Information About Coma

What is coma?

Coma is a prolonged state of unconsciousness in which the patient is not aware of self or the environment. Coma seems a lot like sleep because the patient’s eyes are usually closed and there often is no response to sounds. Unlike sleep, coma is neither easily reversed nor is there normal uptake of oxygen into the brain.

There are different levels of coma. Some patients may react reflexively to touch or pain. They may even groan and move about. Other patients, whose coma is not as deep, may show signs that they understand by squeezing a hand in response to a familiar voice or sound. Medical professionals recommend that family members interact with comatose patients as if they can understand because no one knows for certain what they can understand.

The length of coma varies among patients and can last from a few days to several months. Patients who have been comatose for extended periods of time may open their eyes and appear to be looking around their room. Upon closer study it becomes apparent that their eyes are not interacting with their environment. Emergence from coma is most often a gradual process of increased responsiveness and awareness. The Rancho Los Amigos Cognitive Scale is used to monitor a patient’s level of consciousness.

What is the Glasgow Coma Score?

Emergency personnel use this test to evaluate a patient’s state of altered consciousness immediately after trauma. The states measured range from normal to mild confusion to deep coma. Scores range from 3 to 15. Patients with scores of 3 to 8 are considered to have suffered severe injury; patients with scores of 9-12 are considered to have suffered moderate injury; and patients with scores of 13-15 are considered to have suffered mild injuries. The scale is often used as a predictor of survival. Patients with scores in the severe range often do not survive whereas almost all patients with scores in the mild range will survive.

The scale is at best a gross predictor of outcome because a patient may have much different scores a minute after the trauma than five minutes or an hour later. Knowing when a score was obtained and how quickly it improved or deteriorated is yet another factor in determining outcome. The scale is of limited use in predicting which patients will be able to return to suitable employment. Most patients with scores of 13 to 15 will do quite well, while a few will find that their life has been forever changed. The score is calculated by determining a patient’s responses in three areas: eye opening, verbal response and best motor response. See the chart at right for information.

 Eye openingOpens eyes on own4
To touch or loud voice3
To pain3
 Verbal responseOriented5
 Best motor responseFollows simple commands6
Localizes pain5
Flexes to pain3
Extends to pain2
No motor response to pain1

What is the Rancho Los Amigos Cognitive Scale?

This scale is used to track the improvement of a patient who has suffered traumatic brain injury. It is a very broad measure of cognitive functioning and uses psychosocial behavior as its criteria. It can be used to measure the effectiveness of various treatments. Doctors and insurance companies often use the scale to evaluate a patient’s potential for rehabilitation. The scale can be an effective tool for making planning and placement decisions. It generally can distinguish those patients who will be able to return to competitive employment from those who will be able to handle only supported work. It is not very effective in determining which patients, among those who return to competitive work, will have lowered vocational potential. See the chart at the right to see the eight levels of the scale.


Level INo response.
Level IIGeneralized response: Inconsistent, non-purposeful, nonspecific reactions to stimuli.
Level IIILocalized response: Inconsistent reaction directly related to type of stimulus presented.
Level IVConfused & Agitated: Alert, very active, aggressive, or bizarre behavior; performs motor activities but behavior is non-purposeful; extremely short attention span.
Level VConfused & Inappropriate but not Agitated: Gross attention to environment; highly distractible and requires continual redirection; difficulty learning new tasks; agitated by too much stimulation; may engage in social conversation but with inappropriate verbalizations.
Level VIConfused and Appropriate: Behavior is goal directed; depends on external input for direction; follows simple directions; responses are appropriate to the situation with incorrect responses due to memory difficulties.
Level VIIAutomatic and Appropriate: Correct routine responses that are robot-like; appears oriented to setting, but insight, judgment, and problem solving are poor.
Level VIIIPurposeful and Appropriate.


Contact Steve Gerdes