INR mismanagement

[Troy]

I live in a small town in SE Oklahoma. (We have one red light in the county!) We have three doctors in town, I use the best of the three, in my opinon. I have my blood drawn at the local doctors office weekly. I go by in the morning and get the results the next evening. I have tested 12 weeks and my INR has been in range, (2.5-3.0) three times. The Dr seems more concerned about my PT than the INR. Two weeks ago my INR was 2.6 and the PT was 21.7. (This was after taking 3 mg Coumadin for two weeks and both the INR and PT had dropped from 3.36 and 25.1.) The doctor wanted me to adjust my coumadin down to 2.5. (I stayed on 3 mg.) This last week it had went down to 2.34 INR and 20.4 PT. Then he said to go down to 2mg daily! Luckily I have my thoracic surgeon's cell phone. I called him and he said to take 4mg. He was pretty excited when I told him of my experience. He called the dr here to see if he can help educate him.

I am 3 hours from OKC, Dallas and Tulsa. Is there a way to educate myself about management of my Coumadin/INR. Is there a website that I can plug in my INR numbers and get the Coumadin dosages? Like an online anticoagulation clinic? Any ideas?

I do have an appointment with the cardiologist Aug 22nd.

I am in process of getting a finger stick machine, my insurance has initially denied it. The doctors office still does the needle sticks, which hurt. I tried to tell them about the new painless finger prick machine. They weren't interested.

I have read very little about the Protime, much more about the INR. Is the PT an important factor? Should I sacrifice my INR level to get the PT in range?

Any help/education would be greatly appreciated....................

 

[Karlynn]

Troy,
The protime # is the old way of managing warfarin (Coumadin). The fact that your doctor is more concerned with the protime # than the INR and is adjusting your dose according to the protime, shows that he has absolutely no business managing your Coumadin because he is basing his decisions on totally outdated information..

The reason the INR was developed was because there was way too much variation in the protime numbers. My INR can be in range and my PT will be all over the place. I have a new INRatio machine and I have it set to show only my INR because the PT is just useless information for me. Your doctor would flip out if he saw some of my PT #'s.

Also, the fact that he is waiting until the next day to adjust your dosage is also a sign that he doesn't know what he's doing. You should get your # and any dosage change the day you test.

If your INR is fairly stable and stays in range, there really isn't a reason for you to test weekly.

Have you been to Al Lodwick's site? www.warfarinfo.com You'll want to bookmark this site.

This site http://www.aafp.org/afp/990201ap/635.html has dosing charts about 1/3 of the way down. They are for ranges of 2 - 3 and 2.5 - 3.5. Notice that they don't even refer to PT.

Here's an interesting article http://www.medicinenet.com/script/main/art.asp?articlekey=57700

There is no site that I know of that you can plug in your INR, dose and get suggestions. But it's not that hard to figure it out yourself with a little education.

You are a prime candidate for a home tester. The fact that your doctor still uses PT as his dosing #'s should be a huge sign to your insurance company that they need to get you a home testing unit.

My minds a little scattered today , so I may be here, there and everywhere. Hopefully others will come along and be more clear.

Maybe you can get your thoracic surgeon to contact your insurance company and explain your extremely important situation and plead on your behalf for a home test unit. You already know more than you think you do (and definitely more than your doctor!)

Best wishes!

 

[Nancy]

The first problem I see is this, "I go by in the morning and get the results the next evening". This is a useless result. You HAVE to get your results and instructions the SAME day as the test, no matter what, NO EXCUSES from your doctor.

That in itself is bad management.

Your inability to get it under control could come merely from that alone!!!

Make your doctor's office call you with the results and instructions the same day and then see if it makes a difference.

And don't take NO for an answer. Be very strong on this issue.

