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PubMedDate not supplied

Prediction of outcome of prolonged coma caused by brain damage.

Thirty-one prolonged coma patients, who continued in a comatose state for at least 2 months, were classified electrophysiologically employing EEG, a compressed spectral array of continuous EEG frequency analysis, BSR, SEP and SSEP. The prognoses of long-term follow-up (at least 8 months) in these patients were compared with the results of such electrophysiological analysis and with the neurological gradings of the prolonged coma patients. In the continuous EEG frequency analysis, 22 cases were classified as having a changeable spectrogram, nine cases as having a slow monotonous spectrogram, and no cases as having a borderline spectrogram. We also classified the changeable spectrograms into the following three patterns: no desynchronization, slight desynchronization, and desynchronization. The nine cases with a slow monotonous spectrogram revealed severe damage of the brain stem and cerebral function with multimodality evoked potentials, and most of these cases could not survive without assisted respiration. The 22 cases with a changeable spectrogram had mild damage of the brain stem and cerebral function with multimodality evoked potentials, and these cases were identical with a persistent vegetative state. Three of the cases showed a changeable spectrogram that revealed a desynchronization pattern, normal BSR and normal N20 of SEP and SSEP, recovered spontaneously from the persistent vegetative state within 6 months after electrophysiological evaluation. We conclude that not only a neurological but also an electrophysiological classification is necessary to evaluate the brain function and prognosis of prolonged coma.

Adolescent↗

PubMed2005

Information processing in severe disorders of consciousness: vegetative state and minimally conscious state.

OBJECTIVE: To study the presence of electrophysiological indicators of remaining cortical functions in patients with persistent vegetative state (PVS) and minimally conscious state (MCS). Previous electrophysiological and PET data indicated that some PVS patients have partially intact cortical processing functions. However, it remains unclear whether the reported patients were representative for PVS population or just some exceptional cases. METHODS: Event-related brain responses to stimuli of different complexity levels, recorded in 98 patients with extremely severe diffuse brain injuries, 50 of which in PVS. Four main indicators of cortical functions were: (i) N1-P2 complex as an index of simple, undifferentiated cortical processing; (ii) mismatch negativity as an index of pre-attentive, probably unconscious, cortical orientation; (iii) P3 wave as an index of deep cortical analysis of physical stimuli, and (iv) brain responses to semantic stimuli. RESULTS: Cortical responses were found in all PVS patients with a background EEG activity > 4 Hz. All responses investigated, including those to semantic stimuli that indicated comprehension of meaning, occurred significantly above chance, though less frequently than in patients with severe brain injuries who were conscious. CONCLUSIONS: Cortical responses were lacking in most patients with severe EEG slowing (< 4 Hz). Follow-up data revealed that the presence of a mismatch negativity, a short disease duration, and the traumatic etiology were related to a better outcome. SIGNIFICANCE: The data show that in a subpopulation of PVS patients with preserved thalamocortical feedback connections, remaining cortical information processing is a consistent finding and may even involve semantic levels of processing.

Auditory Cortex↗

PubMed2003

Decompressive craniectomy for severe traumatic brain injury: Evaluation of the effects at one year.

