07 Coagulation Cascade Flashcards Preview

02 Hematology And Immunology > 07 Coagulation Cascade > Flashcards

Flashcards in 07 Coagulation Cascade Deck (57):
1

Hemostasis involves three elements

Vascular wall or endothelium
Platelets
Coagulation cascade

2

Forms hemostatic plug at the site of vascular injury

Platelets

3

The function of platelets depends on:

Glycoprotein receptors
Contractile skeleton
Cytoplasmic granules

4

Action of platelets

Adhesion
Activation
Aggregation

5

Successive series of amplifying enzymatic reactions

Coagulation cascade

6

Need to be cleaved in order to be activated

Factors

7

Inhibits coagulation
Glycoproteins
Produced in liver
Third arm of the hemostatic system

Regulatory proteins

8

The rate-limiting factor in blood coagulation

Formation of prothrombin activator

9

Primary pathway of coagulation

Extrinsic pathway

10

The extrinsic pathway is initiated or triggered by

Interaction of circulating FVIIa with tissue factor

11

Coagulation factor that can catalyze its own reaction

FVII

12

Steps in the extrinsic pathway

Release of tissue factor
Formation of tissue factor complex

13

Intravascular, activation involves the interaction of blood with something within the bond

Intrinsic pathway

14

Steps in the intrinsic pathway

Activation of FXII
Activation of FXI
Activation of FIX
Activation of FX

15

Clotting factor catalysts

FV, FVIII

16

Vitamin K dependent clotting factors

FII, FVII, FVIX, FX

17

Vitamin Ki is a cofactors for the enzyme

Gamma-glutamylcarboxylase

18

Promotes carboxylation of one of the glutamic acid residues of the clotting factors to activate them

Vitamin K

19

Breaks down the fibrin and interferes with its polymerization

Plasmin

20

Synthesized in the liver and is circulated in plasma

Fibrinogen

21

Generated by proteolysis of plasminogen
Protease that breaks down fibrin

Plasmin

22

Inhibitor of Plasmin

Alpha 2-antiplasmin

23

Plasminogen activators

Tissue-type plasminogen activator (t-PA)
Urokinase-plasminogen activator (uPA)

24

Synthesized principally by endothelial cells and is most active when attached to fibrin

t-PA

25

Can activate plasmin in the fluid phase

uPA

26

The process in which clot formation is inhibited by limiting the activity of coagulant factors

Anti-coagulation

27

Cofactor to accelerate anti-coagulation

Heparin

28

Anti-thrombin inhibits:

Thrombin, FIXa, FXa, FXIa, FXIIa

29

Vitamin K-dependent zymogen
Bind to a specific receptor on the platelet surface and when activated will inactivate FVa and FVIIIa

Protein C

30

Vitamin-K dependent protein
When activated, it inhibits prothrombin activator

Protein S

31

Synthesized in endothelial cells
Present in plasma and platelets

Tissue factor pathway inhibitor

32

TFPI directly inhibits:

FXa, FVIIa, TFC

33

Hageman factor

FXII

34

Hemophilia by laboratory
No bleeding but blood takes longer to coagulate

FXII

35

Treatment FXI deficiency

Fresh frozen plasma replacement

36

FIX deficiency
Prolonged bleeding, easy bruising
Treated by replacement therapy

Hemophilia B

37

FVIII deficiency
Most common form of hemophilia

Hemophilia A

38

Bleeding from mucus membrane, bleeding into joints, muscles, excessive bleeding, epistaxis

Factor VII deficiency

39

Lack of fibrinogen causes blood not to clot

Afibrinogemia

40

Abnormal clot formation due to defective fibrin molecule

Dysfibrinogenemia

41

Formation of thrombus inside a blood vessel

Thrombosis

42

Virchow's triad (thrombus formation)

Endothelial injury
Stasis or turbulent blood flow
Hypercoagulability

43

Promotes platelet activation and adherence, release of tissue factor and depletion of prostacyclin

Endothelial injury

44

Tendency of blood to go in nonlinear, random directions

Stasis or turbulent blood flow

45

A detached intravascular solid, liquid, or gaseous mass that is carried by the blood to a site distant from its point of origin

Embolus

46

Reduction in platelet count leads to generalized bleeding
Normal PT, PTT

Thrombocytopenia

47

Four major categories of causes of thrombocytopenia

Decreased platelet production
Decreased platelet survival
Sequestration
Dilution

48

Provides information about type and number of blood cells in your body
Quantitative assessment of platelets

Complete blood count

49

Examines how fast small blood vessels on skin close to prevent bleeding
Assess platelet function

Bleeding time

50

Prolonged bleeding time

Impaired platelet function
Platelets below 80-100,000
Impaired vascular integrity

51

Assesses flow through membrane

Platelet function analyzer 100

52

Assesses/measures the integrity of the intrinsic system and its related factors
Utilizes a phospholipid reagent, a particulate activator and calcium chloride to start the enzyme reaction that leads to the formation of thrombin via intrinsic pathway

PTT assay

53

Assesses the integrity of the extrinsic system
Utilizes tissue thromboplastin and calcium chloride to initiate the formation of thrombin via the extrinsic pathway

PT assay

54

Measures fibrin formation
Useful to diagnose dysfibrinogenemias

Thrombin time

55

Prolonged thrombin time

Fibrinogen is reduced or abnormal
Presence of inhibitors
Presence of thrombin inhibiting drugs

56

Measures both intrinsic and common pathway
Synonymous with PTT

Activated partial thromboplastin time (aPTT)

57

Normal value (aPTT)

25-35 seconds