Posttraumatic Amnesia as a predictor of outcome after severe closed head injury. Prospective assessment

Prognostic value of demographic characteristics in traumatic brain injury: results from the IMPACT study

Outcome following traumatic brain injury (TBI) is not only dependent on the nature and severity of injury and subsequent treatment, but also on constituent characteristics of injured individuals. We aimed to describe and quantify the relationship between demographic characteristics and six month outcome assessed by the Glasgow Outcome Scale (GOS) after TBI. Individual patient data on age (n = 8719), gender (n = 8720), race (n = 5320), and education (n = 2201) were extracted from eight therapeutic Phase III randomized clinical trials and three surveys in moderate or severe TBI, contained in the IMPACT database. The strength of prognostic effects was analyzed with binary and proportional odds regression analysis and expressed as an odds ratio. Age was analyzed as a continuous variable with spline functions, and the odds ratio calculated over the difference between the 75 th and 25 th percentiles. Associations with other predictors were explored. Increasing age was strongly related to poorer outcome (OR 2.14; 95% CI 2.00-2.28) in a continuous fashion that could be approximated by a linear function. No gender differences in outcome were found (OR: 1.01; CI 0.92-1.11), and exploratory analysis failed to show any gender/age interaction. The studies included predominantly Caucasians (83%); outcome in black patients was poorer relative to this group (OR 1.30; CI 1.09-1.56). This relationship was sustained on adjusted analyses, and requires further study into mediating factors. Higher levels of education were weakly related to a better outcome (OR: 0.70; CI 0.52-0.94). On multivariable analysis adjusting for age, motor score, and pupils, the prognostic effect of race and education were sustained. We conclude that outcome following TBI is dependent on age, race, to a lesser extent on education, but not on gender.

"Galveston Orientation and Amnesia Test": tradução e validação

OBJETIVO: Traduzir e validar o Galveston Orientation and Amnesia Test para uso em nosso meio. MÉTODOS: Esse teste foi traduzido para o português e retro-traduzido para o inglês por diferentes especialistas na língua e por fim, feita a avaliação da equivalência entre o instrumento original e a versão retro-traduzida. Sua aplicação em 73 vítimas de trauma crânio-encefálico contuso e a indicação da gravidade dessa lesão, estabelecida pela Escala de Coma de Glasgow, permitiram verificar as propriedades de medida do instrumento. RESULTADOS: A confiabilidade verificada pelo Alfa de Cronbach resultou em 0,76. Houve indicação de validade convergente e discriminante do instrumento quando os resultados de aplicação do Galveston Orientation and Amnésia Test foram analisados perante a gravidade do trauma crânio-encefálico. CONCLUSÃO: Os resultados observados dão suporte para a aplicação do Galveston Orientation and Amnesia Test em nosso meio como indicador do término da amnésia pós-traumática.

Prediction of Outcome at Discharge From Acute Care Following Traumatic Brain Injury

OBJECTIVE

To compute outcome probabilities for persons with traumatic brain injury at discharge from acute care.

PARTICIPANTS

Three hundred thirty-nine patients with traumatic brain injury (239 mild, 48 moderate, 52 severe).

SETTING

Level I trauma center.

MAIN MEASURES

Predictor variables considered were age, education, Glasgow Coma Scale score, duration of posttraumatic amnesia, cerebral imaging results, and need for neurosurgical intervention. Outcome measures were Extended Glasgow Outcome Scale and discharge destination.

RESULTS

Logistic regressions showed that a shorter posttraumatic amnesia decreased the probability of moderate to severe disability. Moreover, discharge home was less probable for patients with positive cerebral imaging.

CONCLUSION

This model can help predict rehabilitation needs upon discharge from an acute care hospital.

A Review of the Literature on Orientation as an Indicator of Level of Consciousness

PURPOSE

To review and compare the concepts of orientation and level of consciousness.

METHODS

Literature review, including studies of orientation as an indicator of level of consciousness, in the domains of nursing, medicine, and neuropsychology.

