Blood Draw & Tubes Flashcards
True or False: Whole blood will clot if left in the tube for over 30 minutes.
False
What is added to plasma to prevent clotting?
Anticoagulants
How long will blood take to clot? What product is left behind?
20 - 30 minutes
Serum - blood cells trapped in a mesh of fibrin
What is the name of the formation of WBCs and platelets in centrifuged test tube?
Buffy Coat
True or False: Coagulation proteins are still present in the plasma even after it has been spun down.
True
What is the liquid portion of clotted blood samples? Which coagulation protein is it lacking?
Serum; lacks Fibrinogen
Venous blood samples make up what percentage of specimens submitted to the laboratory?
80%
What procedure is performed when a venipuncture is contraindicated? What are some examples of patients they may be indicated for?
Capillary sample; Babies, small children, burn victims
***Capillary sample is composed of a mixture of arteriole, cap and venous blood in addition to interstitial and intracellular tissue.
What does SST stand for in regards to blood tubes? What is it and what is its purpose?
Serum Separator Tube
It is an inert polymer barrier gel; once centrifuged it will act as a barrier between serum and clotted cells.
Which color tube(s) fall into draw order group 1?
Light Blue
Which color tube(s) fall into draw order group 2?
Plain red/red and gray SST
Yellow
Green
Which color tube(s) fall into draw order group 3?
Purple/Lavender
Black
Which color tube(s) fall into draw order group 4?
Gray
What reagent does a light blue tube contain? What is its purpose?
Sodium Citrate; Anticoagulation
What is the yield of a light blue tube?
Citrated Plasma
What are the laboratory uses for a light blue tube?
Coagulation study
True or False: A light blue tube must be filled to a 1:7 ratio of sodium citrate to blood.
False, it must be a 1:9 ration. Any less will be considered a short-draw and discarded.
What color tube may contain Thrombin? What is the role of the Thrombin in this tube?
Red / Red and Gray SST
Thrombin acts as a clot activator
What color(s) of tube(s) are used to yield Serum?
Red / Red and Gray SST
Yellow
What is the laboratory use for a red tube blood draw?
Chemistry and Serology
What is the reagent in a yellow topped tube?
Acid Citrate Dextrose(ACD)
What is the laboratory use of a yellow topped tube?
HLA and paternity testing
Which colored tube(s) CANNOT be used for Calcium, Sodium or Potassium testing? Why?
Purple/Lavender and Black
It contains EDTA
What is the purpose of the EDTA reagent contained in purple/lavender and black tubes?
Purple/lavender and black tubes yield Plasma, therefore we do not want them to clot. EDTA will chelate the calcium(which is required for coagulation) in the sample, thus not allowing it to clot.
