Anticoagulant Therapy

More on ISTAT Versus PT/INr

Here is a Paul Riley, PhD follow up to Diane Treadway’s discussion and follow-up comment comparing the ISTAT INR to the central lab plasma-based PT/INR. From Dr. Riley, Stago-US. I don’t understand what is happening with the bivalirudin interference. According to Gosselin et al. (below) there should be minimal effect on the Stago PT (see […]

Anticoagulant Therapy

Collect Specimens After Dialysis

Here is a question from colleague, friend, and frequent contributor Larry Brace, PhD, Edward Hospital, Naperville, IL: Our (years-old) phlebotomy policy says to wait 4 hours after dialysis before venipuncture unless a doctor approves the draw. It makes sense but we can’t seem to find a reference. Can you suggest any? Also, is this policy pretty […]

Anticoagulant Therapy

Ottawa Blood Disease Center DOAC Survey

George is posting this survey invitation as a courtesy to the Ottawa Blood Disease center and encourages all physician Fritsma Factor participants to join the survey: Hello, You are being asked to participate in a research survey* that we have developed. Physician members from a variety of associations in Canada, the United States and Europe […]

Anticoagulant Therapy

Whole Blood PTs

From: Brancaccio Mauro, ICD-Partners, Italy. Is it possible and correct to do the PT on the sangueblood? Hello, Bancaccio Mauro. If I translate correctly, I will take sangueblood to mean whole blood (with thanks to Dave McGlasson for his assistance). Yes, the PT has been established as a whole blood assay using point of care […]

Anticoagulant Therapy

Heparin and Cell-free DNA

Here’s a challenging question from the ASCLS Consumer web forum: “I’m currently on 40 mg of Lovenox daily during my pregnancy. Can that alter the cell-free DNA test in any way? I take my meds at 10 every morning, should i take the blood test after my shot is due? I’m getting different answers from […]

Anticoagulant Therapy

The 100th Anniversary of Heparin 1916–2016

On behalf of Dr. Jawed Fareed, the Loyola University Chicago Office of Continuing Medical Education extends an invititation to the Heparin Centennial Symposium: Scientific and Clinical Developments and their Impact on the Understanding of the Pathogenesis of Thrombosis and Its Management. The conference will be held in the Center for Translational Research and Education on […]

Anticoagulant Therapy

Bangor Presentations

George was in beautiful Bangor, Maine, Monday, September 12, where he provided two presentations for regional medical laboratory scientists, sponsored in part by Dahl-Chase Diagnostic Services. Handouts for George’s talks are provided below. Please click or tap if you would like to have the handouts. Measuring the DOACs, Whatever Happened to the PT and PTT? […]

Anticoagulant Therapy

Rivaroxaban Causes False LAC Positive

George reviewed this question posted to the American Society for Clinical Laboratory Science Consumer Web Forum: “After DVT/PE helped by TPA/heparin and now on Xarelto 4 weeks, my first blood draw shows factor VIII 228%, DRVVT screen 126 sec, confirmation 61 sec, normalized ratio 1.96, but hex phase phospholipid normal range and antiphospholipid normal range. […]

Anticoagulant Therapy

Monitoring DOAC to UFH Change

Correspondence between Lawrence “Lance” Williams III, MD, University of Alabama at Birmingham (UAB) Hospital Special Coagulation Director and Michael Laposata, MD, University of Texas Medical Branch (UTMB) in Galveston Pathology Director: Dr. Laposata, I am curious if you might have some insight on an issue we are having at UAB. We have noticed an increase in patients […]

Anticoagulant Therapy

Anti-Xa Assays and Plasmapheresis

From Joni Noges at Virginia Mason Medical Center: Hi George, our pharmacy is wondering whether anti-Xa levels are affected by plasmapheresis, continuous renal replacement therapy (CRRT), or hemodialysis. For example, should we draw levels 30–60 minutes after the procedures? Thanks. Hi, Joni, I forwarded your question to Lawrence “Lance” A. Williams, II, MD, who manages […]

Anticoagulant Therapy

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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.

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