Prognosis of the posttraumatic vegetative state

Distinct Spectral Profiles of Awake Resting EEG in Disorders of Consciousness: The Role of Frequency and Topography of Oscillations

The prolonged disorders of consciousness (PDOC) pose a challenge for an accurate clinical diagnosis, mainly due to patients' scarce or ambiguous behavioral responsiveness. Measurement of brain activity can support better diagnosis, independent of motor restrictions. Methods based on spectral analysis of resting-state EEG appear as a promising path, revealing specific changes within the internal brain dynamics in PDOC patients. In this study we used a robust method of resting-state EEG power spectrum parameter extraction to identify distinct spectral properties for different types of PDOC. Sixty patients and 37 healthy volunteers participated in this study. Patient group consisted of 22 unresponsive wakefulness patients, 25 minimally conscious patients and 13 patients emerging from the minimally conscious state. Ten minutes of resting EEG was acquired during wakefulness and transformed into individual power spectra. For each patient, using the spectral decomposition algorithm, we extracted maximum peak frequency within 1-14 Hz range in the centro-parietal region, and the antero-posterior (AP) gradient of the maximal frequency peak. All patients were behaviorally diagnosed using coma recovery scale-revised (CRS-R). The maximal peak frequency in the 1-14 Hz range successfully predicted both neurobehavioral capacity of patients as indicated by CRS-R total score and PDOC diagnosis. Additionally, in patients in whom only one peak within the 1-14 Hz range was observed, the AP gradient significantly contributed to the accuracy of prediction. We have identified three distinct spectral profiles of patients, likely representing separate neurophysiological modes of thalamocortical functioning. Etiology did not have significant influence on the obtained results.

Life satisfaction in families with a child in an Unresponsive Wakefulness Syndrome

Background

The article examines life conditions in families living together with a child in an Unresponsive Wakefulness Syndrome (UWS). Such families experience severe stress at financial, logistical, and existential level.

Methods

We investigated a large sample of families living with a UWS child (comprising 13% of the total population) and compared these families with families without a chronically ill child. A set of four questionnaires aimed to evaluate life conditions entails a total of 204 items. One of the questionnaires was developed by the corresponding author specifically for this study. The questionnaires were positively accepted by the persons concerned and permitted us to test six specific hypotheses.

Results

Life satisfaction (LS) in families with a UWS child was significantly lower than in control families. LS was significantly affected by external situational factors (everyday support, home visits, support by a doctor, nursing service, health insurance, etc.). Self-management skills were on average lower in families with a UWS child than in controls. These skills strongly and directly correlated with LS. Further, LS was not significantly related to the acceptance of feelings and negatively correlated with the floods of emotions. The relationship with the own child was equally satisfactory in families with and without a UWS child indicating that the families regard their UWS child as a full family member.

Conclusions

The data show that happy life is possible in families living together with a UWS child. They further specify conditions for satisfactory life under multiple highly severe challenges. Personal self-management skills, coping strategies, and resilience, as well as outside social support, appear to be critical factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02549-8.

Prognosis of patients in prolonged coma after severe carbon monoxide poisoning

BACKGROUND

Late recovery in patients following prolonged coma from carbon monoxide poisoning have been reported, but the probability is unclear. The purpose of this research was to assess the prognosis of patients in prolonged coma after severe carbon monoxide poisoning and related clinical and imaging features.

METHODS

There were 13 patients who had been in a state of coma for >7 days after acute carbon monoxide poisoning in the retrospective observational study, and demographic data, clinical data, laboratory data, complications, and image data were collected. Outcome was assessed by means of the Glasgow outcome scale after 1 year. The relationship between complications and imaging manifestations and prognosis was also analyzed.

RESULTS

One year after severe carbon monoxide poisoning, two patients (15.4%) had died (GOS 1), nine (69.2%) were in a persistent vegetative state (GOS 2), one (7.7%) was moderately disabled (GOS 4), and one (7.7%) achieved a good recovery (GOS 5) with minimal disability.

CONCLUSIONS

Most patients with prolonged coma after severe carbon monoxide poisoning had a poor prognosis, although the younger patients had a better prognosis. Respiratory failure, hypotension and renal failure during the course of the disease were associated with a poor prognosis. The prognosis of patients with injuries in two sites in early CT was poor. Multiple lesions (≥3) and extensive white matter damage (Fazekas grade (PVH or DWMH) = 3) on MRI of chronic phase were also associated with a poor prognosis.

Multidisciplinary attentive treatment for patients with chronic disorders of consciousness following severe traumatic brain injury in the NASVA of Japan

Primary Objective: The aim of this study was to demonstrate the clinical outcomes of long-term multidisciplinary attentive treatment (MAT) in patients with chronic disorders of consciousness (DOC) due to severe traumatic brain injury (TBI) following automotive accidents.Research Design: Five hundred and ten patients (mean age: 40.4 years) were enrolled in this retrospective study.Methods and Procedures: Patients were provided MAT for one to several years in the eight medical facilities of the National Agency for Automotive Safety and Victims' Aid (NASVA) in Japan. Clinical status for consciousness, communication, and activities of daily living were evaluated using the NASVA grading system.Outcomes and results: Following MAT, NASVA scores at discharge were significantly improved compared to those at admission in every patient subgroup including sex, age, NASVA score, and association with/without hypoxic encephalopathy at admission. Younger age, shorter interval between injury and admission, and better neurocognitive function at admission were found to be significant and independent factors for a good prognosis.Conclusions: MAT can partially improve the cognitive and physical abilities of patients with chronic DOC. From the perspective of not only restoring a patient's daily life, but also reducing the caregiver's burden, this type of treatment program warrants more public attention.

