Term
| gradation of consciousness |
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Definition
| consciousness > delirium > obtundation > stupor > minimally conscious state > vegetative state > coma |
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Term
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Definition
| awareness of self and the environment, with the ability to react to internal and external stimuli |
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Term
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Definition
| an acute, transient, fluctuating confusional state characterized by impairment in maintaining and shifting attenting |
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Term
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Definition
a condition of mild to moderate reduction of consciousness in which subjects appear to be drowsy or asleep, with reduced interest in the environment
they can be roused with verbal or painful stimuli, tending to slip back onto their previous state when stimulation stops |
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Term
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Definition
| a state of unresponsiveness resembling deep sleep, from which subjects can be roused only by vigorous and repeated stimulation |
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Term
| minimally conscious state |
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Definition
a condition of severely altered consciousness with minimal but definite behavioral evidence of awareness of self or environment
(looks like a vegetative state, but can sometimes get a meaningful response to a meaningful stimulus) |
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Term
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Definition
a condition characterized by the complete absence of behavioral evidence for awareness of self or environment, but with the preserved capacity for spontaneous or stimulus-induced arousal, including a sleep-wake cycle
eyes are often open
no meaningful responses to environment |
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Term
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Definition
| a state in which subjects lie with eyes closed and demonstrate no conscious responses to external stimuli, even after vigorous attempts to rouse them |
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Term
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Definition
any state of altered level of consciousness or of clouded sensorium
ALL previous conditions are forms of encephalopathy |
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Term
| general approach to acute FOCAL mental status changes |
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Definition
| should be evaluated in the same way as any acute focal process - most likely TIA/stroke or trauma |
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Term
| general approach to acute DIFFUSE mental status changes |
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Definition
evaluated in a standard fashion regardless of patient's status (confused, delirious, stuporous, comatose, etc)
1)ABC's
2)ox, gluc, nalox
3)doll's eye
4)electrolytes
5)everything else |
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Term
| causes of acute diffuse mental status changes |
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Definition
**toxic/metabolic**
hypoperfusion
increased ICP
diffuse inflammation
seizures
any of the above can lead to ARAS damage |
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Term
| differential diagnosis of diffuse acute mental status change |
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Definition
| structural damage to brainstem, thalamus, bilateral cerebral cortex |
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Term
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Definition
most significant
pretty much anything can lead to change in acute metal status
major players: sodium, glucose |
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Term
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Definition
HYTPOTENSIVE EVENT - any acute decrease in BP, loss of blood flow to brain (i.e. cardiac arrest)
hyperviscosity, vasculitis, less common |
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Term
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Definition
obstructive hydrocephalus
diffuse edema in the brain |
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Term
| posterior reversible encephalopathy syndrome |
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Definition
diffuse edema through the brain as a result of 2ndary:
-HTN crisis
-some drugs
-eclampsia
all have similar pathophysiology and radiographic features similar |
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Term
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Definition
encephalitis
meningitis
subarachnoid hemorrhage
meningeal metastasis |
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Term
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Definition
alteration in level of alertness
-complex partial seizures
-generalized seizure
-post ictal state |
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Term
| clinical approach to acute mental status changes |
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Definition
stereotyped approach; idea of triage
1. ABC's
2. oxygen, glucose, naloxone
3. pupils, doll's eyes, motor asymmetry
4. other electrolytes, renal, hepatic, temperature
5. everything else |
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Term
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Definition
you won't be able to fix anything else until you ensure that the patient has adequate:
AIRWAY
BREATHING
CIRCULATION |
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Term
2. Oxygen, Glucose, Naloxone
why? |
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Definition
simultaneous diagnostic/therapeutic maneuver
kypoxia and hypoglycemia can both be fatal or ave serious permanent sequelae if not treated urgently
prompt treatment may result in complete recovery
narcotic overdose is less urgent, but responds promptly to naloxone, eliminating the need for further evaluation |
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Term
2. Oxygen, Glucose, Naloxone
how? |
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Definition
oxy: pulse ox or ABG; 100%O2 by mack
glucose: finger stick; 1 amp D50
naloxone: give! |
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Term
| 3. pupils, doll's eyes, motor asymmetry |
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Definition
important to assess for a potential mass lesion that could be affecting the ARAS or both hemispheres
check for herniations |
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Term
| uncal herniation manifestations |
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Definition
CN III exits in an area that is easily compressible from an uncal herniation
parasympathetics travel with CN III so compression results in unopposed sympathetic activation = "blown" pupil |
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Term
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Definition
tests the vestibulo-ocular reflex
+ test: eyes remain fixed on the same point in space during head rotation
- test: patient's eyes rotate with the head, eyes remain fixed relative to the head |
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Term
| significance of absent doll's eyes reflex |
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Definition
in a comatose patient, absence of this reflex indicated dysfunction within the vestibulo-ocular reflex pathway: afferent limb (vestibular nerve), efferent limb (CN III, VI + mm), pathways connecting them to pons and medulla
absent response + intact pupillary reflex = NOT HERNIATION |
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Term
| transtentorial herniation |
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Definition
early in herniation, CN III compression eliminates pupillary constriction = pupil is dilated and unreactive to light
further progression of herniation knocks out CN IV, VI, VIII = absent doll's eyes
if doll's eyes absent but pupils reactive, NOT this herniation |
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Term
| assessing motor asymmetry |
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Definition
deliver noxious stimulus to each side
does response differ to stimuli on left and right?
do left and right side move equally to a given stimulus? |
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Term
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Definition
in response to noxious stimulus:
-flexion and adduction of upper extremities
-extension of lower extremities
(better prognosis) |
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Term
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Definition
in response to noxious stimulus:
-pronation, adduction, proximal extension of upper extremities with wrist flexion
-extension of lower extremities |
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Term
| 4. other electrolytes, renal, hepatic, temperature |
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Definition
(if no idea what's going on yet, all bets are off)
after correcting ABC's, checking O2/gluc, pupil/motor, the blood tests that were sent during #2 should be back
look for anything suggesting metaboilc/toxic issues
in temp <34C or >39-40C it should be evaluated and corrected |
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Term
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Definition
if cause of mental status change not yet established, consider: other toxins, subtle seizures or post-ictal state, inflammatory disease
work-up may include: head CT/MRI, EEF, LP, pan-culture |
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Term
| management of post-hypoxic coma |
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Definition
aggressive care for 48-72 hours (unless non-neurologic condition is hopeless)
at 72 hours:
-if NO purposeful withdrawal to pain, meaningful recovery LOW
-if purposeful withdrawal to pain and patient looks to an auditory stimulus, likelihood of meaningful recovery is GOOD |
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Term
| recovery in persistent vegetative state / minimally conscious state |
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Definition
some patients recover from these conditions, most don't
management can pose ethical dilemmas, especially if patient did not issue clear advance directives |
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Term
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Definition
complete loss of meaningful brain function
-cortical AND brainstem
spinal reflexes may still be present
brain death = death |
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Term
| when is brain death determination necessary? |
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Definition
only in 2 situations:
-organ donation
-insistence on continued treatment by some involved in patient's care |
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