Specimen Management

Platelet Clumping in Sodium Citrate: Reprise

From Kathy Jacobs at Chronolog, Inc. Hi George, When a patient’s platelets clump in sodium citrate, is there another anticoagulant that can be used to allow LTA platelet aggregation testing? Thanx in advance, Kathy. Hi, Kathy, good to “hear” from you. You posted your question originally as a comment to a

Platelet Function Testing

Hemolysis and Heparin Anti-Xa

A message from “Danagah:” Hi, George, How would you handle a sample for a chromogenic heparin anti-Xa assay if a patient is experiencing in vivo hemolysis and you cannot obtain a sample that is not hemolyzed? Would it make a difference as to the degree of hemolysis as to even accepting the sample? We reject […]

Anticoagulant Therapy

PT Stability for Open Specimens

A new specimen question from Pam Owens, TriCore Laboratories: Hi George, this is a question with two parts. Given that a PT is stable for 24 hrs in the original tube with the top on (never removed)… 1. How long is the sample good once the top has come off? 2. If the plasma has been removed, […]

Specimen Management

Does Elevated HCT Affect PT/INR?

Hello Mr. Fritsma, I am a pharmacy student working in an internal medicine clinic where we manage patients on warfarin. We had a question come in about how an elevated hemoglobin and hematocrit, HGB/HCT can affect INR levels as the lab is stating that as long as this patient’s hemoglobin is elevated, her INR results […]

Specimen Management

More on PTT Specimen Storage Time

On November 1 I replied to a question from Joe Lamb, Columbus, GA about room temperature storage of specimens for partial thromboplastin time (PTT) assays that are sent to reference laboratories. Joe was concerned that his reference lab claimed PTT results were valid on specimens less than 24 hours old, whereas the CLSI Guideline H21-A5 sets […]

Anticoagulant Therapy

Normal Plasma Storage

Here is a seemingly simple request from Vicki Lanigan at Niagara Health, Ontario, Canada: “I am looking for a reference for storage of normal pooled plasma (NPP, pooled normal plasma, PNP).” Vicki, this one drove me back to the books and to the package inserts for distributors Precision BioLogic Inc and George King Bio-Medical, Inc to learn the shelf life for […]

Specimen Management

Faulty In Vitro Clotting in Myeloma

From Heidi Lawson: I was wondering if you had any information on why multiple myeloma (MM) patient specimens do not (at times or at all) spin down well in serum separator tubes (SST) or red top tubes. I called BD and they gave me a small excerpt of information stating that MM patients, due to myeloma […]

Specimen Management

Collecting Blood from Hemodialysis Patient

This practical question was sent to the ASCLS Consumer Web Forum over the weekend: Where would you draw blood from a hemodialysis patient to obtain an ACT? I was always taught to draw from venous port to ascertain the ACT in the system to prevent clotting and blood loss. Thank you for your question. As […]

Specimen Management

Can’t Separate Newborn Plasma

Dear George, One day old baby citrate sample, unable to separate plasma after centrifugation. Repeated with fresh sample, same problem. What is the cause? With regards, Vilas Hiremath, United Labs. Hello, Vilas, it is always good to hear from you. Does this mean no plasma layer appears after centrifugation? If so, perhaps polycythemia has made the […]

Specimen Management

Overfilled Tubes

I received a note from David Chance, Good Samaritan Medical Center, Corvallis OR, commenting that, unlike underfilled coagulation specimen (blue-closure) tubes; overfilling tubes, unless clots are present, does not affect coagulation results. Overfilling may occur when a specimen is collected by syringe and pushed into a tube. There is no comment on overfilling in CLSI H21-A5, […]

Specimen Management

Load more

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.

Cheat Sheets from George

Quick Question