Longitudinal assessments highlight long-term behavioural recovery in disorders of consciousness

Accurate diagnosis and prognosis of disorders of consciousness is complicated by the variability amongst patients' trajectories. However, the majority of research and scientific knowledge in this field is based on cross-sectional studies. The translational gap in applying this knowledge to inform clinical management can only be bridged by research that systematically examines follow-up. In this study, we present findings from a novel longitudinal study of the long-term recovery trajectory of 39 patients, repeatedly assessed using the Coma Recovery Scale-Revised once every 3 months for 2 years, generating 185 assessments. Despite the expected inter-patient variability, there was a statistically significant improvement in behaviour over time. Further, improvements began approximately 22 months after injury. Individual variation in the trajectory of recovery was influenced by initial diagnosis. Patients with an initial diagnosis of unresponsive wakefulness state, who progressed to the minimally conscious state, did so at a median of 485 days following onset-later than 12-month period after which current guidelines propose permanence. Although current guidelines are based on the expectation that patients with traumatic brain injury show potential for recovery over longer periods than those with non-traumatic injury, we did not observe any differences between trajectories in these two subgroups. However, age was a significant predictor, with younger patients showing more promising recovery. Also, progressive increases in arousal contributed exponentially to improvements in behavioural awareness, especially in minimally conscious patients. These findings highlight the importance of indexing arousal when measuring awareness, and the potential for interventions to regulate arousal to aid long-term behavioural recovery in disorders of consciousness.

The effectiveness of non-invasive brain stimulation on arousal and alertness in patients in coma or persistent vegetative state after traumatic brain injury: Protocol of systematic review and network meta-analysis

BACKGROUND

Traumatic brain injury is a leading cause of death and disability worldwide. The survivors usually suffer from disorders of consciousness, especially coma state and persistent vegetative state. For these patients, there is no standard treatment for them, but non-invasive brain stimulations are considered as relatively more acceptable treatments. However, the knowledge regarding the relative effectiveness and the rank of the effectiveness of the non-invasive brain stimulations is limited. Thus, in this study, we aim to conduct a systematic review and network meta-analysis to evaluate the effect of non-invasive train stimulations on arousal and alertness in patients in a coma or persistent vegetative state after traumatic brain injury.

METHODS AND ANALYSIS

A comprehensive search strategy will be performed in the relevant databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Wan Fang Data). The random or quasi-random controlled trails focusing on the effectiveness of the non-invasive brain stimulations will be included. The risk of bias for the included studies will be appraised using the Cochrane collaboration tool for assessing risk of bias. The standard pairwise meta-analysis and a Bayesian network meta-analysis will be conducted.

ETHICS AND DISSEMINATION

This research is a systematic review and network meta-analysis. Thus, there is no requirement of ethical approval and patient informed consent.

PROSPERO REGISTRATION NUMBER

CRD42018104945.

Clinical characteristics and temporal profile of recovery in patients with favorable outcomes at 6 months after severe traumatic brain injury

OBJECTIVE Early withdrawal of life-sustaining treatment due to expected poor prognosis is responsible for the majority of in-house deaths in severe traumatic brain injury (TBI). With increased focus on the decision and timing of withdrawal of care in patients with severe TBI, data on early neurological recovery in patients with a favorable outcome is needed to guide physicians and families. METHODS The authors reviewed prospectively collected data obtained in 1241 patients with head injury who were treated between 1986 and 2012. Patients with severe TBI, motor Glasgow Coma Scale (mGCS) score < 6 on admission, and those who had favorable outcomes (Glasgow Outcome Scale [GOS] score of 4 or 5, indicating moderate disability or good recovery) at 6 months were selected. Baseline demographic, clinical, and imaging data were analyzed. The time from injury to the first record of following commands (mGCS score of 6) after injury was recorded. The temporal profile of GOS scores from discharge to 6 months after the injury was also assessed. RESULTS The authors studied 218 patients (183 male and 35 female) with a mean age of 28.9 ± 11.2 years. The majority of patients were able to follow commands (mGCS score of 6) within the 1st week after injury (71.4%), with the highest percentage of patients in this group recovering on Day 1 (28.6%). Recovery to the point of following commands beyond 2 weeks after the injury was seen in 14.8% of patients, who experienced significantly longer durations of intracranial pressure monitoring (p = 0.001) and neuromuscular blockade (p < 0.001). In comparison with patients with moderate disability, patients with good recovery had a higher initial GCS score (p = 0.01), lower incidence of anisocoria at admission (p = 0.048), and a shorter ICU stay (p < 0.001) and total hospital stay (p < 0.001). There was considerable improvement in GOS scores from discharge to follow-up at 6 months. CONCLUSIONS Up to 15% of patients with a favorable outcome after severe TBI may begin to follow commands beyond 2 weeks after the injury. These data caution against early withdrawal of life-sustaining treatment in patients with severe TBI.

Researching patients in the vegetative state: Difficulties of studying this patient group

It is now generally accepted that all patient groups should benefit from the potential advances in knowledge and understanding that result from clinical research. Despite this principle, patients in the vegetative state remain a group that has been chronically under-researched by neuroscientists because complex ethical questions and logistical dilemmas are raised by such research.

The vegetative state is one of the best known but least understood of neurological conditions. It affects a small but significant number of people who make a poor recovery after sustaining a brain injury and has been brought to public attention through high profile cases in the UK and the USA. This paper defines the vegetative state and explores four important issues that should be considered when planning clinical research in this field. It is demonstrated that not only is it possible to undertake such research but also that there needs to be more of it so that greater numbers of patients and their families will benefit.

Outcome Prediction of Consciousness Disorders in the Acute Stage Based on a Complementary Motor Behavioural Tool

INTRODUCTION

Attaining an accurate diagnosis in the acute phase for severely brain-damaged patients presenting Disorders of Consciousness (DOC) is crucial for prognostic validity; such a diagnosis determines further medical management, in terms of therapeutic choices and end-of-life decisions. However, DOC evaluation based on validated scales, such as the Revised Coma Recovery Scale (CRS-R), can lead to an underestimation of consciousness and to frequent misdiagnoses particularly in cases of cognitive motor dissociation due to other aetiologies. The purpose of this study is to determine the clinical signs that lead to a more accurate consciousness assessment allowing more reliable outcome prediction.

