Epidemiological studies on patients with a persistent vegetative state

HM-PAO-SPECT in persistent vegetative state after head injury: prognostic indicator of the likelihood of recovery?

Management of patients presenting with traumatic persistent vegetative state (PVS) calls for extensive resources. The ability to predict whether or not a patient is likely to recover is a critical issue. In 12 patients with PVS admitted consecutively for early rehabilitation after head injury, pattern of brain activity was measured by 99mTc-hexamethyl-propylenamineoxime (99mTc-HM-PAO) brain SPECT (single photon emission computer tomography). All patients were re-investigated after a mean observation period of 3 years. A global reduction of cortical blood flow was a reliable predictor of poor long-term outcome, but the demonstration of only focal deficits did not reliably indicate a favourable outcome. Brain SPECT may help to improve outcome prediction in patients with traumatic PVS.

Prognosis for recovery from prolonged posttraumatic unawareness: logistic analysis

This study reviews the course and outcome of 130 patients who remained in a state of prolonged unawareness 30 days after severe cranio-cerebral trauma. Prognostic indicators and outcome were fitted by a logistic model. The significant prognostic factors observable in the first week after trauma were found to be ventilatory status, motor reactivity and significant extraneural trauma. The significant prognostic factors after the first month of unawareness were early ventilatory status, early motor reactivity, late epilepsy and hydrocephalus. The estimated probability of recovery of awareness (that is, consciousness) ranged from 0.94 in patients with early decorticate posturing in the absence of both extraneural trauma and ventilatory disturbance to 0.06 in patients with flaccidity, extraneural trauma and ventilatory disturbance in the first week after injury.

Time-related sequelae of TBI in patients with prolonged post-comatose unawareness (PC-U) state

Seventy-two patients who were in a post-comatose unawareness state for periods longer than 1 month following traumatic brain injury recovered consciousness thereafter. The incidence of residual sequelae of brain trauma in relation to duration of unawareness was studied. The incidence of motor disability, communication disorders, cognitive disturbances and malbehaviour was studied in the patients recovering consciousness after 1, 2, 3 and 6 months. It was found that no significant differences were found in the incidence of the above-mentioned residual sequelae of brain-damaged patients in relation to duration of post-comatose unawareness. However, 76.1% (51/67) of the patients who recovered consciousness and survived the first year following injury were living at home. Most of these were patients who recovered consciousness within the first 3 months following trauma. None of the patients who were in post-comatose unawareness longer than 6 months did so, Five patients (6.9%) died during the first year. Motor disability, independence in activities of daily living, vocational outcome and place of living were significantly related to duration of prolonged unawareness state whereas the disturbances in high mental functions did not. Although the vocational outcome of patients with post-comatose unawareness is not good, the fact that most of them are still able to live at home, having an acceptable quality of survival, justifies, according to our experience, the comprehensive rehabilitation programme.

Deep-brain stimulation in a persistent vegetative state: follow-up results and criteria for selection of candidates

Eight cases of a persistent vegetative state caused by brain damage were treated by chronic deep-brain stimulation (stimulation target: the mesencephalic reticular formation and/or non-specific thalamic nucleus) over a period of more than 6 months. Three of the patients are currently able to communicate and to express their demands by voice and one other patient has recovered very close to this state. These four cases showed changeable spectrograms with desynchronization on continuous EEG recording and all components of the BSR and SER could be recorded except for prolonged latency of both N20 (SER) and the V wave (BSR) 2 months after the initial coma. Following chronic deep-brain stimulation, EEG and behavioural arousal responses were observed with increased r-CBF, r-CMRO2 and r-CMRGL in the whole brain tissue. After 3-6 months of chronic deep brain stimulation, the prolonged coma scale rose in four of the eight cases and three cases emerged from the persistent vegetative state. Transmitter substances and their metabolites were also found to be increased in the CSF after chronic deep-brain stimulation. Based on these findings, chronic deep-brain stimulation represents a useful kind of treatment that can lead to emergence from a persistent vegetative state, if the candidate is selected by electrophysiological studies 2 months after the initial insult and if the stimulation is applied for more than 6-8 months using a high-safety chronic deep-brain stimulating instrument.

Outcome in 134 patients with prolonged posttraumatic unawareness. Part 1: Parameters determining late recovery of consciousness

A retrospective study of 134 patients in a condition of prolonged unawareness state (that is, in coma for over 1 month) following brain trauma was conducted in order to identify prognostic factors. Eight easily evaluated parameters were found to be significant for predicting nonrecovery of consciousness. The following six features were present during the early posttraumatic phase (that is, during the 1st week after trauma): fever of central origin; diffuse body sweating; disturbances in antidiuretic hormone secretion; abnormal motor reactivity; respiratory disturbances; and diffuse nonneurological injuries. The first three features were manifestations of hypothalamic damage. Two factors, evident at a late phase following injury (after the 1st week posttrauma), namely late epilepsy and communicating hydrocephalus, were also significant in predicting nonrecovery.

