Delirium is a serious disturbance in a person’s mental abilities that results in a decreased awareness of one’s environment and confused thinking. The onset of delirium is usually sudden, often within hours or a few days. Delirium can often be traced to one or more contributing factors, such as a severe or chronic medical illness, medication, infection, surgery, or drug or alcohol abuse.
The symptoms of delirium can be similar to dementia, but it is important to know that the two conditions are different. Unlike dementia, delirium is often a temporary condition and symptoms fluctuate throughout the day. Many disorders cause delirium, including conditions that deprive the brain of oxygen or other substances.
Delirium is broken down in the DSM-IV-TR into the categories listed below. The categories just mean that the delirium is caused by something different. The symptoms though are pretty consistent across the categories.
- Delirium due to a general medical condition
- Delirium due to multiple medical etiologies
- Delirium not otherwise specified
- Substance induced delirium
- Substance intoxication delirium
- Substance withdrawal delirium
Causes include:
- Alcohol or sedative drug withdrawal
- Drug abuse
- Electrolyte or other body chemical disturbances
- Infections such as urinary tract infections or pneumonia (more likely in people who already have brain damage from stroke or dementia)
- Poisons
- Surgery
- Older age
- Previous delirium episodes
- Visual or hearing impairment
- Poor nutrition or dehydration
- Severe, chronic or terminal illness
- Multiple medical problems or procedures
- Treatment with multiple drugs
- Certain medications (e.g. pain medications, sleep medications, allergy medications-antihistamines, SSRIs, mood stabilizers, anticonvulsants, asthma medications, Parkinson’s disease medications)
Symptoms include:
- Changes in alertness (usually more alert in the morning, less alert at night)
- Changes in feeling (sensation) and perception
- Changes in level of consciousness or awareness
- Changes in movement (for example, may be slow moving or hyperactive)
- Changes in sleep patterns, drowsiness
- Confusion (disorientation) about time or place
- Decrease in short-term memory and recall
- Unable to remember events since delirium began (anterograde amnesia)
- Unable to remember events before delirium (retrograde amnesia)
- Disrupted or wandering attention
- Inability to think or behave with purpose
- Problems concentrating
- Disorganized thinking
- Speech that doesn’t make sense (incoherent)
- Inability to stop speech patterns or behaviors
- Emotional or personality changes
- Anger
- Agitation
- Anxiety
- Apathy
- Depression
- Euphoria
- Irritability
- Incontinence
- Movements triggered by changes in the nervous system (psychomotor restlessness)
Testing for delirium includes the following:
- An exam of the nervous system (neurologic examination), including tests of feeling (sensation), thinking (cognitive function), and motor function
- Neuropsychological studies
Additional tests may include:
- Ammonia levels in the blood
- Blood chemistry (comprehensive metabolic panel)
- Blood gas analysis
- Chest x-ray
- Cerebrospinal fluid (CSF) analysis
- Creatine kinase level in blood
- Drug, alcohol levels (toxicology screen)
- Electroencephalogram (EEG)
- Head CT scan
- Head MRI scan
- Liver function tests
- Mental status test
- Serum magnesium
- Thyroid function tests
- Urinalysis
- Vitamin B1 and B12 levels
Treatment:
The type of treatment depends on what is causing the delirium. The goal of treatment is to control or reverse the symptoms.
Stopping or changing medications that worsen confusion, or that are not necessary, may improve mental function significantly. Medications that may worsen confusion include:
- Alcohol
- Analgesics, especially narcotics such as codeine, hydrocodone, morphine, or oxycodone
- Anticholinergics
- Central nervous system depressants
- Cimetidine
- Illicit drugs
- Lidocaine
Disorders that contribute to confusion should be treated. These may include:
- Anemia
- Decreased oxygen (hypoxia)
- Heart failure
- High carbon dioxide levels (hypercapnia)
- Infections
- Kidney failure
- Liver failure
- Nutritional disorders
- Psychiatric conditions (such as depression)
- Thyroid disorders
Treating medical and mental disorders often greatly improves mental function.
Medications may be needed to control aggressive or agitated behaviors. These are usually started at very low doses and adjusted as needed. Medications include:
- Antidepresssants (fluoxetine, citalopram), if depression is present
- Dopamine blockers (haloperidol, quetiapine, or risperidone are most commonly used)
- Sedatives (clonazepam or diazepam) in cases of delirium due to alcohol or sedative withdrawal
- Thiamine
Other treatments that may be helpful:
- Behavior modification to control unacceptable or dangerous behaviors
- Reality orientation to reduce disorientation
Works Cited:
- Delirium. Mayo Clinic. n.d. Web. 28 January 2013.