Week 3 Lecture 5: Brain Death Flashcards
How is wakefulness produced?
activity of reticular activating substance from the brain stem produces wakefulness
What is consciousness?
- awareness of self and environment
- alertness
- making appropriate and differential responses
- thinking, feeling, functioning, planning and self monitoring
What does quadriplegic mean?
paralysis of all 4 limbs
what does areflexic mean?
muscles dont respond to stimuli
What does ophthalmoplegic mean?
not moving eyes
what is miller-fisher syndrome?
- immunological injury to peripheral nerves
- treated with IV immunoglobulins
- characterized by abnormal muscle coordination, paralysis of the eye muscles, and absence of the tendon reflexes
What are the 6 stages of conciousness and what does each one mean?
- hyperalertness - state of overarousal seen in mania and anxiety
- alertness - normal state of wakefulness
- somnolence - drowsy pre-sleep state / decreased attention
- sopor - confused/ cannot be easily alerted
- stupor - can be semi roused only by vigorous stimulation
- coma - cannot be roused, reflexes diminished or absent
What is the definition of a coma?
- eyes do not open spontaneously or to external stimulation
- patient does not follow commands or speak
- patient does not show intentional movement
- cannot sustain visual pursuit movement of the eyes through a 45* arc in any direction
Whats the most common cause of coma?
supratentorial lesions (lesions above the tentorium cerebelli)
what is locked in syndrome?
- aware and awake, able to breath
- cannot move or speak
- damage to ventral pons
- usually a result of brainstem (basilar territory) stroke
- no cure, recovery is rare
- can feel pain, touch and position of limbs
What is a vegetative state?
No evidence of:
- awareness of self or environment or ability to interact with others
- sustained purposeful or voluntary behaviours either spontaneously or in response to stimuli in any sensory modality
- language, comprehension or meaningful expression
- unconscious and unaware
- unresponsive to external stimuli
When is a persistent vegetative state diagnosed?
diagnosed if no change at 30 days
What are the 3 persistent disorders of consciousness?
- coma - completely unconsciousness
- PVS - reflexive, automatic and spontaneous behaviours may be observed but there is no awareness
- MCS (minimally conscious state) - severely altered consciousness
why do younger people show better signs of recovery from brain injury?
brain is more neuroplastic
What is neuroplasticity?
ability of neural networks in the brain to change through growth or reorganisation
