delirium (redirected from deliriums)

Delirium 

Definition

Delirium is a state of mental confusion that develops quickly and usually fluctuates in intensity.

Description

Delirium is a syndrome, or group of symptoms, caused by a disturbance in the normal functioning of the brain. The delirious patient has a reduced awareness of and responsiveness to the environment, which may be manifested as disorientation, incoherence, and memory disturbance. Delirium is often marked by hallucinations, delusions, and a dream-like state.

Delirium affects at least one in 10 hospitalized patients, and is a common part of many terminal illnesses. Delirium is more common in the elderly than in the general population. While it is not a specific disease itself, patients with delirium usually fare worse than those with the same illness who do not have delirium.

Causes and symptoms

Causes

There are a large number of possible causes of delirium. Metabolic disorders are the single most common cause, accounting for 20-40% of all cases. This type of delirium, termed "metabolic encephalopathy," may result from organ failure, including liver or kidney failure. Other metabolic causes include diabetes mellitus, hyperthyroidism and hypothyroidism, vitamin deficiencies, and imbalances of fluids and electrolytes in the blood. Severe dehydration can also cause delirium.

Drug intoxication ("intoxication confusional state") is responsible for up to 20% of delirium cases, either from side effects, overdose, or deliberate ingestion of a mind-altering substance. Medicinal drugs with delirium as a possible side effect or result of overdose include:

• anticholinergics, including atropine, scopolamine, chlorpromazine (an antipsychotic), and diphenhydramine (an antihistamine)
• sedatives, including barbiturates, benzodiazepines, and ethanol (drinking alcohol)
• antidepressant drugs
• anticonvulsant drugs
• nonsteroidal anti-inflammatory drugs (NSAIDs), including ibuprofen and acetaminophen
• corticosteroids, including prednisone
• anticancer drugs, including methotrexate and procarbazine
• lithium
• cimetidine
• antibiotics
• L-dopa

Delirium may result from ingestion of legal or illegal psychoactive drugs, including:

• ethanol (drinking alcohol)
• marijuana
• LSD (lysergic acid diethylamide) and other hallucinogens
• amphetamines
• cocaine
• opiates, including heroin and morphine
• PCP (phencyclidine)
• inhalants

Drug withdrawal may also cause delirium. Delirium tremens, or "DTs," may occur during alcohol withdrawal after prolonged or intense consumption. Withdrawal symptoms are also possible from many of the psychoactive prescription drugs.

Poisons may cause delirium ("toxic encephalopathy"), including:

• solvents, such as gasoline, kerosene, turpentine, benzene, and alcohols
• carbon monoxide
• refrigerants (Freon)
• heavy metals, such as lead, mercury, and arsenic
• insecticides, such as Parathion and Sevin
• mushrooms, such as Amanita species
• plants such as jimsonweed (Datura stramonium) and morning glory (Ipomoea spp.)
• animal venoms

Other causes of delirium include:

• infection
• fever
• head trauma
• epilepsy
• brain hemorrhage or infarction
• brain tumor
• low blood oxygen (hypoxemia)
• high blood carbon dioxide (hypercapnia)
• post-surgical complication

Symptoms

The symptoms of delirium come on quickly, in hours or days, in contrast to those of dementia, which develop much more slowly. Delirium symptoms typically fluctuate through the day, with periods of relative calm and lucidity alternating with periods of florid delirium. The hallmark of delirium is a fluctuating level of consciousness. Symptoms may include:

• decreased awareness of the environment
• confusion or disorientation, especially of time
• memory impairment, especially of recent events

• hallucinations
• illusions and misinterpreted stimuli
• increased or decreased activity level
• mood disturbance, possibly including anxiety, euphoria or depression
• language or speech impairment

Diagnosis

Delirium is diagnosed through the medical history and recognition of symptoms during mental status examination. The most important part of diagnosis is determining the cause of the delirium. Tests may include blood and urine analysis for levels of drugs, fluids, electrolytes, and blood gases, and to test for infection; lumbar puncture ("spinal tap") to test for central nervous system infection; x ray, computed tomography scans (CT), or magnetic resonance imaging (MRI) scans to look for tumors, hemorrhage, or other brain abnormality; thyroid tests; electroencephalography (EEG); electrocardiography (ECG); and possibly others as dictated by the likely cause.

