Anti-coagulants

iteachob, MSN, RN · Feb 22, 2009

I am a graduating student nurse (this May)...We have a test tomorrow...we need to know the pt, ptt and INR normals and theraputic levels. I am getting conflicting information regarding which tests you watch with Lovenox...do you monitor pTT and INR...Could someone please clarify this for me, before I go crazy!!!
Thanks

Lovenox is a low-molecular weight heparin; it has a longer half-life and and bleeding is less likely than with heparin. PTT and aPTT are used to monitor heparin therapy. However, one of the reasons Lovenox is able to be administered at home (heparin requires hospitalization) is because aPTT monitoring is not necessary (LMWH overdose is rare).

PT and INR are for Coumadin.

RedCell · Feb 22, 2009

If you want to measure the effects of lovenox, the most common methods include obtaining an activated clotting time (ACT), a thromboelastogram (TEG), or an anti-Xa level. ACT is the most practical and cheapest.

pagandeva2000, LPN · Feb 22, 2009

Lovenox is a low-molecular weight heparin; it has a longer half-life and and bleeding is less likely than with heparin. PTT and aPTT are used to monitor heparin therapy. However, one of the reasons Lovenox is able to be administered at home (heparin requires hospitalization) is because aPTT monitoring is not necessary (LMWH overdose is rare).
PT and INR are for Coumadin.

Thanks for sharing. Are any of these levels (APTT, PT, INR) measured while taking Lovenox?

HARLEYBEAR · Feb 22, 2009

Thanks for your responses....but what tests are measured while on Lovenox...just ptt?

highlandlass1592, BSN, RN · Feb 22, 2009

You don't usually monitor any test while on lovenox. You will sometimes find they run a PTT for a comparison to baseline but if you really want to monitor a lab (when I did homecare, none of our physicians ever did) you'd probably run the anti-Xa level. For all the years I've seen it used, I've never seen routine testing ordered.

pagandeva2000, LPN · Feb 22, 2009

Thanks for your responses....but what tests are measured while on Lovenox...just ptt?

I just looked in my drug book and it says to monitor PT and INR.

highlandlass1592, BSN, RN · Feb 22, 2009

Thanks for sharing. Are any of these levels (APTT, PT, INR) measured while taking Lovenox?

Not usually...I've posted a link about lovenox facts here: http://www.aahcp.org/dvt/faqs.htm Pretty much squares with what I've seen when I did homecare. We use lovenox now (at the job I'm at) for bridging patients off coumadin for surgery prep...and this is pretty much the info we use for that too. Hope it helps.

highlandlass1592, BSN, RN · Feb 22, 2009

I just looked in my drug book and it says to monitor PT and INR.

Unfortunately, the way lovenox acts affects the factor Xa..which the PT, INR will give you no indication of. Which is why you'd check the anti-Xa factor. I'm not really sure why your drug book says to monitor the PT, since the lovenox wouldn't affect those values. I'm guessing it's just part of keeping on an eye on coags in general when on any form of anti-coagulation. If the INR goes crazy, it may lead us to (in some pt's) work them for hematological disorders. Truth be told, any patient on anti-coag therapy should also have at least a weekly CBCP (cbc with platelets) ordered to monitor for thrombocytopenia.

pagandeva2000, LPN · Feb 22, 2009

Unfortunately, the way lovenox acts affects the factor Xa..which the PT, INR will give you no indication of. Which is why you'd check the anti-Xa factor. I'm not really sure why your drug book says to monitor the PT, since the lovenox wouldn't affect those values. I'm guessing it's just part of keeping on an eye on coags in general when on any form of anti-coagulation. If the INR goes crazy, it may lead us to (in some pt's) work them for hematological disorders. Truth be told, any patient on anti-coag therapy should also have at least a weekly CBCP (cbc with platelets) ordered to monitor for thrombocytopenia.

Again, I thank you for sharing your information. One of the things that annoys me with these drug books is that I noticed that their information does not always collaborate. I just searched another drug guide that states to monitor CBC and platelet counts, and these guides are only two years apart (different companies, though).

highlandlass1592, BSN, RN · Feb 22, 2009

Again, I thank you for sharing your information. One of the things that annoys me with these drug books is that I noticed that their information does not always collaborate. I just searched another drug guide that states to monitor CBC and platelet counts, and these guides are only two years apart (different companies, though).

You've got a great point about differing drug books focusing on differing things. I've found it's best to research the action of the drug and try to take it from there. I've used some references docs use and found it be very helpful. (And it's helpful to anticipate what types of orders they might give.) Drug manufacturing sites are a big help, the pdr is invaluable but honestly a lot of what I've learned has started out with nursing drug books and taken off from there. I ask a lot of questions of the docs and have no problem calling the pharmacist on duty to pick his or her brain as well. I'm blessed to work at a teaching facility so we deal with a lot of differing disciplines and they really can teach you a lot about the drugs they like to use.

You know, just had a thought. If you have a PDA, you may want to think about a program like epocrates or micromedex. They have a bit more information than our normal nursing drug books and can be a real help. Just a thought to share.

pagandeva2000, LPN · Feb 22, 2009

You've got a great point about differing drug books focusing on differing things. I've found it's best to research the action of the drug and try to take it from there. I've used some references docs use and found it be very helpful. (And it's helpful to anticipate what types of orders they might give.) Drug manufacturing sites are a big help, the pdr is invaluable but honestly a lot of what I've learned has started out with nursing drug books and taken off from there. I ask a lot of questions of the docs and have no problem calling the pharmacist on duty to pick his or her brain as well. I'm blessed to work at a teaching facility so we deal with a lot of differing disciplines and they really can teach you a lot about the drugs they like to use.
You know, just had a thought. If you have a PDA, you may want to think about a program like epocrates or micromedex. They have a bit more information than our normal nursing drug books and can be a real help. Just a thought to share.

I am appreciative of what you have shared thus far and plan to take advantage of it. Thank you.