PT/INR help!!!!

core0 · Oct 11, 2010

ok, I need some help before I kill someone. Does anyone know of a site or have easy info for treating abnormal PT/INR levels.
I am so confused. Most of the pts I see need to keep their level between 2-3. How do you decide how to adjust the dosage? Is there a set scale or something.?
Then, the other day a I had a perfectly normal person come in with a horrible bruise on her leg about 9inches in diameter. she said she got it after having a really be charly horse.
she had no medical issues or problems, not on any meds. I did a PT/INR on her and it was .8. I freaked out thinkikng it was really low but my collaborative said below one is normal, so I am totall confused.
Can someone explain this in an easy way to understand it. Thanks

First of all here is the best guideline I have found for INR adjustment (courtesy of UCLA):

http://medres.med.ucla.edu/Practices/Guidelines_anticoagulation.pdf

You are really asking three questions:

1. How do you dose Coumadin. Basically start at a reasonable dose say 7.5 or so for a fifty year old with afib and no other health problems. The second day cut it to 5. Check INR daily and adjust up and down as needed. Some people will give a first dose of 10 then go to 5. Most people will need around 3-7mg per day. Assess for risk ie if you overshoot. If they have higher risk then go low and slow. The UCLA guidelines do a better job explaining than I do.

2. How do you reverse anti-coagulation. Basically first decide if you need to reverse it. Most hospitals have guidelines that are usually taken from the ACCP recommendations last updated in 2009:

http://health.usi.edu/summaryoftheseventhaccpconference.pdf

Basically you decide if they are bleeding or not and how much risk they have. The thing that you have to remember is that large doses of vitamin K will make it hard/impossible to raise the INR for 10-14 days. The cardiologists are hardly going to be happy if the patient is found to have an INR of 4.5 without bleeding and you give them 10 mg of Vitamin K IV. On the other hand if the patient is gushing blood from every orifice with an INR of 12 you have pretty much free reign to do whatever you want (including giving prothrombin complex concentrate or recombinant factor VIIa). Things in the middle require more judgment. I am especially wary of making big changes on people with valves that don't have significant bleeding.

A couple of other things that I have learned the hard way. FFP has an intrinsic INR of 1.4-1.6. If you are trying to reach that magic INR of 1.5 using INR alone you will have a very hard time. Just tell radiology to put on their big boy pants and come do procedure (hang a unit during the procedure if that will make them happy). I have seen any number of patients put into CHF while someone was chasing that last .1 or .2 to make it 1.5. If you want the INR corrected and to stay corrected fairly rapidly you have to give Vitamin K. If you don't want to anger the cardiologists (see above) then try a small dose of oral or IV (0.5 mg IV or 1 mg oral). FFP by itself will give you an INR rebound in around 12 hours. Its very hard to correct the INR of someone with end stage liver disease. Most often you can't.

3. How do you work up easy bruising. Remember from your clotting cascade there are a lot of mechanisms for defective clotting. Is the patient on ASA or Plavix. Is the patient on Lovenox. Is the patient on some other medicine that inhibits PLT function. Bruising is not always (usually isn't) about the INR. Here is a nice article from AAFP that discusses working up the patient with bruising:

Bleeding and Bruising: A Diagnostic Work-up - April 15, 2008 - American Family Physician

David Carpenter, PA-C

Trauma Columnist · Oct 12, 2010

SKyscape has an app called Anticoagulation Guide also.