coma Flashcards
- Define the following terms: delirium,
Delirium: Fluctuating levels of consciousness with confusion, inattention and misperceptions such as illusions or hallucinations.
- Understand the criteria for establishing brain death.
- Unresponsiveness (GCS 3)
- Cerebrally modulated motor responses are absent during application of painful stimulus.
- Brain stem reflexes are absent
Additional criteria often include: - Core Body Temperature of 32.2 degrees C
a. Avoid being fooled by very low body temperatures which can improve - Toxicology tests find no explanation for low neurological state
- Adequate BP (systolic 90) and pulse (>50)
- No voluntary movements or response to pain
a. Spinal reflexes can be intact
Other low brain activity states that are NOT coma or brain death.
Vegetative state: eyes open spontaneously; sleep-wake cycles resume but there is no evidence for perception, communication or purposeful motor activity. These states are associated with problems of the thalamus and the intralaminar nuclei within the thalamus. When due to trauma, vegetative state is considered permanent after 12 months. When due to anoxia, vegetative state is considered permanent after 3 months.
Minimally conscious state: Eyes open spontaneously, sleep-wake cycles resume, arousal levels may be normal at times, there are reproducible but inconsistent, behavioral displays of perception, communication or purposeful motor activity.
- Discuss ethical, legal, and cultural issues related to brain death and organ transplantation.
Two methods of donation:
1. Donation after brain death
2. Donation after cardiac death
Both require a declaration of death prior to organ harvesting and the surgical team harvesting the organs may not be involved with the determination of death.
In CO, if the patient lacks advance directives, there is no automatic proxy. All the interested persons must be contacted by the physician and the interested persons must choose a proxy by consensus. If there is no consensus or no interested persons, then there must be a petition to the court for a guardian.
- Describe the anatomical pathways tested with: the corneal blink reflex, cold water calorics, the cough and gag reflexes.
Pupillary Reflex: Shine light in each eye to test CNs II and III. In brain death, there is not direct or consensual constriction.
Corneal Blink reflex: CNs V and VII. Use cotton wisp or dull object to touch cornea. There cannot be a blink from either eye.
Oculopcephalic Reflex: CNs VIII, III, IV and VI. Can be done by “doll’s eyes” method: rotating head and watching for eye movements. In coma, eyes may lag, but will return to midline. In brain death, there are no movements of any kind. Can also be done by flushing external auditory canal with 20mls of ice water and observe eyes. In coma, eyes will move away from cold water but in brain death eyes will not move.
Cough Reflex: Testing CN X. Test by suction of the carina of the trachea. Looking for a cough or a bucking against the ventilator. Indicates patients initiated breath. No cough reflex in brain death.
Gag Reflex: CNs IX and X. Touch the oropharynx on each side with swab or Q-tip, look for movement of the oral structures. In brain death, there is no motor effect.
cold caloric poor cold water in ear and look for eye mvts
stupor
Stupor: A sleep like state from which the patient can be aroused, but only by vigorous stimuli.
coma
Coma: A sleep like state where the patient is unresponsive to external stimuli, there are no sleep-wake cycles. Usually lasts no more than 4 weeks and is a Glasgow Coma Scale core of 8 or less.
decerebrate posturing,
Decorticate Posturing: An involuntary flexion of the arms with lower body extension which indicates brain damage at the level of the diencephalon or cerebral hemispheres.
decorticate posturing.
Decerebrate Posturing: An involuntary extension of the arms and lower extremities which is suggestive of a lesion at the brainstem. This prognosis is worse for this than decorticate posturing.
