coagulation and platelet disorders

Question 1

what is coagulation initiated by?

Answer 1

cell injury, exposure of blood to collagen

Question 2

what clotting factors are:

Answer 2

made by the liver

Question 3

all clotting factors are what in the blood?

Answer 3

enzymes, in inactive forms

Question 4

activation of clotting factors is what?

Answer 4

a cascade

Question 5

thrombin leads to what?

Answer 5

fibrinogen

Question 6

fibrinogen leads to what?

Answer 6

fibbing molecules (bind together into long fibrinous strands)

Question 7

what is thromboembolic disease?

Answer 7

the abnormal formation of blood clots (95% of heart attacks)`

Question 8

what are the factors of thromboembolic disease?

Answer 8

triad of Virchow

Question 9

what are the triads of Virchow?

Answer 9

-loss of vessel wall integrity(endothelial injury, plaque formation)
-change in the blood constituents which increase the probability of coagulation (platelets, clotting factors, viscosity)
-abnormalities in blood flow (decreased flow rate and turbulent flow in arteries-eddies)

Question 10

what are the treatments for thromboembolic disease?

Answer 10

heparin
Coumadin
break down existing clots:
-streptokinase
-urokinase
-TPA
-asprin

Question 11

what does heparin do?

Answer 11

inhibits the formation of thrombin with antithrombin

Question 12

what does Coumadin do?

Answer 12

decreases the synthesis of prothrombin (needs closely monitored. to prevent excess bleeding)

Question 13

what does streptokinase do?

Answer 13

allows strep bacteria to degrade blood clots

Question 14

what does urokinase do?

Answer 14

naturally made by the kidneys and degrades small blood clots

Question 15

what does TPA stand for?

Answer 15

tissue plasminogen activator (short 1/2 life)

Question 16

what does aspirin do?

Answer 16

decreases platelet adhesiveness which inhibits clot formation

Question 17

what is disseminated intravascular coagulation (DIC)?

Answer 17

the pathological activation of the coagulation process leading to wide spread clot formation and active bleeding

Question 18

how does active bleeding occur in DIC?

Answer 18

active bleeding is a result of clotting factors and platelets being all used up and the body being unable to replenish them adequatley

Question 19

how is clotting is initiated by in DIC?

Answer 19

endothelial damage- bacterial toxins(DIC freq. occurs with septic shock)
major tissue damage-trauma and burns
obstetric complication-placenta rich in thromboplastin (rupture, retained placenta and fetus)
cancer-destroys surrounding tissues, release of thromboplastin,clotting

Question 20

what does DIC cause?

Answer 20

clots form in microcirculation-impede blood flow-ischemia in capillaries-capillary rupture-active bleeding-organs can fail (kidney)

Question 21

what is the treatment for DIC?

Answer 21

transfusion
platelet replacement
heparin
antithrombin 3(neutralizes thrombin)

Question 22

what Is thrombocytopenia?

Answer 22

the decreased # of circulating thrombocytes

Question 23

what are the causes of thrombocytopenia?

Answer 23

increases destruction of use
decreased production
increased sequestering in the spleen (splenomegaly or liver cirrhosis)

Question 24

what are the consequences of thrombocytopenia?

Answer 24

bleeding in small vessels
if the spleen in removed or contracts-minute clots in the small vessels break leading to hemorrhage

Question 25

what is impaired hemostasis in these coagulation and platelet disorders?

Answer 25

inability to promote coagulation and development of a stable fibrin clot

Question 26

what is the cause of thrombocythemia