Delirium is a clinical state characterized by an acute change in a person’s mental status. It usually comes on quickly (over hours or days). It is marked by extreme, fluctuating changes, including:

• Changes in perception and sensation

• Difficulties with ability to:

• • Focus

• • Sustain and shift attention

• • Think and reason rationally

• • Function normally

• • Communicate clearly

Causes

Hundreds of underlying causes can result in delirium. Some of the most common causes include:

• Serious medical condition, such as:

• • Brain tumor

• • Kidney failure

• • Stroke

• • Low or high blood sugar levels

• Serious illness, such as:

• • Meningitis

• • Cancer

• • Heart attack

• Injury, such as a severe head injury or broken bone

• Surgery

• Infection, such as pneumonia or urinary tract infections

• Alcohol or drug abuse

• Withdrawal from alcohol or drug abuse

• Toxic effects of medications

• Toxins

• Sleep deprivation

• Severe constipation

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. People most at risk of delirium include:

• People with a terminal illness, especially just prior to death

• People with a serious illness

• The elderly

• Cancer patients

• AIDS patients

• People who are severely sleep deprived

• Patients in the immediate period after surgery

• Patients with:

• • Burns

• • Central nervous system problems (eg, strokes, seizures, or tumors)

• Patients (especially hospitalized patients) who are:

• • Visually or hearing impaired

• • Immobile

• • Dehydrated

• • Constipated

• • Memory impaired

Symptoms

Symptoms usually come on quickly. They can vary in severity, depending on the underlying cause. Symptoms can last for days, weeks, or longer. Symptoms are usually worse at night. Symptoms of delirium can include:

• Inability to pay attention

• Confusion

• Memory problems

• Language disturbances

• Disorientation, especially in regard to:

• • Time of day

• • Where one is

• • Who one is

• Severe:

• • Misinterpretations – for example, thinking a doctor who is trying to help you is trying to hurt you

• • Illusions – for example, thinking someone is someone else

• • Hallucinations – seeing, hearing, or feeling things that aren’t there

• • Emotional disturbances – such as suddenly becoming very angry, fearful, or withdrawn for no apparent reason

Diagnosis

The doctor will ask about symptoms and medical history, and perform a thorough physical exam. The doctor will ask specific questions about:

• Present injury or illness

• Use of medications or illicit drugs

• Time when mental state changed

• How (and how fast) the mental state changed

There are many tests that may be used to help diagnose delirium. Depending on the specific case, any or all of these tests may be done, including:

• Blood Electrolytes – to measure levels of sodium, potassium, and calcium

• Kidney and Liver Function Tests

• Blood Glucose Levels

• CBC (Complete Blood Count)

• Blood Vitamin Levels – such as vitamin B12 and folate

• Thyroid Function Tests

• Blood Cultures – to look for signs of infection

• Spinal Fluid Culture – to look for signs of infection

• Urine Examination and Culture – to look for signs of infection

• Arterial Blood Gas – to check oxygen levels in the blood

• Toxicology Testing – to search for any illicit drugs in the body

• Blood Levels of Medications

• Chest X-ray – to look for signs of pneumonia

• Electrocardiogram (ECG, EKG) – a test that records the heart's activity by measuring electrical currents through the heart muscle

• CT Scan of the head – a type of x-ray that uses a computer to make images of the inside of the head

• MRI of the head – a test that uses magnetic waves to make images of the inside of the head

• Electroencephalogram (EEG) – a test that record's the brain's activity by measuring electrical currents through the brain

Treatment

Delirium is first treated by identifying and treating the underlying cause. Then, symptoms are treated through medications, psychologic management, and environmental and supportive intervention.

Treatments may include:

Medication – Drugs used to treat symptoms of delirium include:

• High potency antipsychotic medications such as Haldol

• Benzodiazepines – These drugs are only used to treat delirium caused by alcohol withdrawal or benzodiazepine withdrawal.

• Cholinergic medications – These drugs are only used to treat delirium caused by anticholinergic medications.

• Vitamins – Specific vitamin supplements are given if the delirium is caused by a deficiency

In addition, medications that might worsen confusion and are not essential to the patient may be stopped.

Psychologic management – This type of therapy involves helping the patient to:

• Feel more safe and comfortable

• Identify the cause of the delirium

• Improve the ability to function

• Calm down and feel less anxious

Environmental and supportive intervention – This type of treatment can be done by doctors, nurses, and/or caretakers of the patient. It is aimed at reorienting the patient to his or her surroundings and reducing the patient’s anxiety. It can involve actions such as:

• Placing a clock and calendar in the patient’s room

• Darkening the room at night and providing natural light during the day time hours

• Maintaining a quiet, noise-free room

• Reminding the patient often of the day and time, where they are, and why they are there

• Placing familiar objects around the patient (eg, family photographs or objects from home)

Prevention

A number of steps have been shown to help prevent delirium in hospitalized patients at risk for delirium. These steps include:

• Using memory orientation aids

• Listening to relaxation tapes

• Doing very light exercise (when possible and if recommended by your doctor)

• Using vision and hearing aids (when necessary)

• Drinking plenty of fluids (to prevent dehydration)

Delirium is difficult to prevent because it has so many possible underlying causes and it comes on so suddenly.

RESOURCES:

American Association of Community Psychiatrists
http://www.comm.psych.pitt.edu

American Psychiatric Association
http://www.psych.org

National Institute of Mental Health
http://www.nimh.nih.gov

References:

American Psychiatric Association website. Available at: http://www.psych.org.

The Merck Manual of Medical Information. Simon and Schuster, Inc.; 2000.

National Institutes of Mental Health website. Available at: http://www.nimh.nih.gov.