1. Approach to a Child with Coma
Prof Rashmi Kumar
Department of Pediatrics,
KG Medical University,
Lucknow

2. 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

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

4. 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

5. 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 (CPP=MAP-ICT)
focal ARAS damage by herniation

6. Coma: Pathophysiology
Diffuse bilateral cerebral lesion
Mass lesion compressing ARAS

7. Coma: Etiology CNS Causes: Structural CNS infections
Mass lesions  CSF obstruction +  volume
Trauma
Vascular
CNS Causes: Functional
Seizures
Hypoxic - ischemic injury

8. Coma: Etiology Extracranial causes Metabolic
Systemic shock
hypo/ hypernatremia
hypoglycemia
diabetic coma
hepatic
uremic
hypoxia
Reye’s
Respiratory failure
Acidosis/ alkalosis
Hyperosmolality
Inherited metabolic disorders

9. Coma: Etiology Extracranial causes Drugs
Iron
Salicylates
aceraminophen
Metals
Barbiturates
benzodiazepines
opioids
tricyclics
antihistamines

10. Coma: Etiology Extracranial causes Toxic Lead
gram negative endotoxemia
Shigella
CO poisoning
pesticides
alcohol/ ethylene glycol

11. Coma: Etiology Extracranial causes Endocrine Miscellaneous Psychogenic
hypothyroidism
diabetic
Miscellaneous
hypertensive encephalopathy
heat stroke
hypothermia
Psychogenic

12. 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

13. 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?

14. 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

15. 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

16. Coma : Neurological Examn
Modified Coma Scale for children < 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

17. 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

18. 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:
Doll’s eye response
Oculovestibular reflex
Corneal reflex

19. Structural vs functional coma
Meningeal signs
Focal deficits
Brain stem reflexes lost
Pupils unequal or fixed dilated
Absent
Present
Semidilated and reactive

20. 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

21. 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

22. 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 > 3 months do not regain functional skills
Causes – anoxia/ischemia/metabolic/encephalitic coma/head trauma
Survival indefinite with good nursing care

23. 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
Transcranial Doppler ultrasonography
2 examinations – interval depends
One/two physicians

24. Apnea Test
Prerequisites:- Core temperature > 36.5O C (97o F). - Systolic blood pressure > 90 mm Hg (Adults only). - Euvolemia (or positive fluid balance in the previous 6 hours). - Normal PCO2 (or arterial PCO2 > 40 mm Hg). - Normal PO2 (or preoxygenation to obtain arterial PO2 > 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 > baseline (PCO2 > 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 > 60 mm Hg or the increase is 20 mm Hg > baseline normalized PCO2, the apnea test is consistent with brain death. If not, the result is indeterminate. A confirmatory test may be useful.

25. 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

26. 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 < 7days of age)

27. 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

28. 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

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

30. A 7 year old child is brought to the emergency in coma
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

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

32. 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

33. THANK YOU