Outcome in 134 patients with prolonged posttraumatic unawareness. Part 2: Functional outcome of 72 patients recovering consciousness

Most publications regarding the outcome of traumatic brain injury include patients with periods of unconsciousness of varying durations. The aim of the present paper is to describe the outcome of 72 patients who suffered from prolonged unawareness for more than 30 days and subsequently recovered consciousness. Almost half of the patients were independent in activities of daily living and another 20% were only partially dependent. Cognitive and behavioral deficits were the most common central nervous system sequelae of injury. Eight patients (11.1%) were able to resume working in the open job market and 35 (48.6%) were engaged in sheltered workshops. Most of the patients (72%), including all those who were working, were living with their families. Although the mean rehabilitation period was about 15 months, over 70% of these severely injured patients are considered to be socially integrated, enabling them to enjoy a reasonable quality of life.

Chronic vegetative state after severe head injury: clinical study; electrophysiological investigations and CT scan in 15 cases

Fifteen cases of chronic vegetative state (CVS), following severe head injury and lasting for two years or more, are reported. Vegetative state, in most instances after a period of coma, consists of a return of wakefulness accompanied by an apparent total lack of higher mental activity. A protracted period of vegetative state has been chosen to ensure that the possibility of further recovery could virtually be excluded. The term of CVS could therefore be reasonably used to designate these cases. Moreover, cerebral lesions were then thought to be the same as in neuropathological studies. Severe head injury, responsible for CVS, initially affected adults in 11 cases and children in four cases. The range of duration of the vegetative state was 2 to 14 years, with a mean of five years. The data of clinical study and electrophysiological investigations (EEG, brain stem auditory evoked potentials, somatosensory evoked potentials) are reported. A CT scan was carried out in each case to study the impairment of cerebral hemispheres and brain stem, with particular attention to the ventricular size. The results confirm that in the CVS, lesions affect mainly the hemispheres, while brain stem functions are mainly preserved. Vegetative State (VS) is the term proposed by Jennett and Plum (1972) to describe the condition that sometimes emerges after a period of coma, after a severe head injury (SHI). This condition consists of a return of wakefulness accompanied by an apparent total lack of higher mental activity. A practical definition of this state characterised by wakefulness without responsiveness is that the eyes open spontaneously and/or in response to verbal stimuli. Sleep-wake cycles exist. The patients can neither obey simple orders nor locate painful stimuli. They utter no comprehensible words. Blood pressure and breathing remain steady. It is much more difficult to specify exactly how long such a state must persist before it can be confidently declared permanent. Persistent vegetative state, or chronic vegetative state (CVS) is one of the five categories of the Glasgow Outcome Scale (Jennett and Bond, 1975). Bricolo et al (1980) think that the term CVS should never be applied before completion of the first year after the onset of traumatic coma. It actually seems possible to exclude the possibility of any further recovery after unresponsiveness for one year. The term CVS may then be rightfully used to denote this condition. For such protracted periods of VS, we have tried to state in a retrospective study the clinical and electroencephalographic (EEG) course.(ABSTRACT TRUNCATED AT 400 WORDS)

Prognosis of the posttraumatic vegetative state

Of 1373 patients who, following severe brain injury had been comatose for over 6 hours, 140 (10%) were in a vegetative state one month later. Fifty-nine regained consciousness but none of those aged over 40 became independent during the first year. Of those still in a vegetative state after 3 months, none became independent irrespective of age. Of all patients comatose for over 6 hours after severe brain injury, only 1% was in a vegetative state after one year. Certain scores for features such as age, pupillary reactions, eye-opening and eye movements indicate either a favourable prognosis, a fatal outcome or irreversible coma. It is only in some 10% of all patients in coma or in a vegetative state during the first two weeks after the accident that it is possible to predict with a high degree of probability (p greater than 0.95), an unfavourable outcome (death or irreversible coma) within one year. At no time after the onset of coma is it possible to predict or distinguish, with a fair degree of probability (e.g. p greater than 0.80), those patients who will remain in a vegetative state from those who will die.

Unexpected improvement after prolonged post-traumatic vegetative state

Presentation of an unusual case of severe head injury in which, after three and a half years of vegetative state, a gradual return to consciousness and personality occurred.

Late neuropathological consequences of strangulation

A case of a young man who was a victim of strangulation is presented. He arrived at the hospital in refractory status epilepticus, controlled only with intravenous pentobarbital. The initial CT scan showed mild cortical edema. Two days later, a CT scan showed diffuse cortical swelling and bilateral basal ganglia infarcts. Upon discontinuation of pentobarbital therapy, his neurological examination revealed spontaneous ventilation and a gag reflex. A CT scan 4 weeks after the insult demonstrated hypodensities in both cerebral hemispheres and hydrocephalus. EEG was isoelectric throughout his hospitalization. He survived nearly 5 months and succumbed to pneumonia. Neuropathological examination demonstrated severe encephalomalacia, multiple cystic infarcts and generalized compensatory ventriculomegaly. Microscopic examination was particularly remarkable for a pronounced gemistocytic astrocyte proliferation in the white matter. This case illustrates the long-term neuropathological consequences of severe, global hypoxia/ischemia and the paucity of intact brain required to maintain a persistent vegetative state.