FINDINGS

Orientation to time, place, and person as a measure of level of consciousness is poorly understood. The nursing practice of assessing orientation is common in many practice settings, yet little research has been done to validate whether it is meaningful.

CONCLUSIONS

This review lays important groundwork for future evidence-based research into the use of orientation as an indicator of level of consciousness.

Prediction of global outcome with acute neuropsychological testing following closed-head injury

Delaying assessment until emergence from post-traumatic amnesia increases completion rates, but this practice causes variable time delays from the date of injury to testing, which can complicate the interpretation of research findings. In the current study, the performance of 105 head injury survivors on simple tests of language comprehension and attention was used to predict global outcome. It was hypothesized that 1 month performance on these measures would aid in the prediction of Disability Rating Scale (DRS) and Glasgow Outcome Scale (GOS) scores collected at 6 months post injury. Only raw scores on the modified Test of Complex Ideational Material accounted for a significant amount of the variance in DRS scores (4.4%) above that accounted for by age, education, Glasgow Coma Scale score, and pupil response. However, testability at 1 month post injury on all four tests consistently accounted for a larger portion of the variance in DRS scores (10.1-13.2%) and significantly improved prediction of GOS scores. Galveston Orientation and Amnesia Test scores collected at 1 month post injury accounted for substantially less variance in DRS scores (7.7-8.4%). Neuropsychological data, including the testability of patients, collected uniformly at 1 month following injury can contribute to the prediction of global outcome.

[Prognostic factors in severe head injury]

The knowledge of the so called prognostic factors or indicators involved in severe head injury (SHI) is an issue of great interest to make predictions about the future of patients with this pathology. Those indicators constitute the basic elements of the different prognostic formulas or models carried out in order to make predictions in SHI. The mentioned models, therefore, will be constructed by a group of variables (prognostic indicators or factors) and several scales (prognostic scales) that are useful for measuring the final outcome of these patients. In this paper we resume, after an exhaustive review of the literature, the knowledge about the prognostic factors related to SHI. These indicators have been classified as follows: clinical, radiological, physiological, and biochemical. Moreover, we have briefly described the prognostic scales more commonly used in SHI.

Influence of Extraneurological Insults on Ventricular Enlargement and Neuropsychological Functioning after Moderate and Severe Traumatic Brain Injury

Extraneurological insults secondary to TBI such as hypotension or hypoxia have been associated with mortality and morbidity. The purpose of this study was to investigate the influence of systemic complications on both neuropsychological outcome and cerebral atrophy. Fifty-seven patients selected from 122 consecutive admissions were studied. Data on the type and severity of injury as well as other systemic insults were collected prior to and during the first 3 days of hospitalization. These data included the presence or absence of a hypoxic episode during the pre-hospital period, the presence and degree of hypoxia, hypercapnia, anemia, hypotension and intracranial hypertension, pupillary reactivity, Glasgow Coma Scale score and coma duration. From the last control CT scan image, performed 6 months post-injury, four different indexes of ventricular dilatation were calculated. Neuropsychological assessment at 6 months included tests of verbal and visual memory, visuoconstructive functions, fine motor speed, and frontal lobe functions. Our results showed that hypoxia and hypotension were related to neuropsychological outcome and long-term ventricular enlargement. Hypoxic episodes prior to hospitalization were related to third ventricle dilatation and to adverse neurological and cognitive outcomes, especially to attention, motor speed, mental flexibility, fluency and verbal memory impairments, suggesting fronto-striatal and hippocampal dysfunction. We conclude that the effect of extraneurological insults on brain structure and function may be as important as the severity of the primary injury.

The relation between memory of the traumatic event and PTSD: evidence from studies of traumatic brain injury

OBJECTIVE

This paper focuses on the relation between memory and posttraumatic stress disorder (PTSD). More specifically, it addresses the debate regarding the role of memory of the traumatic event in the development of PTSD. Traumatic brain injury (TBI) is used as a naturally occurring model for traumatic exposure that is often associated with memory impairment.

