Coma + altered consciousness

Nota:

• requires: -intact ascending reticular activating system (loc in brainstem + responsible for arousal) -normal funct of cerebral cortex, thalamus and their connxns (responsible for cognition) if either malfunctions -> ALTERED consc minor? may be hard to detect -consider multiple causes in struct (eg alcohol + falls -> head inj -> hypothermia) use Glasgow coma scale to assess  if <15/15 = altered coma = < or = 8 with NO EYE RESPONSE don't say 'semi-conscious, stuperous, obtunded ,etc -minor disturb consc -> delirium? -to be considered here need GCS <15 and  a) E <3, V<4, or M<5 (so >1 point drop in one+ domain) b) known or suspect head inj c) clin pict NOT suggest delirium -pt cna't give clear hist GET WITNESS ACCOUNT

1. circumstances of found (eg temp expose? poisons?)
2. speed, nature, surrounding events
   1. sudden onset? - SAH, seizure trauma
   2. gradual? SOL, metabolic
   3. recent flu like ill? mening, sepsis
   4. fluctuating? recurrent seizures
   5. trauma? RTA, fall, assault
3. DH (prescribed, OTC, alcohol, rec drug)
4. PMH

1. METABOLIC
   1. hypo/hyper glycemia; thermia; natremia
   2. hypothyroidism
   3. metabolic acidosis
2. DRUGS/TOXINS
   1. alcohol
   2. opioids, benzodiazepine, tricyclic antidepressants, barbiturates, etc
   3. 'recreational drugs'
   4. carbon monoxide/other cellular toxins eg cyanide
3. CNS causes
   1. TRAUMA
      1. intracranial bleed (extradural, subdural, subarachnoid, intracerebral)
   2. INFECTION
      1. meningitis, encephalitis, cerebral abscess, cerebral malaria
   3. STROKE
      1. cortex or brainstem
   4. SAHemmorhage
   5. EPILEPSY
   6. INTRACRANIAL space occupying lesion (eg py or 2ndry tumor)
   7. HYPERTENSIVE ENCEPHALOPATHY
   8. PSYCHOGENIC
4. ORGAN FAILURE
   1. shock
   2. resp fail (hypoxia and/or hypercapnia)
   3. renal fail (uremic encephalopathy)
   4. liver fail (heaptic encephalopathy)