Altered Mental Status
GENERAL PRINCIPLES
Mental status changes have a broad differential diagnosis that includes neurologic (e.g., stroke, seizure, delirium), metabolic (e.g., hypoxemia, hypoglycemia), toxic (e.g., drug effects, alcohol withdrawal), and other etiologies.
Infection is a common cause of mental status changes in the elderly and in patients with underlying neurologic disease. Sundown syndrome refers to the appearance of worsening confusion in the evening and is associated with dementia, delirium, and unfamiliar environments.DIAGNOSIS
History and Physical Examination
• Focus particularly on medications, underlying dementia, cognitive impairment, neurologic or psychiatric disorders, and a history of alcohol and/or drug use.
• Physical examination generally includes vital signs, a search for sites of infection, a complete cardiopulmonary examination, and a detailed neurologic examination including mental status evaluation.
Diagnostic Testing
• Testing includes blood glucose, serum electrolytes, creatinine, CBC, urinalysis, and oxygen assessment.
• Other evaluation, including lumbar puncture, toxicology screen, cultures, thyroid function tests, noncontrast head CT, electroencephalogram, CXR, or ECG, should be directed by initial findings.
TREATMENT
Management of specific disorders is discussed in Chapter 27, Neurologic Disorders.
Medications
Agitation and psychosis may be features of a change in mental status. The antipsychotic haloperidol and the benzodiazepine lorazepam are commonly used in the acute management of these symptoms. Second- generation antipsychotics (risperidone, olanzapine, quetiapine, clozapine, ziprasidone, aripiprazole, paliperidone) are alternative agents that may lead to decreased incidence of extrapyramidal symptoms. All of these agents pose risks to elderly patients and those with dementia if given long term.
• Haloperidol is the initial drug of choice for acute management of agitation and psychosis. It has fewer active metabolites and fewer anticholinergic, sedative, and hypotensive effects than other antipsychotics but may have more extrapyramidal side effects.
• In low dosages, haloperidol rarely causes hypotension, cardiovascular compromise, or excessive sedation.
• Postural hypotension may occasionally be acute and severe after administration. IV fluids should be given initially for treatment.
• Use should be discontinued with prolongation of QTc >450 ms or 25% above baseline.
• Neuroleptic malignant syndrome (see Chapter 27, Neurologic Disorders).
• Lorazepam can also be used for agitation. Lorazepam has a short duration of action and few active
metabolites. Excessive sedation and respiratory depression can occur.
Nonpharmacologic Therapies
Patients with delirium of any etiology often respond to frequent reorientation, observance of the day-night light cycle, and maintenance of a familiar environment. These methods should be trialed before the use of the above medications if the patient is not a threat to themselves or care teams.