Hospital Video

[Protimenow]

I was in the hospital for almost the last two weeks. I got bored, so I watched a video that the hospital provided for patients.

The video was about anticoagulation, and, not surprisingly, there were a number of errors:

They showed a 7 day pill box - with dosages alternating from one day to the other. One dose was probably Monday, Wednesday, Friday, with another dose for the other days in the week. All of us experts on this site know that it's better to have the same dose daily - tests are more accurate whenever you test your INR, and your INR stays more level throughout the week.

A more glaring error was that 'if your INR is stable, some doctors recommend testing every 4 - 6 weeks.' This is patently wrong - weekly testing is the best prevention against stroke (and, in remote cases, excessive bleeding). 4-6 weeks between tests is irresponsible.

Getting tired of the crap that this video contained, I couldn't stand any more and stopped watching after 15 minutes.

 

[dick0236]

........A more glaring error was that 'if your INR is stable, some doctors recommend testing every 4 - 6 weeks.' This is patently wrong - weekly testing is the best prevention against stroke (and, in remote cases, excessive bleeding). 4-6 weeks between tests is irresponsible.

Unfortunately, this is a "throwback" to an earlier time when INR testing was by vein draw and lab testing only......and it was a pain in the ass.....going into the docs office, waiting in the "waiting room" for my time, getting a vein draw, and waiting a couple days for results...............and we often had "funny" INR swings between monthly tests. Nowadays, with the convenience of a ten minute home test, I am seldom surprised by my INR........and I perform my test in my shorts......with coffee in hand.

 

[Protimenow]

What surprises me about INR is the difference between meter and lab. I was in the hospital for two weeks, and the first test result was 4.9. The day before the hospital's test, my INR at home was 3.0 I've had issues with large differences between lab and meter, and I'm inclined to trust the meter.

I'd like to get to the bottom of it soon -- if I had some CoaguChek XS strips, I can validate the results with two different meters but, unfortunately, I don't yet have the budget for the strips.

 

[PeterII]

LAB and Coagucheck results will not necessarily match, if you call ROCHE ( they are very good ) they will say that best thing to do is stick to one method of testing because most likely will differ between lab and cxs, Me, i have been doing this for 5 years now, i use regularly coaguchek and once a month or 45 days, i go to lab, simply because blood tests are free for me; and there is always a diff of 0.1 to 0.3 INR; To give myself peace of mind, i aim to keep my INR around 2.5, since my valve is On-X and the range is 1.5-2 according to FDA, i am safe at any value above 2; so if, XS says 2.2 and LAB says 2, no matter, all is fine; I am not recommending this, just sharing what works "for me", also i take 1 asa 81 day; and Vitamin C-500, one thing balances the other; and per dosage, some times i take 3/3/2.5 others 3/2.5/3/2.5, depends on how close to 2.0 INR the test is; and i test every 10 days, Just sharing.

 

[Protimenow]

You should be testing weekly.

I've been self-testing for more than a decade. There was a period when I was testing multiple meters - against each other, and against the labs. I also tested against the Hemochron meters used by my clinic. Lab results at the clinic were about 0 to .4 different from my meters most of the time. I found that the CoaguChek XS was often slightly higher than the clinic/lab, with the difference increasing as the INR rose above 3.0. I found that the Coag-Sense was sometimes .2 or so below the lab/clinic result. Both were within a reasonable degree of accuracy.

The hospital and labs over the last year or so weren't just .2 or .3 from my meter (a value within 20% is okay) - the differences were more than 1 - in some cases as much as 3 higher. This isn't a matter of 'close,' it's a matter of major differences.

Also - if possible, take the same dose daily. If your dose is different every other day, your INR will also show differences from day to day. The best way to get a stable INR, from day to day, is to take the same dose every day. Warfarin is available in a wide range of doses - you should be able to divide your total weekly dose by seven, and use this average as your daily dose.

 

[PeterII]

We are all different, there are only guidelines, but what works works.

