A medically induced coma is profound sedation done with the use of medications, such as those used for general anesthesia, to help patients who are in critical condition recover from events like a stroke, brain injury, heart attack, or respiratory illnesses like severe pneumonia.
A person in an induced coma may wake up after several hours or days, either when they have recovered or a doctor recommends it. A medically induced coma is different from a coma caused by illness, as the latter cannot be predicted and is outside the doctor's control.
Medically induced comas are typically performed in the ICU with machines to support breathing and continuous monitoring of vital signs to help avoid complications like respiratory or cardiac arrest and reactions to medications.
Indications for use
A medically induced coma is a type of profound sedation caused by medications and may be necessary when a patient is in critical condition from events like:
- Head trauma caused by an accident or fall;
- Epileptic seizures that do not improve with medications;
- Serious heart disease due to heart attack, heart failure, or cardiac arrhythmias;
- Severe respiratory failure caused by pneumonia, emphysema, or cancer;
- Serious neurological conditions, such as stroke, meningitis, or a brain tumor;
- Post-op from a complicated surgery, such as brain surgery, heart surgery, or trauma surgery following a serious accident;
- Pain that does not improve with medications, such as large burns or advanced cancer.
In these cases, a medically induced coma is used so that the brain and the body have a better chance of recovery, helping the body save energy by not being active. An induced coma also allows the patient to avoid feeling pain and discomfort caused by their condition.
In the case of severe lung disease, like pneumonia, sedation is used in conjunction with mechanical ventilation to improve oxygenation.
Duration of treatment
A medically induced coma is done using sedatives like midazolam or propofol administered in controlled doses and injected directly into a vein through an IV, typically in the ICU. The effects may last hours, days, or weeks. In time, a doctor may interrupt the coma because the patient's status has improved or to perform an evaluation of the patient's condition.
Can a person in a coma hear you?
People in a coma are not conscious and cannot feel, move, or hear. There are, however, various levels of sedation that depend on the dose of the medications used to induce a coma. People under lighter sedation may be able to hear, move, or interact as if they were very drowsy.
How should I talk to a person in a coma?
When visiting a family member or friend who is in a medically induced coma it is important to interact with them, as some people report remembering situations that happened while they were in a coma. While visiting, it is a good idea to:
- Tell the person who you are;
- Talk about things like you normally would, such as work and day-to-day life. Tell jokes or talk about how important the person is to you;
- Show love and support by holding their hand, for example.
Some studies show it is possible to help people recover from a coma by stimulating the senses of touch, hearing, sight, and smell. Periods of stimulation should be brief and tailored to the individual patient.
Recovery and expectations
Recovery from a medically induced coma will vary depending on how quickly the medication is metabolized by the body.
Some people may begin to wake up as soon as sedation is withdrawn. Others will remain unconscious or enter into a vegetative state, a condition in which a person appears to be awake but is unaware of what is happening around them.
Whether a person survives or has long term sequelae (side effects) following a medically induced coma depends on the type and severity of their condition as well as their overall health status. Age, nutritional status, and the use of any medications also play a role.
Some people may recover from these conditions gradually over time, while others may not improve at all.
Potential risks
Complications may occur from the medications used to induce a coma, which are similar to those used in general anesthesia. Potential risks include:
- Allergic reactions to the active ingredient in the medication;
- Decreased heart rate;
- Respiratory arrest.
These complications are avoided with continuous monitoring of a patient's vital signs and frequent evaluations by the medical team in the ICU. For people in critical condition, the risk of sedation is lower than the risks of the underlying condition.