METHODS

From the Unit of Acute Neurorehabilitation (University Hospital, Lausanne, Switzerland) between 2011 and 2014, we enrolled 33 DOC patients with a DOC diagnosis according to the CRS-R that had been established within 28 days of brain damage. The first CRS-R assessment established the initial diagnosis of Unresponsive Wakefulness Syndrome (UWS) in 20 patients and a Minimally Consciousness State (MCS) in the remaining13 patients. We clinically evaluated the patients over time using the CRS-R scale and concurrently from the beginning with complementary clinical items of a new observational Motor Behaviour Tool (MBT). Primary endpoint was outcome at unit discharge distinguishing two main classes of patients (DOC patients having emerged from DOC and those remaining in DOC) and 6 subclasses detailing the outcome of UWS and MCS patients, respectively. Based on CRS-R and MBT scores assessed separately and jointly, statistical testing was performed in the acute phase using a non-parametric Mann-Whitney U test; longitudinal CRS-R data were modelled with a Generalized Linear Model.

RESULTS

Fifty-five per cent of the UWS patients and 77% of the MCS patients had emerged from DOC. First, statistical prediction of the first CRS-R scores did not permit outcome differentiation between classes; longitudinal regression modelling of the CRS-R data identified distinct outcome evolution, but not earlier than 19 days. Second, the MBT yielded a significant outcome predictability in the acute phase (p<0.02, sensitivity>0.81). Third, a statistical comparison of the CRS-R subscales weighted by MBT became significantly predictive for DOC outcome (p<0.02).

DISCUSSION

The association of MBT and CRS-R scoring improves significantly the evaluation of consciousness and the predictability of outcome in the acute phase. Subtle motor behaviour assessment provides accurate insight into the amount and the content of consciousness even in the case of cognitive motor dissociation.

Long-Term (Six Years) Clinical Outcome Discrimination of Patients in the Vegetative State Could be Achieved Based on the Operational Architectonics EEG Analysis: A Pilot Feasibility Study

Electroencephalogram (EEG) recordings are increasingly used to evaluate patients with disorders of consciousness (DOC) or assess their prognosis outcome in the short-term perspective. However, there is a lack of information concerning the effectiveness of EEG in classifying long-term (many years) outcome in chronic DOC patients. Here we tested whether EEG operational architectonics parameters (geared towards consciousness phenomenon detection rather than neurophysiological processes) could be useful for distinguishing a very long-term (6 years) clinical outcome of DOC patients whose EEGs were registered within 3 months post-injury. The obtained results suggest that EEG recorded at third month after sustaining brain damage, may contain useful information on the long-term outcome of patients in vegetative state: it could discriminate patients who remain in a persistent vegetative state from patients who reach a minimally conscious state or even recover a full consciousness in a long-term perspective (6 years) post-injury. These findings, if confirmed in further studies, may be pivotal for long-term planning of clinical care, rehabilitative programs, medical-legal decisions concerning the patients, and policy makers.

Care and neurorehabilitation in the disorder of consciousness: a model in progress

The operational model and strategies developed at the Institute S. Anna-RAN to be applied in the care and neurorehabilitation of subjects with disorders of consciousness (DOC) are described. The institute units are sequentially organized to guarantee appropriate care and provide rehabilitation programs adapted to the patients' clinical condition and individual's needs at each phase of evolution during treatment in a fast turnover rate. Patients eligible of home care are monitored remotely. Transferring advanced technology to a stage of regular operation is the main mission. Responsiveness and the time windows characterized by better residual responsiveness are identified and the spontaneous/induced changes in the autonomic system functional state and biological parameters are monitored both in dedicated sessions and by means of an ambient intelligence platform acquiring large databases from traditional and innovative sensors and interfaced with knowledge management and knowledge discovery systems. Diagnosis of vegetative state/unresponsive wakefulness syndrome or minimal conscious state and early prognosis are in accordance with the current criteria. Over one thousand patients with DOC have been admitted and treated in the years 1998–2013. The model application has progressively shortened the time of hospitalization and reduced costs at unchanged quality of services.

Descriptive characteristics and rehabilitation outcomes in active duty military personnel and veterans with disorders of consciousness with combat- and noncombat-related brain injury

OBJECTIVE

To report the injury and demographic characteristics, medical course, and rehabilitation outcome for a consecutive series of veterans and active duty military personnel with combat- and noncombat-related brain injury and disorder of consciousness (DOC) at the time of rehabilitation admission.

DESIGN

Retrospective study.

SETTING

Rehabilitation center.

PARTICIPANTS

From January 2004 to October 2009, persons (N=1654) were admitted to the Polytrauma Rehabilitation System of Care. This study focused on the N=122 persons admitted with a DOC. Participants with a DOC were primarily men (96%), on active duty (82%), ≥12 years of education, and a median age of 25. Brain injury etiologies included mixed blast trauma (24%), penetrating (8%), other trauma (56%), and nontrauma (13%). Median initial Glasgow Coma Scale score was 3, and rehabilitation admission Glasgow Coma Scale score was 8. Individuals were admitted for acute neurorehabilitation approximately 51 days postinjury with a median rehabilitation length of stay of 132 days.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Recovery of consciousness and the FIM instrument.

RESULTS

Most participants emerged to regain consciousness during neurorehabilitation (64%). Average gains ± SD on the FIM cognitive and motor subscales were 19 ± 25 and 7 ± 8, respectively. Common medical complications included spasticity (70%), dysautonomia (34%), seizure occurrence (30%), and intracranial infection (22%). Differential outcomes were observed across etiologies, particularly for those with blast-related brain injury etiology.

CONCLUSIONS

Despite complex comorbidities, optimistic outcomes were observed. Individuals with severe head injury because of blast-related etiologies have different outcomes and comorbidities observed. Health-services research with a focus on prevention of comorbidities is needed to inform optimal models of care, particularly for combat injured soldiers with blast-related injuries.

Do rehospitalization rates differ among injury severity levels in the NIDRR Traumatic Brain Injury Model Systems program?

OBJECTIVE

To compare the rate and nature of rehospitalization in a cohort of patients enrolled in the National Institute on Disability and Rehabilitation Research Traumatic Brain Injury Model Systems (TBIMS) who have disorders of consciousness (DOC) at the time of rehabilitation admission with those in persons with moderate or severe traumatic brain injury (TBI) but without DOC at rehabilitation admission.

DESIGN

Prospective observational study.

SETTING

Inpatient rehabilitation within TBIMS with annual follow-up.