OBJECTIVE: To assess the effect on outcome (1 yr) of decompressive craniectomy performed within or after the first 24 hrs post-trauma in severely head-injured trauma patients with intractable cerebral hypertension. DESIGN: Retrospective cohort study. SETTINGS: Intensive care unit of a university hospital. PATIENTS: Among 816 patients with severe head trauma (Glasgow Coma Scale < or =8), 40 underwent decompressive craniectomy. After data collection, patients were divided into two groups: early and late decompressive craniectomy. An early decompressive craniectomy was performed within the first 24 hrs in patients according to the following criteria: a Glasgow Coma Scale score <6 and the existence of clinical signs of cerebral herniation (absence of pupillary reflexes), correlated with abnormalities in computed tomography scan including hematoma, appearance of diffuse or unilateral brain swelling, and/or cerebral herniation. The intracranial pressure in these patients was not measured before the decompressive craniectomy was performed. A late decompressive craniectomy (>24 hrs) was performed according to following criteria: an intractable intracranial hypertension with intracranial pressure >35 mm Hg, a unilateral or bilateral absence of pupillary reflexes, and the same abnormalities in computed tomography scan as previously described. INTERVENTION: Twenty-seven patients with signs of cerebral herniation required the procedure at the time of initial evacuation of a mass lesion. In 13 patients, decompressive craniectomy was performed because of elevated intracranial pressure refractory to medical treatment consisting of cerebrospinal fluid derivation, deep sedation, osmotherapy, hyperventilation, and nesdonal or propofol. MEASUREMENTS AND MAIN RESULTS: Five patients (19%) in whom an early decompressive craniectomy was performed had good recoveries (social rehabilitation), eight patients (30%) remained in a persistent vegetative state or with a severe disability, and 14 died (52%). On the other hand, the performance of late decompressive craniectomy in case of medical treatment failure was followed by social rehabilitation in five patients (38%) and death in three patients (23%). A persistent vegetative state or a severe disability was observed in five patients (38%). Meningitis or cerebral abscess occurred in six patients after decompressive craniectomy and were easily cured by antibiotic treatment. CONCLUSIONS: In 40 patients with intractable intracranial hypertension and at very high risk of brain death, decompressive craniectomy allowed 25% of patients to attain social rehabilitation at 1 yr.

Adult↗

PubMed1991

Refusal of tube feeding as seen from a patient advocacy organization: a comparison with landmark court cases.

OBJECTIVE: To determine how closely high court decisions regarding tube feeding are a reflection of the situations that occur in the general population. DESIGN: A retrospective review was conducted of memos recording inquiries made to the Society for the Right to Die (SRD), a patient advocacy organization. Characteristics of clients were compared to characteristics of individuals considered in landmark "right-to-die tube feeding cases during the same period of time. RESULTS: Information from 116 memos of inquiries made from 1985 through mid-1990 was compared to 20 court cases, and significant differences were identified. The average age of the SRD clients was 77.6 (+/- 18.4) years compared to 55.1 (+/- 22.8) years for the court cases (P less than 0.001). Of the clients, 79% were 70 years of age or older and 28% were 90 or older; in contrast, 7 (35%) of subjects in the court cases were 70 years of age or older, and none was over 90 (P less than 0.001). In addition, whereas 14 (70%) of the court cases dealt with individuals in a persistent vegetative state, only 17 (15%) of SRD clients carried that diagnosis (P less than 0.001), with the remainder suffering from dementia, various stages of coma, or a variety of other debilitating disorders. The sex distribution, year of inquiry or year of court decision, and geographic distribution were similar. Some states were overrepresented in both groups. CONCLUSION: High court cases may inadequately reflect the majority of situations that arise on a day-to-day basis. Elderly individuals, in particular those who are not in a persistent vegetative state, are significantly underrepresented.

Aged↗

PubMed2006

The functional outcome of patients requiring over 28 days of intensive care: a long-term follow-up study.

OBJECTIVE: To measure functional outcome of long-stay intensive care unit patients in the Australian population. METHODS: All 68 patients admitted between July 2000 and July 2002 who spent 28 consecutive days or longer in a 30-bed university-affiliated medical-surgical ICU. MAIN OUTCOMES MEASURES: Glasgow Outcome Scores were recorded by chart review or telephone in the third quarter of 2003, giving a follow-up of 1-3 years (mean, 2 years). RESULTS: Patients comprised 22 trauma (32%), 16 cardiothoracic (24%) and 15 each (22%) general medical and surgical patients. Average age was 59.2 years (SD, 18.3 years), and mean APACHE II score was 22.2 (range, 7-52). Fourteen of 68 patients (21%) died during the hospital admission. Of the 54 patients discharged, 53 were followed up, and one was untraceable. Nineteen of these 53 (36%) had died. Of the 34 survivors (64% of hospital survivors, 50% of long-stay ICU patients), 17 (50%) were leading normal active lives, 15 (44%) were disabled but independent, with two (6%) needing daily support. None were in a persistent vegetative state. CONCLUSIONS: Of 68 long-stay ICU patients, an average of 2 years after discharge, 50% were alive, including 25% living normal active lives. The remaining 25% described some disability. In most cases (88%), this was mild: only two patients (3% of the total group) depended on daily support. No patients were left in a persistent vegetative state.

Adult↗

PubMed1989

Ethical issues in brain death and multiorgan transplantation.

