Coma

A coma is a state of unconsciousness. The person doesn't respond to anything around them and cannot be woken.

It can follow an injury to the brain, such as a severe head injury or a stroke. Several other conditions can also cause a coma.

Sometimes a patient is placed in a coma on purpose while in the intensive care unit (ICU), as part of their treatment. This is called an "induced coma". It helps the patient cope with other ICU procedures, like being on a ventilator. Doctors bring on this type of coma using certain types of anaesthetic drugs. A coma that isn't induced by medicine happens because of an injury to the brain.

A person in a coma is unconscious and has very little brain activity. They're alive, but you can't wake them, and they show no signs of being aware.

Their eyes may be closed, and they seem not to react to what's going on around them. They may not respond to sound or pain, and they can't communicate or move on purpose.

Basic reflexes, like coughing and swallowing, may also be very weak. Some people in a coma can breathe on their own. Others need a machine (a ventilator) and a breathing tube to keep the airway open.

As time passes, a person in a coma may slowly start to regain consciousness and become more aware. Some people do wake up, and the time they spend in a coma can vary from days to months. Other patients may never regain consciousness or wake up.

Doctors check how conscious a person in a coma is by using a tool called the Glasgow Coma Scale. They keep checking it all the time, looking for any sign that the person is getting better or worse. The scale looks at 3 things:

• eye opening
• verbal response to a command
• voluntary movements in response to a command

At first, a person in a coma will normally be looked after in an ICU. Their treatment will include:

• supporting their bodily functions (like breathing)
• treating the underlying cause of the coma

Later on, hospital staff give supportive treatment on a hospital ward. This can involve:

• providing nutrition (things like vitamins, protein and water that everyone needs to survive)
• trying to prevent infections
• preventing bedsores by moving the person
• gently exercising their joints to stop them becoming tight

If someone stays in a coma for a long time, they may have a tracheostomy put in to keep their airway open. This makes it easier to give better mouth care (for example, toothbrushing), and it means the person can be moved to a long-term ward for supportive care.

What it's like to be in a coma differs from person to person. Some people feel they can remember things that happened around them while they were in a coma. Others remember nothing at all.

Some people have false memories from that time. They can also have dreams and flashbacks after they've recovered.

A number of people have said they felt enormous reassurance from having a loved one with them as they came out of a coma.

If you're visiting someone who is in a coma, it can help to:

• announce who you are when you arrive
• talk to the patient as you normally would
• be aware that everything you say in front of them might be heard
• show them your love and support, because sitting and holding their hand or stroking their skin can be a great comfort

If a loved one is in a coma, it can help to keep a diary where you write down things like news stories, family events and information about their care. Many ICUs already do this, so you can ask the staff about keeping a diary when you visit.

A coma can go on for a long time. During that time, the person might:

• start to wake up slowly and gain consciousness
• move into a vegetative state (where the person is awake but shows no sign of being aware of their surroundings or of themselves)
• move into a minimally conscious state

Some people recover from these states gradually. Others may not improve for years, if at all.

People who do wake up from a coma usually come round slowly. At the start they may be very agitated and confused.

Some people make a full recovery and are not affected by the coma at all. Others are left with disabilities because of the damage to their brain. They may need physiotherapy, occupational therapy, psychological assessment and support while they recover. They may also need care for the rest of their lives.

The chance of fully recovering from a coma depends on:

• how severe the brain injury is
• what caused the brain injury
• the person's age
• how long they've been in a coma
• how physically fit they were before the coma

No one can accurately predict how long a coma will last, whether the person will recover, or whether they'll have any long-term problems.