How Healthcare Providers Define Whether You're Really Unconscious (2024)

When a person is unaware of their surroundings and unable to respond, this is described as being unconscious. Unconsciousness is a medical emergency, and it is often a sign of a serious health issue that could result in death or permanent disability.

If you encounter a person who is unconscious, call for urgent medical attention and try to provide as much information to emergency medical responders as possible. There are many causes of unconsciousness, and the medical team will work on identifying the cause while treatment is started.

What Is Unconsciousness?

Consciousness is a spectrum. Being fully awake, alert, and oriented to your surroundings is the most common and normal state of consciousness. Altered levels of consciousness include normal stages of sleep, as well as states of diminished awareness due to illness or medication.

Unconsciousness includes:

• General anesthesia, a medically induced state of unconsciousness that can be reversed when it's time to wake up after surgery
• Being unresponsive and unarousable to smells, touch, noises, or pain due to illness
• Coma, unconsciousness that has lasted for a long period of time

Signs or Symptoms

During a period of unconsciousness, a person is not arousable, and will not respond or have any control of themselves.

Unconsciousness can occur suddenly, or it may develop gradually, depending on the cause. A person might feel sick, dizzy, short of breath, have chest pain, or might feel lethargic or faint before becoming unconscious. Lethargy is a state of being awake, but with diminished alertness and diminished ability to respond.

After recovering from unconsciousness, it usually takes hours, days, or longer to regain full awareness and ability to respond.

Symptoms of unconsciousness include:

• Appearing as if asleep
• Unarousable and unresponsive
• Not deliberately moving the body
• May have involuntary physical movements, such as jerking, spasms, or seizures
• Might vomit
• Incontinent of urine and stool
• Sometimes unable to urinate or have a bowel movement, leading to retention (which can be dangerous)
• Might breathe on their own or have impaired breathing

Associated symptoms are typically related to the cause. For example, a person who is unconscious due to sepsis or septicemia (severe infection and consequences of infection), could also have a fever, skin changes, and organ failure.

Causes

Consciousness is a function of the brain. An altered level of consciousness is a sign that a medical condition has affected brain function. Many different medical conditions can affect consciousness.

For example, cardiac arrest leads to a sudden loss of consciousness because blood stops flowing to the brain. In cardiac arrest, the brain isn't the problem—the heart is. However, the loss of consciousness is the indicator of the problem.

Causes of altered levels of consciousness can be summarized with the mnemonic AEIOU TIPS:

• A - Alcohol: The amount of alcohol that can cause a person to lose consciousness varies from one person to another. For example, a person who takes medications that interact with alcohol or who has liver disease can become unconscious after drinking a relatively small amount of alcohol.
• E - Epilepsy or exposure (heat stroke, hypothermia)
• I - Insulin (diabetic emergency)
• O - Overdose or oxygen deficiency: A recreational drug or medication overdose can cause loss of consciousness. Oxygen deficiency can occur due to heart or lung disease.
• U - Uremia (toxins due to kidney failure)
• T - Trauma (shock or head injury)
• I - Infection
• P - Poisoning; This can occur due to ingesting toxins (such as a chemical cleaner) or as a result of organ failure, which can cause toxins to build up in the body.
• S - Stroke

When a person is unconscious, the brain is functional. Unconsciousness is not the same as brain death. Brain death is a condition in which the brain is not functioning, and it can occur when the same medical issues that cause unconsciousness lead to severe and permanent brain damage.

First Aid

If someone is unconscious, you can take steps to assist while you are waiting for professional medical help to arrive.

Things you can do include:

• Check if they are breathing
• Try to feel their pulse
• Administer CPR if they need it and you know how to do it
• Use the Heimlich maneuver if they need it and you know how to do it
• Cover them with a warm blanket if the temperature is too cold
• Place an ice pack on them if the temperature is too hot

What to Avoid

• Do not place anything in their mouth
• Do not administer medication
• Do not move their neck or back—this can cause permanent paralysis if the spine is injured

When to Seek Medical Care

If you are with someone who becomes suddenly unconscious and does not immediately recover, call 911.

If you have recovered from an episode of unconsciousness, you should see your healthcare provider to determine whether you need additional tests or treatments to find the cause and prevent a recurrence.

Sometimes altered levels of consciousness, such as lethargy, can occur due to fluctuation of a chronic condition. For example, a person can have impaired consciousness due to very high or low blood sugar levels with diabetes. And a seizure can cause a person to be unconscious during the post-ictal state.

Treatment

Unconsciousness is treatable. Immediate treatment can result in improved awareness, and it can also prevent death or lasting health effects. Treatment involves urgent care to manage the immediate problem, as well as long-term care.

Treatment can include:

• Non-invasive oxygen administration
• Intravenous fluids
• Medication to treat an acute heart condition
• Cardioversion, in which electric shocks are administered on the chest
• Medication to stop a seizure
• Mechanical breathing support
• Intubation

Many of these treatments can be started by first responders on the way to the emergency department.

Frequently Asked Questions (FAQs)

What causes unconsciousness?

Any illness or condition that severely affects brain function can cause unconsciousness. This can include head trauma, heart disease, breathing problems, infections, drugs, and more.

What is unconsciousness?

Unconsciousness is a lack of awareness and a lack of responsiveness.

How do you treat unconsciousness?

You should call for emergency medical help, and in the meantime, you can administer CPR or other first aid if it is needed and if you know how to do it.

What are the stages of unconsciousness?

There are several definitions of stages of consciousness. Full alertness is a state of normal consciousness. Lethargy is an impaired state of consciousness. Unconsciousness is a severely impaired state of consciousness. Brain death is a state in which the brain is not functioning.

A Word From Verywell

Unconsciousness is a sign of a serious medical problem that could cause death or disability. There are emergency protocols that first responders use when encountering a person who is unconscious. Calling for help is your most important role as a companion or bystander.