Factor Assays and Inhibitors

From Dee McMichael, Blood Bank Supervisor, All Children’s Hospital, St. Petersburg, FL: I was trying to post a question on your site but each time I received a connection failure. I will follow up with my IT department but thought I might be able to post my question in an email. (Dee, we apologize for the connection […]

Comments (1)

Factor Assays

Feb 21 2013

george

High HCT and PT, PTT, and D-dimer

From Barbara Robinson, MT (ASCP), Children’s Hospital of New Orleans, If a sample is tested for D-dimer, prothrombin time (PT) and partial thromboplastin time (aPTT, PTT), and the anticoagulant in tube has not been adjusted for high hematocrit (HCT = 60.8%), what tests would be invalid, and how would results be affected? Hi, Barbara, and thank you […]

Screening Assays

Fitzgerald Factor Assay

There is a helpful new “mdredjka” comment appended to our April 7, 2010 discussion on Fitzgerald Factor assays that was started by Peter Clement, then a student at Brigham Young University. Please take a look!

Factor Assays

Comparison of INR with FII, FVIII, and FX

From Dave McGlasson: George, Here is a potential answer for Kelly Townsend’s February 13 post, Factor II Assay in place of INR. Kelly is right. We did look at the chromogenic factor X and published that work a few years ago McGlasson DL, Romick BG, Rubal BL. Comparison of a chromogenic factor X assay with international normalized ratio […]

Comments (0)

Anticoagulant Therapy

Feb 13 2013

george

Factor II Assay in Place of INR?

From Kelly Townsend at TriCore Reference Laboratories: We have several patients in whom the INR does not appear to accurately assess their anticoagulation status. Since we do not have the chromogenic factor X assay on our menu, we’re interested in using the factor II activity assay based on a poster presented at THSNA meeting by the Univ of […]

Comments (0)

Anticoagulant Therapy

Feb 13 2013

george

More on PT Validation and AMR

Here’s an additional note confirming Denise Solieau’s February 12 discussion of PT validation and analytical measurable ranges (AMRs). Page 83 of the July 31, 2012 CAP survey references the value of AMRs in coagulation testing and includes this statement, “The new checklist requirements (meaning AMR) apply to hemostasis test methods that are calibrated and directly measure the concentration or […]

Comments (0)

Anticoagulant Therapy

Feb 12 2013

george

Validating the PT: AMR and CRR?

From Denise Soileau, Helena Laboratories: It is my understanding that calibration verification is not required for prothrombin time. Is AMR and CRR? If so how do you suggest this be accomplished? Hello, Denise, and thank you for your question. I’ve had some help from Larry Brace PhD, Edward Hospital, and Dave McGlasson MS, MLS, Wilford Hall USAF Hospital. It is true […]

Comments (0)

Anticoagulant Therapy

Feb 9 2013

george

Lupus Anticoagulant Panel

From Don Wahl, Sanford Health: What are the recommended tests to include in a lupus anticoagulant/antiphospholipid antibody (LA/APL) panel? Is there an antiphospholipid group that gives recommendations? Thank you, Don. Hello, Don, and thank you for your question. The group you need is provided in the title of this reference, and the reference provides the assays that […]

Mixing Studies

Bleeding After CABG: Heparin?

Here is a puzzling case sent by Crystal Azevedo: Hi George! I have a question for you from one of my pathologists. 24 hours after an uneventful coronary bypass procedure a 51 kg patient developed acute hemorrhage. A post-protamine thromboelastogram (TEG) on the day of surgery was completely normal. At the time bleeding occurred, the patient […]

Comments (4)

Anticoagulant Therapy

Jan 30 2013

george

Clopidogrel Efficacy

This question arrived last week in the American Society for Clinical Laboratory Science Consumer Forum: “I would like to know the differences between platelet aggregation testing and pharmacogenetic testing of CYP2C19 for clopidogrel. In 2010, the FDA issued a black box warning for clopidogrel in persons who are CYP2C19 poor metabolizers. I am very interested in what […]

Comments (0)

Antiplatelet Therapy

All Posts

Factor Assays and Inhibitors

High HCT and PT, PTT, and D-dimer

Fitzgerald Factor Assay

Comparison of INR with FII, FVIII, and FX

Factor II Assay in Place of INR?

More on PT Validation and AMR

Validating the PT: AMR and CRR?

Lupus Anticoagulant Panel

Bleeding After CABG: Heparin?

Clopidogrel Efficacy

George Fritsma MS MLS

Cheat Sheets from George

Questions or Comments?

Quick Question