2 - Haemodynamic disorders Flashcards Preview

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Flashcards in 2 - Haemodynamic disorders Deck (29)
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1
Q

What causes pulmonary oedema?

What causes this?

A

raised hydrostatic pressure in the pulmonary capillary bed

this is caused by left ventricular failure
(increased pressure in the left atrium—> back pressure-volume in the capillaries—> pushes fluid into the interstitial space

2
Q

What is cardiogenic pulmonary oedema?

A

fluid accumulated in the interstitial space and spills over into the alveolar walls

3
Q

What is non-cardiogenic pulmonary oedema caused by?

A

increased permeability

4
Q

What is ARDS?

What are the most common causes?

What is the main symptom?

A

acute respiratory distress syndrome

causes: sepsis, shock, trauma

main symtom is dyspnea

5
Q

List the 4 types of cerebral oedema

A
  • vasogenic
  • cytotoxic
  • osmotic
  • interstitial
6
Q

What is a vasogenic cerebral oedema?

What are the causes?

A

physical breakdown of the blood-brain barrier

causes: trauma and tumours

7
Q

What is a cytotoxic cerebral oedema?

A

derangement of the sodium-potassium pump leads t o a build of intracellular sodium, causing intracellular oedema

common in ischaemic strokes

8
Q

What is an osmotic cerebral oedema?

What is the cause?

A

reduction in plasma osmolality

cause: SIADH (syndrome of inappropriate ADH secretion), which is commonly caused by small cell carcinoma

9
Q

What is an interstitial cerebral oedema?

What is the cause?

A

breakdown of the CSF-brain barrier

cause: obstructive hydrocephalus
CSF moves into the interstitial space

10
Q

What is anasarca?

A

sever generalised oedema

11
Q

Define generalised oedema?

A

the widespread accumulation of fluid in subcutaneous tissue and serous cavities

12
Q

Define thrombosis

A

an abnormal blood clot formation in the circulatory system

13
Q

What often causes vessel war injury?

A

atherosclerotic plaques

14
Q

What is a stenosis?

What does it cause?

A

narrowing of an artery by the thrombus

causes ischaemia

15
Q

What is an occlusion?

What does it cause?

A

complete blockage of an artery by a thrombus

causes infarction of the tissue supplied by the artery

16
Q

Define embolism

A

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

most are thromboemboli (fragments of dislodged thrombus)

17
Q

What are the other types of embolic material?

A
  • fat
  • air
  • amniotic fluid
  • tumour
18
Q

Where do venous thromboemboli originate from and what is the major consequence?

A

most originate from the deep veins (DVT)

major consequence is pulmonary (thrombosis)embolism

19
Q

Why is there a range of consequences of pulmonary thromboemboli?

A

consequence depends on the size and where it becomes lodged

e.g. emboli lodging in a major pulmonary artery will cause instantaneous death

20
Q

What is a saddle embolus?

A

one that becomes lodged at the bifurcation of the pulmonary trunk

21
Q

What are the symptoms when a pulmonary embolism lodges in a middle sized artery?

A

breathlessness

22
Q

Where do arterial thromboemboli originate from and what can it cause?

A

originate from carotid arteries

most likely to affect cerebral arteries and cause stroke

23
Q

Where do cardia thromboemboli originate from?

Where can it lodge and what are the consequences?

A

originate from the left side of the heart
can lodge in:
- cerebral artery= stroke
- mesenteric artery= bowel infarction
- lower limb artery= acute lower limb infarction

24
Q

Define haemorrhage

A

extravasation of blood due to vessel rupture

can be external or enclosed within a tissue

25
Q

What are the causes of haemorrhage?

A

trauma

intrinsic disease of the vessel

26
Q

How are haemorrhages classified?

A

based on their size

27
Q

What can be the result or a solid haematoma within the cranial cavity?

A

can be fatal

causes a rise in ICP and (tonsillar) herniation

28
Q

When does shock occur?

A

when tissue perfusion is insufficient to meet the metabolic demand

29
Q

Give the equation for mean arterial pressure

A

MAP = CO x SVR

Mean arterial pressure = cardiac output x systemic vascular resistance (total peripheral resistance)