Coma Flashcards
COMA
practice pattern
Practice Pattern 5I: Impaired arousal associated with coma, near coma, or vegetative state
When working with them, assume that they know everything that is being said around them
They can undertand but couldn’t respond
Don’t talk about how sad the situation is
COMA
1) what is it
2) what must be activated to maintain consciousness
3) what regulates alertness and consciousness
1) The inability to respond purposely or become consciously aroused by external or internal stimuli (Upward facilitation to “arouse” the cerebral cortex )
2) The cerebral cortex must be activated to reach and maintain conscious arousal
(Could be high levels of alcohol, meds)
3) Alertness and consciousness are regulated by the RAS in the brainstem
- –Has to be bilateral involvement for coma to occur
The Reticular Activating System (RAS)
AROUSAL
network of cells in brainstem (with projections to thalamus, hypothalamus, and cortex)
[a set of connected nuclei in the brains responsible for regulating wakefulness and sleep-wake transitions.]
can be activated by various sensory inputs
A feedback mechanism between the RAS and the cerebral cortex maintains consciousness
Bilateral damage to the ascending RAS or brainstem will result in some level of coma
**awareness is mediated by the cerebral cortex
Define Coma (5)
- UNRESPONSIVE
- CANNOT OBEY COMMANDS
- CANNOT RESPOND VERBALLY
- CANNOT OPEN EYES AND VISUALLY TRACK
- LACK OF SLEEP-WAKE CYCLES
Associated Levels of Severe TBI
1) Minimally Conscious State (light coma) – may present with reflex, primitive or disorganized responses to stimuli
2) Deep Coma – no response to painful or any stimuli
• Less descriptive terms:
3) Lethargic – drowsiness, easily aroused with light stimuli
4) Stupor – arousal only with persistent or vigorous stimuli, and arousal is incomplete
Minimally Conscious State
(light coma) – may present with reflex, primitive or disorganized responses to stimuli
o May be inconsistent but there are true responses
o Communicate with family members and see if they get an responses
Deep Coma
no response to painful or any stimuli
ie nail bed pressure
Even a reflexive response is better than no response
Lethargic
drowsiness, easily aroused with light stimuli
can be awakened
Stupor
arousal only with persistent or vigorous stimuli, and arousal is incompete
Vegetative state: (3)
- State of arousal without behavioral evidence of awareness or ability to interact with external environment
(responses but not associated with stimuli) - Rudimentary and apparent sleep-wake cycles
- May have spontaneous eye opening, but NO real visual tracking or purposeful limb movements
Minimally Conscious State
what can they do (4)
- Minimal but some purposeful AWARENESS
- GESTURE or VERBAL responses, even if not correct
- VERBALIZATION of any words, even if not correct
- -mumbling – better than no response, anything you can classify as a response - MOVEMENT or BEHAVIORS that are environmentally TRIGGERED, NOT REFLEXIVE