There is a consensus in Western society that "brain death" is the medical and legal standard for human death. Patients in persistent vegetative states may have lost their "personhood," but they are not dead. It may be desirable to maintain the physiologic processes of a brain-dead pregnant woman to permit the birth of her child. The determination of brain death and plans for multiorgan transplantation should be conducted independently. It is axiomatic that the multiorgan transplantation donor must be dead. Therefore, living anencephalic infants and patients in persistent vegetative states cannot be organ donors. It is permissable to temporarily maintain the physiologic processes of brain-dead patients in order procure their organs for transplantation. Society will have to decide if money spent on multiorgan procurement and transplantation is better spent in other areas of health care.

Brain Death↗

PubMed2000

The role of evoked potentials in anoxic-ischemic coma and severe brain trauma.

The early recognition of comatose patients with a hopeless prognosis-regardless of how aggressively they are managed-is of utmost importance. Median somatosensory evoked potentials supplement and enhance neurologic examination findings in anoxic-ischemic coma and severe brain trauma, and are useful as an early guide to outcome. The key finding is that bilateral absence of cortical evoked potentials, generated by thalamocortical tracts, reliably predicts unfavorable outcome in comatose patients after cardiac arrest, and correlates strongly with death or persistent vegetative state in severe brain trauma. The author studied 50 comatose patients with preserved brainstem function after cardiac arrest. All 23 patients with bilateral absence of cortical evoked potentials died without awakening. Neuropathologic study in seven patients disclosed widespread ischemic changes or frank cortical laminar necrosis. The remaining 27 patients with normal or delayed central conduction times had an uncertain prognosis because some died without awakening or entered a persistent vegetative state. The majority of patients with normal central conduction times had a good outcome, whereas a delay in central conduction times increased the likelihood of neurologic deficit or death. This report includes a systematic review of the literature concerning adults in anoxic-ischemic coma and severe brain trauma, in which somatosensory evoked potentials were used as an early guide to predict clinical outcome. Greater use of somatosensory evoked potentials in anoxic-ischemic coma and severe brain trauma would identify those patients unlikely to recover and would avoid costly medical care that is to no avail.

Adult↗

PubMedDate not supplied

Neocortical death in infants: behavioral, neurologic, and electroencephalographic characteristics.

Neocortical death is a form of the persistent vegetative state characterized by the maintenance of sleep/wakeful cycles and spontaneous respirations and the lack of cognitive function. It is difficult to diagnose in neonates and young infants because their cognitive skills are limited by inexperience and by immaturity of the central nervous system. Because neocortical death has not been described previously for this age group, we report the neurologic, behavioral, electroencephalographic, and computed tomographic characteristics of three infants who survived in the persistent vegetative state following severe brain injury. Each infant appeared to exhibit some complex behaviors, including interaction with the environment and the examiners, although the electroencephalograms documented no electrical activity of cerebral origin. Computed tomography revealed extensive destruction of the cerebral hemispheres. Infants and newborns with a history suggesting brain injury and with the neurologic and behavioral characteristics described here should be evaluated with serial electroencephalograms and computed tomography to diagnose the syndrome of neocortical death.

Brain Damage, Chronic↗

PubMed2004

Permanent vegetative state: usefulness and limits of a prognostic definition.

Jennett and Plum's 1972 naming of post-coma unresponsiveness as "persistent vegetative state (PVS)" characterised the condition as essentially irrecoverable and insentient. The evidence for these propositions was always weak, and they have been largely disproved by more recent research. Nonetheless, the definition and the attitudes it embodies remain generally accepted, resting as they do on a firm foundation of medical attitudes to disability and a public eagerness to evade uncomfortable facts. The first step in altering our approach to people with this form of communication impairment must be to rectify our understanding of the terminology.

Humans↗

PubMed2005

Cerebral acid-base homeostasis after severe traumatic brain injury.

