Coma CC5 Flashcards
Name an example of a normal alteration of consciousness?
sleep
If someone has a coma, you know what locations are impaired?
bilateral cortex or reticular activating system
What are the steps of COMA exam?
- Neuro exam of altered consciousness
- vital signs
- respiratory pattern
- Level of Consciousness
- Pupils
- Ocular movements
- Motor responses
What is cheyne-stokes respiration? Where is the lesion?
compressed time frame with waxing and waning character
-disrupted bilateral diencephalon or cortex
What are apneustic respirations? where is the lesion?
deep and fairly regular
lesions of midbrain near RAS by colliculus
-cut off voluntary breathing centers
What are ataxic respirations? Where is the lesion?
breathing is uncoordinated, but diaphragm is innervated
“breathing from their medulla”
-lesion in pontine tegmentum
What are the four levels of consciousness?
- normal - no external stim needed
- somnolent - external stim–> normal waking
- obtunded - external stim–>abnormal waking
- COMA - no wakefulness
What are metabolic pupils?
small and reactive
-downers
What are pupils like after lesion to diencephalon?
small and reactive
-no sympathetic stimulation
What are pupils like after a lesion to the tectum?
large and fixed - no pupillary light reaction
What are the pupils like after a lesion to the right oculomotor nerve?
Right eye is Dilated and fixed
- shine light in either eye, right wont constrict
- shine light in right eye, left will constrict (consensual of right in tact)
What are the pupils like after a lesion to the midbrain?
midposition, fixed and in a coma
What are the pupils like after a lesion to the pons?
pinpoint pupils
Where is the nuclei of the abducens nerves?
Pons
Where is the nuclei of the III cranial nerve?
midbrain
What is decorticate posturing?
abnormal flexor response of arms with extension of legs —- antigravity muscles
-lesion above the red nucleus
What is spastic hemiparesis?
disconnection of cortex from motor centers
-lesion above the level of red nucleus
(same as decorticate posturing)
What is decerebrate posturing?
abnormal extensor response of arm and legs
-antigravity mechanism for quads
-lesions caudal to red nucleus -release of vestibulospinal output
If there is a progressive lesion bilaterally in the diencephalons, what is the:
- respiratory pattern
- pupil status
- oculocephalic response
- motor response
- cheyne stokes
- small pupils with small range of contraction
- normal oculocephalic response, no nystagmus
- motionless or decorticate rigidity
If there is a progressive downward lesion that hits bilaterally in the midbrain, what is the:
- respiratory pattern
- pupil status
- oculocephalic response
- motor response
- sustained regular hyperventilations
- fixed pupils in midposition and irregular shape
- dysconjugate oculocephalic response
- medial rectus isnt functioning - motionless or decerebrate
If there is a progressive downward lesion that hits bilaterally in the pons, what is the:
- respiratory pattern
- pupil status
- oculocephalic response
- motor response
- more shallow and rapid, or slow and irregular
- pupils at midposition and fixed
- no oculocephalic response
- no motor response to stimulus, bilateral babinski
If there is a progressive downward lesion that hits unilaterally in the diencephalon, what is the:
- respiratory pattern
- pupil status
- oculocephalic response
- motor response
- eupneic with deep sighs or cheyne stokes
- small pupils, but react
- oculocephalic response is normal
- unilateral motor response to noxious orbital roof pressure, unilateral babinski
If there is a progressive downward lesion that is in the late third nerve stage, what is the:
- respiratory pattern
- pupil status
- oculocephalic response
- motor response
- regular sustained hyperventilation
- no direct pupil response, consensual intact
- ipsilateral eye doesnt move medially, contralateral eye retains full lateral movement
- decorticate or decerebrate
Central hyperventilation indicates a lesion where?
midbrain