 

[Karlynn]

Just wanted to reiterate, because it's SO important. Do not let your doctor adjust your dose according to your PT. Only use the INR. If your range for your INR is 2.5 - 3.5 and your INR is within that range (or if your range is 2 - 3) and he's trying to adjust your dose because your PT is "out of range", ignore him, please. Even if your range is up to 3.5 and your INR is 4, you really shouldn't be adjusting the dose for that. PT is hugely inexact and INR, while much more correct is still inexact by as much as .7 (I think )

 

[RandyL]

Altering Wayfarin Dosage to maintain INR of 2 to 3

Altering Wayfarin Dosage to maintain INR of 2.5 to 3.5

 

[ALCapshaw2]

The INR measurement system was developed to ELIMINATE the variation in PT due to reagent sensitivity.

Anyone using PT as their standard is 20 years behind the times. You may want to talk with the other Doctor's in town to see if either of them are 'up to date' with INR testing.

You can buy a DOSING GUIDE from AL Lodwick's site www.warfarinfo.com for $5. It is WELL WORTH the investment.

'AL Capshaw'

 

[Blanche]

Troy, this is not just mismanagement, it is malpractice. THE INR was developed by the World Health Organization to deal with problems in using just prothrombin time (p/t) in making decisions about anticoagulation medication. What the "medical" people you are dealing with are doing is putting patients in jeopardy. This is not some new fangled thing. THe INR was developed more than 25 years ago, as Al Capshaw said. I am including here some more information on the International Normalized Ratio. You might want to share these with your "medical" people.

http://www.enw.org/Research-INR.htm
http://www.hepatitis-central.com/hcv/labs/inr.html
http://path.upmc.edu/consult/rla/june1995.html

Kind regards,
Blanche

 

[Karlynn]

Troy, the charts that Randy provided are the ones that are 1/3 of the way down in that one web article I gave you. Thanks Randy!

I would like to add that while the charts will say "withhold no to one dose" or "withhold no to two doses" many of us are very cautious about holding doses. We'd rather do a % adjustment. Some of us have found that holding a dose (particularly if you're 5 or less) can send your INR swinging too low.

I can only think of one time in almost 15 years that I've held a dose.

You should also know that the larger amount of warfarin you take, the faster your INR will drop when holding a dose. I take 10/day on average. I drop like a rock with a held dose. My INR went from 4.7 to 2.4 in a week with just a 10% decrease.

I just reset my INRatio to show both INR and PT so I could tell you what my PT's were. Today with my INR being 2.4 (slighly below range), my PT is 23.9. Last week, when the INR was 4.7, the PT was 47.3 My guess is if your doctor saw a PT of 47.3 he'd freak out and have you hold for a week or admit you to the hospital.

Prior to the use of INR, I recall my PT range being in the low 20's. I never have a PT in the low 20's if my INR is in range. Times have changed and I am much safer now than when PT's were used.

You may also want to take a look at this new thread http://valvereplacement.com/forums/showthread.php?t=17116 It is one a few of us seasoned warfarin users thought might be helpful. You'll notice that PT isn't even mentioned because it isn't used any more.

 

[RandyL]

I think if you will look back thru your records you will find that your INR is always(mine is anyways) 10 percent of your PT value. With this being tru then I would venture to say that you could use the PT number as well.

 

[Karlynn]

I think if you will look back thru your records you will find that your INR is always(mine is anyways) 10 percent of your PT value. With this being tru then I would venture to say that you could use the PT number as well.

Roughly, yes! My old ProTime home tester had more variance. Curious. I wonder if it's an INRatio thing? One could conclude that if your INR is just 10% of your PT, then what was the problem with the PT. (And we know there were problems with PT)

Here's history from my old ProTime machine (INR > PT) (Troy - "the ProTime" is also a brand name of a home testing machine)
3.9>50.1
3.0>39.2
3.6>47.0
2.7>35.2

Not to hijack the thread, but did the INRatio just decide to make the PT 10x's the INR just because some people like to see the PT, but it really is meaningless?????

Randy, looks like you've stumbled upon something.

