TEST II. REASONING Flashcards
SECTION 3 (LAST PART)
why is the tissue factor pathway called the extrinsic pathway
Its because it is triggered by the release of tissue factor(TF), a protein that is not normally present in the blood but is expressed on the surface of cells outside the vascular system. Tissue factor is considered extrinsic to the blood clotting cascade because it is not a component of the blood itself.
Why admistration of massive amounts of whole blood produce temporary thrombocytopenia
Stored blood contains fewer or no platelets, platelets have a short life span so when massive amounts of whole blood are administered there is a dilution effect of the blood present in the patient and the transfused blood as a result there is temporary thrombocytopenia up until the bone marrow produces more platelets to compasate
Why is it that asprin containing analgesics may lead to profuse wound bleeding after dental extraction
Aspirin irreversibly inhibits an enzyme called cyclooxygenase, Which is necessary for platelet activation and aggregation. This reduces the ability of platelets to form a plug and stop the bleeding
why is it that normal vascular intima prevents bleeding and thrombosis
The intima is lined with endothelial cells that produce anti-thrombotic factors that inhibit platelet activation and blood clotting