OBJECT: Brain tissue acidosis is known to mediate neuronal death. Therefore the authors measured the main parameters of cerebral acid-base homeostasis, as well as their interrelations, shortly after severe traumatic brain injury (TBI) in humans. METHODS: Brain tissue pH, PCO2, PO2, and/or lactate were measured in 151 patients with severe head injuries, by using a Neurotrend sensor and/or a microdialysis probe. Monitoring was started as soon as possible after the injury and continued for up to 4 days. During the 1st day following the trauma, the brain tissue pH was significantly lower, compared with later time points, in patients who died or remained in a persistent vegetative state. Six hours after the injury, brain tissue PCO2 was significantly higher in patients with a poor outcome compared with patients with a good outcome. Furthermore, significant elevations in cerebral concentrations of lactate were found during the 1st day after the injury, compared with later time points. These increases in lactate were typically more pronounced in patients with a poor outcome. Similar biochemical changes were observed during later hypoxic events. CONCLUSIONS: Severe human TBI profoundly disturbs cerebral acid-base homeostasis. The observed pH changes persist for the first 24 hours after the trauma. Brain tissue acidosis is associated with increased tissue PCO2 and lactate concentration; these pathobiochemical changes are more severe in patients who remain in a persistent vegetative state or die. Furthermore, increased brain tissue PCO2 (> 60 mm Hg) appears to be a useful clinical indicator of critical cerebral ischemia, especially when accompanied by increased lactate concentrations.

Acid-Base Equilibrium↗

PubMed1999

The influence of physician race, age, and gender on physician attitudes toward advance care directives and preferences for end-of-life decision-making.

OBJECTIVE: To determine whether physicians' preferences for end-of-life decision-making differ between blacks and whites in the same pattern as patient preferences, with blacks being more likely than whites to prefer life-prolonging treatments. DESIGN: A mailed survey. SETTING AND PARTICIPANTS: American Medical Association (AMA) and National Medical Association (NMA) databases. To enrich the sample of black physicians, we targeted physicians in the AMA database practicing in high minority area zip codes and graduates of the traditionally black medical schools. MAIN OUTCOME MEASURES: Self-reported physician attitudes toward end-of-life decision-making and preference of treatment for themselves in persistent vegetative state or organic brain disease compared by race, controlling for age and gender. RESULTS: The 502 physicians (28%) who returned the questionnaire included 280 white and 157 black physicians. With regard to attitudes toward patient care, 58% of white physicians agreed that tube-feeding in terminally ill patients is "heroic," but only 28 % of black physicians agreed with the statement (P < .001). White physicians were more likely than black physicians to find physician-assisted suicide an acceptable treatment alternative (36.6% vs 26.5% of black physicians) (P < .05). With regard to the physicians preferences for future treatment of themselves for the persistent vegetative state scenario, black physicians were more than six times more likely than white physicians to request aggressive treatments (cardiopulmonary resuscitation, mechanical ventilation, or artificial feeding) for themselves (15.4% vs 2.5%) (P < .001). White physicians were almost three times as likely to want physician-assisted suicide (29.3% vs 11.8%) (P < .001) in this scenario. For a state of brain damage with no terminal illness, the majority of all physicians did not want aggressive treatment, but black physicians were nearly five times more likely than white physicians (23.0% vs 5.0%) (P < .001) to request these treatments. White physicians, on the other hand, were more than twice as likely to request physician-assisted suicide (22.5% vs 9.9%), P < .001 in this scenario. CONCLUSIONS: Physicians preferences for end-of-life treatment follow the same pattern by race as patient preferences, making it unlikely that low socioeconomic status or lack of familiarity with treatments account for the difference. Self-denoted race may be a surrogate marker for other, as yet undefined, factors. The full spectrum of treatment preferences should be considered in development of guidelines for end-of-life treatment in our diverse society.

Adult↗

PubMed1994

Tube feeding. Internists' attitudes regarding ethical obligations.

BACKGROUND: Little is known about the attitudes of internists regarding their ethical obligation to provide or withhold tube feeding in three clinical contexts when patient preferences are not known: acute pneumonia, severe dementia, and persistent vegetative state. METHODS: A written questionnaire with patient scenarios was mailed to a randomized national sample of 1000 internist members of the American College of Physicians. RESULTS: Response was received from 58% of our sample (n = 581). Only physicians with personal experience with tube feeding decisions were included in the subsequent analysis (n = 326). Respondents were mostly male board-certified internists active in patient care in urban/suburban settings. Physicians demonstrated a predominant attitude for each scenario: 98% favored initiation of tube feeding for the patient with acute pneumonia; 84% opposed initiation of tube feeding for the patient with advanced dementia when depicted with a mixed happy/sad affect; and 80% favored withdrawal of tube feeding for the patient with established persistent vegetative state. Sixteen percent (n = 51) described tube feeding as basic humane care, whereas 84% (n = 265) believed tube feeding is medical therapy. Physicians were more opposed to tube feeding in certain patient scenarios than the literature suggests occurs in actual practice. CONCLUSIONS: Our data suggest that when patient wishes are not known, physician decisions regarding tube feeding are strongly influenced by prognosis. State legislation that categorizes tube feedings differently from other medical treatments conflicts with the judgment of the majority of internist respondents.

