Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Haematology > Bleeding and Thrombosis > Flashcards

Bleeding and Thrombosis Flashcards

1
Q

What factors help to forma clot?

A

Platelets
Von Willebrand Factor
Coagulation Factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What causes the clot to remain within the confines of the injury?

A

Natural anticoagulants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What causes the clot to disappear?

A

Fibrinolytic System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What features of the endothelium also aid flow?

A

Non-stick surface cells

Produces nitric oxide, heparins, TFPI, Thrombomodulin and prostaglandins which also stop stuff sticking to it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What causes clotting factors to become activated?

A

Abnormal surface

Physiological activator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the first step of Clot formation?

A

Platelets recognise the abnormal surface and bind to it via receptors.
VWF and tissue factor are also produced to add platelet adhesion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which parts of the platelet bind to endothelium and which to the clotting factors?

A

Glycoproteins on surface bind to substances to you want to stick to the platelets.
Receptors on their surface bind to molecules that are released due to damage. This triggers signalling so substances can find site to clot.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the substances that can cause granules within the platelet to be released onto the surface of the platelet?

A

Alpha granules:
VWF
Thrombin

Dense granule:
ADP/ATP
Calcium
Serotonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the function of platelets in haemostats?

A

Adhere
Activation
Aggregation

Provide phospholipid surface for coagulation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does collagen bind to on a platelet?

A

GP1a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does vWF bind to on a platelet?

A

GP1b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the function of Thromboxane?

A

Allows platelets to shrink down and clump together (aggregate).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is required for the activation of coagulation factors?

A

Need scramblase to flip phospholipid membrane to surface of platelet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What binding sites are contained within a molecule of vWF?

A

Collagen
Platelets
Factor 8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What attaches to the initial platelet plug?

A

Fibrinogen bind to 2b3a receptor on platelet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What causes fibrinogen to become fibrin?

A

Activation of coagulation factors. When it becomes fibrin it is a solid clot.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the mechanism of the coagulation pathway.

A

Zymogens are activated by serum activates.
Factor 12, Factor 11, Factor 9, Factor 8, factor 10, Prothrombin and then Fibrinogen all need to be activated appropriately, in that order for coagulation to occur.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the cause of Haemophilia B?

A

Factor IX deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the cause of Haemophilia A?

A

Factor VIII deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the extrinsic pathway?

A

Factor 7 and tissue factor bind together to activate Factor 10.
Factor 10 then activates prothrombin to change int o thrombin.
Thrombin then activates fibrinogen to change into fibrin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the Intrinsic pathway?

A

Thrombin from extrinsic activates intrinsic.

Factor 11 activates Factor 9, Factor 9 and 8 then activate factor 10 to increase thrombin production.

22
Q

What are some examples of natural anticoagulants?

A

Tissue factor pathway inhibitor (TFPI)
Antithrombin
Activated Protein C and Protein S.

23
Q

What is the mechanism of action of TFPI?

A

Binds to activated factor 10 and 7 and deactivates them.

24
Q

What is the mechanism of action of Activated protein C and protein S?

A

Co-factor that binds to Factor 8 and factor 5 and switches them off.

25
Q

What is the mechanism of action of Antithrombin?

A

serum protease inhibitor that switches off thrombin, factor 10, factor 11, factor 9 and factor 8.

26
Q

What are activators of plasminogen and where are they released from?

A

t-PA and u-PA are activators of plasminogen that are released by the endothelium.

27
Q

What is the function of t-PA?

A

Cleaves plasminogen into molecules of plasmin. Plasmin then starts to attack the clot and breaks it into fragments. D-dimer is one of these fragments.

28
Q

What are some inhibitors of plasmin?

A

PA1-1
PA1-2
alpha-2-antiplasmin
alpha-2-macroglobulin

29
Q

What drugs acts on the P2y12 pathway?

A

(ADP pathway)
Clopidogrel
Prasugrel
Ticagrelor

30
Q

What drugs work on the GP2b/3a pathway?

A

Abciximab
Tirofiban
Eptifibatide

31
Q

What drug works on the COX pathway to produce thromboxane?

A

Aspirin

32
Q

What coagulation factors does warfarin work on?

A

Factors 2, 7, 9, 10.

Post translational modification to prevent them being activated.

33
Q

What coagulation factors does Heparins work on?

A

Bind to antithrombin to kill these proteases. Also factor 10

34
Q

What drugs are direct inhibitors of factor 10?

A

Rivaroxaban
Edoxaban
Apixaban

35
Q

What drugs are direct inhibitors of thrombin?

A

Dabigatran
Bivalirudin
Argatroban

36
Q

What is a thrombus?

A

Clot arising in the wrong place.

37
Q

What is a thromboembolism?

A

Movement of a clot along a vessel.

38
Q

What is Virchow’s triad of thrombosis?

A

Stasis
Hypercoagulability
Vessel damage

39
Q

What are some features of an arterial thrombus?

A

White clot - platelets and fibrin.
Results in ischaemia and infarction.
Principally secondary to atherosclerosis.

40
Q

What are some examples of arterial thromboembolism?

A

Coronary - MI, Unstable angina.
Cerebrovascular - stroke, transient ischaemia.
Peripheral - limb ischaemia.

41
Q

What are the risk factors for arterial thrombosis?

A 
Age
Smoking
Sedentary lifestyle
Hypertension
Diabetes mellitus
Obesity
Hypercholesterolaemia
42
Q

What is the management of arterial thrombosis?

A

Primary prevention - lifestyle modification, treat vascular risk factors.
Acute presentation - thrombolysis, anti platelet/anticoagulant drugs.
Secondary prevention.

43
Q

What are the features of venous thrombus?

A

Red thrombus - fibrin and red cells.
Results in back pressure.
Principally due to stasis and hyper coagulability.

44
Q

What are some examples of venous thromboembolism?

A 
Limb deep vein thrombosis
Pulmonary embolism
Visceral venous thrombosis
Intracranial venous thrombosis
Superficial thrombophlebitis.
45
Q

What are the risk factors for venous thrombosis?

A 
Stasis and hyper coagulability
Increasing age
Pregnancy
Surgery
Obesity
Systemic disease
Fam hx
Immobility
Tissue trauma
Hormonal therapy.
46
Q

What are some common systemic diseases that are associated with venous thrombosis?

A

Cancer
Myeloproliferative neoplasm (MPNs).
Autoimmune disease - IBD, Connective tissues disease e.g. SLE, Antiphospholipid syndrome (arterial and venous).

47
Q

How is venous thrombosis diagnosed?

A

Pretest probability scoring - wells score, geneva score.

Lab testing if probability low - D-dimer.
Imaging - doppler US, ventilation perfusion scan, CT angiogram.

48
Q

What drugs are used to treat venous thrombosis?

A

Anticoagulants - low molecular weight heparin, coumarins (warfarin), DOACs.
Thrombolysis in selected cases - massive PE.

49
Q

What is heritable thrombophilia?

A

Inherited predisposition to venous thrombosis.

50
Q

What are some causes of heritable thrombophilia?

A 
Factor 5 leiden
Prothrombin G20210A
Antithrombin deficiency 
Protein C deficiency
Protein S deficiency
51
Q

What are the features of microvascular thrombus?

A

Platelets and/or fibrin
Results in diffuse ischaemia
Principally in disseminated intravascular coagulation (DIC).

52
Q

What are some features of DIC?

A

Occurs in septicaemia, malignancy, eclampsia.
Causes tissue ischaemia - gangrene, organ failure.
Consumption of platelets and clotting factors leading to bleeding.

Haematology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions