Flashcards in Quiz 1 - definitions, substrates, evaluation of consciousness Deck (53)
pupils in damage to caudal levels of midbrain
- CNIII damage as in mesencephalon
- added damage to sympathetics
- pupils midsized (4-7mm)
- no reaction to light
pupils in damage to pons/medulla
- same as midbrain
- midsize and fixed
pupils in isolated pons or isolated medulla damage with maintained integrity of midbrain
- only loss of sympathetics
- very constricted pupils (1mm or less)
pupils in suppression of brainstem by drugs
- loss of light reflex
what happens in auditory ice water test if reticular formation is functional but there is diffuse cerebral damage?
- eyes go toward ice water side and stay there for minutes
- no nystagmus
in terms of eye movement, diffuse damage to cerebral cortex results in loss of.....
- fast component of vestibulo-ocular reflex (nystagmus)
- degree of suppression is proportionate to degree of damage
eye movements in damage to midbrain
dysconjugate eye movements
tonic conjugate deviation of the eyes during caloric stimulation indicates that....
the brainstem/reticular activating system is still intact
eye movement in damage to brainstem through the pons
- no reaction at all to caloric stimulation
- no corneal reflex
how will a lightly stuporous patient react to noxious stimuli?
- localize it
- knock it away or grab it
how will a deep stupor patient react to noxious stimuli?
- withdrawal (stereotyped)
noxious stimulation reaction of a comatose patient with damage to diencephalon
elements of decorticate posturing
- flexion of arms, wrists, fingers
- extension of lower limps
- may be asymmetric at first, appearing first on side of greater damage
noxious stimulation reaction of a comatose patient with damage to mesencephalon or upper pons
elements of decerebrate posturing
extension and internal rotation of arms and legs
what motor response is usually seen in pontine and medullary damage?
last reflex that can still be detected as metabolic dysfunction progresses
5 categories of metabolic dysfunction
examples of toxic metabolic dysfunction
endogenous - liver, kidney failure
exogenous - drug overdose
CNS - meningitis, encephalitis
what is most commonly the cause of depressed consciousness in a demented patient?
- demented patient's remaining cortical function is much more sensitive to stressors such as renal dysfunction, infections, drugs...
two major causes of vegetative state
- hypoxic ischemia
- shear force from trauma
are those in vegetative state conscious? aware?
no and no