 

[PJmomrunner]

A free guide:

http://www.aafp.org/afp/20050515/pocform.html

 

[Blanche]

INR is just a mathematical calculation that controls for the variable ISI (International sensitivity Index). When Al was doing fingerstick at the labs, the ISIs of his reagents varied every time a new batch of reagents were used. Actually, a number of people died at a hospital in Pennsylvania some years ago when the lab folks failed to compensate for a change of ISI in the new reagents. (Reagents=the stuff they use to make the test) The ISI of the ProTime Microcoagulation System is always 1.0. THe ISI for the Coaguchek is greater than 1.0, but I don't remember the exact number. THerefore, for the same test the p/t on these machines would not be the same but the INRs would be the same. (p/t=prothrombin time)..the time it takes for a sample to coagulate...

Perhaps the following will help:



To help standardize this difference two formats were developed, the first was the International Sensitivity Index (ISI) and the second was the International Normalized Ratio (INR). The INR was developed to incorporate the ISI values and attempt to make PT results uniformly useable. The manufacturers assign an ISI to each batch of reagent after comparing each batch to a "working reference" reagent preparation. This "working reference" has been calibrated against internationally accepted standard reference preparations which have an ISI value of 1.0 (Ortel, 1995). By definition, the more sensitive thromboplastin have an ISI of less than 1.0 and the less sensitive are greater than 1.0. The ISI value is critical for calculation of the INR, because the ISI value is the exponent in the formula. Consequently, small errors in the ISI assignment may affect the calculated INR substantially (Florell & Rodgers, 1996).

To resolve the problem of highly variable PTs, the use of the INR has been recommended for monitoring patient's oral anticoagulant therapy. This recommendation is supported by the American College of Chest Physicians, the National Heart, Lung and Blood Institute and the British Society for Hematology (Nichols & Bowie, 1993).

It is important to emphasize that the INR is not a new laboratory test. It is simply a mathematical calculation that corrects for the variability in PT results attributable to the variable sensitivities (ISI) of the thromboplastin agents used by laboratories.

INR = - patient PT______ ISI
OR
INR = {PTR}ISI
Mean normal PT


PTR- is the prothrombin time ratio, which is the patient's observed PT (in seconds) divided by each laboratory's calculated mean normal PT (in seconds) (Ortel, 1995, Florell & Rodgers, 1996).

 

[ALCapshaw2]

SNIP - I go by in the morning and get the results the next evening. I have tested 12 weeks and my INR has been in range, (2.5-3.0) three times. The Dr seems more concerned about my PT than the INR. Two weeks ago my INR was 2.6 and the PT was 21.7. (This was after taking 3 mg Coumadin for two weeks and both the INR and PT had dropped from 3.36 and 25.1.) The doctor wanted me to adjust my coumadin down to 2.5. (I stayed on 3 mg.) This last week it had went down to 2.34 INR and 20.4 PT. Then he said to go down to 2mg daily!

I do have an appointment with the cardiologist Aug 22nd.

I am in process of getting a finger stick machine, my insurance has initially denied it. The doctors office still does the needle sticks, which hurt. I tried to tell them about the new painless finger prick machine. They weren't interested.

I have read very little about the Protime, much more about the INR. Is the PT an important factor? Should I sacrifice my INR level to get the PT in range?

Any help/education would be greatly appreciated....................

WHO set your INR target range at 2.5 to 3.0?

That is tighter than most Cardiologists recommend,
and VERY difficult to maintain, especially given that there is some variation in readings, even if taken at the same time.

MOST Aortic Valve Patients with NO other risk factors are advised to keep their INR between 2.0 and 3.0. Most Mitral Valve patients OR Aortic Valve Patients with other risk factors (read Stroke) are advised to use 2.5 to 3.5 for their target range.

Asking a patient to REDUCE his Coumadin dose WHEN IN RANGE is FOOLISH and RISKY. MOST Anticoagulation Managers would NEVER advise a dose change for an INR reading that was only out of target range by 0.1. Instead, they would advise a retest in a week, or more likely, in two weeks. Continuously changing dose is GUARANTEED to have your INR varying all over the place since it takes 3 or 4 days for each dose to be fully metabolized.

