Consciousness and Brain Injury Flashcards
MEASURING (UN)CONSCIOUSNESS - GLASGOW COMA SCALE
- Designed to assess after brain injury (stroke, TBI, overdose, infection, seizures, etc)
- Eye Opening (1-4 scale)
- Verbal Response (1-5 scale)
- Motor Response (1-6 scale)
- (Ignore element if ‘local factor’ impairs response)
GCS PROCEDURE:
Check: any confounders (e.g. deaf, eye swelling, sedation, intubation)
Observe: spontaneous behaviours in each of the three criteria
Stimulate: verbal stimulus, then physical stimulus (e.g. squeeze fingers, trapezius muscle, thumb into supraorbital notch)
Rate
GCS SCORES RANGE:
3 = General Anaesthesia (no response on anything)
4-6 = Vegetative State
11-12 = Locked in Syndrome
15 = Fully conscious and alert
3-15 = Head Injury, Stroke, Hypoglycaemia, Intoxication,
LOCKED-IN SYNDROME:
- Fully cognitivelt able
- All muscles paralysed
- Brainstem damage only (stroke, tumour, venom poisons)
- Little or no recovery in most cases
- GCS score 11-12 (not really useful; completely conscious?)
CHRONIC TRAUMATIC ENCEPHALOPATHY:
- Dementia associated with repeated head injury (Contact sports, domestic violence)
- Similar cognitive problems to other dementias
- Early age of onset
- Mood changes striking feature (Aggression, apathy)
- Increased recognition
CONCUSSION:
- GCS 13-15
- Mild TBI
- Impact and/or rapid acceleration/deacceleration
- Scans may appear normal (functional rather than structural)
- Confusion, dizziness, transient amnesia
- Shear stress on neurons
CONCUSSION TIMELINE:
- Shear stress opens ion channels in large numbers
- Causes firing, massive glutamate release
- Causes further depolarisation
- Na+/K+ exchanger massive increase in activity
1. Massive jump in glucose metabolism (mins – hours)
2. (cellular energy crisis)
3. Hypometabolism (hours – days) (Affects cognition if concussion is in relevant areas (PFC, hippocampus))
VEGETATIVE STATE GCS SCORES:
- GCS score 4-6
- Sleep-wake cycle preserved (hence open/close eyes, score 3-4 on eye opening)
- Non-verbal (score 1 on verbal)
- Motor responses limited (e.g. to pain)
VEGETATIVE STATE PRESENTATION:
- ‘wakeful unconscious state lasting longer than a few weeks’
- Considered permanent after 12 months
- Artificial feeding
- Brainstem active and so maintains other functions
FRONTOTEMPORAL DEMENTIA
- Most common form of dementia in patients under age 65 (though still very rare)
- 20% have known familial cause
- 40% have strong family history
- Poor outlook (Limited treatment options and Slow progression)
- Often restricted to one hemisphere
VARIANTS OF FTD:
Primary progressive aphasia (PPA)
- Non-fluent agrammatic PPA – difficulty forming sentences, effortful halting speech
- Semantic PPA – fluent but non-sensical speech
- Lopogenic PPA – difficulty retrieving words, slow and effortful
Behavioural variant FTD
- Progressive deterioration of behaviour/cognition
- Behavioural disinhibition
- Apathy/inertia
- Loss of sympathy/empathy
- Decline of executive function (Memory is largely spared (contrast with Alzheimer’s dementia), Verbal/language impairment)
- Changes in diet
- (Not psychiatric)
57% of people with bvFTD have committed a crime.
ANTISOCIAL PERSONALITY DISORDER:
- Pervasive disregard for and violation of the rights of others
- Three or more of
1. Lawbreaking
2. Lying
3. Impulsive
4. Irritable + aggressive
5. Reckless disregard for safety of self/others
6. Irresponsible (e.g financial, unreliable at work)
7. Lack of remorse - At least 18, with conduct disorder <15
- Not schizophrenia or bipolar
- More common in men than women
- More likely to abuse alcohol/drugs
- Spectrum of severity (psychopathy considered ‘extreme ASPD’
- Symptoms may fade slightly with age
- Limited medication options
- 1-4% of the population
To be guilty of a crime requires:
Criminal act
Guilty mind
No defence
