Medically Induced Coma: Everything You Need to Know

Medically Reviewed By Seunggu Han, M.D.
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A medically induced coma uses medication to achieve a deep state of brain inactivity. It is a deep but reversible unconsciousness that doctors purposely induce to protect the brain from damage. A common name for medically induced coma is drug-induced coma, but this is often mistaken for comas caused by the inappropriate use of illegal drugs. It is also a term used for comas caused by a drug reaction or drug intoxication.

This article will define a medically induced coma, why and how it is done, potential risks, and recovery.

What is a medically induced coma?

young boy on a ventilator in a coma
Ariel Skelley/Getty Images

A medically induced coma is a deep sedation of the brain using anesthetics. The goal of a medically induced coma is to reach a level of sedation called “burst suppression.” In this state, the brain is completely quiet for several seconds, alternating with very short bursts of activity, as recorded by an EEG.

The period when the brain is quiet or suppressed gives it vital time to rest and heal. In a medical coma, the periods of suppression get longer as the level of anesthesia deepens.

General anesthesia is a type of medically induced coma, but the goals are different. The goal of general anesthesia is to keep the brain unaware of and unable to feel pain during a surgical procedure. General anesthesia and a medically induced coma can also differ in the level of consciousness.

Why is a medically induced coma performed?

Reasons for medically induced coma include:

  • traumatic brain injury accompanied by swelling and increase in intracranial pressure
  • stroke
  • status epilepticus, which is a seizure lasting longer than 5 minutes or a continuous seizure with loss of awareness
  • drug overdose

Traumatic brain injuries often result in a significant swelling of the brain. The swelling puts pressure on the brain, which reduces blood flow and oxygen supply, and can damage brain tissue.

Inducing a coma allows the brain to rest and decreases the brain’s activity and metabolic rate. Ultimately, this state helps decrease brain swelling and protects the brain from further damage.

A medically induced coma is not a common procedure. It is usually a last resort when other options for reducing brain swelling or seizure activity have failed. For brain swelling, doctors usually try medications, such as diuretics, first.

Who performs a medically induced coma?

An anesthesiologist will start a medically induced coma. An anesthesiologist is a physician who specializes in relieving pain and providing total medical care for patients before, during, and after surgery. These doctors also care for patients outside the surgery department in areas such as intensive care units (ICUs) and pain clinics.

Once the medically induced coma is underway, ICU staff will closely monitor brain activity and vital signs. Staff includes doctors, nurses, and other critical care healthcare professionals.

How is a medically induced coma performed?

Medically induced comas are ICU procedures. ICU doctors have the necessary equipment to support the airway and monitor heart rate, blood pressure, and breathing. The support and monitoring are necessary for the entire time someone is in a medically induced coma.

Induction

An anesthesiologist will give medication to induce the coma. Common induction agents include propofol and barbiturates, such as pentobarbital and thiopental. These are powerful anesthetics that will take the brain to a state of deep unconsciousness.

An EEG allows the doctor to monitor brain activity. Once the brain’s activity reaches the goal level, a machine will continue to deliver precise doses of anesthetic. ICU staff will continually monitor the EEG and adjust the dose as necessary to maintain the target brain activity level.

While the person is in a medically induced coma, they will be unresponsive.

Breathing and nutritional support

When someone is in an induced coma, they are on a ventilator. They will receive nutrients by IV — that is, through a vein. In addition to continuous EEG monitoring, the nursing staff will also monitor the patient’s heart and lung function.

Reversal

Once doctors decide it is safe, an anesthesiologist will reverse the process and bring the person out of the coma.

In most cases, medically induced comas are only necessary for a short period of time. To manage traumatic brain injury, doctors typically use propofol for only a couple of days. Neurologic outcomes do not support a longer period.

However, the doctor may bring the patient out of the coma every couple of days to monitor neurological function and seizure activity. If seizure activity resumes, they will restore the coma.

What does a normal EEG look like? Learn more here.

Frequently asked questions about medically induced comas

Why is a person put in a medically induced coma?

A person may be put in a medically induced coma in case of uncontrollable seizures, brain swelling, or an increase in intracranial pressure.

Is a medically induced coma good or bad?

A medically induced coma is good when it protects the patient from further brain damage due to injury or seizures. Doctors and nurses who induce comas have extensive training in administering coma-inducing medications and monitoring patients in a coma.

Without proper drug delivery, monitoring, and drug withdrawal, a medically induced coma can be dangerous.

Does a medically induced coma mean death?

No. A person in a medically induced coma is unconscious and does not react to external stimuli, such as light, sound, or touch. The brain may process stimuli to some degree, but the person cannot wake up to the stimuli, such as pain.

Can you breathe on your own in a medically induced coma?

No. After initial sedation, the doctor puts the patient on a ventilator and then induces deeper sedation.

What are the risks of a medically induced coma?

Complications that can occur from a medically induced coma include:

Reducing the risk of complications

It is not always possible to reduce the risk of complications with a medically induced coma. Moreover, it can be difficult to separate complications of a medically induced coma from complications of the brain injury itself.

Doctors use medically induced comas as a last resort when the benefit outweighs the possible risks.

What to expect afterward

When doctors see improvements in a person’s condition, they will bring them out of the medically induced coma. The process is the reverse of inducing it. Doctors gradually withdraw the drugs while monitoring brain activity and other vital signs.

How long will it take to recover?

The length of time it takes to recover from a medically induced coma depends on several factors. This includes the underlying brain injury and how long the coma lasted. In general, the longer the coma lasts, the more time it will take to regain functions.

However, according to ICUsteps, a registered charity organization for patients recovering from critical illness, “the length of time spent in an induced coma does not give information about what type of recovery the patient will make.”

Patients waking from a coma may show the following signs and symptoms:

  • agitation
  • anxiety
  • fear
  • amnesia
  • confusion
  • change in personality, such as a typically quiet person acting out and shouting
  • change in speech

These symptoms can be very alarming for the friends and family of a person coming out of a coma. ICUsteps indicates these symptoms may last minutes, weeks, or months, but will “pass in time.”

Is there pain after regaining consciousness?

A medically induced coma eliminates pain. However, the underlying brain injury and other treatments may involve pain and discomfort once consciousness returns.

Outlook

The ultimate effect on the patient depends on the extent of brain damage from the trauma, stroke, or seizures. It is possible to experience lingering disability due to the underlying brain trauma.

A person in a coma does not react to external stimuli, but the brain has some activity and may process sounds, smells, and touches. Interacting with the person and stimulating the senses during the coma may help the brain recover. With the doctor’s permission, you might try:

  • talking to a person in a coma about events, family, and friends
  • playing their favorite music
  • bringing in their favorite foods
  • holding their hand or offering light massage

Summary

A medically induced coma is a state of unconsciousness that doctors bring on by administering anesthetics and barbiturates, such as propofol and pentobarbital. These drugs slow blood flow to the brain and decrease brain activity.

In people with a high risk for additional brain damage due to swelling or continuous seizures, a medically induced coma is a lifesaving procedure. It helps reduce swelling and gives the brain time to heal.

Doctors may induce comas in people with traumatic brain injury, repetitive or long lasting seizures, stroke, or drug overdose. The length of time a person is in a coma and recovery time afterward varies. A medically induced coma may continue for 24­–48 hours at a time until swelling or seizures subside.

The short-term and long-term outlook for a person awakening from a medically induced coma depends on the underlying reason for the coma, the extent of brain damage, and other factors.

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Medical Reviewer: Seunggu Han, M.D.
Last Review Date: 2022 Mar 15
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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