Coma

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What is a coma?

Coma is a state of decreased consciousness whereby a patient cannot react with the surrounding environment. The patient cannot be easily wakened when outside physical or auditory stimulation are applied. Patients may have different levels of unconsciousness and unresponsiveness depending upon how much or how little of the brain is functioning. Patients in coma do not voluntarily interact with their environment.

The inability to waken differentiates coma from sleep.

What is the Glasgow Coma Scale?

The Glasgow Coma Scale was developed to provide health-caregivers a simple way of measuring the depth of coma based upon observations of eye opening, speech, and movement. Patients in the deepest level of coma:

  • do not respond with any body movement to pain,
  • do not have any speech, and
  • do not open their eyes.

Those in lighter coma may offer some response to a verbal or painful stimulus, to the point they may even seem wake, yet meet the criteria of coma because they do not respond to their environment by initiating voluntary actions.

The Glasgow Coma Scale is used as part of the initial evaluation of a patient, but does not assist in making the diagnosis as to the cause of coma. Since it "scores" the level of coma, the Glasgow Coma Scale can be used as a standard method for any health care professional to assess change in the patient's mental status over time.

The best use of the Glasgow Coma Scale is to allow caregivers of different clinical skills and training to consistently assess a patient over longer periods of time in order to determine whether the patient is improving, deteriorating, or remaining the same. In the initial care of a comatose patient, chronologically, there may be first responders, emergency medical technicians (EMTs), paramedics, nurses, emergency physicians, neurologists, and neurosurgeons, all evaluating the same patient in different places at different times. The Glasgow Coma Scale allows a standard assessment that can be shared.

Glasgow Coma Scale
Eye Opening
Spontaneous 4
To loud voice 3
To pain 2
None 1
Verbal Response
Oriented 5
Confused, Disoriented 4
Inappropriate words 3
Incomprehensible words 2
None 1
Motor Response
Obeys commands 6
Localizes pain 5
Withdraws from pain 4
Abnormal flexion posturing 3
Extensor posturing 2
None 1

A fully awake patient has a Glasgow  Coma Score of 15. A person who is dead has a Glasgow Coma Scale of 3 (there is no lower score).

Medically Reviewed by a Doctor on 11/15/2013

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Coma - Causes Question: What caused your coma, or that of someone you know?
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