Etiologies of coma

Trauma

  • Parenchymal injury
  • Intracranial hemorrhage (epidural, SDH, SAH)
  • Diffuse Axonal Injury

Nontraumatic

  • Toxic/metabolic
  • HIE (shock, cardiopulm arrest, near-drowning)
  • Toxins
    • Medications: narcotics, sedatives, antiepileptics, antidepressants, analgesics, aspirin
    • Environmental toxins: organophosphates, heavymetals, cyanide, mushroom poisoning
    • Illicit substances 
  • Systemic metabolic disorders
    • Substrate deficiencies (hypoglycemia, cofactorssuch as thiamine, niacin, pyridoxine)
    • Electrolyte and acid-base imbalances
    • DKA
    • Thyroid/adrenal/other endocrine disorders
    • Uremic or hepatic coma
    • Reye syndrome
    • Inborn errors of metabolism (urea cycle defect,amino acidopathies, mitochondrial disorders)   
  • Infections (Meningitis, encephalitis)
  • Inflammatory (Sarcoidosis, Lupus cerebritis)
  • Mass lesions (neoplasms, abscess, hydrocephalus)
  • Paroxysmal neurologic disorders (seizures, migraines)
  • Vascular
    • Intracranial hemorrhage
    • Arterial infarcts
    • Venous sinus thromboses
    • Vasculitis 

Initial evaluation of coma

  • ABC’s: assessment and stabilization
    • Ensure adequate ventilation & oxygenation
    • BP monitoring  
  • Draw labs: Glucose, lytes, ammonia, blood gas, LFTs, BUN/Cr, CBC, lactate, pyruvate, and toxicology screen
  • Head CT
  • Neuro assessment
    • GCS score
    • Assess for raised intracranial pressure / herniation
    • Assess for focal neurologic disease
    • Assess for history or signs of seizures 
  • If concern for infection, give broad spectrum antibiotics
    • Consider LP prior to abx if no delay in doing procedure 
  • Consider antidotes for specific toxic exposures
  • Identify and treat critical elevations in intracranial pressure
    • Neutral head position, HOB 30 degrees, sedation
    • Hyperosmolar therapy (Mannitol, 3% NaCl, 7% NaCl)
    • Hyperventilation as temporary measure
    • Consider intracranial monitoring
    • Consider neurosurgical intervention 
  • Seizure prophylaxis / treatment
  • Consider EEG
  • Detailed history and physical
  • MRI if concerns for stroke

Glascow coma scale

Eye openingVerbal ResponseMotor Response

Eye opening Verbal Response Motor Response
Spontaneous 4 
To command 3
To pain 2
None 1
Oriented 5
Confused 4
Disoriented/ 
inappropriate words 3
Incomprehensible sounds 2
None 1
Obeys commands 6
Localizes pain 5  
Withdraws 4
Abn flexion to pain 3
Abn extension 2
None 1

*Adapted from Roger’s Handbook of Pediatric Intensive Care, 4th Edition