Exam 2 Flashcards
(108 cards)
What is hemostasis?
the ability of the body system to maintain the integrity of the blood and blood vessels
What are the four main steps to achieve hemostasis?
primary, secondary, fibrinolysis, and restoration of vessel patency
What is primary hemostasis?
transient vasoconstriction with formation of platelet plug
What is secondary hemostasis?
coagulation to form mesh of fibrin
What is fibrinolysis?
removal of platelet/fibrin plug (thrombus retractin)
What is restoration of vessel patency?
tissue repair at damaged site
What players are involved in primary hemostasis?
release of endothelians by injured endothelial cells causes local vasoconstriction
What players are involved in secondary hemostasis?
series of enzymatic reactions involving clotting factors which leads to the formation of fibrin mesh which stabilizes the platelet plug
Where are most coagulation factors produced?
the liver
Where is factor III produced?
endothelial cells
Where are von Willebrand factors produced?
within endothelial cells (blood vessels / bone marrow
Which factors require vitamin k for activation?
II, VII, IX, X
Which of the vitamin k factors has the shortest half-life?
factor VII - 5 hours
Which factors are involved in the intrinsic pathway?
factors XII, XI, IX, VII
Which factors are involved in the extrinsic pathway?
factors III and VII
Which factors are involved in the common pathways?
factors X, II, I, XII
Define thrombocytopenia.
decrease in platelet count
Define thrombocytosis.
dysfunctional platelets
Define thrombocytopathia?
low blood platelet count
What are the 3 general ways to have thrombocytopenia?
decrease in production
increase in consumption
sequestration
(don’t make it, spend it, or something takes it)
What are 2 main causes for thrombocytosis?
reactionary
primary
What does the reactionary cause for thrombocytosis?
chronic inflammation
iron deficiency
bushings
What does the primary cause for thrombocytosis?
megakaryocytic leukemia
What does MPV stand for?
mean platelet volume