Unconsciousness occurs when a person is suddenly unable to respond to stimuli and appears to be asleep. A person may be unconscious for a few seconds (as is the case with fainting) or for longer periods of time.
People who become unconscious do not respond to loud sounds or shaking. They may even stop breathing or their pulse may become faint. This calls for immediate emergency attention. The sooner the person receives emergency first aid, the better his or her outlook will be.
Unconsciousness is when a person suddenly becomes unresponsive. He or she will not be able to communicate and won’t respond to stimulation. Unconsciousness can be brought on by a major illness or injury, or complications from drug use or alcohol abuse.
Common causes of unconsciousness include:
- a car accident
- severe blood loss
- a blow to the chest or head
- a drug overdose
- alcohol poisoning
A person may become temporarily unconscious (faint) when sudden changes occur within the body. Common causes of temporary unconsciousness include:
- low blood sugar
- low blood pressure
- syncope (loss of consciousness when the brain is deprived of blood flow)
- problems with the heart’s rhythm
- neurologic syncope (caused by a seizure, stroke, or transient ischemic attack)
Symptoms that may indicate that unconsciousness is about to occur include:
- sudden inability to respond
- slurred speech
- a rapid heartbeat
- dizziness or lightheadedness
If you see a person who has become unconscious, take these steps:
- Check to see if the person is breathing. If he or she is breathing, position the person on his or her back.
- Raise the person’s legs at least 12 inches above the ground.
- Loosen any restrictive clothing or belts. If the person does not regain consciousness within one minute, call 911.
- Check the person’s airway to make sure it is not obstructed.
- Check again to see if the person is breathing, coughing, or moving. These are signs of positive circulation. If these signs are absent, start CPR until emergency personnel arrive.
CPR, or cardiopulmonary resuscitation, is used in cases when a person stops breathing or his or her heart stops beating.
If a person becomes unconscious or stops breathing, call 9-1-1 or ask someone else to. Before beginning CPR, ask loudly, “Are you OK?” If the person does not respond, begin CPR.
- Lay the person on his or her back on a firm surface.
- Kneel next to the person’s neck and shoulders.
- Place the heel of your hand over the center of the person’s chest. Put your other hand directly over the first one and interlace your fingers. Make sure that your elbows are straight and move your shoulders up above your hands.
- Using your upper body weight, push straight down on the person’s chest at least 1.5 inches for children or 2 inches for adults. Then release the pressure. Repeat this procedure again up to 100 times per minute. These are called chest compressions.
To minimize potential injuries, only those who are trained in CPR are encouraged to perform rescue breathing. If you have not been trained, perform hands-only CPR by providing chest compressions until medical help arrives.
If you are trained in CPR, tilt the person’s head back and lift the chin to open up the airway.
- Pinch the person’s nose closed and cover his or her mouth with yours, creating an airtight seal.
- Give two, one-second breaths and watch for the person’s chest to rise.
- Continue alternating between compressions and breaths–30 compressions and two breaths–until help arrives or there are signs of movement.
If unconsciousness is caused by low blood pressure, a doctor will administer medication by injection to increase blood pressure. If a low blood sugar level has caused the person to become unconscious, he or she may be given something sweet to eat or a glucose injection.
Injuries that may have caused the person to become unconscious will be corrected through surgery or by other means in a hospital.
Potential complications of being unconscious for a long period of time include:
- brain damage
If you received CPR while unconscious, you may have broken or fractured ribs from the chest compressions. Your doctor will X-ray your chest and treat any fractures or broken ribs before you leave the hospital.
Choking can also occur during a period of unconsciousness. Your airway may become blocked by food or liquid. This is particularly dangerous and could lead to death if left untreated.
Your outlook will depend on what caused you to lose consciousness. However, the sooner you receive emergency treatment, the better your outlook will be.