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Flashcards in Blood supply and stroke Deck (35)
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1
Q

What do the internal carotid arteries supply?

A
  • Anterior 3/5 of cerebrum

* Diencephalon

2
Q

What are the main branches of the internal carotid arteries?

A
  • middle cerebral artery (MCA)
  • Anterior cerebral artery (ACA)
  • Perforating branches (striate, lenticulochoroidal arteries etc.)
3
Q

What do the vertebrobasilar arteries supply?

A
  • Brainstem
  • Cerebellum
  • Posterior 2/3 cerebrum
4
Q

What are the main branches of the vertebrobasilar arteries?

A
  • Cerebellar (PICA, AICA, SCA)
  • Pontine
  • Posterior cerebral arteries
  • Striate and thalamic branches
5
Q

What supplies the brainstem?

A
  • posterior circulation:
  • Posterior cerebral
  • SCA (superior cerebellar)
  • Basilar
  • AICA
  • PICA
6
Q

What are the main signs of stroke?

A
  • Sudden onset
  • Facial asymmetry
  • Speech disturbance (dysphasia)
  • Asymmetrical weakness in muscles
7
Q

What is a stroke?

A
  • Interruption of the blood supply to a focal part of the brain causing loss of neurological function
  • Symptoms last over 24 hours or lead to death with no apparent cause other than that of vascular origin
8
Q

What is a transient ischaemic attack?

A
  • Same cause as stroke

* Symptoms lasting less than 24 hours

9
Q

3 types of stroke

A
  • Haemorrhagic
  • Ischaemic
  • Subarachnoid haemorrhage
10
Q

What are the causes of haemorrhage stroke?

A
  • Hypertension
  • Tumour
  • Bleeding disorders
  • Vascular malformation
  • Amyloid pathology
11
Q

What are the causes of ischaemic stroke?

A

• Small vessel disease
- lacunar stroke (smokers)
• Hypoperfusion - blood flow related
• Large vessel atheroma/thrombosis - plaques in vessels
• Cardio-embolism - myocardial infarct affecting the endocardium/atrial fibrillation can cause ischaemic stroke

12
Q

What is a lacunar stroke?

A
  • Type of ischaemic stroke in deep areas when small perforating vessels get blocked (usually basal nuclei or internal capsule)
  • Gaps/cavities are left in the brain when necrotic tissue is resorbed
13
Q

Describe the progression of ischaemic stroke

A
  • Core is where the permanent damage is

* Penumbra surrounds the core, neurones in the penumbra can be saved

14
Q

What is the watershed area?

A
  • The most vulnerable area, if blood flow is reduced, theses areas will die first:
  • Cortical border zone
  • Internal border zone
  • Cortical border zone
15
Q

What does FAST stand for?

A

• Face - has it fallen on one side?
• Arms - can they raise both arms and keep them there?
• Speech - is it slurred?
• Time - call 99
(• check their glucose - can mimic a stroke)

16
Q

Describe examination in vascular neurology

A
  • BP and pulse measurement in 2 arms
  • Level of consciousness
  • Cardiac and carotid bruits
  • Blood glucose level
  • Neck stiffness/meningism
  • Abnormal or involuntary movements
  • Any seizure like activity
  • Skin rash/infarcts e.g. vasculitis, papular rash
  • Specific neurological - eye movements, speech, visual fields, inattention, motor and sensory, gait assessment
17
Q

What are the different types of stroke classfications?

A
  • Oxford community stroke project: clinical symptoms
  • TOAST classification: mechanism
  • Carotid and vertebrobasilar territory
18
Q

For OCSP classification what do you need to check and when?

A
  • Pattern at the time of maximum deficit
  • Motor/sensory pathways (muscle power, sensation)
  • Visual pathways (field of vision)
  • Higher cortical functions (speech, spatial awareness)
  • Brainstem funcitons (swallowing, eye movement)
19
Q

What are the classifications of the OCSP classification?

