Stroke Flashcards
What is the definition of stroke?
A sudden onset of focal or global neurological symptoms caused by ischameia or haemorrhage which lasts >24hrs.
What is the most common type of stroke?
Ischaemic
How long do symptoms of TIAs usually resolve in?
1-60 mins
What is the time period that TIAs are defined by?
Symptoms lasting < 24hrs
What are the main causes of ischaemic stroke?
Large artery atherosclerosis
Cardioembolic
Small artery occlusion
Arterial dissection
What are the main causes of haemorrhagic stroke?
Primary intracerebral haemorrhage
Secondary (SAH, AV malformation)
What imaging would you use in stroke?
CT (acute)
MRI
What is the pathophysiology behind an ischaemic stroke?
Failure of cerebral blood flow due to interruption. This causes hypoxia and
Ischaemic penumbra.
When there is no oxygen (anoxia), infarction occurs & cell death.
What are some of the modifiable risk factors for stroke?
Smoking Hypertension Diet Cholesterols Exercise Obesity Diabetes
What are some of the non-modifiable risk factors for stroke?
> Age
Male
Family history
Previous history of stroke
What is the most important modifiable risk factor for stroke?
HYPERTENSION
What is the name of the small end arteries?
Lacunar arteries
What area of the brain will be affected in a receptive dysphagia?
Wernickes area
What area of the brain will be affected in a expressive dysphagia?
Brocas Area
If the ACA is blocked, where will symptoms be observed?
Legs
IF the MCA is blocked, where will symptoms be observed?
Arms, hands, face
What arteries comprise the anterior circulation of the brain? What is their origin
ACA
MCA
ICA
What arteries comprise the posterior circulation of the brain? What is their origin
PCA
(2 verebral arteries which form basilar)
3 cerebellar arteries
What arteries are responsible for the anatostomoses that comprise the Circle of Willis?
Anterior & posterior communicating arteries
Where does the anterior circulation of the brain arise?
ICA
What are the symptoms of ACA occlusion?
Contralateral foot & leg paralysis
Sensory loss
Impairment of gait
What are some of the symptoms of MCA occlusion?
Contralateral:
Leg/Arm/Face paralysis & loss of sensation
Homonymous hemianopia
Gaze paralysis
Aphasia (if affected dominant hemisphere)
Unilateral neglect & agnosia
If a stroke affects the Left side of the brain, what will be observed?
Dysphagia
Homonymous hemianopia
Right sides hemiplegia
What artery supplies the internal capsule?
MCA
What symptoms will be observed in a stroke on the right side of brain?
Left hemiplegia Homonymous hemianopia Visual & sensory agnosia Anasagnosia Prosapagnosia
What is hemiparesis?
Loss of motor function on one side of body
What are some of the symptoms of a lacunar artery stroke?
Pure motor
Pure sensory
Dysarthria
Ataxic hemiparesis
What are some of the symptoms of a PCA stroke?
Vertigo Coma Nausea, vomiting Hemiparesis & sensory loss Visual field defects
What are the different stroke classifications?
TACS
PACS
LACS
POCS
What is the most effective stroke treatment in first 3 hrs?
Thrombolytic therapy (TPA)
What type of treatment can be used in large vessel occlusions?
Thrombectomy (clot retrieval)
Who are the different people present on a stoke unit?
Stroke nurse Physio OT Speech & language therapist Dietician Psychologist
What are the strict criteria for TPA use?
< 4.5 hrs onset of symptoms
Have to show disabling neulogical deficits
Symptoms > 1hr
What may prevent the use of TPA?
Any signs of haemorrhagic/ bleeding tendency
For what stroke types can TPA be used?
Ischaemic
What investigations may you do in stroke patient?
Bloods (FBC, Glucose, lipids)
CT or MRI head scan
ECG
Anterior circular - carotid doppler US scan
Echocardiogram
Cerebral angiogram
What treatment may be given to someone following TIA to prevent stroke?
Antihypertensives
Antiplatelets
Statins
Endarterectomy
What are the differentials for a stroke?
Hypoglycaemia Post-ictal state Intracranial mass Vestibular disease Migraine Demented patient with UTI Bell's palsy
What preventative drugs would be given after?
Anti-hypertensives
Anti-platelets
Statins
(Anti-coagulate in AF)
What does ischaemia mean?
Lack of blood flow
What does hypoxia mean?
Lack of oxygen
The interruption of blood flow to the brain can be defined by Virchows triad whats this?
Vessel wall
Change in blood flow
Change in blood constituents
What are the 3 main causes of localised interrupted blood flow?
Atheroma + thrombosis
Thromboembolism
Aneurysm
If thrombus is present in ICA, which cerebral artery will be affected?
MCA
Where will a thromboembolism usually originate?
Left atrium in those with AF
What arteries will it move through until it reaches the brain?
Left atrium > Common carotid artery > ICA > MCA
If rupture of cerebral artery occurs, what will be observed?
Haemorrhage
Distal ischaemia
Where are the 2 most common sites of haemorrhagic stroke?
Basal ganglia (microaneurysms) Circle of Willis (berry aneurysms)
What are 3 examples of brain injury caused by generalised interrupted blood flow?
Hypotension
Cardiac arrest
Complex case
When will Watershed infarcts present?
When there is poor perfusion with oxygenated blood
What are Watershed infarcts?
Areas of ischaemias that are present at the zonal territory of arterial supply
What will hypotension at the brain result in?
Watershed infarcts
What will cardiac arrest result in?
Cortical infarcts
What will complex cases result in?
Complex infarction pattern