Stroke Flashcards

1
Q

What is stroke?

A

is a rapid death of brain tissue due to a disturbance in blood supply
WHO = neurological deficit of cerebrovascular cause that persists beyond 24 hours or is interrupted by death within 24 hours’

3rd most common cause of death in the UK after CHD and cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the pathophysiology and consequences of stroke?

A

Interruption of blood supply to the brain
Rapid necrosis of neurons in the central core
Inflammation and apoptosis and excitotoxicity in surrounding area (penumbral areas)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What’s the difference between stroke & transient ischaemic attack (TIA)?

A

TIA is defined by ‘stroke (mini stroke) symptoms that resolve completely within 24 hours’ (WHO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

risk factors of stroke?

A
inactivity
hypertension 
heart disease
diabetes
smoking
obesity
previous stroke & TIA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
blood supply in the brain, where do the following arteries supply blood to?
Carotid arteries
Vertebral arteries
Basilar artery
Communicating arteries
A

Carotid arteries: Anterior supply for front and middle regions of the brain

Vertebral arteries: Posterior supply to brain stem and rear regions of the brain

Basilar artery: two vertebral joins together

Communicating arteries: Posterior (basilar-carotid) & Anterior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the different types/causes of stroke?

A

ischemic stroke (75-85%)
Haemorrhagic Stroke
Transient Ischemic Attack (TIA) – Mini stroke

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which arteries can be affected by thrombosis (blood clot)?

A

Large arteries: carotid, vertebral & basilar
Larger branches: anterior, middle & posterior cerebral arteries
Small arteries: small branches from the above larger branches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What sort of damage can Ischemic stroke/thrombosis have?

A

Atherosclerotic plaque rupture leads to thrombosis
Interrupts blood supply (oxygen, glucose & other nutrients) to neurons
Rapid death of brain tissues leads to loss of brain function
Changes can be observed within 2-3 hours of ischemia
Complete death of brain tissues can occur within 6-24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is Ischemic stroke/Embolism? What can cause it?

A

Embolism = lodging of an embolus, a blockage-causing piece of material

Heart is a common source of emboli to the brain. Common conditions to form clots in the left ventricle: congestive heart failure and heart attack

Blood stasis leads to thrombosis

Thrombus may stick to ventricle wall and become embolized

Emboli breaks up into pieces = blocks arteries = stroke

Atrial fibrilation = left atrium less effective in ejection of blood = blood stasis etc

Endocarditis = fungal or bacterial growth (septicaemia) in heart valve forms lumps and emboli in the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Haemorrhagic stroke is divided into two, what are they?

A

Intracerebral and Subarachnoid bleeding.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is Intracerebral bleeding?

A

Bleeding within the brain - due to hypertension, trauma, bleeding disorders and vascular defects

High pressure in arteriovenous malformation causes rupture and bleeding forms haematoma

This compress/ ruptures/ damages neurons - irreversible damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is subarachnoid bleeding?

A

Bleeding at the surface of the brain due to aneurysm rupture.
Most of the aneurysm occur in circle of Willis
Surgical intervention required

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the risk factors for an aneurysm?

A

Smoking, alcohol, hypertension, genetic, drug abuse, therapeutic drugs-anticoagulants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the two types of aneurysm?

A

Saccular (berry)

Fusiform

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the symptoms of stroke?

A

Loss of consciousness
Worst headache of their life
Double vision or Loss of vision
Slurred speech or Loss of speech

Numbness of face/arm/leg on one side
Weakness of face/arm/leg on one side
Loss of balance or coordination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the recognising symptoms of stroke? Campaign?

A

F - face - has their face fallen on one side
A - arms - can they raise both arms and keep them there
S - speech- is the speech slurred
T - time to call 999 if you see ANY SINGLE sign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Assessment of the risk for a stroke following TIA

A

ABCD2, a prognostic score to identify people at high risk of stroke after a TIA
A - age: 60years of age or more = 1point
B- blood pressure at presentation: 140/90mmHg or greater = 1point
C- clinical features: unilateral weakness = 2points;
speech disturbance without weakness = 1point
D- duration of symptoms: 10 - 59minutes = 1point;
60 minutes or longer = 2points
presence of diabetes: 1point

18
Q

Describe the score outline for ABCD2 assessment

A

ABCD2 score ≥ 4 = high risk of stroke
aspirin (300 mg daily) started immediately
specialist assessment
investigation within 24 hours of TIA symptoms

19
Q

What limitations does the use of the ABCD2 assessment have?

A

cannot be used in patients with recurrent TIA or on

anticoagulant treatment

20
Q

What test is used in A&E to recognise stroke?

A

ROSIER scale

21
Q

What are the management strategies of stroke?

A

Rapid recognition of symptoms and diagnosis
Rapid action essential to enhance patient survival
Assess risk of stroke in patients with TIA
Specialist care for people with acute stroke
Brain imaging (CT or MRI scan)
Pharmacological approaches:
All existing treatments aim to prevent further strokes
Prevent further neuronal loss (neuroprotection)
Repair/Replace damaged neurones (neurorestoration)

22
Q

What is the pharmacological management after TIA if the patient has a high ABCD2 score = 4 or above?

A

Aspirin 300mg daily start immediately
Specialist assessment & investigation within 24 hours following onset of symptoms
Measures for secondary prevention including the assessment of individuals risk factors
Crescendo TIA (≥ 2/week) should be treated as high risk even if the score is <4

23
Q

What is the pharmacological management after TIA if the patient has a low ABCD2 score = 4 or less?

