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Due to medical advancements, people who have sustained severe traumatic
brain injuries (TBI) have a better chance of survival. People can
be kept alive indefinitely with artificial respiration and alternative
feedings/nutrition. However, with all of these advancements in the
care of survivors of severe TBI, some survivors come out of coma (open
eyes), but never regain mental function. There has been much debate
over what to call this state of wakefulness without cognizant mental functioning.
This article discusses several of the options. Jennett and Plum believe
that of all the terms discussed, Persistent Vegetative State most
accurately describes this condition.
In the syndrome, as described by the authors, the patient has opened his/her eyes (come out of coma), but is only responding to the environment in a generalized way. The patient may respond to unpleasant stimuli with a slow, dystonic flexor response after a noticeable delay. Grasp reflexes, scratching, reaching for an unpleasant stimulus, postural changes, chewing and teeth grinding were also noted. Patients are silent except for vocalized grunts and groans. These symptoms are the result of diffuse brain damage that could have occurred in many different areas of the brain, and prognosis for recovery is guarded. Use of medical equipment, such as an EEG to measure electrical activity in the brain, is the best way to tell if the brain is still functioning and, if so, at what level. However, this equipment is not available to the bedside clinician. Several terms have been used to describe this state of being after severe TBI. The first is Brain Death,or Coma Depasse. Brain Death occurs when damage to the brain is so severe that there is no activity in the brain. Doctors may see some primitive reflexes but no spontaneous respiration. Patients will survive for only a few days. This term does not describe the syndrome Jennett and Plum described because it may last for months or years, given proper nutrition and care, not just a few days. The second term, Akinetic Mutism, describes an "intermittent disturbance of consciousness." The authors disagree with this term for semantic reasons. Jennett and Plum state that akinesia and mutism do not always go together. The next terms are Permanent, Irreversible,or Prolonged Coma,and Stuporor Dementia. "Permanent" and "Irreversible" are too strong of words to use for the syndrome Jennett and Plum described, and "Prolonged" is too weak. "Persistent," the authors argue, is accurate in that it means that the person does not necessarily live in this state of being forever but that it is likely. "Stupor" and "Dementia" are inappropriate because they are used to describe other conditions with different characteristics. Next, are the terms Decerbrateand Decorticate State. These terms describe different types of motor dysfunction due specifically to damage in the brain stem. The authors deem these terms misleading because they may imply that the damage is in one specific area and only affect the motor system. Apallic Syndromeis another inappropriate term. The complete Apallic Syndrome is characterized by "a complete loss of higher function with an isoelectric EEG and much reduced cerebral blood-flow and metabolism in supratentorial structures" (p. 736). This syndrome can also occur partially or incompletely. Jennett and Plum do not like this term because it is confusing to not only laymen, but also medical professionals. This term is very rarely used in the medical world. Apallic Syndrome also "assumes an unproven pathology" (p. 736). Clinicians cannot diagnose this condition without access to complicated medical equipment. The bedside clinician cannot diagnose whether the cortex is functioning or not. Last, is the term Locked-in Syndrome.This term describes a patient who is "tetraplegic, mute but fully alert" (p. 736). The motor pathways have been significantly damaged. Patients with Locked-in Syndrome are unable to move anything but their eyes and jaw, but are fully aware and cognitively intact. This is clearly not the case in the syndrome the authors described. After debating the use of all the above terms, the authors concluded that Persistent Vegetative State best describes the syndrome for several reasons. "It describes behaviour, and it is only data about behaviour which will always be available, and in every patient, because such observations are independent of special procedures such as EEG and measurements of cerebral blood-flow or metabolism" (p. 736). This term is readily understood by laymen and medical personnel alike, and has already been used to describe such a state of being. "What is common to all patients in this vegetative, mindless state is that, as best can be judged behaviourly, the cerebral cortex is not functioning, whether the lesion be in the cerebral cortex itself, in subcortical structures, the brain-stem, or in all these sites" (p.737).
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