Two New Cheat Sheets

Cheat Sheets for April and May of 2013 are now posted. Take advantage of these summaries as an introduction to our most recent posts. The Cheat Sheets will also be appearing in your mailbox in due course. Geo.

Some Significant Retirements

This post is not directly related to hemostasis, but I want to highlight the retirements of three esteemed colleagues, Bernadette F. (Bunny) Rodak, MS MT (ASCP) SH, Professor of the Clinical Laboratory Science Program, Jacqueline H. Carr, MS MT (ASCP) Laboratory Manager, Department of Pathology and Laboratory Medicine, both at Indiana University Health in Indianapolis; and Carol McCoy, PhD, MLS (ASCP) CM, Director of the Medical Laboratory Science Program at Fairview Health Services, St Paul, MN. Bunny and Jackie are the co-authors of the iconic Clinical Hematology Atlas, published by Elsevier, and now in its 4th edition, 2013. Bunny and I have also served as co-editors and authors of Hematology, Clinical Principles and Applications, also published by Elsevier, now in its 4th edition, 2012, and preparing for its 5th edition. I have also had the opportunity to work together with Carol as co-members of the American Society for Clinical Laboratory Science, where we served together on the Hematology/Hemostasis Scientific Assembly, as editors of the ASCLS Journal, Clinical Laboratory Science, and most recently as trustees for the ASCLS Education and Research Fund, Inc, a source of graduate student and member research grants. I look forward to continued professional initiatives with Bunny, Carol, and Jackie, my colleagues and friends.

Adjust Citrate in Severe Anemia?

From Barbara Caufield, Good Samaritan Hospital: We adjust the Na citrate volumes in coagulation tubes when the hematocrit (HCT) is > 55%. Do you recommend correcting for low HCTs? Can you tell me what formula you would use for a low HCT? At what HCT percentage do you recommend adjusting the sodium citrate? Thank you!

Read more »

Sodium Citrate: 3.8%?

Here is a question from Iratxe Paz, Iline Microsystems: Has sb reported shorter clotting times when using 3.8% (0.129M) sodium citrate tubes than 3.2% (0.109M) tubes? literature and the logic says the opposite.

Read more »

Pradaxa Measurement: An Oxymoron?

George sent this message to Dr. David Alter, Spectrum Health System, Grand Rapids, Michigan (once named Butterworth Hospital), regarding a question he posted on MEDLAB-L on Monday, June 10, asking, “Isn’t monitoring Pradaxa an oxymoron?”:

“Hi, Dr. Alter. I subscribe to MEDLAB-L and just saw your post regarding Pradaxa measurement. May I post your question and some discussion of new oral anticoagulant measurement on my web site, The Fritsma Factor? By the way, I’m a graduate of the old Butterworth School of Medical Technology, back when the earth was still cooling.”

Read more »

What is an RUO/IUO?

We’ve had several posts about measuring the new oral anticoagulants, the most pressing concern for coagulation laboratories around the world as they are confronted with the need to determine the presence and levels of dabigatran, rivaroxaban, apixaban, and soon, edoxaban. Though pharmaceutical distributors reassure us there is no need for monitoring, we are confronted with patients who have renal insufficiency, who are bleeding from a possible, but undefined overdose, concerns for non-compliance, or patients with potential coagulation imbalances as are documented in cancer, liver disease, during pregnancy, obesity, small body mass, chronic DIC, or those suffering a current thrombotic episode. Especially troublesome for lab scientists are clinical efforts to screen for coagulopathies while patients are on anticoagulants, a recurring issue in which lab scientists attempt to integrate skewed results.

Read more »

Rx Level for Dabi?

Dave McGlasson, hemostasis researcher at Wilford Hall USAF Medical Center in San Antonio, is engaged in a large-scale dabigatran measurement project. He reports that a prominent Midwestern medical center uses 45–95 ng/mL as their therapeutic range, using the plasma-diluted thrombin time (DTT, Hemoclot® direct thrombin inhibitor). In the article in Europace (2013) 15, 625–51 (posted May 9, 2013 on Fritsma Factor) the authors, using the DTT, say that bleeding is documented when the result is ≥ 200 ng/mL (~65 seconds) at trough. Trough (nadir) is defined as just before the next dosage, or 12 hours after the previous dose. In Mr. McGlasson’s study the range on subjects who have their blood drawn at different times of the day (convenience sample) is ~0–700 ng/mL using the DTT. Results are similar when measuring with the Ecarin chromogenic assay, prothrombinase-induced clotting time (PiCT) assay and the partial thromboplastin time (APTT, PTT). Mr. McGlasson asks, we are now working on establishing a therapeutic range, what are other sites seeing? Please provide your answer in the comments section below.

PNP Test for LA

Here is a challenging technical question about the platelet neutralization procedure (PNP) for identification of lupus anticoagulant (LA) from Charlene Bierl MD, PhD Director of the Clinical Laboratory. Cooper University Hospital, Camden, NJ. Dr. Bieri’s question was originally addressed to Drs. Marisa B. Marques and Jill Adamski and to specialty technologists Laura Taylor and Patti Tichenor at the University of Alabama at Birmingham Hospital Department of Laboratory Medicine. Following is a lengthy dialogue:

Read more »