Coma Coma A state of unarousable psychologic unrespon A state of unarousable psychologic unrespon sive-ness in which the subjects lies with sive-ness in which the subjects lies with e e yes closed yes closed Coma vs. Consciousness Coma vs. Consciousness Consciousness: wakefulness and responsivene Consciousness: wakefulness and responsivene ss ss The severity of coma is measured by compari The severity of coma is measured by compari ng the intensity of an external stimulus an ng the intensity of an external stimulus an d the complexity and purposefulness of the d the complexity and purposefulness of the response response
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ComaComa
A state of unarousable psychologic unresponsive-A state of unarousable psychologic unresponsive-ness in which the subjects lies with ness in which the subjects lies with eyes closedeyes closed
Coma vs. ConsciousnessComa vs. Consciousness Consciousness: wakefulness and responsivenessConsciousness: wakefulness and responsiveness The severity of coma is measured by comparing tThe severity of coma is measured by comparing t
he intensity of an external stimulus and the complhe intensity of an external stimulus and the complexity and purposefulness of the responseexity and purposefulness of the response
HypersomniaHypersomnia excessive drowsiness and excessive sleepexcessive drowsiness and excessive sleep narcolepsy, hypothalamic disorders, drugsnarcolepsy, hypothalamic disorders, drugs
Akinetic mutismAkinetic mutism silent, alert, and awake appearancesilent, alert, and awake appearance regular sleep-wake cyclesregular sleep-wake cycles no evidence of response to the environment, mno evidence of response to the environment, m
ental activities, or spontaneous movementsental activities, or spontaneous movements
Locked-in syndromeLocked-in syndrome total paralysis of all somatic musculaturetotal paralysis of all somatic musculature preserved consciousness and most sensory modalitiespreserved consciousness and most sensory modalities preserved vertical eye movementspreserved vertical eye movements ventral pontine infarctventral pontine infarct
Persistent vegetative statePersistent vegetative state preserved brainstem function, including breathingpreserved brainstem function, including breathing spontaneous eye opening and regular sleep-wake cyclespontaneous eye opening and regular sleep-wake cycle
ss no recognizable cognitive functionno recognizable cognitive function
Supratentorial mass lesionsSupratentorial mass lesions causing secondary brain stem compressioncausing secondary brain stem compression
Systemic evaluation of ComaSystemic evaluation of Coma
Is there systemic illness causing brain failure?Is there systemic illness causing brain failure?
Is there evidence of diffuse or focal brain injury?Is there evidence of diffuse or focal brain injury?
Is the patient improving or deteriorating?Is the patient improving or deteriorating?
Neurological examination in ComaNeurological examination in Coma
Response to external stimulationResponse to external stimulation
Motor responseMotor response
Size and reactivity of pupilsSize and reactivity of pupils
Eye movements and ocular reflexesEye movements and ocular reflexes
Pattern of breathingPattern of breathing
Response to external stimulationResponse to external stimulation
In order of In order of verbal commandverbal command, , shoutingshouting, , shakingshaking, , and and noxious stimulationnoxious stimulation
Localizing painLocalizing pain preserved brain stem function and intact connections preserved brain stem function and intact connections
to the appropriate cerebral hemisphereto the appropriate cerebral hemisphere Eye openingEye opening
preserved function of RASpreserved function of RAS
Motor responsesMotor responses Absence of any motor responseAbsence of any motor response
severe brain stem damagesevere brain stem damage severe sedative drug ingestionsevere sedative drug ingestion
Decorticate, flexor posturing of the armsDecorticate, flexor posturing of the arms bilateral cerebral hemisphere damagebilateral cerebral hemisphere damage toxic/metabolic encephalopathytoxic/metabolic encephalopathy