METHOD

We present a critical review of the literature on studies assessing the relation between TBI and PTSD, with a focus on memory of the traumatic event as a critical factor. We also discuss results from recent studies conducted by our group.

RESULTS

The literature review offers an inconclusive picture wherein a significant proportion of the studies indicate that PTSD and TBI are mutually exclusive, especially in individuals who exhibit lack of memory for the traumatic event. This finding supports the possibility that lack of memory may protect against the development of PTSD. However, some studies show that PTSD does occur in patients with head injury, suggesting that PTSD may develop in TBI survivors--even in those who cannot remember the traumatic event. Generally speaking, though, the overall balance of the findings (including our own findings) seems to support the possibility that, in subjects with TBI, impaired memory of the traumatic event is associated with reduced prevalence of PTSD.

CONCLUSIONS

The suggestion that amnesia regarding the traumatic event may protect against the development of PTSD has both theoretical and practical importance. This review focused on the case of traumatic brain injury as a model for impaired memory for the traumatic event. However, it still remains to be proven that the conclusions based on these findings are generalizable beyond the case of TBI. While some patients with posttraumatic amnesia do develop PTSD despite lack of memory for the traumatic event, the majority of those who lack memory for the event seem to be protected from developing the disorder. Nevertheless, based on this assumption, we suggest that pharmacologic disruption of newly acquired--or even old--traumatic memories, which has been shown to be possible in animals, might therapeutically benefit trauma survivors.

Early cognitive status and productivity outcome after traumatic brain injury: findings from the TBI model systems

OBJECTIVE

To evaluate the contribution of early cognitive assessment to the prediction of productivity outcome after traumatic brain injury (TBI) adjusted for severity of injury, demographic factors, and preinjury employment status.

DESIGN

Inception cohort.

SETTING

Six inpatient brain injury rehabilitation programs.

PARTICIPANTS

A total of 388 adults with TBI whose posttraumatic amnesia (PTA) resolved before discharge from inpatient rehabilitation.

INTERVENTIONS

Administered neuropsychologic tests during inpatient stay on emergence from PTA. Follow-up interview and evaluation. Predictor measures also determined.

MAIN OUTCOME MEASURE

Productivity status at follow-up 12 months postinjury.

RESULTS

Multiple logistic regression analysis revealed that preinjury productivity status, duration of PTA, education level, and early cognitive status each made significant, independent contributions to the prediction of productivity status at follow-up. When adjusted for all other predictors, persons scoring at the 75th percentile on early cognitive status (less impaired) had 1.61 times greater odds (95% confidence interval [CI], 1.07-2.41) of being productive follow-up than those scoring at the 25th percentile (more impaired). Without adjustment, persons scoring at the 75th percentile had 2.46 times greater odds (95% CI, 1.77-3.43) of being productive at follow-up.

CONCLUSIONS

Findings support the utility of early cognitive assessment by using neuropsychologic tests. In addition to other benefits, early cognitive assessment makes an independent contribution to prediction of late outcome. Findings support the clinical practice of performing initial neuropsychologic evaluations after resolution of PTA.

Predicting postconcussion syndrome after minor traumatic brain injury

BACKGROUND

Up to 50% of patients with minor traumatic brain injury (mTBI) develop postconcussion syndrome (PCS). A decision rule to stratify risk for PCS is needed.

OBJECTIVE

To identify mTBI patients at low and high risk of PCS by comparing the predictive values of variables generated by logistic regression (LR) and recursive partitioning (RP).

METHODS

This was a prospective, observational study of 69 mTBI patients aged >16 years presenting to the emergency department of a university teaching hospital. Minor TBI was defined as loss of consciousness <10 minutes or amnesia, Glasgow Coma Scale score (GCS) of 15, no skull fracture on physical examination, nonfocal neurologic exam, and no brain injury on computed tomography if one was done. Clinical/demographic data and the results of a brief neurobehavioral test battery were collected for all patients. The presence of PCS was determined by a validated telephone questionnaire at one month after initial presentation. All variables were subjected to both LR and RP.

