or boost or ensure, health bars?

 

[kerri73]

No bars or anything like that - I'm usually pretty good about watching what I eat. And I'm usually consistently against eating salads. I'll have to pay attention to what I'm eating and see where it goes from here!

Thanks Ross!
Kerri

 

[njean]

I'm just curious if anyone thinks the finger poke machines read any differently than the full fledged lab draws... I can't imagine it would be a whole lot, but I've been on track forever until I switched to this new doctor, and they do regular lab tests at the hospital... and my dose has had to be raised quite a bit (it could just be my body lately and I would guess eventually it will have to be lowered again). I used to be on 7.5mg 3x a week and 5mg the rest for *ever*... now I'm up to 7.5mg 5x a week and 5mg 2x. Just interesting is all - and could just be coincidental timing, too!

Thanks in advance!
Kerri

Kerri,

Sometimes our INR levels changed according to our activity levels. I find that when my activity increases, I require more coumadin. Now, for others, this may be just the opposite but that's the way it works for me. I have been on coumadin for many, many years & I know my body better than even the doctors know.

Your diet may play a role in it but you should not have to go without eating the foods you love, like salads for example. Foods high in Vit K of course you yourself need to avoid as Ross mentioned in his post.

Anyway, I wouldn't stress out about it; just adjust your coumadin according to your INR & get on with it.

P.S. I had been on 7.5 twice a week for the past 2 months or so & now I'm having to take 10mg per day. I also have a home monitor & I test every week.

 

[JimL]

I had an opportunity to compare the two a few weeks ago. I had a veinous draw, got the INR results (high) and then stopped into the coumadin clinic where I usually go. The nurse there did the finger poke just to reassure me, and the INR was .1 different from the lab draw, still high. There was less than 90 minutes between the two tests.

 

[catwoman]

Kerri:

One thing: Do you take a multipurpose vitamin? Have you bought a new bottle lately?

I was at Walmart yesterday to buy more vitamins, and found that the Equate brand has added Vitamin K. I examined every single bottle of every kind of multipurpose vitamin in the store and found that only the One-A-Day brand for cholesterol and some children's formulas have NO vitamin K.
Everything else now has vitamin K.

Which means, I either buy a kid's vitamin or buy the "new & improved" Equate product I've bought for 12+ months and know I'll have to adjust my dosage.

I eat a lot of vitamin K as it is. I guess "normal" people don't.

Maybe vitamin makers are in cahoots with the manufacturers of Coumadin and the generics.

 

[dick0236]

Catwoman: If you have Kroger in TX look for their store brand One Daily Essential. I was referred to that by my cardio. It has no vit K.

Kerri: If my math is correct, they have bumped you up 2.5mg 2X per week. Thats a little over +10% and I would assume they are trying to raise your INR about .5 to .8. From your profile you have been on coumadin or warfarin for quite awhile and you are aware that INR does change for NO apparent reason. The biggest problem that I have had in changing docs over the years is for the new doc to overreact and get me on a "yo-yo".

 

[Natanni]

My husband has had lab draws within a half hour of his INRatio testing, and it has always been +/- .5. We can relate to dosage changing-his coumadin clinic only believed in giving out 5 mg tablets and dosing according to how you can split them up (and that is what their computer program is set up for!). Since August of 2007, they have been scaling him up to 45 mg per week (INR 4.8 and climbing) down to 42.50 mg per week (1.7 and decending) until we went back to the MD and begged for 2.5 mg tables to break in half, finally giving him 43.75 mg per week (YAY! back in range FINALLY 2.8 !!) OUr diet had remained exactly the same. He did quit Zetia around that time. We were told it could be the cold weather and stress could be accounting for the changes. After 2 years of being in range we were pretty shocked at dose change too!

 

[Philip B]

INR & Testing

INR & Testing

I had differences in my lab tests and test results from my home monitor. The differences really puzzled me and had me questioning the accuracy of my monitor. When other members explained how differences can occur in lab tests I stopped worrying about differences between my monitor and what the lab said.

Advice commonly given here involves making sure that you dose your diet rather than trying to control your coumadin dose with your diet. Eat what you want and adjust your dosage to keep yourself within your range.

-Philip

 

[catwoman]

Catwoman: If you have Kroger in TX look for their store brand One Daily Essential. I was referred to that by my cardio. It has no vit K.

Found 'em. And Kroger's had a buy 1, get 1 free deal. I have enough vitamins for about 18-19 months now.