Specimen Management

ED Specimen Hemolysis

George has been corresponding with friend and colleague, Dennis Ernst, MT (ASCP), Director, Center for Phlebotomy Education about the prevalence of hemolyzed specimens from the Emergency Department (ED) compared to hemolysis rates from other units. Dennis and George agree hemolysis is related to the practice of collecting laboratory blood specimens at the time the nurse […]

Specimen Management

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

Platelet Clumps in Citrate Tube

Dear Fritsma Factor, I am a hematopathology fellow evaluating the following patient for thrombocytopenia. History and laboratory results are listed in detail below. We have encountered a situation where the patient develops platelet clumps within citrate tubes but not in EDTA. I have found only limited information regarding this phenomenon and was wondering if anyone […]

Bleeding Disorders

Specimens with Hematocrit >55% Reprise

On September 12, 2016, Michelle Fahs MT (ASCP) asked about how to prepare tubes with the proper volume of anticoagulant for people whose hematocrit exceeds 55%. Here is a question from Sandy Odegaard asking about the correction formula’s derivation: Hi George, BD could not explain where the conversion factor for calculating the appropriate sodium citrate […]

Specimen Management

Correction Factor for ACD Solution

On September 28, 2016, Julia Hill asked, “Is there a standard calculation for using ACD tubes?” Her comment was appended to a 2009 entry describing HELLP syndrome, so it may have been buried deep in our database. George assumes Julia’s question relates to platelet satellitosis, which results from the action of an immunoglobulin potentiated in […]

Platelet Function Testing

Acceptable Coagulation Test Specimens

From Lauren Ball: Do you suggest that most labs use a 4 hour rule for specimen acceptability? We offer PT, PTT, fibrinogen, D-dimer, and anti-Xa tests. PTTs and Anti-Xa tests may need to be performed within 2 hours but the manufacturer’s guidelines suggest that a specimen is good for up to 8 hours for tests […]

Specimen Management

Platelet Counts from Citrate Tubes

Here is some correspondence between Estelle Ninnemann at ACL Laboratories, and Dennis Ernst, at the Center for Phlebotomy Education, Inc. From Estelle, “In our laboratory, phlebotomists collect sodium citrate (blue top) tubes when a patient is known to have a history of platelet clumping. The sample is collected and sent with the lavender top tube […]

Specimen Management

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

Whole Blood PTTs

From Kirk Guyer, Cascade Technologies: There are whole blood PTT (APTT) assays and there are citrated platelet poor plasma (PPP) PTT assays. What happens in a PPP PTT assay if there are platelets present? Does the PTT result shorten? Can platelets shorten the PTT result in a whole blood PTT assay? I ran a PTT […]

Bleeding Disorders

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

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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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