My doctor , just to share, says is only required to test every 2 weeks,
so i do it every 10 days, as you can see, i dont do weekly nor 2 weeks,
i do what works "for me"

We are all different, absolutes are not real.

Just a thoguht

 

[Protimenow]

Personally, I wouldn't truxt many doctors to know much about anticoagulation management.. They may be using outdated guidelines that don't accurately apply to more recent recommendations and protocols.

My doctors are all amazed that I'm able to self-test and self-manage - it's easier to pass the responsibility for anticoagulation managementg to a clinic or a person in the office than to actually manage the patient's INR.

 

[ScribeWithALancet]

LAB and Coagucheck results will not necessarily match, if you call ROCHE ( they are very good ) they will say that best thing to do is stick to one method of testing because most likely will differ between lab and cxs, Me, i have been doing this for 5 years now, i use regularly coaguchek and once a month or 45 days, i go to lab, simply because blood tests are free for me; and there is always a diff of 0.1 to 0.3 INR; To give myself peace of mind, i aim to keep my INR around 2.5, since my valve is On-X and the range is 1.5-2 according to FDA, i am safe at any value above 2; so if, XS says 2.2 and LAB says 2, no matter, all is fine; I am not recommending this, just sharing what works "for me", also i take 1 asa 81 day; and Vitamin C-500, one thing balances the other; and per dosage, some times i take 3/3/2.5 others 3/2.5/3/2.5, depends on how close to 2.0 INR the test is; and i test every 10 days, Just sharing.

I tracked my last 7 paired laboratory blood draw tests and CoagSense blood tests. Then, using Apple's Numbers and Microsoft's Excel spread sheet, I did a regression analysis. Since I did not change labs between blood draws and used the same batch of test strips, I was able to get a correlation with an Rsquared of over 0.91. I was also able to get a regression equation that predicted the Lab INR based on the CoagSense INR within 0.1 every time.
In the meantime, the actual measured numbers varied from 0.1 with an INR of 3 (on the meter) to about 0.4 difference at an INR of 3.5 to 4 on the meter, and about 0.2 to 0.3 at about 2.3 on the meter.
Equally important, the plot of the Lab results marches up and down in lockstep with the CoagSense results. According to the Lab DIrector MD whose research guided me, the regression analysis has to follow the rules for conducting research. E.G. The laboratory cannot change machines or reagent and your INR test meter manufacturer cannot change reagents they use on your test strips.
This regression analysis has proven to me that my meter exactly matches my health plan's laboratory device. (You can get +-0.1 variation from the same machine on two consecutive draws - I saw a study where they demonstrated that). This makes sense given that, in theory, they are both matched with the same International Standard. If your lab will tell you what machine they use and whether they ever change reagents, then you could do the same correlation/regression analysis. The MD, whose original research I read, used both the CoagUChek and CoagSense. He was able to get good correlations with both. With both, they started to drift apart at values at below 2 and above 5. Fortunately, with weekly use, you can usually avoid those areas via midcourse corrections.
Walk in His Peace,
Scribe With A Lancet

 

[Protimenow]

Scribe---you wrote about your regression analysis on another thread. You mentioned a small difference between lab and meter. I understand this. When I was testing numerous meters (well, only five or six) against each other and against the labs, my Coag-Sense and CoaguChek XS meters usually correlated pretty well with the UCLA hospital's lab results - in fact, the average of the two meters often predicted the lab results.

I also understand the advice that I was given by a lab that I should only use one measurement, and stick with it.

However, when my meter says 3.0, and the lab says 5.4 - that's a big difference. When I was in the hospital, my INR the day before was 3.0, and the hospital's result was 4.7. I find it really hard to explain THAT MUCH difference. When I finally got home, I checked my INR using strips from two different batches - and, aside from a tenth of a second, both matched.

If I relied on a blood draw for INR, it's not unlikely that I would reduce my dose of Warfarin - potentially plunging my INR below 2, and actually creating a potentially disastrous situation.