A

Specialist assessment within a week following onset of symptoms
Referral to brain imaging if needed

24
Q

What is the pharmacological management of ischemic stroke?

A

Use of thrombolytic agents
Tissue Plasminogen Activator (tPA)
Example : Alteplase (900µg/kg/1 hour)
Promotes the breakdown of fibrin (lysis of the blood clot)
IV administration within 4.5 hours of stroke improves clinical outcome (death or disability)

Can not be used in haemorrhagic stroke

Surgery to remove the plaques

25
Q

What is the Pharmacological Management of Acute Ischemic Stroke ?

A

Alteplase given within 4.5 hours, 900 microgram/kg/over 60 minutes and in specialist stroke centre or by trained staff
Aspirin started within 24 hours, 300mg daily for 2 weeks (oral or via rectal/enteral tube, if dysphagic; if history of dyspepsia, give proton pump inhibitor) or clopidogrel 75 mg daily as alternative (if aspirin-intolerant)
Modified-release dipyridamole in combination with aspirin if clopidogrel is contraindicated or not tolerated
Others include anticoagulants, antihypertensives, statins, surgeries to remove blockages and place stent

26
Q

What is the Pharmacological Management of Haemorrhagic Stroke?

A

Removal or clipping of aneurysm

Antihypertensives
Reversing anticoagulants (if any)

Surgery (craniotomy) to remove blood or haematoma

Surgery to treat hydrocephalus (to drain CSF)

27
Q

What does the Long-term Pharmacological Management of Stroke involve?

A

Long-term Clopidogrel 75 mg/daily
Note: Clopidogrel can be used in other cardiovascular conditions/ diseases if aspirin is contraindicated/ not tolerated

Modified Release (MR) dipyridamole (200 mg twice daily) in combination with aspirin (75 mg/once daily) should be used in people who have had
 a TIA
Ischemic stroke and Clopidogrel  is contraindicated/not tolerated.
28
Q

What are the stroke induced physical deficits?

A

Loss motor control
(Paralysis, Hemiplegia/hemiparesis)

Ataxia - uncoordinated muscle movements

Dysphagia

Visual/hearing loss

Sensory disturbances
(Pain, loss of bowel or bladder control)

29
Q

What are the stroke induced communicative deficits?

A

Dysphasia - difficulty using and understanding spoken and written language

Dysarthria - malfunction of muscles in face resulting in an inability to form words

Dysphonia - when a stroke affects the muscles in the voice box, changing the way the voice sounds and making it hard to moderate the voice

30
Q

What are the stroke induced cognitive deficits?

A

Agnosia - inability to recognise objects, people, sounds, shapes, smells

Dyspraxia - difficulty with complicated tasks, which means that the person may find it hard to speak or understand conversation

Impairments of:
attention
memory (Dementia)
perception
problem- solving
learning new tasks
31
Q

What are the stroke induced emotional deficits?

A

Depression

Anxiety disorder

Apathy

Psychosis, Mania

Bipolar disorder

32
Q

There are two areas of injury in ischaemic stroke, what are they?

A

Core ischemic zone’ & ‘Ischemic penumbra

33
Q

Describe the damage in the Core ischemic zone

A

lethally damaged area, low perfusion (<10-25%), depletion of energy due to loss of O2 & glucose, cells lost their membrane potential, necrosis of neurons & glial cells

34
Q

Describe the damage in the ischemic penumbra

A

area of restricted blood flow from collateral arteries, partial energy metabolism, cells depolarize intermittently, reperfusion must be restored quickly

35
Q

What is excitotoxicity?

A

Caused by increased synaptic level of glutamate
(↑release ↓re-uptake)

[Ca2+]i increases to abnormally high levels

Ca2+-dependent processes triggered which lead to cell death

Excitotoxicity responsible for neurodegenerative processes including Alzheimer’s, Amyotrophic lateral sclerosis, Huntington’s and Parkinson’s diseases

36
Q

What is glutamate and where is it found in?

A

an excitatory amino acid (EAA)
non essential AA
found in all protein-containing foods

37
Q

What is the function of glutamate?

A

Glutamate is the major excitatory transmitter in the brain
The major mediator of excitatory signals in the mammalian CNS
It regulates brain development, cellular survival, differentiation and normal brain functions

38
Q

What are the 3 main cellular and molecular changes following a stroke?

A
  1. Deprivation of oxygen and glucose
  2. Glutamate induces exitotoxicity
  3. Peri-infarct depolarisation
39
Q

Describe what happens when Deprivation of oxygen and glucose occurs.

A

Cells depolarize
Voltage‐dependent Ca2+ channels are activated
Release of glutamate into the synaptic cleft

40
Q

Describe what happens when Glutamate induces exitotoxicity

A

Activation of NMDA and mGluR receptors
Increase in intracellular Ca2
Initiation of ischaemic cell death & inflammation

41
Q

Describe what happens when Peri-infarct depolarisation occurs

A

Na+ and Cl- influx

Water passively enters Brain oedema

42
Q

What are the rehabilitation aims for stroke patients?

A
  1. Restoration of function (re-learning skills and abilities)
    Physiotherapy (e.g. learning to walk)
    Speech and language therapy (e.g. learning to talk)
    Occupational therapy (e.g. shopping)
    Psychologist/Psychiatrist (e.g. to adapt psychologically)
  2. Learning new skills
    e. g. occupational therapy
  3. Adapting to some of the limitations (caused by a stroke)
    e. g. smaller meals to avoid choking, physical changes to home, wearing incontinence pads, communicating in different ways, mobility aids
  4. Support network
    patience, positive, carers strike a balance between taking over and full independence