Treatment of delirium in the critically ill patient.

The clinical use of neuroleptics, benzodiazepines, narcotic analgesics, barbiturates, and neuromuscular blockers to manage delirium and agitation in the intensive-care setting is reviewed. Delirium is the most commonly encountered mental disturbance in critically ill patients and may be precipitated by factors such as physical illness, medications, pain, and emotional stress. If agitation cannot be controlled through nonpharmacologic means, pharmacologic intervention may be necessary. Haloperidol is the neuroleptic of choice for rapid control of delirium and agitation in the critically ill patient. It has few adverse effects in most patients, even at high doses, although it can cause extrapyramidal symptoms. Among the benzodiazepines, lorazepam should be considered a first-line agent. It may be used alone or in combination with haloperidol (or another neuroleptic). Midazolam is suitable for administration by continuous i.v. infusion in the intensive-care setting because of its water solubility, short half-life, and short duration of action. The sedative effects of narcotics may be advantageous in patients with both agitation and pain. Barbiturates are not recommended for routine use in the treatment of delirium and agitation. The use of neuromuscular blocking agents such as pancuronium bromide and metocurine iodide may be necessary when other therapies have failed. Haloperidol and the benzodiazepines, alone or in combination, are the drugs of choice for treatment of acute agitation and delirium in critically ill patients.