Treatment

Treatment of delirium begins with recognizing and treating the underlying cause. Delirium itself is managed by reducing disturbing stimuli, or providing soothing ones; use of simple, clear language in communication; and reassurance, especially from family members. Physical restraints may be needed if the patient is a danger to himself or others, or if he insists on removing necessary medical equipment such as intravenous lines or monitors. Sedatives or antipsychotic drugs may be used to reduce anxiety, hallucinations, and delusions.

Prognosis

Persons with delirium usually have a worse prognosis for the underlying disease than the person without delirium. Nonetheless, those without terminal illness usually recover from delirium. They may not, however, regain all their original cognitive abilities, and may be left with some permanent impairments, including fatigue, irritability, difficulty concentrating, or mood changes.

Prevention

Prevention of delirium is focused on treating or avoiding its underlying causes. The most preventable forms are those induced by drugs. Strategies for reducing delirium include following prescriptions, consulting the prescribing physician immediately if symptoms occur, and consulting the physician before discontinuing the drug, even if it has been ineffective; avoiding intoxication with legal or illegal drugs, and seeking professional assistance before suddenly discontinuing an addictive drug such as alcohol or heroin; maintaining good nutrition, which promotes general health and can minimize the likelihood of delirium from alcohol intoxication and withdrawal; and avoiding exposure to solvents, insecticides, heavy metals, or biological poisons in the home or workplace.

Resources

Books

Guze, Samuel, editor. Adult Psychiatry. Mosby Year Book, 1997.

Key terms

Dementia — A loss of mental ability severe enough to interfere with functioning. While dementia and delirium have some of the same symptoms, dementia has a much slower onset.

Electroencephalogram (EEG) — A chart of the brain wave patterns picked up by electrodes placed on the scalp. This is useful for diagnosing central nervous system disorders.

Encephalopathy — A brain dysfunction or disorder.

---

delirium /de·lir·i·um/ (dĕ-lēr´e-um) pl. deli´ria   a mental disturbance of relatively short duration usually reflecting a toxic state, marked by illusions, hallucinations, delusions, excitement, restlessness, impaired memory, and incoherence.

---

alcohol withdrawal delirium  that caused by cessation or reduction in alcohol consumption, typically in alcoholics with many years of heavy drinking, characterized by autonomic hyperactivity, such as tachycardia, sweating, and hypertension, a coarse, irregular tremor, and delusions, vivid hallucinations, and wild, agitated behavior.

delirium tre´mens  alcohol withdrawal d.

---

de·lir·i·um (d-lîr-m)

n. pl. de·lir·i·ums or de·lir·i·a (--)

A temporary state of mental confusion resulting from high fever, intoxication, shock, or other causes, and characterized by anxiety, disorientation, memory impairment, hallucinations, trembling, and incoherent speech.

---

delirium

[dilir′ē·əm]

Etymology: L, delirare, to rave

1 a state of frenzied excitement or wild enthusiasm.

2 an acute organic mental disorder characterized by confusion, disorientation, restlessness, clouding of the consciousness, incoherence, fear, anxiety, excitement, and, often, illusions; hallucinations, usually of visual origin; and, at times, delusions. The condition is caused by disturbances in cerebral functions that may result from a wide range of metabolic disorders, including nutritional deficiencies and endocrine imbalances; postpartum or postoperative stress; ingestion of toxic substances, such as various gases, metals, or drugs, including alcohol; and other causes of physical and mental shock or exhaustion. The symptoms are usually of short duration and reversible with treatment of the underlying cause; in extreme cases, however, in which the toxic condition is exceedingly severe or prolonged, permanent brain damage may occur. Kinds of delirium include acute delirium, chronic delirium, delirium tremens, exhaustion delirium, senile delirium, and traumatic delirium. Compare dementia. delirious, adj.

