delirium
(di-lir'ē-ŭm 
)
[L. delirium, madness, insanity]
An acute, reversible state of disorientation, inattention, and confusion.
Incidence: Delirium is exceptionally common among older and hospitalized patients. It is found (in different surveys) in as few as 10% and as many as 90% of these populations.
Causes: Common causes include withdrawal from drugs and /or alcohol; side effects of medication; infections (esp. sepsis); pain; surgery or trauma; hypoxia; electrolyte and acid-base imbalances; sensory deprivation or sensory overload; dementia; hospitalization (esp. admission to an intensive care unit for longer than two days); depression (esp. but not exclusively in people 65 years or older).
Symptoms and Signs: Delirium is marked by disorientation without drowsiness; hallucinations or delusions; difficulty in focusing attention; inability to rest or sleep; and emotional, physical, and autonomic overactivity.
Diagnosis: The health care professional should consider delirium whenever an acute change in mental status occurs and esp. when the mental status of patients is sometimes clear but at other times is profoundly confused and disoriented. There is no diagnostic clinical laboratory, physiological, or imaging test for delirium.
Prevention: Preventive measures may sometimes reduce the risk of delirium in hospitalized patients. Such measures include providing glasses and hearing aids to patients with known sensory defects; mobilizing patients or providing range-of-motion activities several times each day and as early as possible during hospitalization; avoiding multiple new medications; maintaining hydration by encouraging oral fluid intake; using holistic measures to promote relaxation; introducing structured sleep protocols; reducing anxiety; and engaging family members or people with the care of delirious patients.
Treatment: Treatment involves determining the cause of the delirium and removing or resolving it if possible.
Impact on Health: Patients who experience an episode of delirium have reduced longevity compared to hospitalized patients with similar illnesses who do not; they also have an increased risk of prolonged cognitive impairment after the delirium resolves.
Patient Care: Supportive care consists of minimizing unanticipated, frightening, or invasive procedures; integrating orienting statements into normal conversation; and providing confused patients with a calm, supportive presence. When patients express deluded thoughts, it is important not to try to convince them that their perceptions are distorted. Speaking in a calm, clear voice, talking directly to the patient, using only simple statements and questions, and maintaining eye contact may be helpful. Maintaining caregiver consistency and encouraging family visiting are esp. beneficial. Delirious patients should be placed close to nursing stations so that they can be frequently observed. Physical protection from self-injury should be provided by bed alarms, wand er guards, or mattresses placed on the floor to decrease the likelihood of patients' falling. Delirious patients should be permitted to sleep without interruption. Pain that they experience should be treated with analgesic drugs that do not affect mental status. Large calendars and clocks should be provided to aid orientation. Natural light should be used to distinguish day and night. Other useful preventive interventions include limiting interfacility transfers and room changes as much as possible and providing complementary therapies to decrease agitation and aggression, e.g., music therapy, massage, and shared activities. Antipsychotic drugs and benzodiazepines may be used cautiously when other nonpharmacological interventions have failed.
acute d.Delirium that develops suddenly.
Variant: alcohol delirium
Delirium tremens.d. cordis Atrial fibrillation.
emergence d.Unusually intense delirium in a patient awakening from anesthesia.
febrile d.Delirium occurring with fever.
hypoactive d.Acute and reversible confusion, disorientation, and cognitive malfunction, without grossly obvious behavior changes.
d. of negation Cotard delusion.
d. of persecution Delirium in which the patient feels persecuted by those around him or her.
senile d.An intermittent or permanent delirium that may come on abruptly in old age or may be associated with senile dementia.
toxic d.Delirium resulting from exposure to or ingestion of a psychically active agent, e.g., jimson weed, lysergic acid diethylamide (LSD), mescaline, or psilocybin.
traumatic d.Delirium following injury or shock.
ABBR: DTs
The most severe expression of alcohol withdrawal syndrome. Although in most affected patients, recovery occurs within 3 to 5 days, about 15% may die, often as a result of comorbid illnesses or of complications of the disease itself. SYN: alcoholic delirium; alcohol withdrawal delirium; withdrawal delirium.SEE: alcoholism; alcohol withdrawal syndrome.
The disease is common; it is regularly diagnosed and managed in hospital ERs and ICUs.
The DTs are caused by abruptly tapering or stopping alcohol use after a period of heavy alcohol consumption.
Delirium tremens is marked by disorientation, anxiety, and restlessness, followed by visual, auditory, or tactile hallucinations, alcohol withdrawal seizures, and hyperactivity of the autonomic nervous system (evidenced by findings such as pupillary dilation, fever, tachycardia, uncontrolled hypertension, and profuse sweating).
The diagnosis for the DTs is made clinically (based on a history of alcohol cessation in a formerly heavy user). Conditions that may mimic delirium tremens should be excluded, e.g., when findings suggest a history of head trauma, meningitis, or sepsis.
Gradually tapering off of alcohol use, e.g., during supervised alcohol detoxification programs, prevents the signs and symptoms of alcohol withdrawal syndrome and the DTs.
Benzodiazepines are given to prevent or treat alcohol withdrawal seizures. Long-acting agents such as diazepam are effective, as are shorter-acting agents such as lorazepam. The active metabolites of diazepam are useful because they provide the patient with long-acting protection; the shorter duration of the action of lorazepam may be preferable in alcoholic patients with advanced liver disease. Hallucinations are treated with dopamine antagonists such as quetiapine. Beta blockers such as metoprolol are used to manage high blood pressure and tachycardia. Thiamine is given to prevent Wernicke encephalopathy. Folate is used for nutritional support.
Although in most affected patients, recovery occurs within 3 to 5 days, about 15% of affected patients may die, often as a result of comorbid illnesses or complications of the disease itself.
The patient’s status is best managed in an ICU or a well-staffed hospital unit in which frequent patient observations can be made and regular adjustments in medications can be given (according to symptom-driven protocols) when they are needed to prevent deterioration. Many patients require tracheal intubation and mechanical ventilation to protect the airway and support ventilation while sedating drugs are administered. Aggressive fluid, electrolyte, and nutritional support are often needed. After the patient’s crisis resolves, he or she should be referred to alcohol counseling. Long-term support of the patient, e.g., in programs such as Alcoholics Anonymous, may improve long-term care.
It is crucial to distinguish the signs and symptoms of alcoholic delirium from those caused by intracerebral hemorrhage, meningitis, or intoxication with substances other than alcohol. Evaluation of the patient suspected of having the DTs may therefore require neuroimaging, lumbar puncture, or drug screening.