Homeostasis Flashcards
How do the following anticoagulants work?
- Na2-EDTA
- K2-EDTA
- NaK-EDTA
They irreversibly bind calcium ions in the sample.
Which anticoagulants are used in haematology?
- Na2-EDTA
- K2-EDTA
- NaK-EDTA
What blood sample is used in biochemical investigations?
Mostly serum, without anticoagulants.
Sometimes plasma, with anticoagulants. (Heparin)
How does heparin work?
It enhances the binding of Antithrombin III which in turn blocks the conversion of fibrinogen to fibrin.
(Anticoagulant)
What are the side effects of heparin?
1) In fluid form it has a diluting effect and blocks ionised calcium over time.
2) The preferred lyophilised (freeze-dried), calcium-equilibrated heparin has a necrotising effect on white blood cells in vitro.
Which anticoagulant is used for testing blood clotting parameters?
Na2-citrate (3.8%)
How does Na2-citrate work?
It reversibly binds calcium ions in the sample.
Reagents for clotting tests contain calcium to start the clotting process
Which anticoagulant is used for biochemical parameters?
Heparin
What is the dosage of EDTA used?
1.5-2 mg EDTA + 1 mL full blood
What is the dosage of fluid heparin?
1 droplet heparin + 5 mL blood
What is the dosage of Na2-citrate for haemostasis evaluations?
Citrate:blood
1:9
What is the dosage of Na2-citrate in RBC sedimentation test?
Citrate:blood
1:4
Which anticoagulant is used for blood smears?
Na2-citrate (3.8%)
Which anticoagulant is used in blood transfusion bags?
Na2-citrate (3.8%)
Which anticoagulant is used for RBC sedimentation test?
Na2-citrate (3.8%)
Name a clotting activator.
Si-oxide or Si-gel
How is serum prepared?
A) Plain blood sampling tube.
B) Tube containing clotting activator.
What is a side effect of EDTA?
If a sample is stored in EDTA for more than 12 hours, blood cells swell.
What blood sample is used for haematology?
Anticoagulated plasma.
Na2-EDTA, K2-EDTA, NaK-EDTA