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Yet More on the PT Mix

From Ali Sadeghi-Khomami: Hi George, I read Dave McGlasson’s paper with great interest. In brief, his case had the following results: PT 60s PT mix 57s PTT >100s PTT mix 87s PTT 2 h 37°C incubation >200s Platelet neutralization (PNP) Positive Kaolin clotting time (KCT) >200s DRVVT screen Positive DRVVT confirm Positive The article didn’t mention anything about a […]

What is PF3?

Each year George enjoys the opportunity to teach in Dr. Elaine Keohane’s graduate course, CLSC 5124, Advanced Hemostasis at Rutgers University School of Health Related Professions. Our students are experienced medical laboratory scientists from all over the world, and they bring a wealth of practical knowledge. Dr. Keohane is teaching a section on platelet physiology this week, and […]

Bleeding Disorders

More on Incubated PT Mixing Studies

Yesterday, January 21, 2014, I posted “

Incubated PT Mixing Studies?

From Lori Pinelli, Glens Falls Hospital: Hello George. Our current prothrombin time (PT) mixing time procedure only includes running the initial 1:1 mix along with the patient and the normal pooled plasma (NPP). Twice in the past year, I have been asked to perform an incubated PT mix in addition to the initial analysis. Both patients had […]

Rivaroxaban for ACS Denied

The FDA advisory committee yesterday, January 16, 2013, unanimously withheld clearance for rivaroxaban’s acute coronary syndrome indication. Details appear in today’sMedscape Oncology Heartwire headline. This is the third time that Janssen’s application has been denied for this indication. Rivaroxaban is cleared for stroke prevention in atrial fibrillation, thrombosis prevention following total hip or knee replacement […]

Anticoagulant Therapy

Rivaroxaban for ACS?

Announcement provided by Ali Sadeghi-Khomami, PhD; Research and Development Manager, Precision BioLogic Inc: In documents released ahead of an FDA advisory panel meeting on January 16, agency staff on Tuesday expressed skepticism that the data submitted by Johnson & Johnson demonstrate that Xarelto (rivaroxaban) is effective for treating acute coronary syndrome (ACS) in patients with a previous history […]

Anticoagulant Therapy

Rivaroxaban and Homocysteine

From our frequent contributor Crystal Azevedo, Eastern Maine Health System: Hello George, I am working up more patients taking the new directed oral anticoagulants (NOACs) for therapy. Is there a relationship between rivaroxaban and an elevated plasma homocysteine level? I have seen this more than once and I’m curious. Thanks! Hi, Crystal, this is an unexpected and […]

Anticoagulant Therapy

More on Mixing Studies and Incubated Control

From Kathleen Tobertga: Hello, We are having problems between sites with the results of our 2 hour normal pooled plasma (NPP) control (unmixed) for our mixing studies. Our site (the main lab) is getting an increased value for the PTT around 40 s, which we have researched and seems to be elevated due to heat labile […]

In Vivo Hemolysis

Irene Regan writes that despite doing major literature searches there seems to be no consensus regarding what coagulation results should be released when there is a suspicion of in vivo hemolysis such as in disseminated intravascular coagulation (DIC), when the samples are grossly haemolysed. Currently, Irene issues a fibrinogen (Clauss) and in this case she generally […]

Bleeding Disorders

Mixing Studies: Incubate Control Plasma?

From Louise Pleiss, MT (ASCP), Southcoast Medical Group: We recently changed our mixing study procedure to include rerunning of the normal pooled plasma (NPP) after a 2 hour incubation as one of our system controls, but we are having a difference of opinion about what should happen to the NPP. One site says that the partial thromboplastin […]

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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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