observations There is a rapid onset and acute change in mentation. Manifestations include fluctuating levels of consciousness; disorientation; impaired memory; inability to maintain or shift attention; irritability, agitation, restlessness, and hyperactivity; perceptual disturbance, hallucinations, and delusions; rambling and fragmented speech; and impaired sleep-wake cycle. There are typically lucid intervals with symptoms worsening at night. Duration of symptoms is limited. There are four DSM-IV diagnostic criteria for delirium: (1) disturbance of consciousness with reduced awareness and diminished abilities to focus and to maintain or shift attention; (2) a change in cognition, such as disorientation, memory loss, or language disturbance; (3) the development of the disturbance over a period of hours to days, with fluctuation during the day; and (4) evidence from clinical exam and/or lab findings that the disturbance is caused by physiologic consequences of a medical condition. Delirium places medically ill individuals at greater risk for medical complications (pneumonia and decubitus) and is associated with functional decline and institutional placement. Delirium may lead to dementia.

interventions Intervention centers around removal or withdrawal from toxic agents (alcohol and barbiturates) and IV sedation with antianxiety and antipsychotic agents for agitation, seizure activity, and tremors. Adequate fluid and electrolyte balance is also crucial.

nursing considerations Nursing care during an acute episode of delirium is aimed at support, reduction of confusion and agitated behavior, and prevention of injury. Interventions include seizure precautions, safety precautions (e.g., prevent wandering and climbing over bedrails), environmental control (adequate lighting, noise reduction, clear space, removal of hazards, avoidance of sensory extremes, and allowance for adequate sleep), reorientation procedures (e.g., clocks, calendars, familiar objects, use of glasses and hearing aids), consistency of caretakers, and family involvement. Restraints should be avoided. Tactics to prevent delirium are crucial in susceptible individuals (e.g., those with chronic or mental illness, altered sensory perception, or neurologic disease; those with elevated ammonia, increased blood urea nitrogen, or hypoxia; those on CNS stimulants or depressants), and those in altered environments (e.g., ICU, isolation, incubators, and institutions). This is accomplished by assessing and removing noxious environmental stimuli while increasing meaningful stimuli. Reduction of risk factors (e.g., sleep deprivation, visual or hearing impediments, adverse medications, dehydration, and pain) and use of orienting features (e.g., clocks, calendars, windows, and familiar objects) are important, as is maintaining verbal and nonverbal contact, with judicious use of touch. Structuring and explaining routines and procedures and interpreting sights, sounds, and smells in the environment are also crucial in preventing delirium.

---

delirium (delir´ēm),

n a condition of mental excitement, confusion, and clouded sensorium, usually accompanied by hallucinations, illusions, and delusions; precipitated by toxic factors in diseases or drugs.

delirium tremens (DT),

n See alcohol withdrawal delirium.

---

delirium

Neurology An acute organic brain disorder caused by a defect in cognate functions with global impairment and a ↓ clarity of awareness of the environment, which may progress or regress Etiology May be multifactorial–eg, due to toxins; substance abuse; acute psychosis, medication–eg anticholinergics; anemia, brain lesions–eg 1º tumors or metastases; chemotherapy–eg, MTX, corticosteroids, asparginase, vincristine; endocrinopathies–eg, hypoglycemia; fever; infection; metabolic derangement–eg, ↑ Ca2+, ↓ Na+ paraneoplastic syndromes Clinical Disturbance of sleep-wake cycle, with insomnia and/or daytime drowsiness, altered psychomotor activity, perceptual disturbances, and behavior changes–eg anger, anxiety, depression, fear, irritability, paranoia, withdrawal, most prominent at night Diagnosis EEG–slowing of brain waves; cognitive capacity screening examination; mini-mental state test; trail-making B test. See Black patch delirium, Fatal excited delirium, Pseudodelirium. Cf Dementia.