Altered Mental Consciousness _AMC__ Coma

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					Altered Mental Consciousness
(AMC)& Coma

      CNS Module-Week 4
    Definition of consciousness

n   Consciousness is a state in which an
    individual is awake, alerted to the surrounding
    environment. This requires certain level of
    concentration and attention.
Anatomic structures are required to
maintain consciousness

n   For normal consciousness, active
    function of 2 main parts of the nervous
    system is required
    ¡   Reticular formation in the brainstem,
        which is responsible for the state of
    ¡   Cerebral cortex is responsible for the
        state of awareness.
    Review the definitions of altered

n   Drowsy & Lethargy: are very subjective terms that
    have no strict definition but generally they stimulate light
    sleep and are characterized by easy arousal and
    persistence of alertness for brief periods.
n   Obtunded: is a condition in which a patient doesn’t
    respond to sound, clapping, & shaking but responds to
    vigorous painful stimulus (supra-orbital pressure, nail
    bed pressure, or squeezing the nipple). Stupor is very
    similar to obtunded.
n   Delirium: Disturbance in consciousness, with a reduced
    ability to focus, to sustain focus or to shift attention
        Review the definitions of altered
n   Dementia: Memory impairment and at least one of the
    ¡   Aphasia: impairment in understanding and/or formulating complex,
        meaningful elements of language.
    ¡   Apraxa: is a motor disorder in which volitional or voluntary movement
        is impaired without muscle weakness
    ¡   Agnosia: is a general term for a loss of ability to recognize objects,
        people, sounds, shapes, or smells .
n   Coma: a condition in which the patients’ eyes are closed,
    there is no spontaneous motor activity and no response to
    deep painful stimulation.
n   Vegetative state: a state of which the patient is awake but is
    not aware of the outer environment therefore doesn’t respond
    to stimuli. This happens when the reticulor formation is intact
    but the cerebral cortex is not functioningIf it is persists to
    more that 6 months it is considered chronic vegetative state.
    We have to consider other conditions that
    could mimic vegetative state such as
•   Lock-in syndrome: is a pseudo-coma state in which an awake
    patient has no means of producing speech or volitional limb, face
    and pharyngeal movements in order to indicate that he/she is
    awake. But vertical eye movements and lid elevation remains
    unimpaired. It is usually caused by damage to the ventral pons,
    which transect all descending coticospinal and corticobulbor
•   Cerebral palsy: group of chronic, non-hereditary condition of
    varying severity that are believed to be the result of faulty
    development of, or damage to, the motor areas in the brain, which
    then causes a disruption in the brain's ability to control muscular
    movement and posture. But it doesn’t affect mental status
•   Brain Death: is defined as irreversible loss of brain function,
    including the brainstem. The three cardinal signs for brain death
    are: Coma (unresponsiveness), absence of brainstem reflexes
    (papillary reflex, oculocephalic reflex, conrneal reflex, gag reflex)
    and apnea.
Assessment of Coma and altered level
of consciousness

n   Neurological exams that will help
    localize the lesion (Focal vs Non focal)
    ¡   pupillary exam
    ¡   respiratory patterns
    ¡   posture and spontaneous movements
    ¡   cranial nerve exam
    ¡   extraocular movements
    ¡   Glasgow Coma scale
Glasgow coma scale

n    Physicians usually use the Glasgow coma scale to
     Asses the level of consciousness, which evaluates
     eye opening (E), Verbal response (V) and motor
     response (M)
                          Glasgow Coma Score

                                                    Motor Response
    Eye Opening (E)      Verbal Response (V)

    4=Spontaneous     5=Normal conversation        6=Normal
    3=To voice        4=Disoriented conversation   5=Localizes to pain
    2=To pain         3=Words, but not coherent    4=Withdraws to pain
    1=None            2=No words, only sounds      3=Decorticate
                      1=None                       2=Decerebrate
              Approach to patient with coma or altered metal

Signs of focal lesion        Signs of focal and non-            Signs of non-focal lesion
                             focal lesion
Imaging is the                                                EEG is the diagnostic test
diagnostic test         EEG & imaging should be

Possible causes:            Possible causes:
• Infection                 • meningitis             Possible cause is encephalopathy (The
• Hemorrhage                •encephalitis            brain is pathic/sick)

• Tumors
• Arterial-venous                     Hypoxic/Anoxic      Toxic/metabolic   Post Ictal causes:
malformation                          causes:             causes:                   •Seizures
                                      •Cardiac arrest     •Cardiac arrest
                                      •Drowning           •Drowning
                                      •Suffocating        •Suffocating
Immediate interventions for patient
with Altered consciousness

n   ABC’s
n   intravenous access, oxygen therapy
n   glucose / thiamine
n   cardiac monitoring with pulse oximetry
n   cervical spine precautions
n   Naloxone to reverse the action of
    opioid overdose

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