How to Monitor the Anticoagulation with Lovenox?
62 yo CM with complicated PMH, including GI bleeding from esophageal varices, colon cancer and CRI, is hospitalized with DVT. He is obese and had a hemicolectomy 3 weeks ago. Lovenox (enoxaparin) is started, Coumadin use is contraindicated due to history of GI bleeding. He will need anticoagulation with Lovenox for 6 months. Is there any way to know if Lovenox dose is therapeutic? What do we check? – factor Xa – PTT – PT – anti-Xa level You have to check anti-Xa level. This is NOT factor Xa level, which most likely will be normal with Lovenox therapy. PTT is useless in monitoring therapy with LMWH. PTT should be used to monitor treatment with UFH, i.e. regular IV heparin. What is anti-Xa level? Is it some special factor anti-Xa? No, there is no factor anti-Xa. There is a factor Xa, just like the other 12 factors in the anticoagulation cascade (there is no factor VI). Anti-Xa level is determined by a simple mixing study. Patient plasma is added to a known amount of factor Xa with antith