PARTICIPANTS

Of 9028 persons enrolled from 1988 to 2009 (N=9028), 366 from 20 centers met criteria for DOC at rehabilitation admission and follow-up data, and another 5132 individuals met criteria for moderate (n=769) or severe TBI (n=4363).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Participants and/or their family members completed follow-up data collection including questions about frequency and nature of rehospitalizations at 1 year postinjury. For the subset of participants with DOC, additional follow-up was conducted at 2 and 5 years postinjury.

RESULTS

The DOC group demonstrated an overall 2-fold increase in rehospitalization in the first year postinjury relative to those with moderate or severe TBI without DOC. Persons with DOC at rehabilitation admission have a higher rate of rehospitalization across several categories than persons with moderate or severe TBI.

CONCLUSIONS

Although the specific details of rehospitalization are unknown, greater injury severity resulting in DOC status on rehabilitation admission has long-term implications. Data highlight the need for a longitudinal approach to patient management.

Prognostic Value of Resting-State Electroencephalography Structure in Disentangling Vegetative and Minimally Conscious States

Background. Patients in a vegetative state pose problems in diagnosis, prognosis, and treatment. Currently, no prognostic markers predict the chance of recovery, which has serious consequences, especially in end-of-life decision making. Objective. We aimed to assess an objective measurement of prognosis using advanced electroencephalography (EEG). Methods. EEG data (19 channels) were collected in 14 patients who were diagnosed to be persistently vegetative based on repeated clinical evaluations at 3 months following brain damage. EEG structure parameters (amplitude, duration, and variability within quasi-stationary segments, as well as the spatial synchrony between such segments and the strength of this synchrony) were used to predict recovery of consciousness 3 months later. Results. The number and strength of cortical functional connections between EEG segments were higher in patients who recovered consciousness ( P < .05 to P < .001) compared with those who did not recover. Linear regression analysis confirms that EEG structure parameters are capable of predicting ( P = .0025) recovery of consciousness 6 months postinjury, whereas the same analysis failed to significantly predict patient outcome based on aspects of their clinical history alone ( P = .629) or conventional EEG spectrum power ( P = .473). Conclusions. The result of this preliminary study demonstrates that structural strategy of EEG analysis is better suited for providing prognosis of consciousness recovery than existing methods of clinical assessment and of conventional EEG. Our results may be a starting point for developing reliable prognosticators in patients who are in a vegetative state, with the potential to improve their day-to-day management, quality of life, and access to early interventions.

Brain-derived neurotrophic factor (Val66Met) polymorphism does not influence recovery from a post-traumatic vegetative state: a blinded retrospective multi-centric study

Brain-derived neurotrophic factor (BDNF) is a neurotrophin that influences neuronal plasticity throughout life. Emergence from a vegetative state (VS) after a traumatic brain injury (TBI) implies that the brain undergoes plastic changes. A common polymorphism in the BDNF gene--BDNF Val66Met (referred to herein as BDNF(Met))--impairs cognitive function in healthy subjects. The aim of this study was to determine whether the BDNF(Met) polymorphism plays a role in the recovery of consciousness and cognitive functions in patients in a VS after a TBI. Fifty-three patients in a VS 1 month after a TBI were included in the study and genotyped for the BDNF(Met) polymorphism. Scores of levels of cognitive functioning (LCF) at 1, 3, 6, and 12 months post-TBI were retrospectively compared in patients without (Val group), and with (Met group), the BDNF(Met) polymorphism. The BDNF(Met) polymorphism was detected in 20 out of the 53 patients. The mean LCF scores in the Val and Met groups were 1.6±0.5 and 1.4±0.5 at 1 month, 2.3±0.7 and 2.5±1.2 at 3 months, 3.3±1.7 and 3.5±1.7 at 6 months, and 4±1.9 and 3.9±1.8 at 12 months, respectively (p>0.05). The percentages of patients in the Val and Met groups who emerged from the VS were 36.4% and 30% at 3 months, 66.3% and 70% at 6 months, and 70% and 87.5% at 12 months (p>0.05), respectively. These findings provide evidence that the BDNF(Met) polymorphism is not involved in cognitive improvement in patients with a VS following TBI. Future studies should focus on the role of other BDNF polymorphisms in the recovery from a VS.

Comparison of the Full Outline of UnResponsiveness and Glasgow Liege Scale/Glasgow Coma Scale in an intensive care unit population

BACKGROUND

The Full Outline of UnResponsiveness (FOUR) has been proposed as an alternative for the Glasgow Coma Scale (GCS)/Glasgow Liège Scale (GLS) in the evaluation of consciousness in severely brain-damaged patients. We compared the FOUR and GLS/GCS in intensive care unit patients who were admitted in a comatose state.

METHODS

FOUR and GLS evaluations were performed in randomized order in 176 acutely (<1 month) brain-damaged patients. GLS scores were transformed in GCS scores by removing the GLS brainstem component. Inter-rater agreement was assessed in 20% of the studied population (N = 35). A logistic regression analysis adjusted for age, and etiology was performed to assess the link between the studied scores and the outcome 3 months after injury (N = 136).

RESULTS

GLS/GCS verbal component was scored 1 in 146 patients, among these 131 were intubated. We found that the inter-rater reliability was good for the FOUR score, the GLS/GCS. FOUR, GLS/GCS total scores predicted functional outcome with and without adjustment for age and etiology. 71 patients were considered as being in a vegetative/unresponsive state based on the GLS/GCS. The FOUR score identified 8 of these 71 patients as being minimally conscious given that these patients showed visual pursuit.

CONCLUSIONS

The FOUR score is a valid tool with good inter-rater reliability that is comparable to the GLS/GCS in predicting outcome. It offers the advantage to be performable in intubated patients and to identify non-verbal signs of consciousness by assessing visual pursuit, and hence minimal signs of consciousness (11% in this study), not assessed by GLS/GCS scales.