RESULTS

Fifty-eight percent had PCS at one month after initial presentation. Low risk: PCS occurred in 9% of men scoring >24 on the Hopkins Verbal Learning A (HVLA) (by LR) and in 9% of those injured in sports scoring >22 on HVLA (RP). High risk: PCS occurred in 89% of women scoring <9 on the Digit Span test (LR) and in 92% of those injured via falls or motor vehicle collision scoring <11.5 on HVLB2 (RP).

CONCLUSIONS

Despite the high incidence of PCS, we were able to identify a low-risk subgroup with an average PCS risk of <10% and a high-risk subgroup with a PCS risk of approximately 90%. Combining results from LR and RP expanded the number of patients able to be classified as high/low risk. Prospective validation is necessary.

Using early neuropsychologic testing to predict long-term productivity outcome from traumatic brain injury

OBJECTIVE

To evaluate whether early neuropsychologic testing is useful in predicting long-term productivity outcome after traumatic brain injury (TBI).

DESIGN

Validation cohort prediction study.

SETTING

Four inpatient brain injury rehabilitation programs participating in the Traumatic Brain Injury Model Systems project.

PARTICIPANTS

A total of 293 adults with nonpenetrating TBI.

MAIN OUTCOME MEASURES

Fifteen neuropsychologic tests were administered to patients who emerged from posttraumatic amnesia before rehabilitation discharge. Test scores were classified in the normal range or impaired range, using objective criteria. Outcome was defined as productive if the patient was competitively employed or enrolled full time in regular education.

RESULTS

Productivity at follow-up was predicted by completion of at least 1 neuropsychologic test before discharge, by an injury-test interval of less than 2 months, and by normal range scores on 10 of the 15 neuropsychologic tests. Normal range scores on these tests increased the probability of a productive outcome by 40% to 130%.

CONCLUSIONS

Neuropsychologic testing can help predict long-term productivity even when performed before discharge from inpatient rehabilitation and at variable injury-test intervals. Early testing should be interpreted in relation to injury-test interval. Because tests of multiple neuropsychologic domains predicted outcome, comprehensive evaluations might be more useful in predicting outcome.

[What do patients with head injuries remember about their time of hospitalization?]

Traumatic brain injured (TBI) patients with different trauma severity were analyzed about their recollection concerning the period of hospitalization. The study was carried out in the Head Injury Outpatient Clinic at the Central Institute of the FMUSP Hospital including 45 conscious patients able to sustain an interview. Most patients were male, young adults with the major cause of trauma such as traffic accidents and falls. Most patients (86%) reported unconsciousness state of different time duration in their hospitalization period and were unable to remember anything related to that period. The predominant recollection reported by the patients who never had consciousness decreased after the trauma and that ones who had it but awoke during the hospitalization were: seeing, feeling, hearing, and reacting either to sounds and procedures.

A review of outcome after moderate and severe closed head injury with an introduction to life care planning

Forensic consultation regarding moderate and severe closed head injury (CHI) generally focuses on determination of severity of residual deficits and the implications of these deficits for future health care needs, personal independence, and employment. This information can be used to develop a life care plan that describes the patient's needs for continued medical care, rehabilitation, and daily assistance or supervision and estimates the long-term costs for these services. This article provides brief reviews of CHI classification, epidemiology, residual deficits, expected outcomes, and factors predictive of outcome. An introduction to the process of developing a life care plan is presented.

Cyclosporin ameliorates traumatic brain-injury-induced alterations of hippocampal synaptic plasticity

Although traumatic brain injury (TBI) often results in impaired learning and memory functions, the underlying mechanisms are unknown and there are currently no treatments that can preserve such functions. We studied plasticity at CA3-CA1 synapses in hippocampal slices from rats subjected to controlled cortical impact TBI. Long-term potentiation (LTP) of synaptic transmission was markedly impaired, whereas long-term depression (LTD) was enhanced, 48 h following TBI when compared to unoperated and sham control rats. Post-TBI administration of cyclosporin A, a compound that stabilizes mitochondrial function, resulted in a highly significant amelioration of the impairment of LTP and completely prevented the enhancement of LTD. Our data suggest that alterations in hippocampal synaptic plasticity may be responsible for learning and memory deficits resulting from TBI and that agents such as cyclosporin A that stabilize mitochondrial function may be effective treatments for TBI.

