Neuropsychology and Rehabilitation Psychology Division Department of Physical Medicine and Rehabilitation.

Coma and the Vegetative State

My mother has been comatose for 3 months and remains unresponsive. Although I have seen her blink her eyes and move her fingers when I talk to her, the doctors says these are random, involuntary movements. A friend of mine suggested that I place my mother in a coma stimulation program. What is coma stimulation, and how can a coma stimulation program help?

Your question presents some interesting problems related not only to the treatment of persons following severe brain injury, but also to some of the common problems with misdiagnosis of neurologic conditions after severe brain injury. Personally, I think it would be highly unlikely that your mother is truly comatose three months after her initial injury. Specifically, true coma generally does not last for more than three to four weeks. Typically, after this, one of three things occurs: the person either dies, transitions into a so-called vegetative state or regains some level of consciousness. The fact that you report that you have seen your mother blink her eyes, suggests that her eyes are open at times which is not congruent with a comatose state. If there is any awareness evident, based on your observations of interactions that your mother has with other professionals or with you, then she is neither comatose or vegetative but, clearly, conscious even though she may be severely disabled.

A vegetative state is a condition that can be seen following trauma that simply involves the person being arousable but unaware. That is , they have sleep/wake cycles and periods where their eyes are open as well as closed, but remain cognitively unaware, either internally or externally, of what is going on. In a comatose state, however, there is neither arousal or awareness. Eyes, as a rule, remain closed at all times.

The general approach to patients at the severe end of the functional spectrum following brain injury is to provide aggressive neuromedical and rehabilitative care in an attempt to facilitate emergence from these compromised levels of neurologic function, as well as to minimize and/or avoid complications associated with these states. "Coma stimulation program" used to be a very common phrase used by health care providers in the field of brain injury rehabilitation to describe the therapeutic efforts made at treating patients who were vegetative or in a minimally conscious state. This term has fairly much fallen out of favor due to several factors. Firstly, most practitioners who have been involved in treatment of persons with severe brain injury have not found this technique to be beneficial in terms of altering either the rate or eventual plateau of neurologic recovery following severe brain injury. Secondly, there are many other factors that need to be looked at in the overall treatment programs for such individuals, with sensory stimulation really being an optional therapeutic modality that, at least based on present data, has not been demonstrated to be effective in the manner in which it once was so strongly lobbied for. Certainly, it is important to provide ongoing objective assessments of the person’s neurologic level of function. "Coma Stimulation" can certainly aid in this area. It is critical to understand, however, what it can and cannot do for both clinicians as well as family members.

There are many more important neurologic, medical, and rehabilitative interventions that one should make sure are being administered to a family member following any severe brain injury that leaves them comatose, vegetative or minimally conscious. Such interventions include removal of all sedating medications (as possible); making sure that the individual has no treatable medical and/or neurosurgical complications such as epilepsy or communicating hydrocephalus; treating patients, particularly those in a minimally conscious state, with medications to improve arousal and/or slowed motor responses (so-called bradykinesia). Caregivers must also have an eye to good maintenance care aimed at maintaining skin integrity, range of motion, and optimal organ system function. Only through a concerted team effort can such individuals really be optimally cared for and their potential for further improvement, without concurrent morbidity, augmented.

How does the duration of a coma affect a patient’s recovery and prognosis? For example, does a shorter coma mean there is less brain damage, thus recovery will be quicker and stinger? Does a longer coma mean more there is more severe brain damage and a poorer prognosis?

Typically, coma is associated with more severe diffuse axonal shear injury although there are cases of more localized brain injury that may result in coma and, at least in cases where the underlying brain damage is felt to be mainly diffuse in nature, one can conclude fairly reliably that the longer the duration of coma, the more severe the brain injury and the poorer the prognosis. The duration of coma, assuming it is neurologically based and not due to chemically/artificially induced coma, is highly correlated with the overall extent of brain injury as well as the long-term neurologic/functional prognosis. It should be noted, however, that of the more important prognostic markers, the duration of coma is certainly not the most important from an overall assessment standpoint. The duration of post-traumatic amnesia (day-to-day ability to remember things) has been shown to be the most sensitive prognostic indicator for long-term functional outcome relative to other early prognostic factors.

I have heard the terms vegetative and vegetable referring to persons in a non-responsive state following severe brain trauma. Are these actual medical terms, and if so, what do they mean?

