Unit 3 Flashcards
(30 cards)
What is whole blood comprised of, where is it found
Found in the vessels (circulates the body) (blood transports oxygen, carbon dioxide, nutrients, waste and hormones)
Comprised on RBCs, WBCs, platelets, plasma (proteins, waste products and ion)
What is plasma
The fluid portion of blood containing an anticoagulant in which formed elements are removed after centrifuging (unclotted blood)
Contains fibrinogen and other clotting factors and proteins
Normally clear and straw coloured
What is serum
The clear, straw coloured liquid portion of blood that does NOT contain fibrinogen or formed elements (clotted blood)
What tests must be run determines what about blood collection
Collection site, procedure and equipment
True or false
Samples should be collected before any treatments are started
True
Why just alcohol be allowed to dry from the skin before blood collection
If any of the alcohol is brought into the syringe while collecting, it can cause hemolysis to RBCs
True or false
You must remove the needle when transferring blood from a syringe to a vacutainer
True
What are some benefits of vacutainer systems
Reduces artifacts
Prevents the veins from collapsing
What is a serum collection tube (red top), what are they used for?
Does NOT contain an anticoagulant
Used to allow blood to clot to remove serum
Used for a large number of biochemical blood test or used for storage and shipment of histology samples, hair samples etc
NOT used for hematology tests
What are heparin tubes (green top) what are they used for?
Contain heparin as an anticoagulant (sodium, potassium, lithium or ammonium salt)
Used for biochemistry tests particularly when while blood is needed
Never used for differential blood film analysis
What is an EDTA tube? (Purple top) What are they used for
Contains Ethylene diamine tetra acetic acid (powdered or liquid) (sodium or potassium salt)
First choice for hematology tests
Almost consistent preservation of cell volume and morphological features
Must be mixed gently when blood is added (too much EDTA will nullify automated machine analysis)
NOT used for chemistry tests (EDTA and calcium will interfere with tests)
What are Oxalate and citrate tubes (blue top)? What are they used for
oxalates available in sodium, potassium, ammonium or lithium salts
Citrates available in sodium or lithium salts (also used for blood transfusions)
Interfere with clotting by binding with calcium
Interfere with chemistry tests
May need to be refrigerated
What are sodium fluoride tubes (grey top)? What are they used for
Used for preserving blood glucose in a sample (questionable effectiveness)
Interferes with many enzyme tests
What is a sure-sep or serum separator tube? (Red with black or grey mottled top -tiger top)
A variation of a red top tube, does not contain an anticoagulant
Contains a gel in the bottom of the tube to separate the cells from the serum when it is centrifuged (when spun, RBCs go under the gel)
Prevents cells from metabolizing analytes
What does the amount of sample collected depend on? How much should you collect gold standard)
Volume required for tests needed
Patient hydration status
Should collect enough to run the test 3 times (allows for technical errors, instrument failure, dilution of sample, etc)
How much volume of blood is serum/plasma in a healthy vs dehydrated patient
Healthy: approx 1/2 the volume of whole blood is serum/plasma
Dehydrated: half that ^ (1/4)
What does a blood collection tube need to be labelled with
Patient name/identification
Date and time
Sample type
Initials
Blood collected for CBC should be analyzed within _ hours of collection. If not possible what should be done?
1 hour of collection
Make a blood smear and refrigerate the tube
True or false
Blood smears should not be refrigerated
True
What temperature should blood be analyzed at
Room temp
(Remove from fridge 30 min before running a test)
Why should you never freeze blood
Causes cells to lyse
Using a vacutainer system, what types should be filled first? What about with a needle and syringe?
Vacutainer system: Serum tubes (no anticoagulant) (don’t want to contaminated the red top with anticoagulant from the other tubes)
Needle and syringe: anticoagulant tubes first (reduces risks of clots in anticoagulant tubes)
A chemical analysis of the blood is performed to evaluate electrolytes, proteins, enzyme levels and other analytes within the ___ portion of blood, usually on ___
Liquid, usually on serum
Why are fasted samples preferred
Glucose, urea, lipase and cholesterol may be affected if the animal has eaten recently
12 hour fasts are required for some tests