I just lucked into some CoaguChek XS strips that expire at the end of May, so I can compare the results from Coag-Sense and CoaguChek XS. I expect that they'll be within 20% of each other. I'll post the results on one of these threads.

 

[ScribeWithALancet]

Scribe---you wrote about your regression analysis on another thread. You mentioned a small difference between lab and meter. I understand this. When I was testing numerous meters (well, only five or six) against each other and against the labs, my Coag-Sense and CoaguChek XS meters usually correlated pretty well with the UCLA hospital's lab results - in fact, the average of the two meters often predicted the lab results.

I also understand the advice that I was given by a lab that I should only use one measurement, and stick with it.

However, when my meter says 3.0, and the lab says 5.4 - that's a big difference. When I was in the hospital, my INR the day before was 3.0, and the hospital's result was 4.7. I find it really hard to explain THAT MUCH difference. When I finally got home, I checked my INR using strips from two different batches - and, aside from a tenth of a second, both matched.

If I relied on a blood draw for INR, it's not unlikely that I would reduce my dose of Warfarin - potentially plunging my INR below 2, and actually creating a potentially disastrous situation.

I just lucked into some CoaguChek XS strips that expire at the end of May, so I can compare the results from Coag-Sense and CoaguChek XS. I expect that they'll be within 20% of each other. I'll post the results on one of these threads.

Could it be that the hospital has two labs - one for inpatients and one for outpatients? The difference you got is huge. Even uncorrected, my differences have never been more then 0.5. Never 1.7 or 2.4.
It sounds like they have not calibrated the system they used against the World Health Organization ISI standard. Both CoagUChek and Coag-Sense are calibrated against that standard. It could not hurt to ask the hospital. They will probably not answer. I was able to find the machine and reagent my health plan used but never the last time they calibrated it.
At one time, I downloaded the Coag-Sense documents that they submitted to the FDA and they did a thorough job of documenting lots of tests for their calibration. I would bet on your meters and not on that disparate of a result.
Walk in His Peace,
Scribe With a Lancet
ps. Thanks for your advice on meters. My Coag-Sense 2 is working well although my skills with the transfer tube are still developing. I always get enough blood with the heating pad, a thermophore muff, but not always into the tube : - (

 

[tom in MO]

Some hospitals have labs, some hospitals farm out their lab work to commercial off-site labs and some hospitals do both. Also some hospitals have changed from in-house, to out-house, and then back to in-house. It depends upon the hospital and how large their network is and the services available in the local area.

 

[Protimenow]

I'm not sure if the hospital sent my blood out for PTT testing, but I doubt it. Some of these tests were STAT, so there shouldn't have been enough time to send the blood out and get a value - unless the contracted lab was actually located inside the hospital.

I've had similar issues with another lab, and was about to go to the FDA about it - after many calls, they never called me back, although they told me that they would.

The lab claimed that they check their reagents, according to a standard, and that their testing showed that it passes required stndards for accuracy. The hospital probably also claims that they do the same. However, I wouldn't want to trust my life to either lab -- they may reduce my dose and cause my INR to drop over a few days -- and keep it, perhaps, below 2.0. I'd rather trust my meter.

FWIW - I just got a few strips for the CoaguChek XS, so I'll compare readings between meters. I fully expect them to be within .2 - .4 of each other.

Scribe -- I had trouble with the transfer tubes at the beginning. I found that, for me, reading the directions and following them helped reduce the number of faulty fills of the tubes. I'm certainly not suggesting that you haven't read the instructions.

I found that what helps sometimes, although they suggest holding the tube horizontal, then touching the drop of blood, I slightly lower the tube, so the blood doesn't have to flow against gravity. I hope this helps.

If you don't get enough blood into the tube on your first try, use a different finger and try again. The Coag-Sense strips are very forgiving -- they'll wait a long time before you put the blood onto them. If they time out, remove the strip, tell the meter that you want to run a test, and reinsert the strip. As long as you haven't already put blood onto the strip, you should be able to run the test -- even if you spend many minutes before you draw a good droplet of blood into the tube.