Approach%20to%20a%20Child%20with%20Coma

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Approach to a Child with Coma

• Prof Rashmi Kumar
• Department of Pediatrics,
• KG Medical University,
• Lucknow

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Coma Definition

• Derived from the Greek word Koma or deep sleep
• Various grades spectrum
• State of altered consciousness with reduced
  capacity for arousal and reduced responsiveness
  to visual, auditory and tactile stimulation

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• The word coma should be differentiated from
• Syncope (transient alteration of consciousness)
• Seizure

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Coma Pathophysiology

• Normal consciousness is maintained by integrity
  of certain areas of the cerebral cortex, thalamus
  and brain stem
• Altered consciousness due to
• Diffuse lesions of cerebral cortex (metabolic,
  toxic, hypoxic)
• Focal lesions of ARAS - central core of brain stem

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Coma Pathophysiology

• Diffuse insult to both cerebral hemispheres
• (metabolic/toxic/hypoxic/ischemic)
• or
• focal lesion affecting ascending reticular
  activating system (ARAS) located in upper pons,
  midbrain diencephalon. Affected by
  compression (herniation)
• Lesion in one cerebral hemisphere will not
  produce coma
• ?ICT generalised ischemia (CPPMAP-ICT)
• focal ARAS damage by
  herniation

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Coma Pathophysiology
Diffuse bilateral cerebral lesion
Mass lesion compressing ARAS
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Coma Etiology

• CNS Causes Structural
• CNS infections
• Mass lesions ? CSF obstruction ? volume
• Trauma
• Vascular
• CNS Causes Functional
• Seizures
• Hypoxic - ischemic injury

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Coma EtiologyExtracranial causes Metabolic

• Systemic shock
• hypo/ hypernatremia
• hypoglycemia
• diabetic coma
• hepatic
• uremic

• hypoxia
• Reyes
• Respiratory failure
• Acidosis/ alkalosis
• Hyperosmolality
• Inherited metabolic disorders

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Coma EtiologyExtracranial causes Drugs

• Iron
• Salicylates
• aceraminophen
• Metals

• Barbiturates
• benzodiazepines
• opioids
• tricyclics
• antihistamines

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Coma Etiology

• Extracranial causes
• Toxic
• Lead
• gram negative endotoxemia
• Shigella
• CO poisoning
• pesticides
• alcohol/ ethylene glycol

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Coma Etiology

• Extracranial causes
• Endocrine
• hypothyroidism
• diabetic
• Miscellaneous
• hypertensive encephalopathy
• heat stroke
• hypothermia
• Psychogenic

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Coma Immediate Management

• Is resuscitation required?
• A airway ? prevent tongue falling back, suction
• B breathing?respiratory support, oxygen
• C- circulation?iv fluids, monitor BP,
  vasopressors
• If any evidence of poisoning ? GL

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Coma Quick History Examn

• Circumstances?
• Duration onset? Acute in CNS infection,
  trauma, seizure, poisoning, metabolic, vascular
• H/o poisoning?
• H/o trauma?
• H/o fever?
• H/o seizure?
• Past medical history
• H/o seizures in the past?
• H/o known endocrine disorder?
• H/o headache/vomiting/visual symptoms?

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Coma Quick History Examn

• Vitals
• Fever
• BP
• S/o shock
• S/o ? ICP? bradycardia, hypertension
• Respiration ? rapid in acidosis CNS lesions
  also
• General Physical
• Evidence of trauma, injury, tongue bite
• Jaundice
• Breath - for odor of ketones, fetor hepaticus etc
• Skin peticheae, exanthem
• Dry, flushed skin in belladonna poisoning
• Moist skin with ?salivation in organophosphorus
  poisoning
• Complete systemic exam

