Stroke Flashcards
What is stroke?
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
Describe the pathophysiology and consequences of stroke?
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)
What’s the difference between stroke & transient ischaemic attack (TIA)?
TIA is defined by ‘stroke (mini stroke) symptoms that resolve completely within 24 hours’ (WHO)
risk factors of stroke?
inactivity hypertension heart disease diabetes smoking obesity previous stroke & TIA
blood supply in the brain, where do the following arteries supply blood to? Carotid arteries Vertebral arteries Basilar artery Communicating arteries
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
what are the different types/causes of stroke?
ischemic stroke (75-85%)
Haemorrhagic Stroke
Transient Ischemic Attack (TIA) – Mini stroke
Which arteries can be affected by thrombosis (blood clot)?
Large arteries: carotid, vertebral & basilar
Larger branches: anterior, middle & posterior cerebral arteries
Small arteries: small branches from the above larger branches
What sort of damage can Ischemic stroke/thrombosis have?
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
What is Ischemic stroke/Embolism? What can cause it?
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
Haemorrhagic stroke is divided into two, what are they?
Intracerebral and Subarachnoid bleeding.
What is Intracerebral bleeding?
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
What is subarachnoid bleeding?
Bleeding at the surface of the brain due to aneurysm rupture.
Most of the aneurysm occur in circle of Willis
Surgical intervention required
What are the risk factors for an aneurysm?
Smoking, alcohol, hypertension, genetic, drug abuse, therapeutic drugs-anticoagulants
What are the two types of aneurysm?
Saccular (berry)
Fusiform
What are the symptoms of stroke?
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
What are the recognising symptoms of stroke? Campaign?
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