Adult↗

PubMed2004

Vegetative state and brain death: philosophical and ethical issues from a personalistic view.

This article intends to precise the anthropologic fundaments of the Persistent Vegetative State starting from the concept of the human person, as it has been described in relation to the philosophical-theological thought of Thomas Aquinas and other more recent personalists (J. Maritain, E. Mounier, E. Gilson, S. Vanni Rovighi). This view is largely shared by the catholic thought and is present in the Teachings of the Catholic Church. The central point of reflection is in affirming the double unity of the human person: the substantial unity of the spiritual body-soul; the uniqueness of the animative principle (soul) as "form" of corporeity. The spiritual soul is the active principle not only of the superior activities (thought, liberty) but also of the vegetative-sensitive activity of the organism which is part of the person. Thus, as long as a vital unit exists in the individual person, there will exist the presence of a spiritual soul in the organism, defined as a whole unit, and the subject must be considered alive, even when gravely and persistently hindered in the application of his/her cognitive functions.

Brain Death↗

PubMed2005

MR Imaging of nonalcoholic Wernicke encephalopathy: a follow-up study.

We investigated the correlation of MR imaging features with the pathological evolution and prognosis of nonalcoholic Wernicke encephalopathy. A retrospective review and analysis was conducted of 6 cases of nonalcoholic Wernicke encephalopathy, consisting of MR imaging features, clinical characteristics, and outcomes after thiamine administration. One patient died, 1 patient entered a persistent vegetative state, and the others recovered fully from Wernicke encephalopathy within 2 weeks to 1 year after thiamine administration. Typical MR imaging showed areas of increased T2-weighted and fluid-attenuated inversion recovery (FLAIR) signals symmetrically surrounding the aqueduct and the third ventricle, at the floor of fourth ventricle, in the medial thalami, and in the capita of caudate nuclei. Two patients presenting without coma showed increased T2-weighted and FLAIR signals of the periaqueductal area only. All 4 patients presenting with coma showed increased T2-weighted and FLAIR signals symmetrically in the medial thalami and in the capita of caudate nuclei. Of the 4 patients with coma, 2 patients with deep coma showed increased T2-weighted and FLAIR signals in the medial thalami and caudate nuclei as well as in the frontal and parietal cortices. According to the follow-up results, increased T2-weighted and FLAIR signals in the 4 patients without cortical damage decreased in intensity, consistent with clinical recovery within 2 weeks to 1 year. The patient in a persistent vegetative state exhibited progressive atrophy of the whole brain during the 2 years of the follow-up study. MR imaging is helpful not only to diagnose acute nonalcoholic Wernicke encephalopathy but also to evaluate the pathologic evolution and prognosis of the disorder.

Adolescent↗

PubMedDate not supplied

A panencephalopathic type of Creutzfeldt-Jakob disease with selective lesions of the thalamic nuclei in 2 Swiss patients.

Creutzfeldt-Jakob disease (CJD), a subacute spongiform encephalopathy, is generally included among the group of human and animal diseases which is transmissible by a non-conventional agent, the prion, whose expression is conditioned by the host's genome. The process leading to neuropathological changes is still unknown. We report the neuropathological findings in 2 cases of the "panencephalopathic" variant of CJD, which is relatively common in Japan, but extremely rare in Europe and North America. When compared with the classical form this variant is characterized by a relatively long clinical course with persistent vegetative state and primary involvement of the white matter presenting in the form of demyelination and gemistocytic gliosis. The selective involvement of certain thalamic nuclei is a particular pathological feature in both our cases. There was practically complete neuronal loss with diffuse gliosis of the anteroventral (AV) and dorsomedial (DM) nuclei, while the neuronal loss in the pulvinar remained moderate: the other nuclei were apparently spared. A similar involvement of the thalamus has been reported in fatal familial insomnia, a recently described prion disease in which these lesions are predominant. A comparable distribution has also been observed in other degenerative neurological diseases such as Steele-Richardson-Olszewski disease, Alzheimer disease, and thalamic dementia (selective thalamic atrophy or with multisystemic degeneration). The AV and DM nuclei, commonly referred to as "limbic thalamus" represent phylogenetically the most recent thalamic structures and would appear to play an important role in the superior functions in man as memory, attention and awareness. In our cases thalamic lesions are selective, bilateral, and symmetric, not explained by Wallerian degeneration. These lesions may be due to the primary pathogenetic properties of the infectious agent. The rapid clinical evolution in a persistent vegetative state could be consequential to precocious and severe disfunction of the limbic thalamus.