Longitudinal outcome of patients with disordered consciousness in the NIDRR TBI Model Systems Programs

Few studies address the course of recovery from prolonged disorders of consciousness (DOC) after severe traumatic brain injury (TBI). This study examined acute and long-term outcomes of persons with DOC admitted to acute inpatient rehabilitation within the National Institute on Disability and Rehabilitation Research (NIDRR) TBI Model Systems Programs (TBIMS). Of 9028 persons enrolled from 1988 to 2009, 396 from 20 centers met study criteria. Participants were primarily male (73%), Caucasian (67%), injured in motor vehicle collision (66%), with a median age of 28, and emergency department Glasgow Coma Scale (GCS) score of 3. Participant status was evaluated at acute rehabilitation admission and discharge and at 1, 2, and 5 years post-injury. During inpatient rehabilitation, 268 of 396 (68%) regained consciousness and 91 (23%) emerged from post-traumatic amnesia (PTA). Participants demonstrated significant improvements on GCS (z=16.135, p≤0.001) and Functional Independence Measure (FIM) (z=15.584, p≤0.001) from rehabilitation admission (median GCS=9; FIM=18) to discharge (median GCS=14; FIM=43). Of 337 with at least one follow-up visit, 28 (8%) had died by 2.1 years (mean) after discharge. Among survivors, 66 (21%) improved to become capable of living without in-house supervision, and 63 demonstrated employment potential using the Disability Rating Scale (DRS). Participants with follow-up data at 1, 2, and 5 years post-injury (n=108) demonstrated significant improvement across all follow-up evaluations on the FIM Cognitive and Supervision Rating Scale (p<0.01). Significant improvements were observed on the DRS and FIM Motor at 1 and 2 years post-injury (p<0.01). Persons with DOC at the time of admission to inpatient rehabilitation showed functional improvement throughout early recovery and in years post-injury.

Deep brain stimulation for the treatment of vegetative state

One hundred and seven patients in vegetative state (VS) were evaluated neurologically and electrophysiologically over 3 months (90 days) after the onset of brain injury. Among these patients, 21 were treated with deep brain stimulation (DBS). The stimulation sites were the mesencephalic reticular formation (two patients) and centromedian-parafascicularis nucleus complex (19 cases). Eight of the patients recovered from VS and were able to obey verbal commands at 13 and 10 months in the case of head trauma and at 19, 14, 13, 12, 12 and 8 months in the case of vascular disease after comatose brain injury, and no patients without DBS recovered from VS spontaneously within 24 months after brain injury. The eight patients who recovered from VS showed desynchronization on continuous EEG frequency analysis. The Vth wave of the auditory brainstem response and N20 of the somatosensory evoked potential could be recorded, although with a prolonged latency, and the pain-related P250 was recorded with an amplitude of > 7 μV. Sixteen (14.9%) of the 107 VS patients satisfied these criteria in our electrophysiological evaluation, 10 of whom were treated with DBS and six of whom were not treated with DBS. In these 16 patients, the recovery rate from VS was different between the DBS therapy group and the no DBS therapy group (P < 0.01, Fisher's exact probability test) These findings indicate that DBS may be useful for the recovery of patients from VS if the candidates are selected on the basis of electrophysiological criteria.

Cognitive rehabilitation following traumatic brain injury

Annually, some 500,000 people are hospitalized with brain lesions acquired after traumatic brain injury (TBI) in Brazil. Between 75,000 and 100,000 individuals die within hours of the event and 70,000 to 90,000 evolve to irreversible loss of some neurological function. The principal causes of TBI include motor vehicle accidents (50%), falls (21%), assaults and robberies (12%) and accidents during leisure activities (10%). Within this context, cognitive rehabilitation, a clinical area encompassing interdisciplinary action aimed at recovery as well as compensation of cognitive functions altered as a result of cerebral injury, is extremely important for these individuals. Therefore, the aim of this study was to review the basic concepts related to TBI, including mechanisms of injury, severity levels of TBI, the most common findings in moderate and severe TBI survivors, and the most frequent cognitive impairments following TBI, and also to discuss the strategies used to handle patients post-TBI. The study results yielded relevant information on a structured cognitive rehabilitation service, representing an alternative for patients and families afflicted by TBI, enabling the generation of multiple research protocols.

Persistent vegetative and minimally conscious states

The diagnosis and management of patients with persistent vegetative (PVS) and minimally conscious (MCS) states entail powerful medical, ethical and legal debates. The recent description of the MCS highlights the crucial role of unexpected and well-documented recoveries of cognitive functions. Functional neuroimaging has provided new insights for assessing neuropathology and cerebral activity in these patients, providing information on the presence, degree, and location of any residual brain function in patients with PVS or MCS. We present a review on this topic, emphasizing the clinical and neuroimaging assessment of these states, with some of our recent results in this area. We conclude that the development of rehabilitation techniques for patients with PVS and others suffering long-lasting effects of brain injury is a crucial challenge for actual and future generations of neuroscientists.

Care protocol for persistent vegetative states (PVS) and minimally conscious state (MSC) in Lorraine: retrospective study over an 18-year period

OBJECTIVES

Retrospective analysis of the efficiency of a protocol for care of chronic vegetative states (CVS) and minimally conscious state (MCS) in Lorraine.

MATERIAL AND METHOD

Two indicators are used: protocol activity (number of patients hospitalized between 1988 and 2006, number of admissions per year, of requests per year, origin of requests, waiting time) and the epidemiological data (age, sex ratio, etiology, length of stay, geographic origin, number of deaths, number of hospital discharges). The number of CVS and MCS and patients having progressed towards arousal is specified as well as the technical procedures (orthopedic surgery, number of tracheotomies).

RESULTS

Forty-seven patients (30 males and 17 females) were hospitalized in a 12-bed unit. The number of admissions per year was 2.4, and the annual number of requests varied between five and 15. Hospitalization times ranged from six to 18 months. The average length of hospitalization was 41 months. Eighty-eight percent of the cases were residents of Lorraine. The etiology was traumatic (53%), vascular (38% including 12% anoxia), miscellaneous (9%). Fifteen percent rate of return to arousal (average time period: 28.41 months, traumatic etiology) with hospital discharge in four cases.

CONCLUSION

The protocol is managed as part of a local scheme and enables an appropriate response to a specific clinical profile by providing up-to-date multidiscipline follow-up care and a rapid solution should intercurrent events occur (signs of arousal, orthopedic deterioration, change of environment). Typical limitations are geographical remoteness and difficulties with family support care.

