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Unconsciousness - first aid

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Illustrations

Recovery position - series
Recovery position - series

Alternative Names    Return to top

Loss of consciousness - first aid; Coma - first aid; Mental status change; Altered mental status

Definition    Return to top

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 status." They include sudden confusion, disorientation, or stupor.

Unconsciousness and any other SUDDEN change in mental status must be treated as a medical emergency.

If someone is awake but less alert than usual, ask a few simple questions, such as:

Wrong answers or an inability to answer suggest a change in mental status.

Considerations    Return to top

Being asleep is not the same thing as being unconscious. A sleeping person will respond to loud noises or gentle shaking -- an unconscious person will not.

An unconscious person cannot cough or clear his or her throat. This can lead to death if the airway becomes blocked.

Causes    Return to top

Unconsciousness can be caused by nearly any major illness or injury, as well as substance abuse and alcohol use.

Brief unconsciousness (or fainting) is often caused by dehydration, low blood sugar, or temporary low blood pressure. However, it can also be caused by serious heart or nervous system problems. Your doctor will determine if you need tests.

Other causes of fainting include straining during a bowel movement, coughing very hard, or breathing very fast (hyperventilating).

Symptoms    Return to top

The person will be unresponsive (does not respond to activity, touch, sound, or other stimulation).

The following symptoms may occur after a person has been unconscious:

First Aid    Return to top

  1. Call or tell someone to call 911.
  2. Check the person's airway, breathing, and pulse frequently. If necessary, begin rescue breathing and CPR.
  3. If the person is breathing and lying on the back, and you do not think there is a spinal injury, carefully roll the person toward you onto the side. Bend the top leg so both hip and knee are at right angles. Gently tilt the head back to keep the airway open. If breathing or pulse stops at any time, roll the person on to his back and begin CPR.
  4. If you think there is a spinal injury, leave the person where you found them (as long as breathing continues). If the person vomits, roll the entire body at one time to the side. Support the neck and back to keep the head and body in the same position while you roll.
  5. Keep the person warm until medical help arrives.
  6. If you see a person fainting, try to prevent a fall. Lay the person flat on the floor and raise the feet about 12 inches.
  7. If fainting is likely due to low blood sugar, give the person something sweet to eat or drink when they become conscious.

DO NOT    Return to top

When to Contact a Medical Professional    Return to top

Call 911 if the person is unconscious and:

Call 911 if the person regains consciousness but:

Prevention    Return to top

People with known medical conditions, such as diabetes, should always wear a medical alert tag or bracelet.

References    Return to top

Smith J, Seirafi J. Delirium and dementia. In: Marx J, ed. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 6th ed. Philadelphia, Pa: Mosby Elsevier; 2006: chap 102.

Kothari RU, Crocco TJ, Barsan WG. Stroke. In: Marx J, ed. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 6th ed. Philadelphia, Pa: Mosby Elsevier; 2006: chap 99.

Update Date: 10/6/2008

Updated 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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