Creutzfeldt-Jakob Syndrome↗

PubMed1996

Legal position of euthanasia in NSW.

There is a great deal of confusion surrounding the terminology used when discussing euthanasia. In addition, there are common misconceptions flowing from that confusion about what can or cannot be legally done when caring for a person who is dying, or for those in a persistent vegetative state.

Ethics, Nursing↗

PubMed2006

Serum neuron-specific enolase as early predictor of outcome after in-hospital cardiac arrest: a cohort study.

INTRODUCTION: Outcome after cardiac arrest is mostly determined by the degree of hypoxic brain damage. Patients recovering from cardiopulmonary resuscitation are at great risk of subsequent death or severe neurological damage, including persistent vegetative state. The early definition of prognosis for these patients has ethical and economic implications. The main purpose of this study was to investigate the prognostic value of serum neuron-specific enolase (NSE) in predicting outcomes in patients early after in-hospital cardiac arrest. METHODS: Forty-five patients resuscitated from in-hospital cardiac arrest were prospectively studied from June 2003 to January 2005. Blood samples were collected, at any time between 12 and 36 hours after the arrest, for NSE measurement. Outcome was evaluated 6 months later with the Glasgow outcome scale (GOS). Patients were divided into two groups: group 1 (unfavorable outcome) included GOS 1 and 2 patients; group 2 (favorable outcome) included GOS 3, 4 and 5 patients. The Mann-Whitney U test, Student's t test and Fisher's exact test were used to compare the groups. RESULTS: The Glasgow coma scale scores were 6.1 +/- 3 in group 1 and 12.1 +/- 3 in group 2 (means +/- SD; p < 0.001). The mean time to NSE sampling was 20.2 +/- 8.3 hours in group 1 and 28.4 +/- 8.7 hours in group 2 (p = 0.013). Two patients were excluded from the analysis because of sample hemolysis. At 6 months, favorable outcome was observed in nine patients (19.6%). Thirty patients (69.8%) died and four (9.3%) remained in a persistent vegetative state. The 34 patients (81.4%) in group 1 had significantly higher NSE levels (median 44.24 ng/ml, range 8.1 to 370) than those in group 2 (25.26 ng/ml, range 9.28 to 55.41; p = 0.034). CONCLUSION: Early determination of serum NSE levels is a valuable ancillary method for assessing outcome after in-hospital cardiac arrest.

Aged↗

PubMed2002

Sleep cycle in patients in a state of permanent unconsciousness.

Since the recent diagnostic criteria for persistent vegetative state (PVS) require the presence of a sleep-wake cycle, certain patients in similar conditions should be excluded from PVS. Since the diagnosis of PVS might correlate with legal issues, an accurate definition is necessary. To clarify the clinical significance of a sleep-wake cycle, 12 patients in a state of permanent unconsciousness after brain damage were clinically and electrophysiologically reviewed. In addition to routine EEG, evoked potentials and MRI, the simultaneous recordings of EEG and patients by videotape were performed for 24 hours. Four patients who showed severe brain stem damage did not show a sleep-wake cycle. In the other eight patients, a sleep-wake cycle was observed. However, among these patients there was no obvious difference in their clinical status. Although these data suggest that the presence of a sleep-wake cycle might reflect the brain stem damage, it is considered that the presence of a sleep-wake cycle might be unnecessary for the diagnostic criteria for PVS. Further study of various forms of brain damage will provide better understanding of the significance of the presence of a sleep-wake cycle.

Adolescent↗