Residual Brain Processing in the Vegetative State

Vegetative state (VS) is a clinical condition in the severely brain damaged, characterized by wakefulness but unaccompanied by any evidence of awareness of self or environment, voluntary or purposeful behavioral responses to external stimuli, and communication. A metabolic dysfunction of the frontal-parietal network is thought to be responsible for the “functional disconnection” underlying it. Most subjects recover with or without residual disabilities depending on the extent of brain damage. However, VS persists for over 1 year in about 15% of all cases, with exceptional later recovery; prolonged observation has thus become possible and our perspectives have expanded substantially. In recent years, brain activation in response to painful or emotional stimuli (e.g., the mother’s voice or presence) or under stimulus conditions implying processing at varying levels of functional complexity (including learning and semantic functions) has been documented in unambiguously diagnosed VS subjects by advanced electrophysiological and neuroimaging techniques. Methods, experimental conditions, and the results of studies published in years 2002–2008 are summarized. The extent to which brain activation concomitant to external events reflect brain function remains to be investigated. Today, VS nevertheless appears neither static nor homogeneous. An updated characterization also taking the evidence of residual brain responsiveness into account is due. Research with advanced technologies and sophisticated paradigms of brain activation in VS may help us to understand the basic neural processes underlying human consciousness.

Clinical signs and early prognosis in vegetative state: a decisional tree, data-mining study

BACKGROUND AND PURPOSE

Residual brain function has been documented in vegetative state patients, yet early prognosis remains difficult. The purpose of this study was to identify by artificial intelligence procedures (classification and regression trees, data-mining) the significant neurological signs correlated to and predictive of outcome.

METHODS

Three hundred and thirty-three patients in vegetative state of traumatic or non-traumatic aetiology referred to the S.Anna Institute were retrospectively studied. Twenty-two neurological signs were assessed according to criteria included in the UNI ENI ISO 9001 : 2000 quality standards at admission (Time(0)) and after 50, 100 or 180 days and entered into a CART (classification and regression tree) data-mining procedure with a decisional tree j48 (Weka software and 10-fold cross-validation). Outcome was conventionally rated by the Glasgow outcome scale.

RESULTS AND CONCLUSIONS

Re-appearance with proper timing of spontaneous motility, eye tracking and oculo-cephalic reflex and disappearance of oral automatisms proved highly correlated to outcome and allowed early and reliable prognosis. These findings are consistent with the brain functional organization thought to sustain consciousness and warrant systematic investigation. Classification and regression trees and data-mining procedures proved applicable in neurology to sort out significant clinical signs also in clinical conditions characterized by paucity of signs such as the vegetative state. Extended application in clinical medicine is conceivable based on the approach peculiarities.

The vegetative state: a report of two cases with a long-term follow-up

OBJECTIVES

To demonstrate that patients with Prolonged Vegetative State (PVS) can show signs of improvements and important changes and, consequently, to strengthen the necessity to evaluate them with long-term serial follow-ups.

SETTING

Rehabilitation of patients with severe traumatic brain injury (TBI).

PARTICIPANTS

Two people with severe TBI discharged after a long period of inpatient rehabilitation in a condition of PVS.

RESULTS

After 5 years some important changes happened and the initial prognosis was proved to be wrong.

CONCLUSION

Sometimes patients declared to be in PVS have the possibility to recover, especially when initial clinical conditions are particularly severe and do not allow the emergence of the state of consciousness. It is important to conduct regular follow-ups to better evaluate changes and, if it is necessary, to re-adjust the rehabilitation accordingly.

Chronic disorders of consciousness

The vegetative state and the minimally conscious state are disorders of consciousness that can be acute and reversible or chronic and irreversible. Diffuse lesions of the thalami, cortical neurons, or the white-matter tracts that connect them cause the vegetative state, which is wakefulness without awareness. Functional imaging with PET and functional MRI shows activation of primary cortical areas with stimulation, but not of secondary areas or distributed neural networks that would indicate awareness. Vegetative state has a poor prognosis for recovery of awareness when present for more than a year in traumatic cases and for 3 months in non-traumatic cases. Patients in minimally conscious state are poorly responsive to stimuli, but show intermittent awareness behaviours. Indeed, findings of preliminary functional imaging studies suggest that some patients could have substantially intact awareness. The outcomes of minimally conscious state are variable. Stimulation treatments have been disappointing in vegetative state but occasionally improve minimally conscious state. Treatment decisions for patients in vegetative state or minimally conscious state should follow established ethical and legal principles and accepted practice guidelines of professional medical specialty societies.

The vegetative state and the Royal College of Physicians guidance

The Royal College of Physicians of the UK, together with the Colleges of Edinburgh and Glasgow, have produced guidance on the diagnosis and management of people in the vegetative state (report of a working party of the Royal College of Physicians, 2003). Such guidance is important when the single criterion for awareness in an individual is the perception of that awareness by a potentially fallible observer. The current guidance is reviewed and comparisons made with existing arrangements in other countries. Consideration is given to the possibility of future improvements in diagnosis with the advent of imaging and metabolic assessments of brain function and the need to define the required qualifications and training for those "experts" who are currently involved in the diagnosis of the vegetative state.

Epidemiology and prognosis of coma in daytime television dramas

OBJECTIVE

To determine how soap operas portray, and possibly misrepresent, the likelihood of recovery for patients in coma.

DESIGN

Retrospective cohort study.

SETTING

Nine soap operas in the United States reviewed between 1 January 1995 and 15 May 2005.

SUBJECTS

64 characters who experienced a period of unconsciousness lasting at least 24 hours. Their final status at the end of the follow-up period was compared with pooled data from a meta-analysis.

RESULTS

Comas lasted a median of 13 days (interquartile range 7-25 days). Fifty seven (89%) patients recovered fully, five (8%) died, and two (3%) remained in a vegetative state. Mortality for non-traumatic and traumatic coma was significantly lower than would be predicted from the meta-analysis data (non-traumatic 4% v 53%; traumatic 6% v 67%; Fisher's exact test both P < 0.001). On the day that patients regained consciousness, most (49/57; 86%) had no evidence of limited function, cognitive deficit, or residual disability needing rehabilitation. Compared with meta-analysis data, patients in this sample had a much better than expected chance of returning to normal function (non-traumatic 91% v 1%; traumatic 89% v 7%; both P < 0.001).