Decerebrate, extensor posturing of the armsDecerebrate, extensor posturing of the arms destructive lesions of the midbrain and upper ponsdestructive lesions of the midbrain and upper pons hepatic and anoxic-ischemic encephalopathyhepatic and anoxic-ischemic encephalopathy
Midposition and fixed pupilsMidposition and fixed pupils midbrain dysfunctionmidbrain dysfunction brain deathbrain death
Unilateral dilated pupilUnilateral dilated pupil damage to IIIrd nerve from trnastentorial herniationdamage to IIIrd nerve from trnastentorial herniation
Eye movementsEye movements
Spontaneous roving, horizontal and conjugate eye Spontaneous roving, horizontal and conjugate eye movementsmovements intact brain stemintact brain stem diffuse or metabolic cortical dysfunctiondiffuse or metabolic cortical dysfunction
Doll’s eyes reflexDoll’s eyes reflex intact brainstem function with depressed cortical influintact brainstem function with depressed cortical influ
encesences normal sleep, coma, persistent vegetative statenormal sleep, coma, persistent vegetative state
Ice water caloric testIce water caloric test eyes toward the side of cold watereyes toward the side of cold water absence in brainstem lesion, inner ear disease, deep drabsence in brainstem lesion, inner ear disease, deep dr
ug coma, and anticonvulsants overdoseug coma, and anticonvulsants overdose
Periodic breathing, crescendo-decrescendoPeriodic breathing, crescendo-decrescendo The result of the loss of frontal lobe controlsThe result of the loss of frontal lobe controls Blood PCO2 drives brain stem respiratory centerBlood PCO2 drives brain stem respiratory center Posthyperventilation apneaPosthyperventilation apnea CausesCauses
Frontal lobe damage, unilateral or bilateralFrontal lobe damage, unilateral or bilateral Secondary to cardiac or respiratory failureSecondary to cardiac or respiratory failure
Central neurogenic hyperventilationCentral neurogenic hyperventilation
Sustained, rapid, deep hyperpneaSustained, rapid, deep hyperpnea NotNot secondary to hypoxemia and acidemia secondary to hypoxemia and acidemia CausesCauses
Upper brain stem lesionUpper brain stem lesion Metabolic disorders, especially the early stages of hepMetabolic disorders, especially the early stages of hep
atic coma atic coma
Apneustic breathingApneustic breathing
Prolonged inspiratory gaspProlonged inspiratory gasp Discrete lesions of the mid-to-lower ponsDiscrete lesions of the mid-to-lower pons Need early intubation and ventilationNeed early intubation and ventilation CausesCauses
pontine infarctpontine infarct hypoglycemia, anoxia, or severe meningitishypoglycemia, anoxia, or severe meningitis
Ataxic and irregular periodic breathingAtaxic and irregular periodic breathing Completely irregular patternCompletely irregular pattern Slow and progressed to apneaSlow and progressed to apnea Respiratory center - dorsomedial medullaRespiratory center - dorsomedial medulla Terminal statesTerminal states CausesCauses
posterior fossa lesionsposterior fossa lesions medullary damagemedullary damage overdoses of opiate and sedativesoverdoses of opiate and sedatives
Differential diagnosis of ComaDifferential diagnosis of Coma
Metabolic and toxic causesMetabolic and toxic causes presence of pupillary light reflexpresence of pupillary light reflex confusion and stupor precedesconfusion and stupor precedes symmetric motor signssymmetric motor signs asterixis, myoclonus, tremor, seizures (generalized)asterixis, myoclonus, tremor, seizures (generalized) central hyperventilationcentral hyperventilation
Differential diagnosis of ComaDifferential diagnosis of Coma Supratentorial mass lesionsSupratentorial mass lesions
focal neurologic singsfocal neurologic sings progresses in a rostral-caudal fasionprogresses in a rostral-caudal fasion
Subtentorial masses or destructive lesionsSubtentorial masses or destructive lesions sudden onset of comasudden onset of coma history of brain stem dysfunction (the 6 D’s)history of brain stem dysfunction (the 6 D’s) abnormal eye movementsabnormal eye movements cranial palsiescranial palsies irregular respirationirregular respiration
