Lecture 6 Thrombosis, embolism and shock Flashcards Preview

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Flashcards in Lecture 6 Thrombosis, embolism and shock Deck (39):
1

Define thrombosis?

Formation of a solid or semi-solid mass from blood constituents which moves within vascular system.

2

Where may thrombi form?

1) lumen of heart 2) arteries 3) veins 4) capillaries.

3

What may aortic thrombus cause?

Ischaemia and emolism to the leg

4

What may vein thrombus cause?

Oedematous right leg. Deep vein thrombosis. ?after abdo surgery.

5

What do capillary thrombi cause?

(involves both thrombus formation and haemorrhage). Minute thrombi may cause scattered ischaemic lesions.

6

Factors that promote thrombosis

Virchow's triad. Abnormalities of 1) vessel wall 2) Blood flow 3) blood constituents

7

Factors affecting vessel wall in arteries?

Atheroma, inflammation

8

Factors affecting vessel wall in heart?

Myocardial infarction, rheumatic endocarditis.

9

Factors affecting vessel wall in veins?

1) Trauma, inflammation. 2) Chemicals (sclerosants - irritant substances injected to remove varicose veins). 3) Glucose (atheroma in diabetes)

10

Factors affecting vessel wall in capillaries?

Inflammation

11

General factors affecting blood flow?

Heart failure or circulatory shock.

12

Factors affecting blood constituents?

Polycythaemia, hyperproteinaemia, abnormalities of clotting

13

What is polycythaemia

abnormally ^ haemoglobin

14

What can make someone have polycythaemia?

Dehydration, polycythaemia rubra vera or chronic hypoxia.

15

What can lead to hyperptoteinaemia?

Multiple myeloma (tumour of plasma cells in bone marrow with accumulation of immunoglobins in plasma)

16

What can cause abnormalities of clotting?

Pregnancy (Xbleeding when placenta detaches). Older contraceptive pills, following trauma (liver produces more clotting factors). Thrombocythaemia.

17

Define thrombocythaemia

High platelet count in blood

18

What are the three thrombi fates?

Resolution (fibrinolysis), Organisation (incorporated into scar by macrophages/fibroblasts), Detachment (thromboembolism)

19

Define embolism

The transport of abnormal material (solid,liquid or gas) by the blood stream and its impacting in a blood vessel.

20

Types of emboli

Thrombi, fat (from multiple bone #), gas (infusion/vascular surgery).

21

What is caisson disease?

When ascending from the depths too rapidly, bubbles of N2 form in blood -> enters bones and joints -> pain known as bends.

22

How can an air embolus from IV therapy be found?

filled pericardium with water, cut into ventricular cavity, can see bubbles.

23

Types of emboli? (5)

Tumour material, infective agents, aheroma, amnootic fluid, foreign bodies.

24

Define shock

A physiological state. Systemic ↓ in tissue perfusion, ↓ oxygen delivery and insufficient removal of metabolic waste -> tissue injury

25

What causes hypovolaemic shock

Haemorrhage - internal or external. Severe burns.

26

What causes cardiogenic shock

Large acute myocardial infarction, other acute cardiac disease.

27

What causes neurogenic shock

Spinal cord trauma, regional anaesthesia.

28

What causes obstructive shock

Cardiac tamponade, tension pneumothorax, massive pulmonary embolism

29

Define cardiac tamponade

30

Define tension pneumothorax

build-up of air in pleural space. Due to lung laceration -> allows air into the pleural space.

31

What causes septic shock

Endotoxins (gram negative), exotoxins (gram positive). Both -> blood vessels dilating

32

What causes anaphylactic shock?

Severe form of allergic reaction

33

Clinical features of shock: BP?

↓BP

34

Clinical features of shock: HR?

Tachy >90bpm

35

Clinical features of shock: RR?

29 breaths per minute

36

Clinical features of shock: Urine output?

Low

37

Clinical features of shock: blood vessels?

Cutaneous vasoconstriction/vasodilation

38

Clinical features of shock: feelings?

anxiety, agitation OR indifference, lethargy, obtunded.

39

Clinical features of shock: Additional?

Hypoxia, metabolic acidosis.