PT,PTT,INR and coumadin, explain it all please?

[scootermcnutt, RN]

I just need a BASIC explanation of the connection of PT, PTT, INR and coumadin. What elevated and low lab values mean, etc? For some reason this is one of those things that perplexes me.

[whipping girl in 07, RN]

PT: prothrombin time...tells you if pt's coumadin is at a therapeutic level. If it's low or normal and the patient is on coumadin, then the dose is not therapeutic and needs to be increased.

INR: international normalized ratio...still has to do with coumadin therapeutic level. When lab runs a PT you get INR results also. 2-3 is therapeutic. If it's a lot higher, the patient probably needs some vitamin K to counteract it so he won't start bleeding all over the place.

PTT (aPTT): (activated) partial thromboplastin time...tells you if patient on heparin is at a therapeutic level. If it's low or normal and the patient is on heparin, then the dose is not therapeutic and needs to be increased. We use a sliding scale for heparin, increasing or decreasing the dosage based on APTT results.

Coumadin: anticoagulant that take several days to start working, so heparin is given at the same time till the coumadin level is therapeutic.

Protamine: antidote for heparin (use is patient's APPT is sky high); works quickly.

Vitamin K: antidote for coumadin; works slowly.

I hope this helps you get it straight.

[P_RN, ADN, RN]

PT (prothrombin time) measures coumadin effect (warfarin). antidote vit k

*warfarin works slowly/ vit k works slowly.

The thromboplastin (testing material) various labs used was different so the results were different lab to lab. So labs started reporting inr with the pro-time.

The INR (international normalized ratio) is calculated with a math. formula so all results from all labs can be compared.

FYI: hemophiliacs have normal pro-times.

PTT (partial thromboplastin time) measures heparin effect. Antidote is protamine.

*heparin works quickly/protamine works quickly

[cbs3143]

For faster reversal of an elevated PT/INR, my facility gives fresh frozen plasma as well as some vitamin K. The intracraneal hemorrhage patients or GI bleeders with elevated PT/INRs, almost always receive FFP to bring their PT/INRs back down.

Chuck

[Zhakrin]

It was explain to me as such the INR is a ration and 1 is consider the normal clotting value of a person with not medical history.

Because its's a ration, a INR of 2 is explained as taking twice as long to clot as a reading of one, so they clot more slowly. The higher the INR the slower the clotting factor and higher the risk of hemorrhage is. A INR is therapeutic when it in the prescribed range, but can be dangerous if its to high.

This is how I keep it straight, anyway good luck.