Diagnostic proceduresDiagnostic procedures Metabolic or toxic causesMetabolic or toxic causes
Intracranial mass lesions, head injuryIntracranial mass lesions, head injury CTCT
Acute subarachnoid or intracerebral hemorrhageAcute subarachnoid or intracerebral hemorrhage CTCT lumbar punctureslumbar punctures
Meningitis or encephalitisMeningitis or encephalitis lumbar punctureslumbar punctures
Treatment of ComaTreatment of Coma Immediate treatment, even when the diagnosis is Immediate treatment, even when the diagnosis is
uncertain, to prevent further brain damageuncertain, to prevent further brain damage Oxygenation and airway protectionOxygenation and airway protection
ET tubeET tube ventilationventilation
Blood pressures maintainBlood pressures maintain volume replacement with isotonic solutionsvolume replacement with isotonic solutions hemodynamic monitoringhemodynamic monitoring inotropic and vasopressor drugsinotropic and vasopressor drugs
Treatment of ComaTreatment of Coma
GlucoseGlucose (50 mL of 50% glucose) (50 mL of 50% glucose) ThiameThiame (100 mg, with the glucose) (100 mg, with the glucose) Seizures stopSeizures stop Intracranial hypertension lowerIntracranial hypertension lower Systemic infections controlSystemic infections control Acid-base and electrolytes imbalances correctAcid-base and electrolytes imbalances correct Hyperthermia treatHyperthermia treat
1st day: absence of pupillary responses predicts p1st day: absence of pupillary responses predicts poor outcomeoor outcome
2nd day: no patients lack corneal reflex regained 2nd day: no patients lack corneal reflex regained consciousnessconsciousness
After 3rd day: lack or purposeful motor responses After 3rd day: lack or purposeful motor responses predict poor outcomepredict poor outcome
Persistent Vegetative State (PVS)Persistent Vegetative State (PVS)
A form of eyes-open permanent unconsciousness.A form of eyes-open permanent unconsciousness.
Periods of wakefulness and physiologic Periods of wakefulness and physiologic sleep/wake cycles.sleep/wake cycles.
Unaware of self or environment.Unaware of self or environment.
Persistent Vegetative State (PVS)Persistent Vegetative State (PVS)
No voluntary action or behavior. Only primitive rNo voluntary action or behavior. Only primitive reflexes and vegetative functions.eflexes and vegetative functions.
Careful and extended clinical observation, supporCareful and extended clinical observation, supported by laboratory studies.ted by laboratory studies.
In cases of hypoxic-ischemic encephalopathy, obsIn cases of hypoxic-ischemic encephalopathy, observation period of one to three months.ervation period of one to three months.
Prolonged survival.Prolonged survival. No pain or suffering.No pain or suffering.
Neurological criteria for DeathNeurological criteria for Death
The Uniform Determination of Death Acts:The Uniform Determination of Death Acts: irreversible cessation of circulatory and respiratory irreversible cessation of circulatory and respiratory
functions, orfunctions, or irreversible cessation of all functions of the entire irreversible cessation of all functions of the entire
brain, including the brain stembrain, including the brain stem The determination of death must be made in The determination of death must be made in
accordance with accepted medical standardsaccordance with accepted medical standards
Diagnosis of Death by neurologic criteriaDiagnosis of Death by neurologic criteria
A A clinicalclinical diagnosis, with preconditions and confi diagnosis, with preconditions and confirmatory testsrmatory tests
The core of the clinical diagnosis is to establish uThe core of the clinical diagnosis is to establish unresponsiveness and brain stem areflexianresponsiveness and brain stem areflexia
The preconditionsThe preconditions the cause of coma be knownthe cause of coma be known the cause be adequate to explain the comathe cause be adequate to explain the coma