14. Aneurysms & Aortic Dissection Oedema & Shock

Question 1

Define the term aneurysm

Answer 1

Localised, permanent abnormal dilatation of blood vessel

Question 2

Clinicopahtological characteristics of abdominal aortic aneurysm

Answer 2

Most common
Erosion and replacement of the media by an adjacent complicated atheroma
Thrombus formation may lead to emboli

Question 3

Where would you find saccular aneurysms?

Answer 3

Brain

Question 4

Where are leutic aneurysms found?

Answer 4

Ascending aorta or arch of aorta

Question 5

What is a false aneurysm?

Answer 5

A blood filled space that forms round a blood vessel usually after injury/rupture.

Question 6

What are the classical triad symptoms for abdominal aortic aneurysm?

Answer 6

Pain in the neck
Hypotension
Pulsatile abdominal mass

Question 7

What happens in a dissecting aortic aneurysm?

Answer 7

Blood is forced through a tear in intima
Haemotoma in the media -propagated along blood vessel
Sharp tearing pain

Question 8

What are the possible outcomes dissecting aortic aneurysm?

Answer 8

Blood ruptures through adventita- massive haemorrhage into the pericardium and other structures
Blood will re-enter the aortic lumen - Double barrelled aorta
Blood may extend down tributary arteries- compress lumen- results in end-organ infarction

Question 9

Describe the parthenogenesis of AAA?

Answer 9

Degeneration of the media of the vessel
Cystic medial necrosis
Mucois degeneration, elastic fibre fragmentation

Question 10

What are the risk factors assocaited with AAA?

Answer 10

Hypertension
Bicuspid aortic valve
marfan syndrome

Question 11

What is marfan syndrome?

Answer 11

Point mutations in fibrillin gene prevent normal deposition of elastin in extracellular matirx

Question 12

Characteristics of Berry Aneurysms?

Answer 12

occur in circle of willis
NOrmal muscular arterial wall replaced by fibrous tissue
Arise at points of branching
More common in young, hypertensive patients

Question 13

What does the rupture of a berry aneurysm produce?

Answer 13

Saubarachnoid haemorrahage

Question 14

What are the symptoms of Saubarachnoid haemorrahage?

Answer 14

Thunderclap headache
Stiff neck
Nausea and vomiting 
Loss of consciousness 
Stroke like symptoms

Question 15

Characteristics of Charcot-bouchard aneurysms

Answer 15

Micro-aneurysms
Occur in intercerebral capillaries 
Rupture leads to intracerebral haemorrhage 
Associated with both 
-hypertension
-diabetic vascular disease

Question 16

Define oedema?

Answer 16

Excess fluid in the intersitial tissues

Question 17

Define effusion

Answer 17

A collection of fluid in a potential space

Question 18

What are the 4 categories of pathogenesis of oedema?

Answer 18

1. Inflammatory
2. Venous
3. Lymphatic
4. Hypoalbuminaemic

Question 19

Describe the inflammatory pathogenesis of oedema

Answer 19

Increased vascular permeability

Question 20

Describe the venous pathogenesis of oedema

Answer 20

Increased intravenous pressure

Question 21

Describe the lymphatic pathogenesis of oedema

Answer 21

Obstruction of lymphatic drainage

Question 22

Describe the hypoalbuminaemic pathogenesis of oedema

Answer 22

Reduced plasma osmotic pressure

Question 23

What us pitting oedema?

Answer 23

redistribution of the excess fluid when pressure is applied leaving pits

Question 24

What is a pulmonary oedema?

Answer 24

Abnormal accumulation of fluid in the intra-alveolar spaces of the lungs

Question 25

What are the causes of pulmonary oedema?

Answer 25

Left ventricular failure Renal failure Acute respiratory distress syndrome Pulmonary inflammation or infection

Question 26

What is a cerebral oedema?

Answer 26

Abnormal accumulation of fluid in brain parenchyma One part of brain herniates from one anatomical part to another

Question 27

Define shock

Answer 27

A pathological process that results in inadequate blood flow to sustain normal organ function

Question 28

What are the causes of shock?

Answer 28

Cardiogenic shock- MI Hypovolaemic shock-Haemorrhage -Increased vascular permeability/dilatation

Question 29

What are the phases of shock?

Answer 29

Compensatory phase Progressive phase Irreversible phase Failure of multiple organs

Question 30

What are compensatory mechanisms for shock?

Answer 30

Constriction of vessels in "non-vital" tissues to increase peripheral resistance Increased heart rate Dilation of cerebral vessels

Question 31

What signs will the clinical examination show for shock?

Answer 31

Cold Clammy Has an increased in heart rate

Question 32

What are the consequences of shock?

Answer 32

Renal failure Acute respiratory distress syndrome Cerebral infarction Infarction

Question 33

What is acute tubular necrosis?

Answer 33

Kidney injury characterised by acute tubular cell injury and dysfunction Leading to possible renal failure

Question 34

What are the features of acute respiratory distress syndrome?

Answer 34

A severe lung condition Severe inflammation of alveolar walls Accumulation of inflammatory cells and inflammatory proteinaceous material Severely impaired oxygen transfusion High mortality Type II pneumocytes that line the alveoli die