Other than the normal values, what is the difference between the APTT and the PTT? Since the lab values are difference, I would "assume" that there has to be some different between the two, other than the name. All I find is that PTT is also called APTT, however, this really confuses me since their normal values are very different.
What would you use one for, but not the other?
Oct 2, '04
The APTT and the PTT are
the same. The Activated Partial Thromboplastin Time and the Partial Thromboplastin Time are the same--the second one's just abbreviated.
You'll usually use this test for a patient who is on Heparin. The heparin protocol will call for parameters on the rate of heparin to run based on the APTT. The order will read something like "If APTT 25-36, increase to 10 units/hour and repeat APTT in 6 hours."
Now, the PT--or Prothrombin Time--is a different type of measure of coagulation that's usually used to determine how much Coumadin a person has in their system. And more often, we use the INR as the parameter, which is the second half of that test. The lab order will read "PT/INR daily" or something like that.
You'll usually see an order for a patient like "Coumadin 3 mg po qd. Hold if INR >2.8."
I could go on and on....
...let me know if you have more questions about anticoagulation. I'll be happy to share info.
Last edit by UM Review RN on Oct 2, '04