Acute Stroke and TIA Flashcards Preview

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Flashcards in Acute Stroke and TIA Deck (45)
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1
Q

If someone presented with clinical features suggestive of a stroke, what would you do?

A
  • ABCDE
  • History - Exact onset, changes/progression, Risk factors
  • Examination - full neuro exam, CVS, systemic and risk factor exam
2
Q

When would you treat hypertension in someone presenting with a stroke?

A
  • Hypertensive emergency (encephalopathy/aortic dissection)
  • If thrombolysis is being considered
3
Q

How long after presentation with symptos of a stroke should someone get a CT head?

A

Within 1 hour

4
Q

When is CT/MRI within the first hour of presentation with stroke sypmtoms essential?

A
  • If thrombolysis considered
  • High risk of haemorrhage
  • Unusual presentation - fluctuating consciousness
5
Q

What is the most sensitive imaging modality for detecting acute infarction?

A

Diffusion-weighted MRI

6
Q

What happens at a cellular level when cerebral infarction occurs?

A

Hypoxic damage:

  • Na+/K+ pump Fails -> Na+ accumulates in the cell -> osmotic shift into cell -> cellular swelling
    • Cells in the immediate area around the infarct die very quickly, as they swell and burst. Cells in “penumbra” are relatively less oematous, and can be “saved”
  • Excitotoxicity - Damage as a result of prolonged depolarisation of cells in affected area
    • Results in failure of AMPA and NMDA receptors - allows excessive calcium into the cell. This causes release of free radicals, production of cytokines, and direct apoptotic effects in the penumbra
9
Q

What specific things might you look for on examination in someone presenting with features of a stroke?

A

Assess extent and localise

  • Thorough, full neruo exam - clinical diagnosis and lesion localisation

Look for risk factors

  • Pulse (AF)
  • Heart sounds (valve disorders)
  • Carotid Bruit
  • Signs of PVD
  • Bruising/Bleeding
  • Xanthalasma/Xanthoma/Corneal arcus
  • Tar Staining
10
Q

When would you consider thromblysis in someone presented with a stroke?

A

Once haemorrhage has been excluded as cause, and within 4.5 hour window of onset (benefits outweigh risks within this window)

11
Q

Within what time frame are the best results achieved using thrombolysis?

A

Within 90 minutes of onset

12
Q

What thrombolytic agent is most commonly used in stroke management?

A

Alteplase

13
Q

What are contraindications to thrombolysis in a stroke?

A

Look them up - Impossible to remember all of them!!! - think of categories of contraindications

  • Stroke related
  • Neurological
  • Bleeding tendency
  • Trauma
  • Medical problems
14
Q

What are stroke related contraindications to thrombolysis

A
  • Rapidy improving symptoms
  • Ischaemia of >1/3 MCA territory
  • Symptoms suggestive of SAH
  • Seizure at start of stroke
15
Q

What are neurological contraindications to thrombolysis?

A

History of intracrnal bleed, aneurysm or neoplasma

Spinal or cranial surgery/injury

16
Q

What bleeding tendency risk factors are contraindicaitons to thrombolysis?

A
  • Significant bleeding disorder
  • Therapeutic anticoagulation - LMWH, DOACs, Warfarin
  • Iron deficiency anaemia
  • Thrombocytopenia
  • Advanced liver disease
17
Q

If thrombolysis was contraindicated, what treatment would you start someone on for acute treatment of a stroke?

A

Aspirin PO/PR OD for 2 weeks or

Clopidogrel 300mg PO STAT, then 75 mg OD

18
Q

What are trauma related contraindications to thrombolysis in stroke?

A
  • Significant head injury <3 months
  • Major surgery/delivery/external heart massage <2 weeks
  • Puncture of non-compressible blood vessel <2 weeks
19
Q

What medical problems are contraindications for thrombolysis in stroke?

A
  • SBP > 180/DBP >110
  • Active internal bleeding
  • Aortic aneurysm
  • Bacterial endocarditis/pericarditis
  • Acute pancreatitis
  • Haemorrhagic retinopathy
  • Oesophageal varices
  • Ulceratie GI disease <3 months
  • GI/GU haemorrhage < 3 weeks
21
Q

Why does diffusion weighted MRI detect early abnormalities seen in infarction better than normal MRI or CT?

A

This type of MRI exploits the fact that damaged cells fill with water – and thus contain more water than normal cells in the early stages of damage.

22
Q

What intial investigations would you consider doing in someone presenting with a stroke?

A
  • CT/MRI - within 1 hour
  • MRI angiography
  • ECG
  • CXR
  • Bloods - ESR, FBC, clotting screen, glucose, Lipids/cholesterol
23
Q

Why might you do an ESR on someone presenting with features of a stroke?

A

If with headache and tender scalp - Giant cell arteritis

24
Q

Why might you do FBC or clotting in someone presenting with a stroke?

