causes of ABI
- accident
- hypoxia
- stroke
- drugs and alcohol
onset of ABI
sudden - cerebral hypoxia, trauma
insidious - pronolonged drug abuse
causes and risk factors
- advanced age
- DM
- smoking
- pregnany
subtypes of stroke
ischaemic
* thrombus, embolus
* 80%
* decrease supply of arterial blood
haemorrhagic
* haemorhage
* 20%
* surrounding tissue is compressed
pathophysiology of ischaemic sroke
- decreased blood flow
- glucose and O2 deprivation
- no ATP
- changes to Na+, K+, Ca2+ ion concentrations
- inflammatory processes increase
- water flow into neurons
- K+ flows out, Na+ flows into cells
- ion channels stop working
two types of haemorrhagic stroke
intracerebral haemorrhage (ICH)
* bleeding directly into the brain parenchyma
subarachnoid haemorrhage
* bleeding into the cerebrospinal fluid within the subarachnoid space that surrounds the brain
pathophysiology of a haemorrhagic stroke
- rupture of blood vessels leads to break in the wall of a blood vessel
- subarachnoid - bleeding under the thin, delicate arachnoid membrane
- intracerebral - bleeding within brain itself
what is transient ischaemic stroke
- mini stroke
- similar to ischaemic but interruptin of blood flow temporary
signs/ symptoms of a stroke
- limb weakness
- dizziness, loss of coordination
- sezuires
- headache
- change in vision
clinical manifestation of a stroke
- lobe - vision issues
- occipital - loss of sensation, issues with spatial tasks
- frontal - emotional control, social skills, speech
- temporal - understanding and remembering language
- brain stem - physical and sensory problems
- cerebellum - coordination balance or muscle tone
recongising a stroke
BEFAST
* balance
* eyes
* face
* arms
* speech
* time
management of a ischamic stroke
- stabilise patient
- determining eligibility
- determining the pathophysiologic basic of the stroke
management of haemorrhage stroke
- stabilist patient - basic life support, control bleed, control seizures
- maintain BP and vitals
- reduce intracranial pressure
- drugs
living with brain injury
- ABI - also called hidden disability
- changes to physical and mental function
- coping with loss
- caring for family with an ABI
the brain structures
cerebrum
* compossed right and left hemisphere
* performs higher level functions
* hearing, vision, speech, emotions
cerebellum
* functions include coordination of muscle movements, posture and balance
brainstem
* responsible for automatic functions such as HR, repsiration, BP, temp, circadian cycles
the lobes of the brain
frontal lobe
* thinking, planning, organising, emotions
motor cortex
* movement
sensory cortex
* sensations
parietal lobe
* perception, making sense of the world, spelling
occipital lobe
* vision
temporal lobe
* memory, understanding language
what is blood brain barrier (BBB)
- protects the brain
- the nervous tissue is seperated from the general circulation by the BBB
- prevents the corssing of foreign substances, toxins and infection
- seperates circulating blood with cerebrospinal fluid
what are neurons
- cells of the nervous system, transmit messages via chemicals when triggered by an electricl stimulus
- the chemicals transmitted are - neurotransmitters
- electrical stimulus is - action potential
neurotransmitters
- synthezised within neurons and allows neurons to communicate
- neurotransmitters amplify or modulate signals
- excitatory will enhance
- inhibitory will inihibit or reduce the response
what is the synpatic junction
- the synapse is the point of junction between 2 neurons
what is excitatory and inhibitory
excitatory
* chemicals which stimulate AP - glutamate
inhibitatory
* chemicals stop the ion channels from opening, AP to not be generated - GABA
causes of epilepsy
- stroke
- head injury
- genetics
- infections
what are seizures
- abnormal electrical activity in the brain causes involuntary change in the body movement, sensation, awareness or behaviour
- there is a momentary “imbalance” within electrical and chemical circuits in the brain
what are seizure triggers
- illicit drugs
- lack of sleep
- missed medication
- diet and caffeine
- alcohol
- illness/ infections
- menstruation
