Week 4 Flashcards
Discusss the different definitions of conciousness
The term is ambiguous but means
Being self aware, awake and alert
Responsive to stimuli and aware of their surroundings and responses.
Key brain regions involved in the control of conciousness
The reticular activating system (RAS) HAS. Key control in the control of conciousness because it maintains arousal, and the waking state.
Ras consists of most of the brain stem areas and the thalamus. Additionally some projections from the posterior hypothalamus, which is involved in the control of the sleep-awake cycle
Ras influences decend the spinal cord and ascend the cerebral cortex.
The ras receives motor info from higher brain regions
Name the actual and chronic levels of conciousness and briefly outline them
Altered lvls of conciousness develop when the ras activity becomes greatly diminished
Acute: fully concious, confusion, delirium, lethargy, obtundation, stupor, coma.
Chronic: locked in syndrome or vegetable state
Clinical texts used to access conciousness
Avpu, gcs
Neurological status can be tested by testing cranial nerves
Define cva
State the main types
Identify key risk factors
Outline pathogen of this condition
Cerebrovascular accident, known commonly as a stroke,is a localised vascular lesion that develops suddenly within the cerebral circulation where the vessel becomes blocked or bleeds. -> cerebral Infarction and irreversible damage
Main types: Ischaemic and haemorrhagic.
Ischaemic: Sudden obstruction in cerebral artery leading to Ischaemia then Infarction. Thrombus is associated with the formation of an atherosceotic plaque (a blood clot). An embolus is any foreign material that travels within the body.
Haemorrhagic: cerebral arety ruptures causing a bleed in the brain. Risk is strongly associated with chronic hypertension, structurL weakness such as aneurysm, ateriovenous malformation (avm)
Describe the clinical manifestations, diagnosis, and prehospital management of CVA and large vessel occlusion
Rosier
Act positive means large vessel occlusion
Transport is treatment, and you also want to maintain perfusion
Outline the research behind the rosier score to correctly identify a potential cva prehospital environment
Explain the individual components of the rosier score to correctly identify a potential cva within the prehospital setting
Identify symptoms onset
Has there been loss of conciousness or syncope? -1
Has there been any seizure activity? -1
Asymmetrical facial weakness +1
Asymmetrical arm weakness +1
Asymmetrical leg weakness +1
Speech disturbance +1
Visual field defect + 1
= rosier score
Also need to gather bgl and premorbid independence?
Act = arm chat tap
Checks for large vessel occlusion
If Right arm weakness (you chat to your right hand man) - check for Severe language deficit (mute, gibberish, incomprehensible)
If left arm weakness, tap them and see if there is obvious gaze deviation of both eyes away from weak side or failure to turn to weak side when tapped.
ROSIER + = consider eligibility for code stroke notification
Rosier + Act positive = consider transport to RAH
Describe a transient ischaemic attack (TIA)
Has the same symptoms of a stroke but they go away
Still need transport so it can be distinguished from a stroke
Usually only lasts a few minutes (but can last hours)
Temporary blockage of blood flow in cerebral artery.
Dissolves or gets dislodged
Doesn’t cause permanent damage, but is a warning sign for a stroke.
Three parted brain
Lizard brain: brain stem and cerebellum, autopilot fight and flight
Mammal brain: limbic system, emotions, memories, habits, attachments
Human brain: neo-cortex, language, abstract, thought, imagination, conciousness, reasoning/rationalisation
Intracranial causes of Loc
Related to direct impact on anatomical structures
Head injury
Haemorrhage
Degenerative conditions
Space occupying lesions
Increased intracranial pressure
Vasospasm of cerebral vasculature
Extracranial causes of loc
Related to insults originating outside the cranium
Hypoxia
Hypertension
Profound hypotension
Systemic infection
Hepatic or renal dysfunction
Hypo/erglycaemia
Electrolyte imbalance
PH imbalance
Medications and other chemicals
AEIOU TIPS
Why is this person unconscious?
Alcohol
Epilepsy/electrolytes
Insulin
Overdose, oxygen
Underdone, udeamia (Kidney disfunction)
Trauma
Infection
Psychosis, psuedoseizure
Stroke, sepsis