Unexpected improvement after prolonged posttraumatic vegetative state

An 18-year-old girl suffered a severe head injury in a traffic accident. As a result, she was vegetative for about 21/2 years. She then showed signs of a gradually returning responsiveness. Six years after the accident, she is now able to comprehend and communicate, shows considerable interest in her surroundings and is able to establish interpersonal relationships. Moreover, the improvement is still continuing. Her severe contractures, however, prevent her from making full use of these regained mental capacities. Such a mental recovery after such a long-lasting vegetative state of traumatic origin has not previously been described.

Ethical issues in the treatment of patients with a remitting vegetative state

A case of remitting vegetative state is presented illustrating the need to draw a distinction between persistent and remitting vegetative states in brain-damaged patients. Standard ethical considerations regarding dying patients cannot be universally applied to remitting vegetative states, which are best handled in a context of an ethics of discretion, rather than an ethics of rules. Ethical obligations towards such persons are presented. When the patient cannot assent to withdrawal of treatment, it is suggested that decisions be made on the side of preserving life until the course becomes evidently downhill.

Five-year follow-up study of patients with persistent vegetative state

One hundred and ten patients with persistent vegetative state, were followed up for a period of five years from 1973 to 1978. Seventy-three per cent of the patients died during the period while about 10% of them recovered partially from the vegetative state. Among the recovered patients, only three became able to communicate, but two of these are not independent for their daily activites. Reactivity and clinical symptoms of 30 survivors were examined, but no great changes occurred during the last two years of the study.

Natural history of global and critical brain ischaemia. Part II: EEG and neurological signs in patients remaining unconscious after cardiopulmonary resuscitation

Of 125 patients who had no detectable cortical activity (DCA) on the electroencephalograph (EEG) immediately upon resuscitation from circulatory arrest of primary cardiovascular aetiology, 88 remained unconscious; these patients had their EEG and neurological status serially investigated until they died. Immediately upon re-establishment of circulation all cerebral functions could be absent; the brain death (irreversible loss of functions) was then signified by the appearance of poikilothermia, diabetes insipidus and reflex extension of the upper limb. Most often, some cranial nerve reflexes were present; the EEG configurations and related neurological signs then appeared in a sequence which resembled orderly postischaemic recovery: A phase without DCA was at first characterized by an exclusive presence of cranial nerve reflexes and then by the appearance of decerebrate posturing this phase was followed by another phase of intermittent cortical activity (ICA) with decorticate and stereotypic motor responses and a phase of continuous cortical activity (CCA) accompanied by stereotypic reactivity. These phases were most often incomplete due to failure of recovery of some cranial nerve reflexes or were abnormal due to the appearance of intermittent spikes and sharp waves. Progressive recovery could stagnate at any step and the cerebral functions be lost abruptly or gradually in reverse order of recovery. The decay was invariably due to cardiovascular or pulmonary complications. Brain autopsy revealed extensive neuronal loss and intravital autolytic changes in patients who had fulfilled clinical criteria of brain death for more than 72 h, but the histopathology showed no relationship to other clinical findings during the postischaemic course.

Vegetative state following coma in childhood: evolution and outcome

The data have been analysed for 17 children who showed features of the vegetative state following an acute illness that resulted in coma. 15 were under three years of age. Diffuse anoxia/ischaemia (N=12) and meningitis (N=4) were the most common causes of the comatose state. Seven children died, and nine of the 10 survivors have remained severely neurodevelopmentally handicapped, with no cognitive function (follow-up two months to five years). One child became ambulant a year after the initial insult and is moderately retarded. The findings suggest that children who develop the vegetative state following an illness resulting in coma have a poor prognosis and that decorticate or decerebrate responses, roving eye-movements and spontaneous blinking may be early indicators of its emergence.

Prolonged posttraumatic unconsciousness: therapeutic assets and liabilities

Prolonged coma following severe head injury is a serious condition because it implies a poor prognosis. In order to assess the magnitude of this phenomenon, the authors have reviewed 135 cases of posttraumatic unconsciousness lasting more than 2 weeks, from among the entire propulation of patients with severe head injury managed in 10 years in their neurosurgical intensive care unit. The incidence of prolonged coma was 4% of all patients with acute traumatic coma, and 0.6% of all hospitalized patients with head injury. By 1 year after trauma, 30% of the patients had died, 8% survived in a vegetative state, 31% survived with severe disabilities, and 31% had made a satisfactory recovery. The early clinical picture of prolonged unconsciousness has no predictive value as to further evolution. Patients emerge from unconsciousness in consecutive steps representing the restoration of increasingly complex neurological functions; the timing of these steps is very variable and sometimes covers several months. The time distribution of recovery steps in individual cases is of limited predictive value as to outcome. The most frequent state during the recovery process is the condition of wakefulness without awareness, which should not be pronounced "permanent" earlier than 1 year after injury.