Consciousness - decreased

Also known as: Stuporous, Mental status - decreased, Loss of alertness, Decreased consciousness, Alertness - decreased, Changes in consciousness, Obtundation, Coma or Unresponsiveness

Definition

Decreased consciousness is reduced alertness or awareness.

Considerations

A persistent coma is called vegetative state.

Common Causes

Many conditions can cause decreased consciousness, including:

Home Care

A decrease in consciousness almost always require a doctor's attention, except perhaps when due to alcohol intoxication, simple fainting, or a previously recognized seizure disorder.

See the article on seizures for tips on how to care for a person who is having a seizure.

Persons with epilepsy or other seizure disorder should carry a Medic-Alert bracelet or pendant describing their condition. Such individuals should avoid situations that have previously triggered a seizure.

Call your health care provider if

See medical help if someone has unexplained, decreased consciousness. Call your local emergency number (such as 911) if normal consciousness does not return quickly.

What to expect at your health care provider's office

Most often, a person with decreased consciousness will be evaluated in an emergency room setting.

The doctor will perform a physical examination. The exam will include a detailed look at the cardiovascular, respiratory, and nervous systems.

The health care team will ask questions about the person's medical history and symptoms, including

  • Time pattern
    • When did the decreased consciousness occur?
    • How long did it last?
    • Has it ever happened before? If so, how many times?
    • Did the person behave the same way on previous episodes?
  • Medical history
    • Does the person have known epilepsy or seizure disorder?
    • Does the person have diabetes?
    • Has the person been sleeping well?
    • Has there been a recent head injury?
  • Other
    • What medications does the person take?
    • Does the person habitually use alcohol or drugs?
    • What other symptoms are present?

Tests that may be done include:

Treatment depends on the underlying cause of the decreased consciousness. How well a person does depends on the cause of the condition. The longer the person has a decreased or altered level of consciousness, the worse the outcome.

References

Blok BK, Newman TM. Syncope. In: Tintinalli JE, Kelen GD, Stapczynski JS, Ma OJ, Cline DM, eds. Emergency Medicine: A Comprehensive Study Guide. 6th ed. New York, NY: McGraw-Hill; 2004:chap 52.

Huff JS. Altered mental status and coma. In: Tintinalli JE, Kelen GD, Stapczynski JS, Ma OJ, Cline DM, eds. Emergency Medicine: A Comprehensive Study Guide. 6th ed. New York, NY: McGraw-Hill; 2004:chap 259.

Kirsch TD. Head injury. In: Tintinalli JE, Kelen GD, Stapczynski JS, Ma OJ, Cline DM, eds. Emergency Medicine: A Comprehensive Study Guide. 6th ed. New York, NY: McGraw-Hill; 2004:chap 255.

See also:

  • Symptoms

    Skin discoloration - bluish

    Cyanosis of the nail bed

    Cyanosis is a bluish color to the skin or mucus membranes due to a lack of oxygen in the blood.

  • Disease

    Epilepsy

    Brain structures

    Epilepsy is a brain disorder involving repeated, spontaneous of any type. Seizures (“fits,” convulsions) are episodes of disturbed brain function that cause changes in attention or behavior. They are caused by abnormally excited electrical signals in the brain. See also:

  • Symptoms

    Seizures

    A seizure is the physical findings or changes in behavior that occur after an episode of abnormal electrical activity in the brain. See also: (seizures in children with high fever)

  • Injury

    Head injury

    Bicycle helmet - proper usage

    A head injury is any trauma that leads to injury of the scalp, skull, or brain. The injuries can range from a minor bump on the skull to serious brain injury. Head injury is classified as either closed or open (penetrating). A closed head injury means you received a hard blow to the head from ...

  • Injury

    Shock

    Shock

    Shock is a life-threatening condition that occurs when the body is not getting enough blood flow. This can damage multiple organs. Shock requires immediate medical treatment and can get worse very rapidly.

  • Special Topic

    Central nervous system

    Vertebra and spinal nerves

    The central nervous system is composed of the brain and spinal cord. Your brain and spinal cord serve as the main “processing center” for the entire nervous system, and control all the workings of your body.

  • Disease

    Alcoholism and alcohol abuse

    Liver fattening, CT scan

    Alcoholism (alcohol dependence) and alcohol abuse are two different forms of problem drinking. Alcoholism occurs when a person shows signs of physical addiction to alcohol (for example, tolerance and withdrawal) and continues to drink, despite problems with physical health, mental health, and ...

  • Injury

    Unconsciousness - first aid

    Unconsciousness is when a person is unable to respond to people and activities. Often, this is called a coma or being in a comatose state. Other changes in awareness can occur without becoming unconscious. Medically, these are called “altered mental status” or “changed mental ...

  • Symptoms

    Fainting

    Fainting is a temporary loss of consciousness due to a drop in blood flow to the brain. The episode is brief (lasting less than a couple of minutes) and is followed by rapid and complete recovery. You may feel light-headed or before fainting. A longer, deeper state of is often called a coma.

Review date:
April 21, 2009
Reviewed by:
Jacob L. Heller, MD, Emergency Medicine, Virginia Mason Medical Center, Seattle, Washington, Clinic. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
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