Stroke (3)

Question 1

Stroke

Answer 1

Sudden onset, focal neurological deficit of vascular origin, symptoms last over 24 hours/death

Question 2

Sir Godfrey Hounsfield

Answer 2

X-ray computed tomography

Question 3

What percentage of strokes are caused by infarction?

Answer 3

85%

Question 4

What percentage of strokes are caused by haemorrhage?

Answer 4

15%

Question 5

Acute ischaemic stroke

Answer 5

Initial reduction in cerebral blood flow > ischaemia > alterations in cellular chemistry > cellular necrosis

Question 6

Cerebral blood flow

Answer 6

50-55ml/100g

Question 7

Average brain weighs

Answer 7

1400g (2% body weight)

Question 8

Average Cerebral Blood Flow

Answer 8

800ml/min (15% cardiac output)

Question 9

Whole brain oxygen consumption (CMRO2)

Answer 9

3.3-3.5ml/100g/min
45ml O2/min
20% total body O2 consumption at rest

Question 10

Flow =

Answer 10

pressure/resistance

Question 11

CPP

Answer 11

Cerebral perfusion pressure

Question 12

CVR

Answer 12

Cerebrovascular resistance

Question 13

CBV

Answer 13

Cerebral blood volume

Question 14

OEF

Answer 14

Oxygen extraction fraction (30% normally)

Question 15

PaCO2

Answer 15

1mmHg rise > 3-5% increase in CBF

Question 16

Viscosity

Answer 16

Normally mainly haematocrit

Question 17

What is the sole substrate for energy metabolism in the cerebrum?

Answer 17

Glucose (75-100mg/min or 125g/day)

Question 18

Glucose is metabolised by the … sequence and the … cycle

Answer 18

glycolytic sequence and the tricarboxylic acid cycle

Question 19

Neurones require a constant supply of ATP, why?

Answer 19

To maintain integrity (K+ inside, Na+ and Ca2+ outside), cannot be stored

Question 20

Glycolysis

Answer 20

1M glucose > 2M pyruvate (generates 2M ATP in process)

Question 21

Aerobic

Answer 21

Pyruvate > CO2 and H20 + 36 ATP

Question 22

Anaerobic

Answer 22

Pyruvate > lactate + 2M ATP

Question 23

What causes ischaemic stroke?

Answer 23

Athero-thrombo-embolism
Thrombosis (extra-cranial/intra-cranial)

Embolism (cardiogenic/artery to artery)

Atrial Fibrillation

Question 24

Treatment

Answer 24

Thrombolysis, early recanalisation or stentrivers

Question 25

Which vessel occlusion accounts for 18-25% of all ischaemic stroke but 60-70% of deaths/severe disability?

Answer 25

Proximal anterior circualtion large vessel occlusion (ICA/M1)

Question 26

Stentrievers

Answer 26

Stents reperfuse brain, leave for 10 mins, withdraw stent with smaller clot 'core'