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An Experimental Oral FVIII Mimetic

Click here in Hemostasis Today for a brief discussion of a developing phase 1 oral FVIII mimetic: Wolfgang Miesbach: Jan Astermark at the BIC 2025 presented Potentially the First Oral FVIII Mimetic Treatment for Hemophilia A.

Bleeding Disorders

October 2025 Cheat Sheet

Click here to read your October 2025 Fritsma Factor Cheat Sheet. Your personal copy will arrive soon in your inbox. If you aren’t receiving the “push” Cheat Sheet, please complete the form on the right. While you’re there, please give your answer to this month’s Quick Question. Both the Cheat Sheet and Fritsma Factor are […]

October 2025 QQ: Reporting Assay Uncertainty Data

Please refer to our August 29, 2025 discussion, “Hemostasis Assay Statistical Variation.” In this post, we linked the article, Mullier F, Gouin-Thibault I, Meijer P, et al. Time to integrate measurement uncertainty in method comparison and interpretation of hemostasis laboratory assays. Res Practice Thromb Hemost 2025: 9, https://doi.org/10.1016/j.rpth.2025.102993. The authors contend that we should report uncertainty […]

Quick Question Archive

September 2025 QQ: Viscoelastometry Discussion

Our September 2025 Quick Question asked, “What viscoelastometry device is employed at your facility?” A modest group of thirteen participants answered… TEG 6s: 4 (31%) TEG 5000: 2 (15%) ROTEM: 5 (39%) Sonoclot: 0 Hemosonics Quantra: 2 (15%) The TEG 5000 was developed in 1948, and the Sonoclot in 1975; both represent the pioneering phase […]

Quick Question Archive

Estrogen and Progesterone

Here is a question from my (Geo) friend and colleague, Kathryn Doig, MLS, PhD: “We all know that some women are prone to clots with both birth control hormones and menopausal hormones, but I want to understand why. I found a good review article with a reference (I have since lost) that showed an increase […]

Incubation to Inactivate Efanesoctocog Alfa Prior to Inhibitor Bethesda Titer

Click here for an open-access letter that indicates the need to inactivate plasma EHL FVIII efanesoctocog alfa (Altuuviiio®; Altuvoct®) before performing a Bethesda titer to measure anti-FVIII inhibitor: Bowyer A. Is incubation for 30 minutes at 56°C sufficient to fully inactivate efanesoctocog alfa? Haemophilia. 2025. doi: 10.1111/hae.70137. PMID: 40985057. The findings provide a recommended incubation […]

Bleeding Disorders

Does Chewing Gum Affect Fasting Blood Specimens?

On September 23, 2025, friend and colleague Dave McGlasson had a fasting blood specimen drawn. The collector noted that he was chewing gum and explained that the gum, although sugar-free, could affect the results. McGlasson messaged, “Chewing sugar-free gum should be avoided before a fasting blood draw because it can elevate certain blood levels, including […]

Specimen Management

WFH Fibrinogen Disorders Booklet

Click here for a recent WFH booklet, What Are Fibrinogen Disorders?

Bleeding Disorders

Reprise: In Vitro DOAC Removal

At the request of the Annals of Blood editor, here is a link to our 2020 article on in vitro DOAC removal agents, which has attracted >5000 page views: McGlasson DL Fritsma GA. In vitro detection and removal of direct oral anticoagulants from patient plasma specimens. Ann Blood 2020;5:25 | http://dx.doi.org/10.21037/aob-20-16. The article was first […]

Anticoagulant Therapy

Elevated PT/INR Case

This question recently appeared in the Diagnostic Health Equity site, managed by Tamara Lobban-Jones. “My doctor said my PT/INR was a little high. What does that actually mean for me, and should I be worried about bleeding more easily? I’ve been on a blood thinner for a while, but my PTT keeps coming back different […]

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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