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Coma Neurological Examn

• Painful stimuli- strong pinch, pressure on nail
  bed, pressure on globe
• Glasgow Coma Scale
• Best Motor Best Verbal
  Eye opening
• 1. none none
  none
• 2. extension to incomprehensible
  to pain
• pain sounds
• 3. flexion to inappropriate
  to call
• pain words
• 4. withdraws confused speech
  spontaneous
• 5. localises well oriented
• 6. Moves on
• command

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Coma Neurological Examn

• Modified Coma Scale for children lt 2 yrs
• Best Motor Best Verbal Eye opening
• 1. none none
  none
• 2. extension to moaning to to
  pain
• pain pain
• 3. flexion to crying to
  to call
• pain pain
• 4. withdraws irritable cry
  spontaneous
• 5. localises coos, babbles
• 6. Moves on
• command

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Coma Neurological Examn

• Meningeal signs
• Tone/posturing
• Decerebrate- lesion in upper pons
• Decorticate- b/l cortical lesion with
  preservation of brain stem function
• Flaccidity when all cortical brain stem
  function till pontomedullary junction are lost
• Fundus
• Pupils
• Pinpoint in pontine lesions/morphine poisoning
• B/l fixed dilated in terminal state, severe
  ischemic damage, atropine/belladonna poisoning
• U/l unreactive pupil ? transtentorial
  herniation
• Pupils generally small, equal reactive in
  toxic/metabolic causes

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Coma Neurological Examn

• Cranial nerves
• 6th nerve palsy false localizing sign
• u/l 3rd impending herniation
• Deficits suggest lesion in brain
• S/o ?ICP
• hypertension/bradycardia/abnormal breathing
  (Cheyne Stokes, hyperventilation, apneustic,
  ataxic)
• papilledema
• posturing
• cranial nerve palsies
• Brain stem reflexes
• Dolls eye response
• Oculovestibular reflex
• Corneal reflex

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Structural vs functional coma

• Meningeal signs
• Focal deficits
• Brain stem reflexes lost
• Pupils unequal or fixed dilated

• Absent
• Absent
• Present
• Semidilated and reactive

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Coma Investigations

• Counts
• Blood glucose, urea, electrolytes, acid base
• Ammonia, liver function, lactate
• Toxicology
• Lumbar puncture CI if ?ICP. Abnormal in CNS
  infections
• Cultures
• EEG usually non specific
• Imaging r/o mass lesion

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Coma Treatment

• Treat the cause
• Supportive care antipyretics, anticonvulsants
• Management of ?ICP
• Mannitol 0.25 1 gm/kg of 20 solution (1.25
  5 ml/kg) bolus iv
• Frusemide
• Diamox, glycerine
• Steroids esp vasogenic edema
• Hyperventilation ? lowers CBV??CPP
• Maintain PCO2 between 25 30 mm Hg
• Nursing care
• Position
• Nutrition
• Care of eyes
• Care of skin
• Chest physiotherapy
• Care of bowel bladder
• Physiotherapy

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Persistent vegetative state

• patients after recovery from coma return to a
  wakeful state without cognition/ awareness of
  environment
• Children who remain in this state for gt 3 months
  do not regain functional skills
• Causes anoxia/ischemia/metabolic/encephalitic
  coma/head trauma
• Survival indefinite with good nursing care

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Coma Diagnosis of Brain Death

• Importance
• (American Academy of Neurology, 1995)
• Prerequisites
• Cessation of all brain function
• Proximate cause of brain death is known
• Condition is irreversible
• Cardinal features
• Coma
• Absent brain stem reflexes
• Pupillary light reflex
• Corneal reflex
• Oculocephalic
• Oculovestibular
• Oropharyngeal
• Apnea
• Confirmatory tests (optional)
• Cerebral angiography
• Electroencephalography
• Radioisotope cerebral blood flow study

