What causes of abnormal mental status are particularly life threatening?
The list includes epidural hematoma, cerebral edema, brain neoplasms, cerebral infarctions, CSF shunt malfunction, meningitis, encephalitis, toxic ingestions, carbon monoxide poisoning, hypotension, hypoxia, and sepsis.
Nelson DS: Coma and altered level of consciousness. In Fleisher G, Ludwig S, Henretig FM (eds): Textbook of Pediatric Emergency Medicine, 6th ed. Philadelphia, Lippincott Williams & Wilkins, 2010, pp 176-186.