Understanding PT & INR

[rsyed47]

Hello,

I have a pt. with PMH of HTN, a.fib, GERD, CVA, and DVT.

She is currently taking these meds:

baby Aspirin

Chlorthalidone

Digoxin

Metoprolol

Wafarin

Hydralazine

Her PT level is 27.9.

Normal range at institution is 9.9-13.2 sec.

INR is 2.3.

Normal range is 2.0-3.0 (for pt.s with a.fib).

I'm having a difficult time understanding why her PT level is so much higher than her INR. On admission her PT lvl was 39.7 and INR 3.2. This was 3 days ago.

[akulahawkRN, ADN, RN, EMT-P]

https://labtestsonline.org/understanding/analytes/pt/tab/test/

That page is a start for PT/INR. You also might want to try to search for "PT and INR" on your favorite internet search engine to find more information. Just be sure that the info comes from a reputable source.

[calivianya, BSN, RN]

Here's the thing - you're comparing a normal PT range to the INR range for someone who needs to be anticoagulated. An INR of 2-3 is not normal - that's just normal with anticoagulation. A truly normal INR with no interference is something like 8.0-1.2.

So, let's take a better look at those admit numbers.... 3.2 is almost three times 1.2 and 39.7 is almost three times 13.2. It seems like they correlate pretty closely to me.

[rsyed47]

Ohhh okay, I understand it now! 1st year nursing student, could you tell? Thank you so much.

[rsyed47]

Thank you for the reference--it's very informative!