Altered mental status
This page is for adult patients. For pediatric patients, see: altered mental status (peds)
Background
- Acute alteration in brain function
- May include alteration of arousal or awareness, thought content, memory, or attention
- Both cerebral cortices or brainstem must be affected
- Delirium vs dementia vs other organic pathology vs functional (psychiatric)
- Must quickly determine if coma is from diffuse or focal impairment
Clinical Features
- Depends on cause
- Diffuse brain dysfunction - lack of focal findings
- Focal brain dysfunction - hemiparesis, loss of motor tone, loss of ocular reflexes
- Important to differentiate diffuse brain dysfunction from localized lesion as a patient may appear confused due to visual deficit, dysphasia, etc.
Differential Diagnosis
Altered mental status
Diffuse brain dysfunction
- Hypoxic encephalopathy
- Acute toxic-metabolic encephalopathy (Delirium)
- Hypoglycemia
- Hyperosmolar state (e.g., hyperglycemia)
- Electrolyte Abnormalities (hypernatremia or hyponatremia, hypercalcemia)
- Organ system failure
- Hepatic Encephalopathy
- Uremia/Renal Failure
- Endocrine (Addison's disease, Cushing syndrome, hypothyroidism, myxedema coma, thyroid storm)
- Hypoxia
- CO2 narcosis
- Hypertensive Encephalopathy
- Toxins
- TTP / Thrombotic thrombocytopenic purpura
- Alcohol withdrawal
- Drug reactions (NMS, Serotonin Syndrome)
- Environmental causes
- Deficiency state
- Wernicke encephalopathy
- Subacute Combined Degeneration of Spinal Cord (B12 deficiency)
- Vitamin D Deficiency
- Zinc Deficiency
- Sepsis
- Osmotic demyelination syndrome (central pontine myelinolysis)
- Limbic encephalitis
Primary CNS disease or trauma
- Direct CNS trauma
- Diffuse axonal injury
- Subdural/epidural hematoma
- Vascular disease
- SAH
- Stroke
- Hemispheric, brainstem
- CNS infections
- Neoplasms
- Paraneoplastic Limbic encephalitis
- Malignant Meningitis
- Pancreatic Insulinoma
- Seizures
- Nonconvulsive status epilepticus
- Postictal state
- Dementia
Psychiatric
Evaluation
AMS Workup
Common Orders
Consider Based on Clinical Situation
- Blood and urine cultures
- Ammonia level
- Tylenol/Aspirin level
- LP
- Serum Osm
- Coags
- Cortisol
- ABG/VBG
- CO level
Management
- Patients with focal findings may have surgically treatable cause
- Coma cocktail
- Treat underlying cause
Disposition
- Most frequently admission, unless of a chronic and known etiology