A coma looks like deep sleep because the person is unconscious with their eyes closed, but it's fundamentally different: unlike sleep, you cannot wake someone from a coma with stimulation like sound or pain, as it involves severe brain dysfunction, not rest. A sleeping brain cycles through stages, processes some stimuli, and has distinct brain activity, while a comatose brain shows much lower energy use, lacks normal sleep cycles (like REM), and cannot initiate voluntary actions, requiring intensive medical care.
The person's eyes may be closed, and they'll appear to be unresponsive to their environment. They may not respond to sound or pain, or be able to communicate or move voluntarily. Someone in a coma may also have very reduced basic reflexes, like coughing and swallowing.
Usually, a coma does not last more than a few weeks. Sometimes, however, a person stays in a coma for a long time — even years — and will be able to do very little except breathe on his or her own. Most people do come out of comas. Some of them are able to return to the normal lives they had before they got sick.
Comatose patients do not seem to hear or respond. Speaking may not affect their clinical outcome; time spent with them takes time away from other, more "viable" patients. Comatose patients may, however, hear; many have normal brain-stem auditory evoked responses and normal physiologic responses to auditory stimuli.
Spontaneous movements may occur, and the eyes may open in response to external stimuli. Individuals may even occasionally grimace, cry, or laugh.
When Edwarda O'Bara died on 21 November 2012, she had survived 15,663 days (about 42 years) in a coma. Born in 1953, in Miami, Florida, O'Bara suffered a childhood history of diabetes, which she successfully managed with insulin.
Being in a coma means you're not conscious, so you don't know you're in a coma. You don't show any signs of awareness of the world around you, and you can't react to your environment or your body's needs. Depending on the depth of the coma, you may still have some reflex responses. But these vary from case to case.
Whether they dream or not probably depends on the cause of the coma. If the visual cortex is badly damaged, visual dreams will be lost; if the auditory cortex is destroyed, then they will be unable to hear dreamed voices.
During the later stages of the disease, if the patient cannot speak at all, carers can still talk to them and communicate with gentle touch like hand-holding. If you rely on non-verbal communication, remember: • Physical contact, like an arm around the shoulder or hand holding, can be comforting.
Stage 1: Unresponsiveness
During the unresponsive stage, a patient typically does not respond consistently. The unresponsive stage is referred to as a coma. Patients in the unresponsive stage may have reflexive responses and random movements for no specific reason.
Comas can last from several days to, in particularly extreme cases, years. Some patients eventually gradually come out of the coma, some progress to a vegetative state or a minimally conscious state, and others die.
Causes
Coma is a state of consciousness that is similar to deep sleep, except no amount of external stimuli (such as sounds or sensations) can prompt the brain to become awake and alert.
Someone in a coma will also have very reduced basic reflexes such as coughing and swallowing. They may be able to breathe on their own, although some people require a machine to help them breathe. Over time, the person may start to gradually regain consciousness and become more aware.
Waking a person from a coma is so notoriously difficult that it's often added to the very definition of the state. But now, thanks to a new map of the parts of the brain responsible for wakefulness, neuroscientists might have figured out how to arouse at least some unconscious patients.
A coma stimulation programme (sometimes called a coma arousal programme) is an approach based on stimulating the unconscious person's senses of hearing, touch, smell, taste and vision individually in order to help their recovery.
Speak soothing words
An unresponsive and breathing person has normal, regular breathing, but does not respond to any sound or touch from another person. A person may become unresponsive due to an injury (e.g., hitting their head) or a medical condition (e.g., diabetic emergency) that may indicate a greater danger to their health.
Coma symptoms
Emerging evidence suggests the unconscious can experience many of the things that conscious people do.
Sleep is many things, but coma is not one of them.
Music stimulation is considered to be a valuable form of intervention for people with severe brain injuries and prolonged disorders of consciousness (i.e., unresponsive wakefulness/vegetative state or minimally conscious state).
There is no rule about how long a person can stay on life support. People getting life support may continue to use it until they either recover or their condition worsens. In some cases, it's possible to recover after days or weeks of life support, and the person can stop the treatments.
Patients with hidden consciousness due to a brain injury appear unresponsive while in a coma or vegetative state, but have brain activation to motor commands similar to conscious patients, according to Jan Claassen, M.D., FNCS, chief of critical care and hospitalist neurology at NewYork-Presbyterian and Columbia.