Unconsciousness is an unresponsive state. A person who is unconscious may seem like they are sleeping, but may not respond to outside events, such as loud noises or being touched or shaken.
Fainting is a type of unconsciousness that comes on suddenly and may only last a few seconds. Unconsciousness can last for much longer, and a person's vital signs can change. Seek immediate medical attention if a person's pulse becomes weak, or they stop breathing.
What to do first when a person is unconscious
If a person is unconscious or unresponsive, call emergency medical services.
When someone appears to be unconscious or unresponsive, the first thing to do is ask them if they are okay in a loud voice; then gently shake them, unless they appear to have a spinal cord injury. If they do not respond, follow these steps in this order:
- check their airway is open without signs of blockage, such as labored breathing or high-pitched breath sounds
- look for signs they are breathing
- check for a pulse or heartbeat
Next, call or have someone else call the emergency medical services, which is 911 in the United States, if the person:
- has no pulse or only a weak pulse
- does not appear to be breathing
- does not respond or regain consciousness within 1 minute
- seems to be severely injured or is bleeding heavily
When speaking to emergency services on the phone, do not hang up until told to do so.
Check the person's wrists and neck to see if they are wearing a first aid tag, as this can give some indication of why they may have lost consciousness. Share the information on the tag with emergency services.
First aid steps
Before acting, it is essential to determine whether the unconscious person is breathing or not, as this will inform what to do next.
If the person is breathing
If the person is still conscious but seems dazed, ask them basic questions, such as what their name and birthday is or what the date is today.
Wrong answers or an inability to answer may mean they are experiencing a change in mental status. Share this information with emergency medical services.
If it appears the person may have a spinal injury, leave them as they are. Take measures to keep their neck supported and still.
If the person is breathing and it is unlikely they have a spinal injury, roll them into the recovery position on their side. Adjust the person's legs, so their hips and knees form right angles. Tilt their head gently back to be sure their airway is open.
If the person is not breathing
If an unconscious person is not breathing, it may be necessary to move them carefully onto their back, while protecting their neck, so that they can receive cardiopulmonary resuscitation (CPR).
Call 911 before administering CPR.
Signs, such as moving, coughing, or breathing are good signs. If these signs are not there, continue giving CPR until the emergency assistance arrives.
If the person is bleeding
If the unconscious person is bleeding heavily, locate the injury and place strong, direct pressure on the wounded area to slow the flow of blood. If possible, apply a tourniquet above the bleeding area to slow the bleeding until emergency services arrive. To apply a tourniquet, wrap a cord or bandage tightly around the affected limb.
How to perform CPR
Only trained individuals should perform the entire CPR procedure.
CPR is an emergency procedure used to assist someone when they stop breathing and have no pulse. It consists of giving chest compressions, which is the cardio part, and rescue breaths, which is the pulmonary part.
Only people with CPR training should perform the entire procedure. To reduce the chances of potential injury, anyone who has not had CPR training should only perform chest compressions in steps 1 to 7 in the instructions below and not the rescue breaths in steps 8 to 10. Chest compressions can still help circulate oxygen-rich to the body and brain.
Before beginning CPR, try to wake the person again by calling their name loudly and asking if they are okay.
If the person is still unresponsive, perform a head tilt to open the airway:
- Place one hand on their forehead and the fingers of your other hand under the tip of their chin.
- Then gently tilt their head back, which moves the tongue, so it does not block the airway.
If there is a suspicion of a spinal injury, perform a jaw thrust instead:
- Kneel near the top of the person's head with your hands on either side of the face.
- Gently lift the person's jaw with your fingertips without moving their neck.
When the person's airway is open, follow these steps to perform CPR:
1. Lay the person on their back on any flat, hard surface available. Protect their neck from large movements if it looks like they might have a spinal injury.
2. Kneel down next to their shoulders, so your torso is over their chest.
3. Put the palm and heel of your hand in the center of their chest.
4. Place your other hand directly on top of the first hand and interlock your fingers.
5. Keep your elbows straight, kneel up to bring your shoulders up over your hands for more strength in your upper body.
6. Using the weight and force from your upper body, push straight down on their chest, compressing the chest at least 2 – 2.4 inches for adults, then release the pressure. This is one compression.
7. Do sets of 30 compressions at the rate of 100–120 times per minute, which is about twice every second.
Only people with CPR training should follow the next steps:
8. Tilt the person's head back and lift their chin to maintain an open airway.
9. Pinch their nose and cover their open mouth with your open mouth, making an airtight seal.
10. Blow until you see their chest rise. This is one breath. Perform two breaths, letting the lungs relax and exhale in between breaths.
Continue with the pattern of 30 compressions and two breaths until the emergency services arrive.
This video demonstrates how to perform CPR on an unconscious person:
What not to do
There are also some things to avoid when administering first aid:
- Do not put a cushion under an unconscious person's head, as it may disrupt their breathing.
- Do not try to get them to sit up.
- Do not splash an unconscious person with water or slap them.
- Do not try to get them to drink water or other liquids.
- If there is something visible at the back of the person's throat or high in the throat that is blocking the airway, try to remove it by using one finger to sweep the mouth. Do not do a finger sweep or try to grab at anything lodged in the person's throat if it is not visible. This may cause it to become lodged deeper.
- If they are not breathing and they have an object lodged in the throat, continue performing chest compressions and checking to see if the object has dislodged.
- Do not leave an unconscious person unattended.
What are the signs of unconsciousness?
Some signs may suggest that a person is about to become unconscious, including:
- suddenly becoming unresponsive
- a blank or confused look on their face
- lightheadedness, dizziness, or trouble standing
- slurred or mumbled speech
- a rapid heartbeat
Causes of unconsciousness
A serious accident or injury can lead to unconsciousness.
Many circumstances can lead to unconsciousness. Major traumatic events or injuries can cause unconsciousness, such as
- serious accidents, such as car crashes
- taking a particularly heavy blow to the head or chest
- severe blood loss or internal bleeding
- alcohol or carbon monoxide poisoning
- intentional or accidental drug overdose
A sudden, temporary unconsciousness can also result from fainting, or syncope. Neurally mediated syncope (NMS) is the most common form of fainting. NMS is generally harmless and does not usually require medical treatment.
NMS happens when the brain fails to respond correctly to a trigger, such as seeing blood or something shocking or unpleasant. This response cuts the flow of oxygen to the brain, and the person passes out.
Some other causes of temporary unconsciousness include:
- low blood pressure
- low blood sugar
- heart problems, such as arrhythmia or cardiac syncope
- hyperventilating, which is very fast breathing
When to seek emergency help
Fainting or temporary loss of consciousness is not always a sign that the person needs medical assistance. However, contact emergency services immediately for any of the following signs or conditions:
- loss of bladder or bowel control
- having a seizure or fit
- not breathing
- no pulse
If the person regains consciousness, look out for other serious signs and symptoms, such as:
- not being able to speak or see correctly
- not being able to move their arms or legs
- having chest pain or an irregular heartbeat
These are serious signs, and the person should seek emergency medical care.
Complications of prolonged unconsciousness can be severe. Lack of oxygen to the brain may result in brain damage, and choking can lead to death if left untreated.
Emergency first aid may also cause complications. For instance, CPR can sometimes cause fractured ribs.
Administering first aid for an unconsciousness person is a good immediate step to help them, but it is crucial that they get the medical attention they need. Getting emergency attention sooner may mean fewer complications and an overall better outlook.