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Altitude and Vacuum Tubes

Mary Lou Turgeon, EdD, MLS (ASCP) of Mary L. Turgeon and Associates, posted this question about altitude and blood collection on CLSEduc, the Clinical Laboratory Science educators’ bulletin board on September 1: How do those of you living in the Mile High City or other high altitudes deal with the effect of altitude on the blood […]

Case Study: Protein C and S

A 17-month old child suffered a stroke in July of 2010. The results of a specimen collected ten days after the event showed that his protein C and protein S activities were 54% and 40%. Reference intervals for a child over 1 year old are the same as adults: 65% to 140% for protein C […]

Heparin-induced Thrombocytopenia: The PF4 Assay

I had a question on HIT testing back in early August that I lost the thread on, but here is a comment on the HIT assay from Dana Haas, St. Luke’s Episcopal Hospital, Houston, TX that I think answers the question. This came, with Dana’s permission, from Pat Letendre’s Medlab list. Initially when my institution started doing the PF4 […]

Thromboelastograph

Vilas Hiremath posted aThromboelastograph (TEG) question in a recent response to a 2008 post. I’m concerned the message may be buried, so am linking to it here. I also wanted to provide this normal TEG tracing for anyone who may be unfamiliar with the instrument.

Compensating for Hematocrit

From Don Kong, PM Core Lab Supervisor Children’s Memorial Medical Center We have a child with a WBC count of 600,000/mcL. The hematocrit with only the RBC mass is 22.8%. However, if the WBC mass + RBC mass is taken into account, the hematocrit jumps to 70%. There is only a small portion of plasma […]

Quick Question: Mixing Studies

Here are the results from our July Quick Question: When do you perform partial thromboplastin time (PTT) mixing studies? a. Any non-heparin PTT that is prolonged beyond the upper limit of normal: 43% b. Any non-heparin PTT that is substantially prolonged beyond the upper limit of normal: 15% c. We solicit clinical information before performing […]

Frozen V. Fresh Pooled Plasma

Dear George, What is the effect of a frozen sample and frozen normal pooled plasma on factor VIII inhibitors. Is fresh normal pooled plasma a good option? Please comment. Vilas Hiremath, Bangalore India Hello, Vilas Hiremath, and thank you for your question. Frozen reagent pooled platelet poor plasma, such as Precision BioLogic’s CryoCheck Normal Reference Plasma is assayed […]

Reduced Platelet Response

Here is a message from Crystal Azevedo at Eastern Maine Healthcare: Hi George, Is an abnormal platelet response to low-dose ADP a significant finding in the setting of an intracranial hemorrhage? Also, the epinephrine-induced aggregation was somewhat sluggish, but not markedly abnormal. The testing was performed 6 months following the hemorrhagic event. Thanks for your […]

Pseudothrombocytopenia

From Jo-Ann Luy: What percentage of specimens with pseudothrombocytopenia caused by EDTA-dependent platelet satellitosis is resolved by collecting in a sodium citrate tube? Jo-Ann Luy Satellite Laboratory Services Redwood City, CA Dear Jo-Ann Luy, I’ve never seen data expressing a percentage, perhaps some of our participants have an answer. Platelet satellitosis in EDTA is relatively […]

AACC Poster: P2Y12 Blockade

The following poster will be presented Thursday, July 29, 2-5 PM at the AACC annual meeting: p2y12-receptor-blockade If you have any posters or platform presentations you would like me to post here, please send an e-mail to [email protected]. Thank you.

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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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