Locked-In Syndrome
what it is
cause
what cant they do
what can they do
NOT COMA
1) Patient appears to be in a coma, but has all HIGHER CORTICAL FUNCTION INTACT
2) Extensive LESIONS in corticobulbar and corticospinal tracts,
but higher Central Nervous System function intact
3) Cannot speak, move or breathe
***Only response you may see is controlled blinking. Cranial nerve response. NOT COMA.
Coma
1) eye opening
2) spontaneous movement
3) response to pain
4) visual response
5) affective response
6) commands
7) verbalizations
1) NONE eye opening
2) NONE spontaneous movement
3) posturing/NONE response to pain
4) NONE visual response
5) NONE affective response
6) NONE commands
7) NONE verbalizations
Vegetative
1) eye opening
2) spontaneous movement
3) response to pain
4) visual response
5) affective response
6) commands
7) verbalizations
1) eye opening: SPONTANEOUS
2) spontaneous movement: REFLEXIVE
3) response to pain: posturing/WITHDRAWAL
4) visual response:
5) affective response: random
6) commands: none
7) verbalizations: random
Minimally conscious
1) eye opening
2) spontaneous movement
3) response to pain
4) visual response
5) affective response
6) commands
7) verbalizations
1) eye opening
2) spontaneous movement
3) response to pain
4) visual response
5) affective response
6) commands
7) verbalizations
Causes of Coma
1) Falls or direct trauma
o Children
o Stairs
o Falling backwards is more of a risk
2) Motor vehicle accident
3) Motorcycle and bicycle
4) Stroke
o Especially hemorrhagic
5) Carbon monoxide poisoning
6) Near drowning
o Winter is the best time to have a near drowning experience because of the decreased brain metabolism due to the cold
7) Toxicity – alcohol, meds
8) Blast injuries
o Veterans
Glasgow Coma Scale
Eye Opening (1-4)
Motor Response (1-6)
Verbal Response (1-5)
E + M + V =
best possible of 15 / worst possible of 3
Glasgow Coma Scale
Eye opening response
4: spontaneous
3: to speech/call
2: to pain
1: none
Glasgow Coma Scale
Motor response
6: obey command
5: localize pain
4: normal flexion withdrawel
3: abnormal flexion: DECORTICATE
2: extension: DECEREBRATE
1: None: FLACCID
Glasgow Coma Scale
Verbal Response
5: oriented
4: confused conversation
3: inappropriate words
2: incomprehensible sounds
1: none
Glasgow Coma Scale Scores
E + M + V =
best possible of 15 / worst possible of 3
DECORTICATE
decorticate posturing
abnormal flexion
motor response of 3
DECEREBRATE
decerebrate posturing
extension of all 4 limbs
motor response of 2 (worse than decorticate)
Significance of Score on Admission and Outcome
COMA
the higher the glasgow coma score, the better the outcome for the patient in terms of disability/vegetative state/death
o CHART Significant of Score on Admission and Outcome page 110
Cant predict if they will come out of it or when
Look at the highest score, total from all 3
As the numbers are going up, coming out of coma (essentially)
Pupillary Response to light
1) Optic pathways to optic tract, midbrain and parasympathetic fibers to CN III.
** Intact responses are positive signs for reversible coma
Oculocephalic
Oculocephalic – (doll’s head): eyes should move in opposite direction to rapid passive head rotation
for normal response:PONS and MIDBRAIN must be intact (and brainstem)
TESTING:
move the head, do eyes move in the opposite direction or stay in the middle of the orbit or
• Eyes should move in opposite direction to rapid passive head rotation
• Non healthy patient – eyes stay fixed in the center
• Pons and midbrain must be intact for normal response
Oculovestibular Response
- procedure
- results expected
- interpretation of results
COWS
1) Cooling air indirectly stimulates the reticular formation –>
2) slow, tonic conjugates deviation of the eyes toward the irrigated side
FOLLOWED BY RAPID NYSTAGMUS TO MIDLINE
cool the semicircular canals to get the perilymph to move to get a tonic deviation to the side–brainstem intact
3) Interpretation of Response:
- Awake or light coma patient: rapid nystagmus away from stimulated ear (CNS intact)
- Unconscious patient: no return nystagmus (pons, midbrain intact)
- PONS, MIDBRAIN LESION: no response to testing = deep coma
Occulovestibular Testing
awake/light coma
unconscious
deep coma
Occulovestibular Testing
Interpretation of Response:
- Awake or light coma patient: rapid nystagmus away from stimulated ear (CNS intact)
- Unconscious patient: no return nystagmus (pons, midbrain intact)
o PONS, MIDBRAIN LESION: no response to testing = deep coma
Motor Testing
IN COMA
1) Assess quality of each response!
o Blink your eyes
o Look to the right and left
o Show me two fingers – one UE or bilateral?
o Wiggle your toes – one LE or bilateral?
• Check all 4’s to see if it s a hemi problem
• Dr’s are looking at the big picture, do tests to determine specific deficits
o IF no response, use noxious stimuli
CROSSING MIDLINE TO REMOVE A NOXIOUS STIMULI IS PURPOSEFUL AND BETTER COMPARED TO A WITHDRAWAL RESPONSE*
Sensory Testing
IN COMA
–when can it be performed
–what is it important to assess (3)
can only be performed if patient can respond to cues
important to assess the
- parietal lobe
- spinal cord,
- PNS function or injury
Factors Affecting Outcome in Coma (4)
1) SEVERITY OF INITIAL BRAIN INJURY–are structures intact to maintain life?
- —If they survive the first 24 hours, it means they did not have enough brain damage to kill them, medical management should be able to keep them alive
2) HYPOXEMIA – inadequate oxygen saturation
3) ARTERIAL HYPOTENSION
4) INTRACRANIAL PRESSURE (ICP) – would result in brain ischemia
—Tested with device put into the skull
(Working with someone with this in place – see if anything you do with them increases the pressure, if goes up – may be in response to them being handled and not the actual action)
5) Cellular responses secondary to injury
- –ie reduce swelling to prevent secondary breakdown