TOC  |  Neurology


Quick Evaluation: Vital signs; evaluation for head injury or CVA, seizures, meningitis, or sepsis; alcohol or drug/medication history, glucose, oxygen, creatinine, liver function tests.

Until proven otherwise, a sudden change in behavior after age 40 should be considered to be delirium. Delirium is a true medical emergency because many of the causes such as anoxia, hypoglycemia, meningitis, and alcohol withdrawal are potentially lethal and reversible.

Effective management depends on prompt recognition of the condition, diagnosis and treatment of the underlying cause, management of agitation and disruptive behavior, and provision of general supportive care.

All nonessential drugs should be eliminated. Laboratory testing may uncover metabolic problems and fluid or electrolyte disturbances, which should be corrected without delay. Indications for brain imaging depend on the clinical situation. Although brain imaging often uncovers preexisting central nervous system disease, a comprehensive medical evaluation is still needed to identify the precipitating illness, which usually is located outside the nervous system.

A. Toxic or Metabolic causes:

B. Primary cerebral:

C. Underlying brain disease of various etiologies:





1. Metabolic: Hypoglycemia, Hyponatremia, Hypernatremia, Hypercalcemia, Carbon Dioxide Narcosis, Azotemia, Ketoacidosis, Hyperglycemic Coma (dehydration, hyperglycemia), Hepatic Encephalopathy, Nitrogen Narcosis - scuba diving

2. Toxic Encephalopathies: Alcohol - acute intoxication, withdrawal syndrome, Korsikoff Syndrome, Psychoactive Drugs, Salicylates, Heavy Metals

3. Intracranial lesions: Hemorrhage: subarachnoid, subdural, intracerebral, Cerebral infarction: thromboembolic stroke, Cerebral tumor, Cerebral abscess, Meningitis, Encephalitis, Epilepsy and Post-Ictal State

4. Neuropsychiatric Disease  

Outlines in Clinical Medicine on Physicians' Online 2000
Riordan SM and Williams R. 1997. NEJM. 337(7):473