Absite Hemostasis

Front 1

DRAW THE COAG CASCADE

Back 1

-

Front 2

Name 4 major events in hemostasis

Back 2

1.) Vascular constriction
2.) Platelet plug formation
3.) Fibrin formation
4.) Fibrinolysis

Front 3

Etiology of acute coagulopathy in trauma

Back 3

activation of protein C and fibrinolysis

Front 4

Where is thromboxane (TXA2) from?

Back 4

Platelets

Front 5

Where is prostacyclin from?

Back 5

Endothelium

Front 6

What is the action of PGI2

Back 6

decreases platelet aggregation and promotes vasodilation

Front 7

Name 3 actions of TXA2

Back 7

1.) increases platelet aggregation and promotes vasoconstriction
2.) triggers Ca release in plts to expose GpIIb/IIIa receptor --> plt-plt binding
3.) Activates PIP system to further increase calcium

Front 8

Name 2 potent vasoconstrictors

Back 8

endothelin
serotonin (5-hydroxytryptamine)

Front 9

How do endothelial cells prevent clotting?

Back 9

Interfere with platelet recruitment by inactivating ADP

Front 10

Action of heparin sulfate

Back 10

catalyzes inhibition of thrombin by antithrombin

Front 11

Action of thrombomodulin

Back 11

down-modulates coagulation process through activation of protein C

Front 12

Percentage of circulating platelets that may be sequestered in spleen

Back 12

30%

Front 13

Average life span of platelets

Back 13

7-10 days

Front 14

Describe primary hemostasis

Back 14

intimal injury exposes subendothelial collage which platelets adhere to via vWF

Hint 14

reversible

Front 15

Action of vWF

Back 15

binds to GPI/IX/V on platelet membrane

Front 16

Name 2 principal mediators in platelet aggregation

Back 16

ADP and serotonin

Front 17

2 ways that platelets contribute to hemostasis

Back 17

Forming hemostatic plug and contributing to thrombin formation

Front 18

Which receptor allows platelet-collagen binding?

Back 18

GpIb receptor

Front 19

What is TXA2 derived from?

Back 19

Arachidonic acid (from plts) -> prostaglandin G2 --> PGH2 --> TXA2

Front 20

Action of ASA

Back 20

Irreversibly inhibit platelet COX

Front 21

Action of NSAIDs

Back 21

Reversibly blocks platelet COX

Front 22

Describe second wave of platelet aggregation

Back 22

Release reaction of ADP, calcium, serotonin, TXA2, alpha-granule proteins

Front 23

What is a required cofactor in the second wave of platelet aggregation?

Back 23

Fibrinogen which acts as a bridge for GPIIb/IIIa receptor (plts form a plug that is no longer reversible)

Front 24

Site of secretion and action of thrombospondin

Back 24

alpha granules and stabilizes fibrinogen binding to activated platelets

Front 25

Action of platelet factor 4

Back 25

potent heparin antagonist

Front 26

4 Inhibitors of second wave of platelet aggregation

Back 26

ASA, NSAIDS, cAMP, NO

Front 27

Result of release reaction

Back 27

Alterations in phospholipids of platelet membrane that allow calcium and clotting factors to bind to platelet surface (aka platelet factor 3)

Front 28

Define prothrombin complex

Back 28

X, V, Ca, Platelet factor 3, and prothrombin which forms on platelets

Front 29

Action of prothrombin complex

Back 29

Catalyzes formation of thrombin

Front 30

Convergence point of intrinsic and extrinsic pathways

Back 30

Factor X

Front 31

What inhibits Factor X

Back 31

Tissue factor pathway inhibitor

Front 32

What is the key to coagulation?

Back 32

Thrombin!
1.) Converts fibrinogen to fibrin and FSP
2.) Activates factors V and VIII
3.) Activates platelets

Front 33

What helps crosslink fibrin?

Back 33

XIII

Front 34

Describe intrinsic pathway

Back 34

exposed collagen + prekallikrein + HMW kininogen + factor XII --> activates XI --> activates IX + VIII --> activate X + V --> convert prothrombin (factor II) to thrombin

Front 35

Extrinsic pathway

Back 35

Tissue factors from injured cells + factor VII --> activate X + V --> convert prothrombin to thrombin

Front 36

Which factor has the shortest half life

Back 36

Factor VII

Front 37

Which factors are labile without any activity in blood but retained in FFP?

Back 37

V and VIII

Front 38

Vitamin K dependent factors

Back 38

II, VII, IX, X, proteins C & S

Front 39

How long does Vit K take to work?

Back 39

6 hours

Front 40

How long does FFP take to work and how long does it last for?

Back 40

Immediate; 6 hours

Front 41

Half life of RBCs

Back 41

120 days

Front 42

Half life of PMNs

Back 42

1-2 days

Front 43

Key to anticoagulation

Back 43

AT III

Front 44

Actions of AT III

Back 44

Inhibits thrombin
Inhibitors factors IX, X, XI
Bound by heparin

Front 45

Actions of protein C

Back 45

Degrades factors V and VIII and fibrinogen

Front 46

Action of protein S

Back 46

Protein C cofactor

Front 47

Fibrinolysis involves?

Back 47

Tissue plasminogen activator, plasmin, Alpha-2 antiplasmin

Front 48

Where is tissue plasminogen activator released?

Back 48

endothelium

Front 49

Action of plasmin

Back 49

Degrades Factors V, VIII, fibrinogen, fibrin --> lose platelet plug

Front 50

Natural inhibitor of plasmin

Back 50

Alpha-2 antiplasmin (released from endothelium)

Front 51

What blood product contains the highest concentration of vWF VIII?

Back 51

Cryoprecipitate

Front 52

What does FFP comprise of?

Back 52

high levels of all factors, protein C & S, AT-III

Front 53

Action of ddAVP & conjugated estrogens

Back 53

Cause release of VIII and vWF from endothelium