week 7 stupor and coma Flashcards
Define consciousness.
State of full awareness of the self and one’s relationship to the environment
Define delirium
- Disturbance of consciousness with reduced ability to focus, sustain, or shift attention
- a change in cognition of the development of a perpetual disturbance that is not better accounted for by a pre-existing established or evolving dementia
- the disturbance develops over a short period of time (hours to days), fluctuates over course of the day
Define obtunded.
- mild to moderate reduction in alertness, accompanied by a lesser interest in the environment
- slow psychologic responses to stimulation
- increased number of hours of sleep and is drowsy between bouts
Define stupor.
Deep sleep or unresponsiveness from which the subject can be aroused only with vigorous and continuous stimulation
Define coma
State of unresponsiveness in which the patient lies with the eyes closed and cannot be aroused to respond appropriately to stimuli even with vigorous stimulation
Define minimally conscious state.
Condition of severely impaired consciousness in which minimal but definitive behavior evidence of self or environmental awareness is demonstrated
-typically transition point
Define vegetative state.
- crude cycling of arousal states heralded by the appearance of eyes-open periods in an unresponsive patient
- still no interaction with the outside world
- persistant vegetative state=>30 days
What are the key components of the coma exam?
- level of consciousness
- pattern of breathing
- size and reactivity of pupils
- eye movements and oculovestibular responses
- skeletal motor responses
What are parts of the general examination in examining coma patients?
- examine the room for ventilator, contact/airborne/neutropenic precautions, any drips/sedatives
- signs of trauma, e.g. raccoon eyes, abrasions, fractures
- resistance to neck flexion but not lateral movement-meningitis
- check skin for petechiae, bed sores, track marks
- any restraints?
What is cheyne-stokes respiratory pattern?
- pattern of periodic breathing with phases of tachypnea and alternating regularly with apnea
- tachypnea phase longer than apnea phase
- due to lag between interaction of alveolar ventilation and brain chemoreceptor sensory responses
- causes: bilateral forebrain impairment, diffuse metabolic process
What is central hyperventilation respiratory pattern?
- sustained hyperventilation
- causes: metabolic, meningitis, SAH, brainstem tumors, salicylates
- usually bilateral hemispheres but can be seen in midbrain lesions
What is apneustic breathing?
- respiratory pause at full inspiration, 2-3 secs
- extremely rare
- injury to pontine respiratory nuclei
- most commonly from pontine stroke
What is ataxic breathing?
- irregular, gasping respiration
- damage to respiratory rhythm generator at level of the upper medulla
- usually due to strokes
What is the localization of pupillary responses?
- small, reactive: diencephalic, diffuse effects of drugs, metabolic encephalopathy
- large, fixed, hippus: pretectal
- pinpoint: pons
- bilateral, fixed: midbrain involving CN III nerves or nuclei. Large if symp in tact, midposition if sump not preserved, ciliospinal reflex to differentiate midbrain lesion and brain death
- unilateral, dilated, fixed: CN III (uncal)
- unilateral, small reactive pupil with ipsilateral ptosis: Horner’s syndrome, loss of symp/post. If loss of sweating on one half of body, lesion is between ipsilateral hypothalamus and spinal cord
What is the vestibule-ocular reflex?
- Also called oculocephalic (doll’s eyes)
- move head laterally, and eyes should move to opposite direction to preserve image in the center
- brainstem might be damaged if eyes stay mid-orbit
