Introduction to Stroke (Week 1) Flashcards
What is the definition of a stroke?
- previously called cerebrovascular accident (CVA)
- acute onset of neurological deficit
- lasting > 24 hrs
- vascular cause
What is the definition of a transient ischaemic attack (TIA)/mini-stroke?
- acute onset of neurological deficit
- lasting < 24 hrs
- vascular cause
List the risk factors of a stroke.
- older age
- hypertension
- diabetes mellitus
- increased blood lipid levels
- obesity
- smoking
- family history
- male gender
What are the two types of ischemic stroke?
- atherothrombosis (30%)
- embolism (25%)
What causes an atherothrombosis?
- type of ischemic stroke
- build-up of artherosclerosis plaque that blocks blood flow
What causes an embolism?
- type of ischemic stroke
- most common cause is atrial fibrillation (can form blood clots/embolus in the heart) –> clots travel further up and get caught in one of the cerebral arteries)
What are the two types of haemorrhagic stroke?
- subarachnoid (5%)
- intracerebral (10%)
What causes a subarachnoid stroke?
- bursted aneurysm –> blood in subarachnoid space
What causes an intracerebral stroke?
- infarct (necrosis due to inadequete blood supply)
- chronic hypertension –> increased pressure –> haemorrhage
- intracerebral haemorrhage (occurs right inside the brain)
Primary impairments: sensori-motor
- dysphagia (difficulty with swallowing) - likely that stuff will end up down their trachea into their lungs, instead of going down the oesophagus (aspiration pneumonia)
- dysarthria (difficulty with articulation) - cannot produce comprehensible speech
Primary impairments: non-motor (vision impairment)
- hemianopia - loss of visual field on side of hemiplegia from both eyes
- quadrantanopia - loss of a quadrant of the visual field
- loss of conjugate gaze - problem with the coordination of eye movements e.g. double vision
Primary impairments: non-motor (speech/language impairment)
- aphasia/dysphagia - difficulty with the spoken word/can’t put words together
- receptive aphasia - trouble understanding
- expressive aphasia - trouble expressing
- global (both)
Primary impairments: non-motor (perceptual impairment)
- difficulty processing and interpreting sensory info
- includes neglect and agnosia
Primary impairments: non-motor (cognitive impairment)
- inability to process, sort, retrieve and interpret information (cognitive)
- includes problems with problem solving, motivation, planning, organisation, attention, and memory
- can require assessment and treatment from trained team members (neuropsychologist, OT, speech pathologist)
Primary impairments: non-motor (dyspraxia/apraxia)
- inability to plan/execute movements
Primary impairments: non-motor (behavioural/emotional impairments)
- lability - rapid, often exaggerated changes in mood e.g. uncontrollable laughing or crying
- depression
- anxiety
- impulsivity
- disinhibition
- personality changes - aggressive or passive behaviour
- decreased insight
- unrealistic goals
What is the definition of dysarthria?
- decreased intelligibility of speech due to motor cause
What is the definition of dyspraxia?
- impairment of motor planning
What is the definition of hemianopia?
- loss of vision of one half of visual field
What is the definition of aphasia?
- impairment of language
What is the definition of agnosia?
- inability to recognise objects
What is the definition of neglect?
- inattention to part of the environment
What is the definition of lability?
- excessive emotion
What is the definition of perception?
- ability to perceive and interpret sensory information
What are the 4 arterial trunks that supply the brain?
- anterior circulation: internal carotid artery system (internal carotid, external carotid, common carotid artery)
- posterior circulation: vertebro-basilar system (vertebral artery)
Describe the anterior circulation.
- the carotid system supplies the parietal, frontal, and temporal lobes and cortical deep white matter
- parietal and temporal lobe - impact on motor output, sensations, speech and language, planning, perception
- frontal lobe - behavioural impairments
Describe the posterior circulation.
- the vertebro-basilar system supplies the brain stem, cerebellum and occipital lobes
- no cortical effects (e.g. language, thought processes, behaviour, personality) [ANTERIOR]
What are the possible impairments of an anterior circulation stroke?
Sensori-motor:
- reduced strength
- reduced coordination
- reduced sensation
- spasticity
Non-motor:
- reduced vision
- reduced speech/language
- reduced perceptual function
- reduced cognitive function
- apraxia
- behaviour
- emotion
What are the possible impairments of a posterior circulation stroke?
Sensori-motor:
- reduced strength
- reduced coordination
- reduced sensation
- spasticity
- dysarthria
Non-motor:
- reduced vision
List the differences between a dominant and non-dominant stroke.
- most people have a dominant hemisphere - L) hemisphere dominance (90% of the population)
- L) hemisphere - language, analytical functions
- R) hemisphere - body awareness and visuo-spatial skills, attention e.g. neglect
What are the possible impairments of a L) dominant hemisphere anterior circulation stroke?
