Lab Homework #11- Hemostasis and Platelets

Define thrombocytosis

Thrombocytosis is when there is an abnormally high number of platelets in the blood and this can lead to thrombosis (increase in platelet count)

What are the 3 components of Virchow's Triad IN ORDER?

Damaged blood vessels, blood flow interrupted, and coagulation is initiated

Congenital coagulopathies are more commonly seen than acquired coagulopathies

False

Which breed of dog has an increased prevalence of von Willebrand's disease and is often referred to as the "poster child" for this disease?

Doberman Pinscher

What organ creates the majority of coagulation factors?

Liver

EDTA blood tube

Preferred blood tube for assessing platelet counts

Heparin blood tube

Preferred blood tube for assessing plasma chemistry profiles

Sodium citrate blood tube

Preferred blood tube for assessing the majority of platelet function tests

What is the process of hemostasis?

Cessation of bleeding through blood vessels via vasoconstriction, platelet activation, coagulation, fibrinolysis, and wound healing.

Which plasma protein is necessary for platelet aggregation?

Fibrinogen

What is the difference between petechiae and ecchymoses bruising?

Petechiae are small pinpoint sized dots that are caused from capillaries breaking under the skin but Ecchmoses are larger in size and are caused when there is a rupture of larger blood vessels (venules). Both are bruising of the skin but Ecchmoses are larger.

Define thrombocytopenia

thrombocytopenia is a decrease in platelet production (decrease in platelet count)

Coagulation

intrinsic and extrinsic pathway intersect into the common pathway and lead to clot formation. Component of secondary hemostasis.

Activated clotting time (ACT)

Assesses intrinsic and common coagulation pathways. Healthy clotting times is less than 95 seconds in canines and 165 seconds in felines.

Fibrinogen

Plasma protein produced in the liver that is a component of primary hemostasis. Increases in the plasma can indicate inflammation. 

Fibrinolysis

destruction of blood clots

Prothrombin time (PT)

coagulation pathways. Considered prolonged if >30% longer than control. 

Platelet activation

Required for blood clot formation and hemostasis. Component of primary hemostasis.

Partial thromboplastin time (PTT)

Assesses intrinsic and common coagulation pathways. Considered prolonged if >30% longer than control

Platelet disorders can be both congenital and acquired.

true