Haemostasis

Question 1

what does the endothelium of blood vessels produce?

Answer 1

heparins
TFPI - Tissue factor pathway inhibitor
thrombomodulin
NO
Prostacyclin

Question 2

what forms a clot?

Answer 2

platelets
vWF
Coagulation factors

Question 3

what makes sure that a clot remains confined to the site of injury?

Answer 3

natural anticoagulants

Question 4

what signals cause the resting platelets and coagulation factors to become activated?

Answer 4

abnormal surface

physiological activator

Question 5

first stage in vessel damage (use diagram)

Answer 5

Platelet adhesion to subendothelial collagen

von willebrand factor sticks to collagen and platelets

Question 6

what does the subendothelial collagen produce?

Answer 6

physiological activator

Question 7

what cell surface receptors are found of platelets?

Answer 7

ADP receptor
Epinephrine receptor
thrombin receptor

Question 8

what platelet glycoproteins are found on the surface?

Answer 8

VI
Ia/IIa/
Ib/V/IX
IIb/IIIa

Question 9

on platelets what does IIb/IIIa bind to?

Answer 9

fibrinogen

Question 10

on platelets what does Ib bind to?

Answer 10

vWF

Question 11

on platelets what does Ia/IIa bind to?

Answer 11

collagen

Question 12

name the roles of platelets in haemostasis

Answer 12

adhere
activation
aggregation
provide phospholipid surface for coagulation

Question 13

using a diagram describe the process of platelet adherance

Answer 13

see notes

Question 14

using a diagram describe the process of platelet activation

Answer 14

see notes

Question 15

using a diagram describe the process of platelet aggregation

Answer 15

see notes

Question 16

using a diagram describe the process of platelet coagulation

Answer 16

see notes

Question 17

vWF has binding sites for?

Answer 17

FVII
GPIb
Heparin
Collagen

Question 18

what factors are necessary for clotting?

Answer 18

F XII
XI
IX
VIII
X
Prothrombin
fibrinogen

Question 19

what factor is deficient in haemophilia B?

Answer 19

IX

Question 20

what factor is deficient in haemophilia A?

Answer 20

VIII

Question 21

describe the extrinsic pathway of fibrin formation

Answer 21

see notes

Question 22

describe the intrinsic pathway of fibrin formation

Answer 22

see notes

Question 23

name the most natural important anticoagulants

Answer 23

Antithrombin
TFPI
Activated protein C=protein S

Question 24

using a diagram describe the actions of TFPI in anticoagulation

Answer 24

binds to and inactivates VIIa and Xa

Question 25

using a diagram describe the actions of proteins C and S in anticoagulation

Answer 25

Va

Question 26

using a diagram describe the actions of AT in anticoagulation

Answer 26

``` thrombin XIa IXa VIIIa Xa ```

Question 27

using a diagram describe the process of fibrinolysis including natural inhibitors

Answer 27

endothelial cells produce plasminogen activators tissue plasminogen activator = tPA plasminogen has bridge which is cleaved by TPA to plasmin plasmin breaks the fibrin clot down degradation products d-dimer = fibrin broken down by plasmin natural inhibitors of plasminogen and plasmin a2-antiplasmin can be issue in liver transplantation which ends up excessive fibrinolysis therefore bleeding occurs

Question 28

using a diagram describe the MoA of aspirin

Answer 28

see notes

Question 29

using a diagram describe the MoA of clopidogrel/prasugrel/ticagrelor

Answer 29

see notes

Question 30

using a diagram describe the MoA of abciximab/tirofibal/eptifivatide

Answer 30

see notes

Question 31

using a diagram describe the MoA of warfarin

Answer 31

Warfarin decreases blood clotting by blocking an enzyme called vitamin K epoxide reductase that reactivates vitamin K1.[5]Without sufficient active vitamin K1, clotting factors II, VII, IX, and X have decreased clotting ability.

Question 32

using a diagram describe the MoA of heparins

Answer 32

see notes

Question 33

using a diagram describe the MoA of rivaroxaban/edoxaban/apixaban

Answer 33

see notes

Question 34

when are the DOACS commonly used?

Answer 34

prevention of stroke, systemic emboli in AF

Question 35

using a diagram describe the MoA of dabigatran/bivalirudin/argatroan

Answer 35

see notes