CONCLUSIONS

The portrayal of coma in soap operas is overly optimistic. Although these programmes are presented as fiction, they may contribute to unrealistic expectations of recovery.

Spontaneous blinking behaviour in persistent vegetative and minimally conscious states: Relationships with evolution and outcome

There is evidence that spontaneous blinking correlates with cognitive functions. This arises from the observation that blinking rate (BR) is modulated by arousal levels, basic cognitive processes (e.g., attention, information processing, memory, etc.) and more complex cognitive functions (e.g., reading, speaking, etc.). The aim of this work was to test the role of BR evaluation in the assessment of cognitive network functioning in awake patients with consciousness deficits. Thirteen patients were recruited for the study, and were assessed by the Glasgow coma scale (GCS) and Glasgow outcome scale (GOS) on admittance and discharge, respectively. A level of cognitive functioning scale (LCFS) score was assigned at every change in awareness or at least every 2 weeks. At the same time as the clinical tests, the BR was observed for a 5-min period. Ten healthy subjects, observed throughout three non-consecutive days, formed the control group. The BR underwent a different temporal behaviour in the two diagnostic categories. In the persistent vegetative state (PVS) group it remained stable throughout time and linked with the clinical conditions of the patients; whereas in the non-persistent vegetative state (NPVS) group it decreased over time as the cognitive conditions improved. Moreover, a strong inverse correlation was found between overall BR values and LCFS scores. We have concluded that the blinking behaviour changes manifested in PVS and NPVS patients reflect different evolution phases of a cholinergic-dopaminergic imbalance, and that a reduced BR characterizes the early stages of consciousness recovery.

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.

[How can we define the modalities and clinical levels of coma to wakefulness?]

OBJECTIVE

The starting point of the French conference of consensus concerning arousal after coma was to answer the following question: "How can we define the ways of going from coma to arousal and their clinical levels?

MATERIALS AND METHOD

A team of readers have picked up in the literature one hundred and fifty papers, out of which fifty six have been analysed.

RESULTS

From this analysis, three points emerged: The concepts of coma and arousal; The conditions of evolution from coma to arousal; Various groups of patients depending on their expressing arousal. One could not find any consensual model concerning the different ways of going from coma to arousal. The variability of the technics and the changing validity of all scores did not allow the conditions of arousal to reach a satisfactory level of proof. The Glasgow Coma Scale (GCS) is the recognised standard for severe wakefulness' impairment, but it is not sensitive enough while patients' arousing. The Glasgow Outcome Scale (GOS) takes into account the patients' situations far later and does not include situations such as Minimally Conscious States (MCS). That's why we face multiple scores, either ordinal, or categorial, all tending to evaluate the slow levels of arousal.

CONCLUSION

Clinical findings concerning arousal are to be completed by non-clinical data. This would be greatly helpful to define appropriate management concerning individualized groups of patients. At this stage, another challenge for clinicians is to make the difference between emerging wakefulness and growing conscious activity.

Prediction of recovery from post-traumatic vegetative state with cerebral magnetic-resonance imaging

BACKGROUND

The early post-traumatic vegetative state (VS) is compatible with recovery. Various clinical and laboratory tests have failed to predict recovery so we assessed the value of cerebral magnetic-resonance imaging (MRI) in prediction of recovery.

METHODS

80 adult patients in post-traumatic VS had cerebral MRI between 6 weeks and 8 weeks after injury. MRIs were reviewed by three neuroradiologists for the number, sizes, and location of brain lesions. Three neurologists assessed the patients at the time of MRI and at 2 months, 3 months, 6 months, 9 months, and 12 months after injury using the Glasgow Outcome Scale.

FINDINGS

At 12 months, 38 patients had recovered while 42 patients remained in the VS. The demographic characteristics and causes and severity of injury were similar in patients in persistent VS (PVS) and those who recovered (NPVS). An average of 6.1 different brain areas were injured in patients in PVS compared with 4.6 areas in patients who had NPVS. Patients in PVS revealed a significantly higher frequency of corpus callosum, corona radiata, and dorsolateral brainstem injuries than did patients who recovered. Logistic regression analysis showed that corpus callosum and dorsolateral brainstem injuries were predictive of non-recovery. The adjusted odds ratios for non-recovery of patients with a corpus callosum lesion and dorsolateral brainstem injury were 213.8 (95% CI 14.2-3213.3), and 6.9 (11-42.9), respectively. In contrast, clinical characteristics, such as initial score on the Glasgow Coma Scale, age, and pupillary abnormalities failed to predict recovery.

INTERPRETATION

Cerebral MRI findings in the subacute stage after head injury can predict the outcome of the post-traumatic VS. Corpus callosum and dorsolateral brainstem lesions are highly significant in predicting non-recovery.

Persistent vegetative state: clinical and ethical issues

Coma, vegetative state, lock-in syndrome and akinetic mutism are defined. Vegetative state is a state with no evidence of awareness of self or environment and showing cycles of sleep and wakefulness. PVS is an operational definition including time as a variable. PVS is a vegetative state that has endured or continued for at least one month. PVS can be diagnosed with a reasonable amount of medical certainty; however, the diagnosis of PVS must be kept separate from the outcome. The patient outcome can be predicted based on etiology and age. Using outcome probabilities and etiology as criteria, patients can be subdivided in 5 groups and reasonable management guidelines can be suggested. Three levels of care can be provided to PVS patients: high technology, supportive and compassionate care. Pragmatic options for the various subgroups of patients are suggested. Management decisions will remain difficult for both the family and the health-care team. The role of the physician in these difficult cases is to share the decision-making with the family.

Post-traumatic apallic syndrome following head injury. Part 2: Treatment

There is no doubt that vegetative patients need the appropriate medical and nursing procedures as well as family involvement, education and counselling. Additional structured stimulation programmes are used for the treatment of coma and vegetative state. The theoretical foundation is derived from animal studies. The relevance of the results for the rehabilitation of head-injured human patients remains questionable, because all animal studies involve the use of cerebral lesions different from those found in human head-injured patients. The studies of human sensory stimulation give more an orientation than a definitive statement. Very recently, hypotheses concerning sensory regulation have begun to be evaluated. Further investigations are required to provide a more definite conclusion.

