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Mixed DOACs and the DOAC Clotting Time Test

In a January 2023 letter to the editor, available from the publisher or your library as Exner T, Ellwood L, Dangol M, Favaloro EJ. Mixing factor Xa and thrombin inhibiting direct oral anticoagulants produces a synergistic prolonging effect on most clotting tests. Int J Lab Hematol. 2023 Feb 21. doi: 10.1111/ijlh.14043, investigators examined a DRVVT-based […]

Anticoagulant Therapy

March, 2023 Cheat Sheet

Hello, all subscribers, here is your March 2023 Cheat Sheet. Your personal Cheat Sheet will arrive in your email within a few days. Enjoy!

March 2023 Quick Question: Apixaban Reversal

Our March 2023 Quick Question addresses DOAC reversal and asks, “Which reversal agent is effective in managing apixaban overdose?” Please give us your best selection and add your comments in our Comments section below this post. The question will be available through March 31.

Anticoagulant Therapy

February, 2023 Quick Question: VWF Activity Assays

Our February 2023 Quick Question, “What VWF activity assay do you use?” attracted 32 responses. Here are the results: Automated VWF:RCo: 12 [38%] VWF:RCo: 10 [31%] VWF:GP1bR: 3 [9%] VWF:GP 1bM: 4 [13%] VWF:Ab: 2 [6%] VWF:CB: 1 [3%] Although the aggregometer-based ristocetin cofactor activity assay [VWF:RCo] is criticized for poor reproducibility, with interassay CV […]

Bleeding Disorders

Spinal Cord Stroke

On February 26, 2023, a Fritsma Factor participant asked about a relative’s diagnosis of spinal cord stroke. Spinal cord stroke is rare, 0.3–1% of all strokes. I’ve attached a review article, Romi F, Naess H. Spinal cord infarction in clinical neurology: a review of characteristics and long-term prognosis in comparison to cerebral infarction. Eur Neurol. […]

Arterial Thrombosis

February, 2023 Cheat Sheet

Hello, I [Geo] have attached our February 2023 Cheat Sheet here, please take a peek, or await your personal email copy coming soon.

January, 2023 Quick Question: Tranexamic Acid

Our January 2023 Quick Question asks, What is the target of the anti-hemorrhagic agent tranexamic acid? For this question, the only correct answer is fibrinolysis. Here are the responses from our 57 participants… Factor V: 5 [9%] Factor XIII: 5 [9%] Fibrinolysis: 40 [70%] Prothrombin 4 [7%] Activated protein C 3 [5%] This QQ is […]

Quick Question Archive

VWF Activity Assay

Preliminary to our February 2023 Quick Question, here is a detailed January 2023 CAP Today article entitled “Ins and Outs of von Willebrand Factor Activity Assays.” In addition to the time-honored, but imprecise optical aggregometry-based von Willebrand Ristocetin Cofactor [VWF:RCo] assay, we now have these activity assays that, except for VWF:RCo, function without reagent-platelets… VWF:RCo: […]

Bleeding Disorders

Prehospital Transfusion

Here is a provocative article from the December 2022 issue of CAP Today that addresses the benefits and barriers to offering pre-hospital transfusions in trauma situations: Prehospital Transfusions, CAP Today, December 2022.

Bleeding Disorders

Precision BioLogic Chromogenic FIX Assay Cleared by the FDA

Congratulations to our sponsor, Precision BioLogic Inc., as their CRYOcheck chromogenic factor IX assay was cleared by the US Food and Drug Administration on January 5, 2023. Click here for PBI’s news release. and click “Factor IX Testing and Introduction to CRYOcheck Chromogenic Factor IX” to register for our February 1 webinar featuring special guest […]

Coagulation Factors

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George Fritsma is a medical laboratory scientist, educator, and author. George holds faculty appointments with Rutgers University and Michigan State University, and is a member of the International Society on Thrombosis and Hemostasis, American Association of Clinical Chemists, and American Society for Clinical Laboratory Science.

Cheat Sheets from George

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