Sensori-motor:
- reduced R) strength
- reduced R) coordination
- reduced R) sensation
- R) spasticity
Non-motor:
- reduced R) vision
- reduced R) speech/language
- reduced R) cognitive function
- apraxia
- behaviour
- emotion
What are the possible impairments of a R) non-dominant hemisphere anterior circulation stroke?
Sensori-motor:
- reduced L) strength
- reduced L) coordination
- reduced L) sensation
- L) spasticity
Non-motor:
- reduced L) vision
- reduced L) perceptual function
- reduced L) cognitive function
- behaviour
- emotion
Behaviour characteristics that may impact learning
L) sided stroke / R) hemiplegia:
- good concentration
- slow movement time
- correct performance
- good carryover effect
- realistic attitude
- depressed, anxious, frustrated, can be labile
R) sided stroke / L) hemiplegia:
- poor/distractible concentration
- impulsive movement time
- erratic performance
- poor carryover effect
- unrealistic attitude
- may appear unmotivated, can be labile
What is the Bamford classification?
TA = total anterior PA = partial anterior L = lacunar PO = posterior
Code last letter as follows:
S = syndrome (indeterminate pathogenesis, prior to imaging e.g. TACS)
I = infarct e.g. TACI
H = hemorrhage e.g. TACH
What is TACS?
- total anterior circulation stroke
- all of the following three: hemiplegia +/- sensory loss, hemianopia, cortical signs e.g. cognitive, perceptual, aphasia
- most severe stroke
- 5% of patients alive and I at 1 yr
What is PACS?
- partial anterior circulation stroke
- two of the following three: hemiplegia +/- sensory loss, hemianopia, cortical signs e.g. cognitive, perceptual, aphasia OR isolated cortical dysfunction OR pure motor or sensory signs less severe than lacunar
- 55% of patients alive and I at 1 yr
What is LACS?
- lacunar stroke
- hemiplegia +/- sensory loss - affecting at least 2/3 of face/arm/leg
- no cortical signs
- 60% of patients alive and I at 1 yr
- occlusion of deep perforating arteries
What is POCS?
- posterior circulation stroke
- multitude of signs - can include the following: cranial nerve palsies, ips. motor and/or sensory impairments, bilateral motor +/- sensory deficits, eye movement disorders, isolated hemianopia, cerebellar deficits
- if patients survive the acute event - about 60% of patients alive and I at 1 yr
What are the symptoms of a R) TACS?
L) sided weakness, no sensory loss, L) hemianopia, L) sided neglect, dysarthria
What are the symptoms of a LACS?
R) sided weakness, L) sided sensory loss
What are the symptoms of a L) PACS?
R) sided weakness, aphasia
What are the symptoms of a L) TACS?
R) sided weakness/sensory loss, R) hemianopia, receptive dysphasia
What are the symptoms of a POCS?
L) sided weakness/sensory loss, nystagmus, bilateral loss of coordination, diplopia (double vision)
What is the interdisciplinary Mx of stroke?
- people with stroke have complex care needs
- stroke affects the individual and their carers and families
- ## interdisciplinary teams provide the best evidence-based care for people with stroke
What is the interdisciplinary Mx of stroke?
- a stroke unit brings together in one geographically located ward an interdisciplinary team of professionals with an interest and expertise in stroke care
- stroke team usually includes physicians, nurses, PTs, OTs, speech pathologists
- often also includes dieticians, social workers, orthoposts
- referral may be appropriate e.g. to psychology or psychiatry for people with mood disorders, to optometry for people with visual dysfunction
What is the role of a physician in stroke Mx?
- physician (usually a neurologist) oversees medical Mx (stable observations = better outcomes)
- identify cause of stroke
- attempt to prevent further stroke
- manage other medical conditions
What is the role of a nurse in stroke Mx?
- monitoring of neurological status and vital signs
- hydration monitoring and intravenous treatment
- medication
- assessment/Mx of continence, skin integrity, pain
- assistance with mobility, falls prevention and personal care
- prevention of complications
- info and support to patients and families
- palliative care for those who are terminally ill
- education about secondary prevention including smoking cessation
How can reperfusion help stroke Mx?
- most strokes are caused by a clot that occludes blood flow to the brain
- ischaemic penumbra is an area of compromised but still viable tissue surrounding the dead tissue
- removing the clot can restore blood flow to the ischaemic penumbra and improve patient outcomes
- options: intravenous thrombolysis, endovascular clot retrieval
- intravenous thrombolysis - drug that dissolves the clot/blood thinning medication
- endovascular clot retrieval (thrombectomy) - minimally invasive procedure, catheters goes through the groin blood vessels & advances all the way up into neck vessels and eventually to the brain
What is the role of OT in stroke Mx?
- ADLs - self care, RTW
- perceptual/cognitive/behavioural screening and Mx
What is the role of speech pathologists in stroke Mx?
- dysphagia
- communication problems
What is the role of social workers in stroke Mx?
- financial issues
- family issues
- services
- placement - aged care facilities
What is the role of an orthoptist in stroke Mx?
- visual problems
What is the role of a neuropsychologist in stroke Mx?
- cognitive assessment
