Help explain INR and PTT

Nursing Students Student Assist

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I am a nursing student in my 3rd semester and I am still having trouble understanding INR and PTT. Can some one explain to me ?

My pt. is on heparin for DVT..how can I tell if it is therapeutic or not ?

Thank you in advance.

Specializes in Pediatric/Adolescent, Med-Surg.

Why do you think it would be high? Look up the anticoagulant your pt is on in your drug book and understand how the drug works. Pay attention to if the book mentions a target INR for different treatment plans such as a DVT

I am a nursing student in my 3rd semester and I am still having trouble understanding INR and PTT. Can some one explain to me ? My pt. is on heparin for DVT..how can I tell if it is therapeutic or not ? Thank you in advance.

Correction, you are currently in your third semester of nursing school and you are still having trouble understanding how to utilize your resources and think critically.

Never expect someone to think for you until you try thinking for yourself. But here's a "gimme" anyways:

https://allnurses.com/nursing-student-assistance/questions-pt-ptt-161106.html

https://allnurses.com/nursing-patient-medications/pt-inr-ptt-595535.html

https://allnurses.com/nursing-patient-medications/heparin-high-inr-834675.html

https://allnurses.com/nclex-discussion-forum/please-help-me-107985.html

https://allnurses.com/nclex-discussion-forum/ptt-question-410987.html

Specializes in Family Nurse Practitioner.

emedicine.medscape.com/article/2086058-overview‎

emedicine.medscape.com/article/1927155-overview‎

emedicine.medscape.com/article/2085837-overview‎

There are reference ranges/normal values for PT/INR and (A)PTT. The practitioner wants the level high, but not high enough that it can cause spontaneous bleeding i.e. critical value. If the patient is on a heparin drip for DVT, the dose may be adjusted every day as needed depending on the APTT or PTT. It's adjusted at my facility on a sliding scale. The activated (A) PTT is more accurate than the PTT. If INR is not high enough, Coumadin may be added the mix. Remember CoumadIN® and heparin = PTT.

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

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.

PTT: At a Glance | Partial Thromboplastin Time

https://allnurses.com/nursing-student-assistance/some-questions-about-138487.html

Suggest the wonderful resource, Laboratory and Diagnostic Tests with Nursing Implications, by Joyce Lefever Kee, the most recent edition is the 9th. Not only gives you ranges, but gives you rationales and, well, nursing implications. Get it, and next thing you know, you'll be answering this question on AN.

Laboratory and Diagnostic Tests with Nursing Implications (9th Edition): Joyce LeFever Kee: 9780133139051: Amazon.com: Books

Specializes in Emergency.

Our patho teacher taught us to count coumadin and heparin using our fingers. With coumadin, you have two fingers left, so you look at PT/INR. Heparin, you have three fingers left, so you use PTT. I always thought that was super helpful for me, lol.

I used to draw it on the whiteboard:

I'd write "cOumadin" across and "prO time" going down, with the O shared by both.

Then Heparin and PTT, with the H and the TT looking pretty much the same and intersecting.

Whatever works for you is fine!

Specializes in ICU.

When I was on coumadin, my hematologist set a level for me that was therapeutic. I had to have my blood tested at least once a week where they pricked my finger and put my blood in a machine show they could tell my PT/INR. That told them how fast my blood was clotting. If it was too high, I would bruise like a peach. My level was supposed to be 2.5-3.0. One time it got up to 11.1 and I had at least 150 bruises on my body and was in horrible pain. Went to the er and I seriously looked like someone had beat me. They gave me vitamin K to reverse the effects and I started over again. If my level was below 2.5 they would up my coumadin dose. Some weeks I took more than others and many things can affect PT/INR levels. I was not allowed cranberry, lots of green leafy vegetables, stuff like that. No taking aspirin or anything that could thin the blood more. It is a very delicate balance and that is why you must be tested often. Glad I am off of it now, went 3 years without any clots and my doctor took me off. Yay me!!

Many people including, alas, physicians and nurses who know better, refer to anticoagulation medications (both antiplatelet and those acting on other parts of the clotting cascade) as "blood thinners." Unfortunately, and inaccurately, this puts people in mind of paint thinned by solvents or watered-down milk, or maybe thin, inadequate clothing.

The problem then becomes that they are not aware of the actual physiological reason their medications are prescribed to reduce risk for embolic events, either stroke or deep vein thrombosis and pulmonary embolus. I have had patients tell me they are "always cold since taking that blood thinner." The risk of discontinuing the medication because the effects are inaccurately communicated is great, and very real.

Anticoagulants do not "thin" the blood. They decrease blood clotting to decrease the chances of a clot in the heart from developing (causing stroke after it travels), or clot in a vein developing (and then traveling to the lungs) or preventing it from growing larger while the body's natural processes break it down for disposal. Side effects include easier bruising and bleeding, as heathermaizey so graphically describes.

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