Anticoagulant Therapy

More About Oral Anticoagulants

Question from a colleague: My 92-YO dad has atrial fibrillation and is on warfarin. He is well controlled and since he is independent and drives, getting monitored is not a big deal…while the pavement is dry. However, I am worried that he will venture out when he should not during the winter when he has […]

Anticoagulant Therapy

More on INR 10.0

Thanks to Vadim Kostousov for his comments appended to the September 28, 2013 post, Accuracy of an INR of 10.0. Here are the guidelines from the latest edition of the ACCP guidelines Chest 2012 Exec Summary: 9.1 Vitamin K for Patients Taking VKAs With High INRs Without Bleeding (a) For patients taking VKAs with INRs between 4.5 and 10 […]

Anticoagulant Therapy

Quick Question: Pradaxa Measurement

Glen Holloway asks if it was possible to add “in-house dilute thrombin time” to the current Quick Question list. George promised to update this in July, and will finally keep his promise. The current Quick Question was: The new oral anticoagulants are being used more and more. How do you plan to measure dabigatran (Pradaxa) levels? […]

Anticoagulant Therapy

Accuracy of an INR of 10.0

From Eleonor Arellano: Thank you for presenting a very informative seminar, “Whatever Happened to the PT and PTT?” about the new anticoagulants last Friday at Rancho Mirage. Our ER physician is requesting the laboratory to increase the reporting of international normalized ratio (INR) of ER patients up to 10.0 INR. What are your thoughts about that? […]

Anticoagulant Therapy

Check AT Before Starting Heparin?

George,would it be better to check the patient’s antithrombin III (AT III, antithrombin, AT) level before starting unfractionated heparin (UFH)? Regards, Frances Weekes. Hi, Frances, thanks for the question, and while I’d be happy to invite other opinions from our participants, I would not recommend screening for AT levels on everyone starting unfractionated heparin for the […]

Anticoagulant Therapy

Anticoagulants and Ketogenic Diet

From Maria Jose Lauria: I would like to know if you have any experience in patients with oral anticoagulants and ketogenic diet given to patient with seizures. Hello, and thank you for yet another fascinating question. I have no experience with anticoagulation in association with the ketogenic diet in seizure disorders. A literature search reveals a […]

Anticoagulant Therapy

Rivaroxaban Measurement by Anti-Xa

Dave McGlasson forwarded Samama MM, Contant G, Spiro TE, Perzborn E, Le Flem L, Guinet C, Gourmelin Y, Rohde G, Martinoli JL. Laboratory assessment of rivaroxaban: a review. Thromb J. 2013;11:11–18, linked below. The article supports measuring rivaroxaban with the chromogenic anti-Xa assay using rivaroxaban calibrators and controls, and concedes that the prothrombin time (PT) in […]

Anticoagulant Therapy

Change in Actin FS Sensitivity

Here is a new message from frequent contributor Joyce Low at St. Vincent’s in Sydney. “Our lab has been using Actin® FS since 2007. For us, different lot numbers have been reasonably similar in terms of the reference interval 25–35 s on Stago instruments and heparin therapeutic interval of 50–75 or 80s determined by anti-Xa assay. In […]

Anticoagulant Therapy

Does Lipitor Affect INR?

I received this August 6 note from Prof. Emeritus Bernadette Rodak, Indiana University Clinical Laboratory Science program. Prof. Rodak responds to questions posted by patients to the ASCLS Consumer Web Forum and passed this along for comment: “I have a question from a patient whose INR suddenly jumped to over 7 when he started atorvastatin (Lipitor®). I found […]

Anticoagulant Therapy

Kcentra or Profilnine?

From Jane Bossart: Any thoughts on whether Kcentra® (Behring CSL) will be better than Profilnine® (Grifols)? It seems there have been no head to head comparison yet. Hello, Jane, and thank you for your question. Although non-activated prothrombin complex concentrates (PCCs) and sometimes recombinant activated factor VII have been used off-label in conjunction with vitamin K […]

Anticoagulant Therapy

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George Fritsma is a medical laboratory scientist, educator, and author. George is a member of the International Society on Thrombosis and Hemostasis, the International Society for Laboratory Hematology, and the American Society for Clinical Laboratory Science.

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