Post-traumatic apallic syndrome following head injury. Part 1: clinical characteristics

Epidemiological studies made within the western countries indicate an incidence of 200-300 traumatic head injuries per 100 000 residents each year. Severe head injuries account for 5-25% of all head injuries; 10-14% of all severe head-injured patients develop into a vegetative state, in which a sleep-wake rhythm is apparent, but however in which there is no evidence of awakeness or reactivity to the environment. The most commonly used labels, in the German and international literature, for these patients are 'vegetative state', 'apallic syndrome' and 'coma vigile'. This clinical characterization is not sufficient. It is necessary to employ additional criteria to distinguish subsets of vegetative patients e.g. computerized tomography, magnetic resonance imaging, single photon emission tomography, electroencephalography, brainstem reflexes, evoked potentials, assessment scales, age, premorbid brain disorders. Diagnostic and prognostic parameters must form the basis for various decisions relating to patients' care and intervention.

Event-related potentials--neurophysiological tools for predicting emergence and early outcome from traumatic coma

OBJECTIVE

To determine the prognostic value of multimodal evoked potentials (EPs) and event-related (ERPs) potentials in coma (Glasgow Coma Score <8), after severe traumatic brain injury (TBI).

DESIGN

Prospective, longitudinal study of neurophysiological responses recorded during traumatic coma.

SETTING

Intensive Care Unit, Frenchay Hospital, Bristol, UK.

PARTICIPANTS

Fifty-four comatose TBI patients (age range 1-80 years, mean 36.4).

METHODS

Neurophysiological responses were recorded from 11 scalp electrodes with earlobe reference. Conduction times were measured for brainstem auditory, flash visual and somatosensory, short-latency EPs. Peak latencies and amplitudes were determined for long-latency components of visual and auditory ERPs, generated by passive "oddball" paradigms. These neurophysiological and various clinical parameters were correlated with patient outcome using Pearson's coefficient.

MAIN OUTCOME MEASURE

Three month Glasgow Outcome Scale (GOS).

RESULTS AND CONCLUSION

Highly significant (P <0.001) correlations exist between long-latency ERP components and 3-month outcome. Short-latency EPs, brainstem (wave I-V) and somatosensory conduction times also correlate significantly with the GOS (P <0.01). Of the clinical measurements, pupillary response patterns, APACHE II and Glasgow Coma Scores (GCS) correlate significantly with outcome, as do the retrospective measures of duration of coma and post-traumatic amnesia (PTA) in survivors. Unfortunately, due to variance of long-latency responses, even in controls, absolute values cannot be relied upon as prognosticators. The presence of "mismatch negativity" predicted the return of consciousness (89.7% sensitivity and 100% specificity) and preceded changes in GCS. Its latency was the single best indicator of 90-day outcome from coma (r = -0.641).

Assessment of vision and visual attention in minimally responsive brain injured patients

Sensory, motor, and cognitive assessment is a critical priority in the care of minimally responsive brain-injured patients. However, their inconsistent pattern of responding may interfere with the use of traditional forms of assessment such as the mental status or neurological examinations. In this article we describe a quantitative method, based on single-subject experimental design, for evaluating vision and visual attention in this patient population. In a series of randomized trials, combinations of a blank card, a colorful photograph, and no stimulus are presented to either or both visual fields while horizontal eye movements are observed. The relationship between the side and nature of the visual stimulus and the frequency of eye movements is analyzed to determine visual function in one or both eyes. We report six cases of minimally responsive patients assessed with this method. In case A, we show evidence of functional vision in both visual fields. Case B also shows functional fields, but with a monocular visual deficit. Cases C and D show a homonymous hemianopsia which, in case D, is further complicated by a monocular visual deficit. Finally, cases E and F show patterns of left and right visual extinction. Thus, this objective and quantitative method leads to conclusions about patients' visual function that are not readily apparent by clinical observation and that allow appropriate modifications in further assessment or treatment.

Outcome of post-traumatic unawareness persisting for more than a month

From 1986 to the end of 1991, 19 patients with persisting post-traumatic unawareness were admitted for rehabilitation. Criteria for admission were head trauma, Glasgow coma scale score < or = 8 points, and at least a one month duration of unawareness. Out of 19 patients, 12 patients (63%) regained consciousness, 11 patients (58%) within the first year and one patient (5%) within the second year. The mean duration of unawareness in the patients who recovered consciousness was 190 (range 62-440) days. In the recovery group, according to the Glasgow outcome scale, seven out of 12 patients (58%) were moderately disabled and five (42%) were severely disabled at the moment of discharge from rehabilitation. All the 12 patients who regained consciousness live with their families, and none had to be kept in an institution. The data confirm that awakening from post-traumatic unawareness is possible after a long period. Therefore, post-traumatic unawareness persisting for more than a month should not be considered an irreversible condition, because an outcome that might be regarded by some as being acceptable is possible even in patients with very severe brain damage.

Recommendations for use of uniform nomenclature pertinent to patients with severe alterations in consciousness. American Congress of Rehabilitation Medicine

There continues to be considerable confusion and controversy on the use of diagnostic and clinical terms assigned to patients with severe alterations in consciousness. This confusion results largely from the lack of a uniform classification system that is based on behaviorally defined criteria. This position paper provides recommendations for defining coma, vegetative state (including persistent and permanent vegetative state), akinetic mutism, the minimally responsive state, and locked-in syndrome based on neurobehavioral and neuropathologic features. Current controversies surrounding use of these terms also are discussed.

A right to die?

Often nurses within the critical care setting face moral dilemmas when confronted with issues surrounding resuscitation and withdrawal of treatment. In this article the nurses' role and the patients' rights regarding resuscitative measures and withdrawal of basic and advanced forms of life support are discussed. Cases that have improved decision-making have been used to illustrate the dilemmas involved. It is hoped that critical care nurses will become more aware of their vital role when these decisions are being made.