Hematology Coagulation Flashcards
What are thrombocytes
Platelets
T/F thrombocytes are not complete cells
True, except in non mammals
What is the purpose of thrombocytes
Essential in hemostasis. Cytoplasmic granules contain some clotting factors. 3 specific functions
What are the three specific functions of thrombocytes
Maintain vascular integrity
Platelets plug formation
Stabilization of hemostatic plug contributing to fibrin formation
What is hemostasis
The ability to maintain the integrity of blood vessels and fluids. Divided into 3 categories
What are the three categories of hemostasis, and what are they responsible for
Primary - formation of platelets plug
Secondary - formation of fibrin through coagulation cascade
Tertiary - formation of plasmin for clot breakdown
What are some coagulation tests
Buccal mucosal bleeding time (bmbt)
Activated clotting time (act)
Prothrombin time (pt)
How do you test for buccal mucosal bleeding time
Apply gauze tourniquet to upper lip. Spring loaded lancet to make a deep cut, wait to see how long until it stops bleeding
Average 1-5 minutes
Which test is the primary assay in testing platelets function
Buccal mucosal bleeding time
How do you perform activated clotting time
Use tube with diatomaceous earth. Collect 2ml blood with vacutainer. Place in warm water or incubator. Observe at 60s then 5s intervals for presence of clot.
Average 60-90s
How do you evaluate prothrombin time
Preformed by automatic analysers. Uses citrated plasma sample.
As average 6-20 seconds
T/F hemostatic defects can be congenital or acquired
True
What are three things that can be effected in a hemostatic disorder
Platelets, coagulation proteins, vasculature
What is the difference between first and second degree coagulation disorders
1st degree - inherited defect in production of coagulation factors. Rare
2nd degree - nutritional deficiency, liver disease, ingestion of certain medications
What are examples of hereditary coagulation disorders
Hemophilia A
Hemophilia B
Von Willebrands disease
What are examples of acquired coagulation diseases
Thrombocytopenia
Vitamin K deficiency
T/F hemophilia A is most common coagulation deficiency in dogs
True
T/F von Willebrands is the most common coagulation disorder in domestic animals
True
What blood tubes are anti-coagulants
Heparin. EDTA, oxalates, citrates
What blood tubes is used for transfusion medicine and clotting profiles
Citrates
T/F you can use heparin for differential blood smears
False. Interferes with WBC staining and causes clumping of WBC
What are heparin tubes used for
Plasma samples used in blood chemistry
