Stroke

Question 1

Pathophysiology of stokes

Answer 1

Ischaemic - 85%

• large arthersclerosis + thromboembolic
• Cardioembolic
• Lacunar (thrombus in situ)
• More likely if carotid bruit, AL, past TIA, IHD

Hameorrhagic 15%

• Hypertension
• berry aneurysm
• Coagulopathy eg. APLS
• AV malformation
• More like meningism, severe headache and coma within hours

Subarachnoid 5% - sudden severe headache
Other = Watershed infarct - after sudden drop in BP

Question 2

History and exam findings anterior circulation

Answer 2

Anterior circulation: 
Internal Carotid Artery 
- hemiparesis and hemianaesthesia on opposite side
- homonymous hemianopia 
- dysphasia 

Ant Cerebral artery

• Hemiparesis L>R
• Sensory loss legs only
• personality, mood, behaviour change

Middle cerebral artery

• Left MCA =R sided weakness involving lower face and arm > leg with dysphasia
• Right MCA = L sided weakness involving lower face and arm > leg with visual and/or sensory neglect

Question 3

History and exam findings Posterior circulation and vertebrobasilar

Answer 3

Posterior cerebral artery

• homonymous hemianopia
• parietal deficits= spacial skills, recognition
• temporal deficits = memory, mood, aggression

Vertebrobasilar arterial system
Midbrain
- 3rd and 4th cranial nerve deficit same side
- weakness and sensory loss opposite side
Pons
- 5th 6th CN palsy same side
- weakness and sensory loss opposite side
Medulla
- 9 10 11 Cn palsy same side
- weakness and sensory loss opposite side
Cerebellum
-DASHING
=dysdiadochokinesia (loss of RAM) and dysmetria (overshoot/under), ataxia, slurred speech, hypotonoa, intention tremor, nystagmus, gait abnormality

Question 4

Differential diagnosis?

Answer 4

• migranes with focal seizures
• seizures with poti-ictal paresis
• haemorrhage into SOL
• MS
• Drug overdose
• Head injury
• Hypoglycaemia

Question 5

Investigations

Answer 5

Bloods: FBC, UEC, BSL, Lipids, Coags
- thrombophilia screen if < 50
ECG: ?AF 
Imaging: 
- CT or MRI 
- Carotid USS 
- ECHO

Question 6

Management

Answer 6

Primary prevention:
control risk factors: HTN, DM, Lipids, low Exercise, diet, smoking

Acute Ischaemia: 
- airway
- BP - autoregulation lost 
- BSL 
- CT brain ASAP 
= Thrombolyse (within 4.5h) +/- thrombectomy <6h for AC and <24H if PC 
      exclusion: 
         - HTN 185/110
         - recent stroke
         -recent MI 
         -recent surgery/trauma (30 days) 
Clopidogrel + Aspirin 
DVT prophylaxis 
Driving restriction

Acute Haemorrhage:

• stop antithrombotics
• reverse anticoag
• neurosurg

Question 7

Secondary Prevention?

Answer 7

Clopidogrel 70mg daily
Control HTN
Statins 40mg regardless of lipids
Smoking cessation
Consider carotid endarterectomy if >70% stenosed
If in AF consider anticoag once stable (not too fast though to avoid haemorrhagic transformation)