Thanks for your question regarding vegetative and vegetable in reference to persons in a non-responsive state following severe brain trauma. The term vegetative state was first coined in 1972 by Drs. Jennett and Plum. The term was meant simply to reflect a state in which there was return of so-called vegetative function, such as normalization of sleep/wake cycles among other basic bodily functions. This was described as a transition state between coma, where there is no arousal and no awareness, to some level of consciousness in which there was both arousal and at least some degree of awareness. The vegetative state, per se, is associated with arousal in the absence of awareness. That is, patients who are in a vegetative state of sleep/wake cycles generally are not dependent upon external mechanical life support to sustain basic life processes. As a rule, after a severe brain injury, a patient progresses through stages of emergence with coma being the lowest neurologic level of function, transitioning subsequently into a "vegetative state," and from there progressing to consciousness. Often times this term has been confused with the term "vegetable." The term never was meant to imply anything pejorative regarding the patient and/or his prognoses. Many patients following severe brain injury who have reasonably good to even good outcomes make transitions through a vegetative state that lasts for some period of time. Certainly, there are those patients who remain in a vegetative state and never emer_e from the state, although these numbers are extremely small, e.g., probably less than 3% of all persons with severe brain injury. There never has been to my knowledge a "medical term" that labeled anyone as a "vegetable." This latter type of language is certainly pejorative. Because of the potential confusion of the terms "vegetative" with "vegetable" some people have advocated that an alternative phrase to "vegetative state" be developed. Because vegetative state is so entrenched in the neurologic and neuromedical literature, many believe that such an effort may be in vain and the more logical route would be to simply better educate professionals as well as lay people regarding the true meaning of the phrase.

Does someone in a vegetative state ever regain consciousness or wake up?

Patients who are in a vegetative state may or may not regain consciousness. Based on newer terminology advocated by both the multisociety task force as well as, more recently, the Aspen workgroup, persons who sustain trauma and remain vegetative for a year or more can be said to be "in a permanently vegetative state." Such individuals, at least by probability, are not expected to emerge from a vegetative state; however, it must be understood that one can never totally rule out the possibility of emergence. Specifically, even though the term "permanent" vegetative state has been advocated for, this can never be said with 100% certainty, and there have been isolated reports (not all of which have had adequate medical documentation) of persons emerging from vegetative states beyond "permanency." As a rule, however, most individuals who enter into a vegetative state following trauma as opposed to degenerative neurologic conditions such as Alzheimer’s disease will (assuming that they live) emerge from a vegetative state at some point post-injury. The longer an individual is vegetative, inherent in the implicit degree of brain damage that has occurred, the more likely it is that he will have a more significant rather than less significant level of neurologic impairment upon emergence and the greater degree of disability it portends for the long-term outcome of that individual.

My brother is comatose. Although I've seen it happen all the time in movies, I've been told that comatose people do not simply wake up one day and feel like their old selves. What are the levels or stages of coma, and how long does it take to fully wake up?

The Levels of Cognitive Functioning Scale, which was developed by brain injury treatment staff at the Rancho Los Amigos Hospital in Downey, California, is a tool for describing a patient's behavior after a brain injury. The scale is applicable in the first weeks following the injury, during rehabilitation. The time it will take for a patient to progress through the levels of functioning cannot be predicted. One person may move quickly from lower levels of functioning to higher levels, while another person progresses quickly at first only to plateau later.

Below is a summary of the Levels of Cognitive Functioning Scale from the Rancho Los Amigos Hospital:

    Level I: No Response - Patient is totally unresponsive to the environment.

    Level II: Generalized Response - Patient reacts to stimuli in a non-specific, inconsistent manner. For example, he may lift his hand the same way regardless of the stimuli presented or the timing of the interaction.

    Level III: Localized Response - Patient reacts to stimuli in a specific, but inconsistent way. For example, she may incline her head toward a particular family member who visits daily but not to other family members who visit.

    Level IV: Confused-Agitated - Patient is very active but in a non-purposeful way. His behavior may seem very bizarre and out-of-control.

    Level V: Confused, Inappropriate Non-Agitated - Patient's memory and ability to focus and to learn new information may be significantly impaired; however, patient is able to respond to simple commands pretty consistently.

    Level VI: Confused-Appropriate - Patient exhibits purposeful behavior but is reliant on direction from others to a great extent. She may be able to generalize simple instructions. Focus, attention, orientation, and awareness are improved. Memory may still be impaired enough to present problems.

    Level VII: Automatic-Appropriate - Patient can perform activities of daily living but may still experience delayed learning abilities and impairments in executive (higher intellectual) functioning. For example, he may get himself ready for the day but have trouble recalling yesterday's instructions on how to arrange transportation. Minimal supervision may be needed.

    Level VIII: Purposeful and Appropriate - Patient's behavior is goal-oriented, and she is able to learn new information and generalize instruction without supervision. She is oriented regarding past and present events.

REFERENCES:(1) Greenery reprint of the Scales of Cognitive Functioning, with permission of Ranchos Los Amigos Hospital. (2) Hagen, C., Malkmus, D., Durham, P. "Measures of Cognitive Functioning in the Rehabilitation Facility." Brain Injury Association, Inc. 1984.


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