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Apnea Test

• Prerequisites- Core temperature gt 36.5O C (97o
  F).- Systolic blood pressure gt 90 mm Hg (Adults
  only).- Euvolemia (or positive fluid balance in
  the previous 6 hours).- Normal PCO2 (or arterial
  PCO2 gt 40 mm Hg). - Normal PO2 (or
  preoxygenation to obtain arterial PO2 gt 200 mm
  Hg).
• Connect a pulse oximeter. Disconnect the
  ventilator or place the patient on CPAP at an
  appropriate level or place a cannula at the level
  of the carina and administer 100 O2
  endotracheally at 8L per minute.
• Look closely for respiratory movements abdominal
  or chest excursions that produce adequate tidal
  volumes).- Measure arterial PO2 , PCO2 , and pH
  after approximately 8 minutes (10 minutes for
  children). Resume mechanical ventilation.
• Absence of spontaneous respiratory effort with
  PCO2 20 mm Hg gt baseline (PCO2 gt 60 mm Hg)
  confirms apnea and supports the diagnosis of
  death. If respiratory efforts are present, the
  test is inconsistent with brain death and should
  be repeated. For children, if the rise in PCO2
  fails to reach 60 mm Hg, perform the test again
  for a duration of 15 minutes.- If the blood
  pressure becomes unstable or significant oxygen
  desaturation and cardiac arrhythmias are present
  during testing, resume ventilation. Immediately
  draw an arterial blood sample. If PCO2 gt 60 mm Hg
  or the increase is 20 mm Hg gt baseline normalized
  PCO2, the apnea test is consistent with brain
  death. If not, the result is indeterminate. A
  confirmatory test may be useful.

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• A. History determine the cause of coma to
  eliminate remediable or reversible conditions
• B. Physical examination criteria
• 1. Coma and apnea
• 2. Absence of brain stem function
• (a) Mid-position or fully dilated pupils
• (b) Absence of spontaneous oculocephalic (doll's
  eye) and caloric-induced eye movements
• (c) Absence of movement of bulbar musculature,
  corneal, gag, cough, sucking and rooting reflexes
• (d) Absence of respiratory effort with
  standardized testing for apnea
• 3. Patient must not be hypothermic or hypotensive
• 4. Flaccid tone and absence of spontaneous or
  induced movements excluding activity mediated at
  spinal cord level
• 5. Examination should remain consistent for brain
  death throughout the predetermined period of
  observation

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• Observation period according to age
• 7 days to 2 months Two examination and EEGs 48
  hours apart
• 2 months to 1 year Two examination and EEGs 24
  hours apart or one examination and an initial EEG
  showing ECS combined with a radionuclide
  angiogram showing no CBF.
• More than 1 year Two examinations 12 to 24 hours
  apart EEG and isotope angiography are optional
• (No criteria for neonates lt 7days of age)

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MCQ

• 1.  Cerebral Perfusion Pressure equals
• a)      Mean arterial pressure intracranial
  pressure
• b)      Mean arterial pressure - intracranial
  pressure
• c)       Intracranial pressure Mean arterial
  pressure
• d)      None of the above

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• 2. The following is true about Glasgow Coma
  Scale
• a)      The highest score is 10
• b)      Lowest score is 3
• c)       There are 5 possible scores for Best
  Motor Response
• d)      Lowest score is 0

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• Unilateral unresponsive pupil is found in
• a)      Morphine poisoning
• b)      Impending trantentorial herniation
• c)       Belladona poisoning
• d)      Brain death

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• A 7 year old child is brought to the emergency
  in coma. On deep painful stimulus there is no
  verbal response, no eye opening and slight
  extension of limbs. What is his Glasgow Coma
  Score?
• a)      7
• b)      9
• c)      5
• d)      4

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• Signs of raised intracranial tension include all
  except
• a)      Hypertension
• b)      Shallow breathing
• c)       Bradycardia
• d)      Papilledema

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• Prerequisites for diagnosis of brain death
  include all except
• a)      Cessation of all brain function
• b)      Flat EEG
• c)       Proximate cause of coma is known
• d)      Condition is irreversible

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