A

Look for evidence of clotting/bleeding disorders - thrombocytopenia, polycythaemia

25
Q

What would you want to prioritise in your ABCDE assessment in someone presenting with a stroke?

A
  • Maintain airway
  • Prevent hypoxia
  • Hydrate
  • Treat fever / source of fever – this can help to limit the extent of damage
  • Treat hypo / hyperglycaemia
26
Q

What dose of aspirin would you give someone if thrombolysis was contraindicated?

A

300 mg

27
Q

How long would you put someone on aspirin treatment for following a stroke?

A

2 weeks

28
Q

If someone presented with a TIA with amaurosis fugax, where might the occlusion be taking place?

A

Retinal artery occlusion

29
Q

What dose of clopidogrel would you give someone as long-term prophylaxis?

A

75 mg OD

30
Q

What could you give someone if they did not tolerate clopidogrel for post-stroke prophylaxis?

A

Slow-release dipyridamole

31
Q

What is the definition of a transient ischaemic attack?

A

A brief episode of neurological dysfunction due to temporary focal cerebral or retinal ischaemia without infarction, e.g. a weak limb, aphasia or loss of vision, usually lasting seconds or minutes with complete recovery. TIAs may herald a stroke. The arbitrary time of <24 hours is no longer used.

33
Q

What are causes of TIA?

A
  • Atherothromboembolism
  • Cardioembolism - Mural thrombus, AF, Valve disease
  • Hyperviscosity - polycythaemia, sickle-cell, myeloma
  • Vasculitis - cranial arteritis, SLE, PAN
34
Q

What are features of an anterior circulation TIA?

A

Carotid system

  • Amaurosis fugax
  • Aphasia
  • Hemiparesis
  • Hemisensory loss
  • Hemianopic visual loss
35
Q

What are features of a posterior circulation TIA?

A
  • Diplopia, vertigo, vomiting
  • Choking and dysarthria
  • Ataxia
  • Hemisensory loss
  • Hemianopic visual loss
  • Bilateral visual loss
  • Tetraparesis
  • Loss of consciousness (rare)
  • Transient global amnesia (possibly)
36
Q

If, on examination of someone presenting with signs of a TIA, you found there to be central retinal artery occlusion, where might this suggest there is stenosis in the carotid system?

A

Internal carotid artery stenosis

37
Q

What scoring system could you use to stratify those who have had a TIA who might be at higher risk of stroke in the future?

A

ABCD2 score - score >/=4 indicates high risk of early stroke - assess by specialist in 24 hours

38
Q

What differentials would you want to consider in someone presenting with features of a TIA?

A
  • Hypoglycaemia
  • Migraine aura
  • Focal epilepsy
  • Hyperventilation
  • REtinal bleeds
  • Malignant hypertension
  • MS
  • Intracrnaial tumours
  • Peripheral neuropathy
  • Phaeochromocytoma
  • Somatization
39
Q

What investigations would you consider doing in someone with a suspected TIA?

A
  • Bloods - FBC, U+E’s, Glucose, Lipids
  • CXR
  • ECG
  • Carotid doppler +/- angio
  • CT/Diffusion weight MRI
  • ECHO
40
Q

How would you manage someone with a TIA?

A
  • Control risk factors - BP, DM, Hyperlipidaemia, Smoking
  • Antiplatelet therapy - Aspirin (300mg) for 2 weeks, then clopidogrel (75mg) long-term
  • Consider anticoagulation - AF
  • Consider carotid endartectomy - within 2 weeks of presentation if >70% stenosis and no contrindiations
41
Q

How long after a TIA are individuals not allowed to drive?

A

1 month - Need to inform DVLA if stll symptomatic after 4 weeks or HGV driver

42
Q

What risk factors would you ask about in the history of someone with a suspected stroke?

A
  • Smoking
  • HTN
  • Diabetes
  • AF
  • CVS disease
43
Q

How soon after TIA symptoms present would you want to get specialist review?

A

24 hours

44
Q

What procedure would you consider doing following a TIA?

A

Carotid endarterectomy

45
Q

What type of strokes is acute severe hypertension treated in?

A

Haemorrhagic, not ischaemic!!!

46
Q

In the long terms, what investigations might you consider doing in someone who has had a TIA?

A
  • ECG
  • 24-hour tape
  • ECHO +/- bubble study - patent foramen ovale
  • Vasculitis screen
  • Thrombophilia Screen
47
Q

How long after a stroke would you start statin therapy?

A

48 hours

48
Q

What medications would you start someone on as long term therapy following stroke/TIA?

A
  • Antihypertensives
  • Clopidogrel 75 mg OD - after 2 week therapy
  • Statin
49
Q

What specific medication would you consider putting someone on if their stroke was caused by AF?

A

Warfarin/DOAC