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Coma / Vegetative State

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“I had not cried in his room. I believed he could hear me, or at least sense what I was feeling … I told him we would be there when he woke up. That he should rest as long as he needed to heal. That he would be fine. Ryan would be fine because children don’t die and because he is Ryan … My eyes looked past the tube clamped to his mouth to keep him breathing, the hard plastic collar around his neck, the gauze turban, the wires snaking from his arms, chest, and skull into various beeping, blinking machines,” writes Joan Ryan about her son who sustained a brain injury while skateboarding — without a helmet.

Ryan was in a coma for several weeks.

What is a coma?
A coma is a profound or deep state of unconsciousness (consciousness being the awareness of the self and the environment). People in a state of coma are alive but unable to move or respond to their environment. Coma may occur as a complication of an underlying illness or as a result of an injury, like a brain injury.

Characteristics of coma include:

• No eye-opening
• Unable to follow instructions
• No speech or other forms of communication
• No purposeful movement

What is a persistent vegetative state?
A person in a coma may experience some improvement and transition into what is termed a “vegetative state.” The difference between a coma and a vegetative state is that a person in a deep coma usually requires hospital care, while a person in a vegetative state may be released to the family for home care. The individual in the vegetative state has a lot more lower-brain function (automatic functions like breathing, heart-rate regulation, and sleep), and a bit more upper brain-stem function (like eye opening or making sounds) than a person in deep coma.

Characteristics of the vegetative state include:

• Return of a sleep-wake cycle with periods of eye opening and eye closing
• May moan or make other sounds especially when tight muscles are stretched
• May cry or smile or make other facial expressions without apparent cause
• May briefly move eyes toward persons or objects
• May react to a loud sound with a startle
• Unable to follow instructions
• No speech or other forms of communication
• No purposeful movement

Measuring the depth of a coma
There are a few ways to measure the depth of a coma, but the most commonly used scale is called the Glasgow Coma Scale (GCS). The GCS rates the following functions:

• Eye opening
• Motor response
• Verbal response

Here are what GCS numbers or “scores” reflect:

• 3 – the deepest level of coma; total unresponsiveness
• 3-8 – severe injury
• 9 – not in a coma, but not fully alert
• 9-12 – moderate injury
• 13-15 – mild brain injury, or loss of consciousness for fewer than 20 minutes
• 15 – full consciousness

Secondary injury
Sometimes what’s called a secondary injury can make being in a coma or vegetative state even more dire. These secondary injuries can include infections, pneumonia, and bedsores. People emerging from coma can also be threatened by lack of proper balanced nutrition, contractures (permanent muscular contractions), and deformities of the bones, joints, and muscles.

Long-term outcomes
There are not exact numbers of how many people emerge from a coma or how many people will die while in a coma. There is research that shows that the overwhelming majority of patients emerge from deep comas within weeks after a brain injury.

But every brain injury — and person — is unique and sometimes even the doctors are surprised by a patient’s recovery. Rather than emphasizing complete recovery, treatment aims to improve function, prevent further injury, and rehabilitate individuals and their families physically and emotionally.