Coma Flashcards
delirium
– fluctuating confusion, inattention, misperceptions (illusions or hallucinations).
stupor
– a sleep-like state from which the patient can be aroused only by vigorous stimuli.
coma
– a sleep-like state where the patient is unresponsive to external stimuli, and there are no sleep-wake cycles. Usually lasts no more than 4 weeks. GCS 8 or less
GCS
Motor Obeys – 6 Localizes – 5 Normal flexion/withdraws– 4 Abnormal flexion (decort)– 3 Extension (decerebrate) – 2 No response – 1
Verbalization Orientated – 5 Confused – 4 Inappropriate words – 3 Incomprehensible sounds – 2 No response – 1
Eye opening Spontaneously – 4 To voice – 3 To pain – 2 No response – 1
decorticate
(flexion) upper extremity flexion with lower extremity extension (suggests lesion at hemispheres)
decerebrate
(extension) upper extremity extension with lower extremity extension (suggests lesion at upper brainstem)
Decerebrate is worse than decorticate
severity of TBI
Mild = GCS 15-13 Moderate = 12-9 Severe = 8-3
GCS definition of coma
Patients are in coma if they are unable to:
- Follow commands
- Speak any recognizable words
- Open either eye
(100% if GCS 3-7, 0% if 9-12, 50% if 8)
What happens after coma?
Death (about 50 % of trauma patients at 1 month),
Revival of consciousness, or
Vegetative state (VS), where sleep-wake cycles re-establish, but there is no sign of cognitive function.
Minimally conscious state (MCS)
determination of death
An individual who has sustained either (1) irreversible cessation of circulatory and respiratory functions, or (2) irreversible cessation of all functions of the entire brain, including the brainstem, is dead.
A determination of death must be made in accordance with accepted medical standards.
first criterion of brain death
“Unresponsiveness”
The patient is in deep coma. The GCS is 3.
second criterion of brain death
“Cerebrally modulated motor responses are absent during application of painful stimulus.”
(Spinal reflexes may be present. Seizures or flexion/extension posturing may not)
third criterion
“Brainstem reflexes are absent”
pupils, corneals, oculocephalic, oculovestibular, cough, gag, respirations
determination of brain death (ALL)
Core body temp of 32.2 C (90 F)
Toxicology tests find no explanation for low neurological state (CNS suppressing medications may be subtherapeutic)
Adequate BP and pulse (SBP 90, P >50)
No voluntary movements or response to pain (spinal reflexes are OK, e.g., DTR,. Babinski)
absence of : Pupillary light reflex Corneal reflex Oculocephalic reflex (doll’s eyes) Oculovestibular reflex (cold calorics) Cough reflex Gag reflex Respiratory effort (apnea test)
corneal reflex
Touch cornea with tissue. (CNs V and VII)
There must be no blink response in either eye.
Oculovestibular reflex (cold caloric test)
Flush each external auditory canal with 20 ml ice water x 2 and observe (CNs VIII, III, IV and VI)
There must be no eye movements
cough reflex
Suction the trachea at the carina. (CN X)
There must be no cough response.
gag reflex
Touch the oropharynx with Q-tip. (CNs IX and X)
There must be no movement of the oral structures.
Apnea test procedure
(before discontinuing the ventilator)
- 100% oxygen delivered for 10 minutes
- pCO2 around 40 mmHg on arterial blood gas
- Maintain adequate blood pressure and pulse
- Determine if pt has “tripped the vent” recently
- Disconnect vent from ET tube (begin timing)
- Deliver oxygen at 6 L/min by t-piece
- Observe and feel for respiratory effort (if breathing is observed, stop test/connect vent)
- After 8 minutes, draw blood gas and reconnect ventilator. If no respiratory effort was observed and the pCO2 is 20 or more mmHg higher than baseline, the apnea test is POSITIVE (c/w brain death)
When are confirmatory tests performed?
- BP or pulse cannot be stabilized
- Anatomy does not allow examination
- Patient is a young child (always if
vegetative state
eyes open spontaneously; sleep-wake cycles resume but there is no evidence of perception, communication, or purposeful motor activity.
(Unconscious without awareness but with wakefulness and the appearance of sleep-wake cycles )
thalamus plays a role
When due to trauma, it is considered to be permanent (
minimally conscious state
eyes open spontaneously; sleep-wake cycles resume; arousal level may be normal at times; there are reproducible, even though inconsistent, behavioral displays of perception, communication, or purposeful motor activity.
