Hemostasis

Question 1

CLOT BUSTERS

Answer 1

activate plasminogen (t-PA, u-PA, streptokinase), break down existing clots, do not work to prevent clots

Question 2

Argatroban and pradaxa

Answer 2

thrombin inhibitors

Question 3

Warfarin is reversed by

Answer 3

giving vitamin K

Question 4

Warfarin is SLOW bc

Answer 4

it only affects factors synthesized after drug administration, pre-existing factors are functional

Question 5

Warfarin mechanism

Answer 5

inhibits vitamin K dependent gamma-carboxylase (prothrombin, 7, 9, 10) impairs coagulation

Question 6

Gamma-carboylation of factors

Answer 6

vitamin K dependent, necessary for factors to bind Ca in order for activation

Question 7

Heparin

Answer 7

activates antithrombin to inhibit thrombin and Facto 10a, DOES NOT destroy existing clots

Question 8

Heparin-induced thrombocytopenia

Answer 8

<100,000 immune reaction

Question 9

Heparin can be neutralized with

Answer 9

protamine

Question 10

Aspirin

Answer 10

inhibits COX-1 and TXA2 production

Question 11

Platelet receptor inhibitor

Answer 11

GpIIb-IIa inhibit platelet from binding fibrinogen

Question 12

Fibrinolytic drugs

Answer 12

plasminogen activator drugs, act like tissue plasminogen activators t-PA, u-PA

Question 13

Presence of FDP and D-dimers

Answer 13

thrombosis

Question 14

Elevated homocysteine

Answer 14

inhibits thromomodulin, inhibits heparan sulfate activity, inhibits plasminogen and fibrinolysis (long coagulation and clot presence)

Question 15

Factor 5 Leiden

Answer 15

INCREASED thrombosis risk, resistant to proteolytic Protein Ca, remains active longer

Question 16

Protein C/S

Answer 16

Destroys 5a and 8a

Question 17

Protein C/S deficiency

Answer 17

thombrosis risk

Question 18

aPTT

Answer 18

time required to observe a clot when exposing plasma to negative charged surface - measure heparin activity

Question 19

Heparin

Answer 19

antithrombin activation (>1000X)

Question 20

antithrombin

Answer 20

protease inhibitor that irreversibly inhibits thrombin (high MW) and 10a (low MW)

Question 21

Antithrombin deficiency

Answer 21

thrombosis risk

Question 22

TFP I (Tissue Factor Pathway inhibitor)

Answer 22

protease inhibitor inhibits 7a and 10a no known deficiencies - fatal>?

Question 23

Hemophiliac hemarthroses

Answer 23

bleeding into joints

Question 24

Hemophiliac hematomas

Answer 24

bleeding into subQ CT and muscle

Question 25

Hemophilia effects same reaction

Answer 25

10->10a (intrinsic pathway) catalyzed by 9a and requires 8a as cofactor

Question 26

Thrombin

Answer 26

fibrinogen to fibrin, factors 5 and 8 to 5a and 8a, stimulates intrinsic pathway, stimulates platelet aggregation in primary hemostasis

Question 27

PT

Answer 27

time require to form a clot after tissue factor is added to plasma, monitors warfarin treatment

Question 28

Serin protease coagulation factors

Answer 28

prothrombin, 7, 9, 10 require vitamin K for gamma-carboxylation