Flashcards in Stroke Deck (13):
1
Ischemia pathology- lack of blood
• Most common type of stroke affecting all ages
• Usually caused by embolism with thrombus originating elsewhere- usually heart
• Thrombotic stroke accounts for ~50% of all strokes- clot originates in brain, limiting blood flow
• Brain tissue fails to function if deprived of oxygen for 60-90+ seconds
• Irreversible injury after ~3 hours, possible infarction
2
Pathology Haemorrhagic stroke- bleeding
• Weakened vessels rupture, leading to bleeding into surrounding brain
• Pressure may lead to loss of blood supply >> infarction
• Blood appears to have toxic effects on brain tissue
• Inflammation contributes to secondary brain injury
• Aneurysm (excessive swelling of vessel wall) or AVM (cluster of abnormally formed vessels) may cause blood vessel weakening
• Blood accumulates and compresses surrounding brain tissue
• 2 types: intracerebral (within brain); subarachnoid, (bleed into subarachnoid space)
3
Pathology Ischaemic transient attack
• Caused by blood clot, but blockage is temporary
• Symptoms occur rapidly and last for short time
• Usually no permanent damage
4
Signs of stroke
• Weakness, numbness or paralysis of face, arm or leg on either side
• Difficulty speaking or understanding
• Dizziness, loss of balance or unexplained fall
• Loss, blurred or decreased vision in 1 or both eyes
• Severe headache
• Difficulty swallowing
5
Diagnosis
• FAST- Face, arm, speech, time
• Neurological examination
• Imaging- ischemic stroke appears black, haemorrhagic stroke appears white; angiogram also specifies where blockage is
• Goals of imaging- differentiation of type and irreversibly affected/reversibly impaired tissue; identify stenosis or occlusion of arteries
6
Diagnosis of stroke in neurological exam
o Medical history
o Muscle strength
o Sensation
o Coordination
o Proprioception
o Reflexes
o Vision
o Neglect
o Spasticity
o Gait
o Transfers
7
Clinical features
• Deficits dependant on area affected by stroke- include: strength, coordination, sensation, vision and cognition
• If middle cerebral artery is affected, severe sensorimotor deficit in contralateral face and upper limb occurs
• Dominant hemisphere involvement may = global aphasia
• Non-dominant hemisphere involvement may = neglect syndrome
• Anterior cerebral artery = contralateral leg weakness and sensory loss
• Posterior cerebral artery = vision
• Basilar artery = cerebellum (incoordination, vertigo, nausea
8
Aphasia
• Damage to portion of brain responsible for language
• Left hemisphere for most people
• Difficulty expressing oneself when speaking or writing = expressive aphasia
• Trouble understanding speech or writing = receptive aphasia
9
Hemispatial neglect
• Reduced awareness of stimuli on one side of space despite no sensory loss
• Common during unilateral injury, particularly on right hemisphere
• Patients aren’t aware or acknowledge items on contralateral side
10
Management of acute stroke
• Likely pathology and cause
• Area of loss of blood
• Improve blood flow to ischaemic region- intravenous thrombolysis
• Time from onset of symptoms to treatment is critical
• Manage acute medical or neurological complications
• Manage risk of recurrent stroke
11
Physiotherapy management
• Mobilisation should begin ASAP to reduce complications- pneumonia, DVT, pulmonary embolus, pressure sores
• Rehab to restore neurological function
12
Treatment in rehab
• Neuroplasticity = underlying mechanism for stroke rehabilitation
• Requires learning of new task or skill and should be functionally relevant and engaging for patient
• Various techniques:
o Constraint induced movement therapy
o Bobath therapy
o Motor/mental imagery
o Mirror therapy
• Compensation strategies
• Initial severity of impairments and individual characteristics key predictors of stroke recovery outcomes
13