Haemostasis

Question 1

What are the 3 stages of haemostasis? ( briefly describe )

Answer 1

-Primary -formation of platelet plug
-secondary - formation fibrin
-fibrinolysis - fibrin clot dissolves

Question 2

What disorders might you see of primary haemostasis (clinical sign , tests) ?

Answer 2

disorders
-thrombocytopenia - reduced platelets
inherited
aquired - immune mediated , decrease production

-thrombocytosis - increase platelets
neoplasia
drugs
secondary to inflammation ,neoplasia , GI disease

clinical sign
-petechiae

tests
-platelet count
-Buccal mucosal bleed time
-VWF-antigen ( von willebrand disease)

Question 3

Name some disorders of secondary haemostasis .

Answer 3

-inherited - haemophillia A ( factor VIII) , haemophillia B (Factor IX ) , Factor XII deficiency in cats
-acquired - anticoagulant rodenticide toxicosis( inhibit vitamin K - some clotting factors are vitamin K dependant ) , metabolic disease

Question 4

Clinical signs seen with secondary haemostasis problems

Answer 4

-hypocoagulability -haematoma, haemorrhage
-hypercoagulability - thrombosis

Question 5

Tests for secondary haemostasis problems

Answer 5

• prothrombin time
  -activated partial thromboplastin time
  -fibrinogen ( particularly horses ) - using modified thrombin clot time

Question 6

What is disseminated intravascular coagulation ? DIC

Answer 6

uncontrolled intravascular thrombus formation and breakdown