|
Definition:
Delirium is a condition of severe confusion and rapid changes in
brain function. It is usually caused by a treatable physical or
mental illness.
Alternative Names:
Acute confusional state; Acute brain syndrome
Causes, incidence, and risk factors:
Acute confusional states most often result from physical or
mental illness and are usually temporary and reversible. Disorders
that cause delirium are numerous and varied. They may include
conditions that deprive the brain of oxygen or other substances.
Delirium may be caused by diseases of body systems other than the
brain, by poisons, by fluid/electrolyte or acid/base disturbances,
and by other serious, acute conditions. Infections such as urinary
tract infections or pneumonia may trigger delirium in individuals
with pre-existing brain damage (prior strokes, dementia).
Patients with more severe pre-existing brain injury are more
likely to develop delirium from additional illness.
Symptoms:
Delirium involves a rapid alternation between mental states (for
example, from lethargy to agitation and back to lethargy), with
attention disruption, disorganized thinking, disorientation, changes
in sensation and perception, and other symptoms.
- attention disturbance (disrupted or wandering attention)
- inability to maintain goal directed, purposeful thinking
or behavior
- inability to concentrate
- disorganized thinking, evidenced by
- incoherent speech
- inability to stop speech patterns or behaviors
- disorientation to time or place
- changes in sensation and perception (increases the
disorientation)
- may precipitate illusions or hallucinations
- altered level of consciousness or awareness
- altered sleep patterns, drowsiness
- alertness may vary, usually more alert in the morning, less
alert at night (see drowsiness)
- decrease in short-term memory and recall
- unable to recall events since onset of delirium (anterograde
amnesia)
- unable to recall past events (retrograde amnesia)
- changes in motor activities, movement (for example, may be
lethargic or slow moving)
- movements triggered by changes in the nervous system
(psychomotor restlessness)
- emotional or personality changes
- anxiety
- anger
- apathy
- depression
- euphoria
- irritability
Signs and tests:
Neurologic examination may reveal abnormalities, including abnormal
reflexes and abnormal levels of normal reflexes. Psychologic studies
and tests of sensation, cognitive function, and motor function may
be abnormal.
The specific lesion, extent of damage, and cause of delirium may be
indicated by the results of tests and procedures, including, but not
limited to:
- serum electrolytes
- blood chemistry (chem-20)
- serum calcium
- glucose test
- serum magnesium - test
- CPK
- liver function tests
- ammonia levels
- thyroid stimulating hormone level
- thyroid function tests
- B-12 level
- drug, alcohol levels (toxicology screen)
- urinalysis
- blood gas analysis
- EEG, electroencephalograph
- head CT scan
- head MRI scan
- CSF (cerebrospinal fluid) analysis
- chest X-ray
Treatment:
The goal of treatment is to control or reverse the cause of the
symptoms, and will vary with the specific condition causing
delirium. The person should be in a pleasant, comfortable,
non-threatening, physically safe environment for diagnosis and
initial care. Hospitalization may be required for a short time.
Stopping or changing medications that worsen confusion, or that are
not essential to the care of the person, may improve cognitive
functioning even before treatment of the underlying disorder.
Medications that may worsen confusion include anticholinergics,
analgesics, cimetidine, central nervous system depressants,
lidocaine, and other medications (including alcohol and illegal
drugs).
Disorders that contribute to confusion should be treated. These may
include heart failure, decreased oxygen (hypoxia), excessive carbon
dioxide levels (hypercapnia), thyroid disorders, anemia, nutritional
disorders, infections, kidney failure, liver failure, and
psychiatric conditions (such as depression). Correction of
co-existing medical and psychiatric disorders often greatly improves
mental functioning.
Medications may be required to control aggressive or agitated
behaviors or behaviors that are dangerous to the person or to
others. These are usually given in very low doses, with adjustment
as required.
Medications that may be considered for use include:
- thiamine
- sedating medications such as clonazepam or diazepam
- serotonin-affecting drugs (trazodone, buspirone)
- dopamine blockers (such as haloperidol, olanzapine,
Risperdal, clozapine)
- fluoxetine, imipramine, Celexa (may help stabilize mood)
Sensory functioning should be evaluated and augmented as needed by
the use of hearing aids, glasses, or cataract surgery.
Formal psychiatric treatment may be necessary. Behavior modification
may be helpful for some people to control unacceptable or dangerous
behaviors. This consists of rewarding appropriate or positive
behaviors and ignoring inappropriate behaviors (within the bounds of
safety). Reality orientation, with repeated reinforcement of
environmental and other cues, may help reduce disorientation.
Expectations (prognosis):
The outcome varies. Acute disorders that cause delirium may
co-exist with chronic disorders that cause dementia. Acute brain
syndromes may be reversible with treatment of the underlying cause.
Delirium often lasts only about 1 week, although it may take
several weeks for cognitive function to return to normal levels.
Full recovery is common.
Complications:
- loss of ability to function or care for self
- loss of ability to interact
- may progress to stupor or coma
- side effects of medications used to treat the disorder
- other complications vary depending on the causative disorder
Calling your health care provider:
Call your health care provider if a rapid change in mental status
occurs.
Prevention:
Treatment of causative disorders and conditions reduces the risk
of delirium.
Healthcentral 2005
Back to
the top
  |