The SAFE RANGE for Coumadin is generally considered to be between and INR of 2.0 and 5.0 so there is LOTS of 'wiggle room' to accomodate various additional risk factors. Even above 5.0, many patients do NOT bleed spontaneously.

I hope your surgeon was able to 'educate' your local doctor and bring him up to date in this Coumadin Management.

'AL Capshaw'

 

[perkicar]

perkicar hits a new INR high!

perkicar hits a new INR high!

Very interesting thread since I just got back from getting my INR tested and it was (drum roll please!!) 5.7. I was told to hold today's dose and wait for them to call me if I had any dosing changes. I knew I was high because I got a bug bite this weekend that oozed for several hours! But I only guessed 4, not greater than 5! Sure surprised the nurse checking me!
I'll let you know what they tell me to do!

Carolyn

 

[Troy]

The family dr told me the range was 2.5 to 3.0, I'll double check with the surgeon. The information posted by you guys has been very helpful. I appreciate it. I knew I had read about INR but not much about PT. Guess that is why. What is bad is there are lots of older folks being checked for anticoagulation here and they don't know to question the doctors. They do not know there is a simple, quick, relatively painless, finger stick machine. That is the sad part.

 

[Ross]

Hehehe hey Troy, looks like your getting the same answers in stereo Eh?

 

[PJmomrunner]

My parents are both on ACT and they both insist on those painful blood draws because they say their doctor says the finger prick tests are not accurate and their experience bears that out. I have tried to tell them that the finger prick numbers are different, and probably more accurate, because they get their results immediately. They have absolutely no interest in second-guessing the doctor. They don't even ask for results and they are only told their results if they are out of range or if they are traveling and have to call-in their numbers. I just keep my fingers crossed.

 

[catwoman]

Troy:

There are many good articles about warfarin at Al Lodwick's website, www.warfarinfo.com. I have several of his dosing charts (misplaced one once, so I bought a 2nd one, then found the first one) and his spiral-bound book on warfarin.

I've learned to arm myself with printouts of articles about warfarin when going to a doctor (i.e., bridging therapy for various procedures, etc.). Luckily, my family doctor is knowledgeable about anticoagulation management, and trusts me to self-test and adjust my own dosage.

You're not far from the OK-TX line. I've been through Antlers a couple of times en route to Tulsa from my sister's home at Lake Bob Sandlin near Mount Pleasant-Pittsburg TX. There is an anticoagulation clinic at the regional hospital in Mount Pleasant (I think it's Titus Regional Hospital, probably a county-supported facility) and another in Greenville, according to www.acforum.org. Looks like those are the closest ones to Antlers OK.

 

[Karlynn]

Troy, the standard for an AVR is 2 - 3. Some doctors choose to go higher to the 2.5 - 3.5. A .5 range is just too small to allow a patient to stay "in range" and can cause too many fluctuations and changes in dosing. But it sounds like you are pretty stable for the most part.

You are so right about the older patients. It does make you worry for them. Plus they are the generation where doctors are next in line to God and you just don't question them.

 

[Guest]

When I started doing anticoagulation in 1997, one doctor told me that he, managed his own pro-times. A cardiologist told me that the doctor who said that was so far behind the times that he should not be allowed to practice. It has been several years since I have heard about protimes from a doctor who is still in practice.

Knowing the protime is about as useful as a sportscaster saying, "Yankees 4".

The 0.5 unit range is another tipoff that this doctor is unfamiliar with warfarin. It is hard enough to keep somone in a 1.0 unit range. If the doctor took the time to think this through he/she would come to the conclusion that it makes no difference in your outcome (unless you die from worrying about the INR being out of range).

A new patient asked me today why her former warfarin manager told her that she couldn't eat green vegetables. If you think this one through you have to conclude that the former manager was saying, "I know what warfarin dose you need and you have to do everything that you can to make this dose work." Then I told her that my way of thinking is that you should livethe life that you want and I'll make the warfarin dose fit you. I got a long stare as she considered that but she had no rebuttal.