A
  • Total anterior circulation syndrome (TACS)
  • Parietal Anterior Circualtion Syndrome (PACS)
  • Lacunar syndrome (LACS)
  • Posterior circulaitokn syndrome (POCS)
20
Q

Lacunar syndrome

A
  • Pure motor
  • Pure sensory
  • Sensorimotor
  • Ataxic hemiparesis
21
Q

Posterior circulation syndrome

A
  • Brainstem
  • Cerebellar
  • Isolated homonymous hemianopia
22
Q

Total Anterior Circulation Syndrome

A

• Triad of:

  • hemiparesis
  • Dysphasia
  • Homonymous hemianopia
23
Q

Partial anterior Circulation syndrome

A
  • 2 of the features of TACS or:
  • Dysphasia
  • Parietal lobe signs (e.g. inattention, agnosia, apraxia, agraphaesthesia, Alexia)
24
Q

Describe the ABCD^2 assessment

A
  • 7 point to predict early stroke post TIA
  • Age >/60 =1
  • Blood pressure: systolic >140 and/or diastolic >/90 =1
  • clinical features: unilateral weakness= 2; speech disturbance w/o weakness = 1
  • Duration of symptoms in minutes: >/60=2, 10-59= 1
  • Diabetes = 1
25
Q

What can mimic a stroke?

A
  • Seizure
  • Syncope
  • Sepsis
  • Space occupying lesion
  • Somatisation
  • hypoglycaemia
26
Q

What are the red flags?

A
  • No history
  • No risk factors
  • Young age
  • Seizure
  • Unusual headaches
27
Q

What are the common risk factors of stroke?

A
  • Hypertension
  • Ischaemic heart disease
  • Peripheral vascular disease
  • Transient ischaemic attack
  • Diabetes mellitus
28
Q

What investigations should be carried out if there is a suspected stroke?

A
  • Good history and examination
  • ECG/Holter
  • Cholesterol/autoimmune and thrombophilia screen
  • Carotid doppler
  • CT brain/MRI brain
  • Cerebral angiography
29
Q

What are the indications for an urgent head scan?

A
  • Depressed level of consciousness
  • Unexplained, progressive or fluctuating symptoms
  • Papilloedema, neck stiffness or fever
  • Severe headaches at onset
  • History of trauma prior to onset
  • Indication of thrombolysis or anticoagulation
  • History of anticoagulant treatment or known bleeding tendency
30
Q

In which type of stroke can mass effect be seen

A

Ischaemic stroke, after 4 hours

31
Q

Secondary prevention drug treatment

A
  • Antithrombolytics: clopidogrel or Aspirin and Dipyridamole (in atrial fib. Warfarin or NOAC)
  • Anti lipids if total cholesterol is >4.0mmol/l, treat with a statin
  • Target BP< 130/80 with a calcium channel blocker or thiazide diuretic or an ACE inhibitor
32
Q

Describe the management of a subarachnoid haemorrhage

A
• CT brain/ lumbar puncture if CT normal, look for bilirubin and xanthochromia, cerebral angiogram 
• Management: 
- intubate if severe hypoxaemia 
- 3l of NaCl per 24 hours 0.9%
- Keep MAP<130mmHg 
- Nimodipine 
- Codeine or tramadol for pain 
- Phenytoin if seizures have occurred 
- Antiemetics
33
Q

Describe the blood supply of the medulla

A
  • Medial: Anterior spinal
  • Lateral posterior: vertebral artery
  • Lateral anterior: Posterior inferior cerebellar
34
Q

Describe the blood supply of the pons

A
  • Medial: Basilar
  • Lateral posterior: branches of the basilar
  • Lateral anterior: Branches from the basilar and anterior inferior cerebellar
35
Q

Midbrain blood supply

A
  • Medial: Basilar, posterior cerebral, posterior communicating
  • Anterior lateral: Branched from the posterior cerebral
  • Posterior lateral: posterior cerebral, superior cerebellar