Brainscape's Knowledge GenomeTM

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


See full index

Pathological Processes * > S5 Thrombosis and Embolism > Flashcards

S5 Thrombosis and Embolism Flashcards

1
Q

What is thrombosis?

A

Formation of a solid mass of blood within the circulatory system. The solid mass is called a thrombus.

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

What is a clot?

A

A mass of blood outside the vessel wall

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

What is Virchow’s triad?

A
  1. Vessel wall (damage)
  2. Blood flow (stasis)
  3. Blood components (hypercoagulable)

Explains how a thrombus forms

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

What are some examples of vessel wall/endothelial wall damage?

A
  • atheroma
  • direct injury
  • inflammation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some problems with blood flow?

A
  • stasis - slow blood flow (e.g. chronic hypotension)

* turbulent blood flow (e.g. valves or atheroma)

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

Is thrombosis more common in veins or arteries?

A

Veins as blood flow is slower and veins also have valves that can cause turbulent flow

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

What are some problems with blood components?

A
  • hypercoagulable states (increased levels of fibrinogen and factor VIII)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which groups of people usually have hypercoagulable blood?

A
  • smokers
  • pregnant women or post-partum women
  • post-operative patients
  • cancer patients
  • trauma and burns patients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does an arterial thrombus look like?

A
  • pale
  • granular
  • lines of Zahn
  • lower cell content
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why do lines of Zahn form?

A

In high flow areas, RBCs, platelets and fibrin become layered

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

What does a venous thrombus look like?

A
  • soft
  • gelatinous
  • deep red
  • higher cell content
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does a thrombus get broken down?

A

By fibrinolysis

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

When does lysis of a thrombus occur? What does it result in?

A
  • when thrombi are small
  • fibrinolytic system is activated
  • complete dissolution of thrombus
  • blood flow is re-established
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is propagation of thrombi?

A

The progressive spread of thrombosis

Spread distally in arteries and proximally in veins - in respect to heart

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

What is organisation of thrombi?

A
  • a repair process
  • leads to growth of fibroblasts and capillaries (like granulation tissue)
  • the lumen remains obstructed
  • this is not ideal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is recanalisation?

A

Blood flow is re-established but not completely

One or more channels are formed through an organising thrombus

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

What is an thromboembolism?

A

When part of a thrombus breaks off, travels through the bloodstream and lodges at a distant site

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

What are the effects of thrombosis on the tissue if it is a venous thrombi?

A
  • oedema
  • ischaemia
  • infarction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a common thrombi?

A

DVT - deep vein thrombosis

20
Q

Where can thrombi form in veins (other than DVT)?

A
  • sinus thrombosis (in brain)
  • thrombosis in subclavian vein
  • thrombosis in hepatic vein
  • uteroplacental thrombosis in pregnancy (can lead to miscarriage)
21
Q

What are the effects of thrombosis on the tissue if it is a arterial thrombi?

A
  • ischaemia

* infarction

22
Q

Where can thrombi form in arterial system?

A
  • cerebral artery - leads to ischaemic stroke
  • carotid artery - ischaemic stroke
  • coronary artery - MI
  • mesenteric artery - bowel ischameia
  • renal artery
  • femoral/iliac/popliteal arteries - acute ischaemic limb
23
Q

What is an embolism?

A

An embolism is the blockage of a blood vessel by a solid, liquid or gas at a site distant from it’s origin

Most common is thromboemboli

24
Q

What is a pulmonary thromboemboli?

A

When an emboli passes from the systemic veins to the lungs

25
Q

Where would a thrombus in the heart pass to via the arteries?

A

Passes via the aorta and lodges in the renal, mesenteric, etc arteries

Results in bowel ischaemia, renal infarction, etc

26
Q

Where would an emboli go from an atheromatous carotid artery to?

A

To the brain leading to ischaemia stroke

27
Q

Where would an emboli go from an atheromatous abdominal aorta to?

A

To arteries of the legs leading to acute limb ischaemia

28
Q

What are some predisposing factors for a DVT?

A
  • immobility/bed rest
  • post-operative
  • pregnancy/post-partum
  • oral contraceptives
  • severe burns
  • cardiac failure
  • disseminated cancer
29
Q

Pulmonary thromboembolism of different sizes/locations have different effects. What would be the effect of a massive coiled embolus in the main pulmonary artery? Of a small embolus lodged in a peripheral pulmonary artery? And multiple repeated small emboli?

A
  • sudden death
  • pulmonary infarct
  • pulmonary hypertension
30
Q

What does a massive pulmonary embolism cause?

A

60% reduction of blood flow - rapidly fatal

Especially if a saddle emboli

31
Q

What is a saddle emboli?

A

An embolus that sits either side of the of the pulmonary arteries (at the bifurcation)

32
Q

What does a major pulmonary embolism result in?

A

Blocks medium sized vessels

Patient will have shortness of breath with/without a cough and blood stained sputum

33
Q

What does a minor pulmonary embolism result in?

A

Small peripheral pulmonary arteries are blocked

This is asymptomatic or patient may have minor shortness of breath

34
Q

What do recurrent minor pulmonary embolisms lead to?

A

Lead to pulmonary hypertension

35
Q

What does a thromboembolism to the foot result in?

A

Ischaemia - gangrene

36
Q

What does a thromboembolism from the carotid artery result in?

A

Ischaemic stroke

37
Q

What are other types of embolism?

A
  • air
  • amniotic fluid
  • nitrogen
  • medical equipment (e.g. silicon or drugs (talcum emboli))
  • tumour cells
  • fat, bone marrow (post trauma)
38
Q

What is an iatrogenic emboli?

A

A emboli caused by medical treatment/examination

39
Q

What are the prophylaxis of DVT/PE?

A
  • identify high risk patients
  • give low molecular weight heparin subcutaneously (advantage as it is fast acting)
  • mobilise early
  • leg compressions during surgery e.g. stockings/flowtron boots
40
Q

How can thrombus (and/or thromboemboli) be treated?

A
  • clot busters - streptokinase, alteplase (recombinant tPA)
  • IV heparin type drugs
  • Novak oral anticoagulants (rivaroxaban, apixaban, edoxaban - antifactor Xa and dabigatran)
  • filters in inferior vena cava/devices in left atria to stop thrombus formation
  • embolectomy
  • oral warfarin
41
Q

What does dabigatran inhibit?

A

Inhibits thrombin

42
Q

What does heparin inhibit?

A

Inhibits factor V

43
Q

What does warfarin inhibit?

A

Factors II, VII, IX, X and protein C and S

44
Q

What do natural anticoagulants inhibit?

A

Thrombin formation

45
Q

What is a paradoxical emboli?

A

Very rare

Thromboemboli that form in systemic veins but embolism in systemic arteries (small emboli pass through arterio-venous anastomoses in pulmonary circulation or larger emboli enter systemic circulation by passing through defects in interventricular septum/patent foramen ovale during coughing, lifting or straining (increase pressure in right side of heart))

46
Q

How can aspirin be used to treat thromboembolic disease?

A

It is antithrombogenic

Irreversibly acetylates cyclooxygenase - means platelets can’t produce thromboxane A2 (platelet aggregator)

Pathological Processes * (10 decks)

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