Delirium is a difficult symptom that often occurs near the end of life. Varying levels of loss of consciousness, ability to think and perception can occur within short periods of time. Challenges for physicians who treat these patients include a frightened patient, upset loved ones, helping the patient make optimal use of lucid periods; and recognizing the mental changes as possible evidence of approaching death. Proper treatment can relieve much of the stress associated with delirium for the patient and others. Casarett and colleagues reviewed the diagnosis and management of delirium near the end of life.
To be able to recognize periods of delirium, the physician must know the patient's baseline mental state. This baseline can be constructed through discussions with patients and family members. Evaluation for delirium involves testing the patient's cognition and attention using a validated test such as the Mini-Mental State Examination. Several bedside-administered scales including the Confusion Assessment Method, the Memorial Delirium Assessment Scale, and the Delirium Symptom Interview, are available to distinguish delirium from other causes of mental status changes. Once delirium has been diagnosed, it can be further characterized as hyperactive, hypoactive, or mixed (in which the patient varies between agitation and quiet).
Causes of delirium can be explored through the medical history, physical examination, and laboratory testing (see accompanying table). Usually, delirium is multifactorial, and other causes should be identified. The physical examination should indicate hypotension, periods of apnea or hypo-oxygenation, fever, focal neurologic changes, volume depletion, or asterixis. Laboratory testing can include a complete blood count with differential, electrolytes, blood urea nitrogen, creatinine, calcium, magnesium, phosphorus, glucose, urinalysis, and oxygen saturation determinations.
Treatment of delirium must be individualized and, in some situations, may be as simple as providing the family and patient with reassurance. Preventive measures include cognitive activity and helping patients remain oriented to their surroundings. Relaxation and improvement in mobility are also helpful. Pharmacologic treatment should be used to bring patients closer to their baseline mental status. The wishes of the patient and family should be considered when initiating pharmacologic treatment. Haloperidol may reduce agitation and improve cognitive function. Newer agents, such as risperidone, clozapine, and olanzapine, have fewer side effects, but their response time is much longer. If sedation is used, short-acting medications such as lorazepam, midazolam, and propofol are useful.
The authors conclude that good end-of-life care often requires management of delirium. If delirium is distressing to the patient, it should be treated with the goal of restoring the patient to his or her baseline level of cognition.