Clin med 1: Stupor and Coma Flashcards
Consciousness depends on arousal of the cerebral cortex by the ____________
Brainstem Ascending Reticular Activating System (ARAS)
Impaired consciousness means involvement of what 3 things?
- Diffuse or bilateral impairment of both cerebral hemispheres, or
- Failure of brainstem ARAS, or
- BOTH
Which state of altered consciousness is represented by disorientation, stimuli misinterpretation, and hallucinations (visual)?
Delirium
Which state of altered consciousness is represented by arousal only to noxious stimuli and not enviornmental, only rudimentary awareness (i.e., purposeful motor response)?
Stupor
During a general medical exam of the skin of a patient with impaired consciousness what should be considered with dry skin?
- Hypothyroid
- Drugs (anticholinergics, TCA’s)
During a general medical exam of the skin of a patient with impaired consciousness what should be considered with acne?
Long-term antiepileptic use
Large, pressure producing supratentorial mass lesions can cause coma how?
- Dysfunction in the upper ARAS
- Downward herniation of the brain to compress the ARAS
What are the essential elements of the neurological examination for a patient with stupor?
- Pupillary responses
- Corneal reflex
- Extaocular movements
- Cough/gag reflex
- Motor responses
- Respiratory pattern
*Start at highest CN and work your way down
Why do absent or unequal pupillary responses imply a brainstem lesion?
Nuclei/tracts controlling pupils are anatomically adjacent to ARAS
What are the 3 P’s associated with pinpoint pupils?
1) Pontine lesion
2) oPiates
3) Pilocarpine
Rule of thumb for lesion location when pupils are enlarged on one side?
Parasympathetic division (usually CN III)
Rule of thumb for lesion location when pupils are enlarged bilaterally?
Bilateral CN III lesion, post-ictal, or intoxications
Rule of thumb for lesion location when pupils are constricted?
Sympathetic division (hypothalamus, carotid)
Frontal gaze centers deviate eyes where?
Pontine gaze centers deviate eyes where?
- Frontal gaze centers deviate eyes to opposite side (i.e., if right area is dysfunctional, there is no drive to the left, so eyes will be looking right)
- Pontine gaze centers deviate eyes to same side
What does conjugate vs. dysconjugate gaze imply about the brainstem?
- Conjugate implies brainstem intact
- Dysconjugate implies brainstem lesion