Prediction of community integration and vocational outcome 2-5 years after traumatic brain injury rehabilitation in Australia

OBJECTIVES

To predict community integration and vocational outcomes 2-5 years after traumatic brain injury (TBI).

DESIGN

Multivariate correlational design incorporating retrospective data collection and questionnaire follow-up.

METHODS

Four hundred and forty six patients admitted to a Head Injury Unit between 1991 and 1995 were contacted. Data on predictor variables (demographic, injury severity and functional) were retrieved from hospital records. Community integration and vocational outcome was assessed by self-administered questionnaire. Two hundred and nine patients/carers completed and returned the questionnaires. Mean follow-up was 3.5 years. Data were analysed by descriptive statistics, multiple regression and discriminant analysis using SPSS.

RESULTS

Community integration was predicted by age, disability level and cognition. Length of PTA, cognition, disability levels, GCS, functional status, length of acute stay and prior occupation discriminated those who returned to work. A total of 46.5% returned to work with 74.5% in the same or similar jobs.

CONCLUSION

Long term outcomes post-TBI can be predicted by demographic, injury severity and functional status variables.

One year outcome in mild to moderate head injury: the predictive value of acute injury characteristics related to complaints and return to work

OBJECTIVES

To determine the prognostic value of characteristics of acute injury and duration of post-traumatic amnesia (PTA) for long term outcome in patients with mild to moderate head injury in terms of complaints and return to work.

METHODS

Patients with a Glasgow coma score (GCS) on admission of 9-14 were included. Post-traumatic amnesia was assessed prospectively. Follow up was performed at 1, 3, 6, and 12 months after injury. Outcome was determined by the Glasgow outcome scale (GOS) 1 year after injury and compared with a more detailed outcome scale (DOS) comprising cognitive and neurobehavioural aspects.

RESULTS

Sixty seven patients were included, mean age 33.2 (SD 14.7) years and mean PTA 7.8 (SD 7.3) days. One year after injury, 73% of patients had resumed previous work although most (84%) still reported complaints. The most frequent complaints were headache (32%), irritability (34%), forgetfulness and poor concentration (42%), and fatigue (45%). According to the GOS good recovery (82%) or moderate disability (18%) was seen. Application of the DOS showed more cognitive (40%) and behavioural problems (48%), interfering with return to work. Correlation between the GOS and DOS was high (r=0.87, p<0.01). Outcome correlated with duration of PTA (r=-0.46) but not significantly with GCS on admission (r=0.19). In multiple regression analysis, PTA and the number of complaints 3 months after injury explained 49% of variance on outcome as assessed with the GOS, and 60% with the DOS.

CONCLUSIONS

In mild to moderate head injury outcome is determined by duration of PTA and not by GCS on admission. Most patients return to work despite having complaints. The application of a more detailed outcome scale will increase accuracy in predicting outcome in this category of patients with head injury.

Rehabilitation after traumatic brain injury in adults

PURPOSE

Traumatic brain injury (TBI) stands as a major public health problem and one of the most important challenges for neurological rehabilitation. This review discusses advances that have occurred in the past 10 years in rehabilitation after severe TBI in adults.

METHOD

First, theoretical concepts, goals of rehabilitation and organization of resources are reviewed. Then specific questions that arise in the rehabilitation of severe TBI patients are considered.

RESULTS

Three phases are distinguished in post-traumatic evolution. Acute rehabilitation takes place during coma and arousal states. Specific aims are to prevent orthopaedic and visceral complications, and to provide sensory stimulations with the hope of accelerating arousal. Secondly subacute (generally inpatient) rehabilitation is designed to facilitate and accelerate recovery of impairments, and to compensate for disabilities. Motility, cognition, behaviour, personality and affect should be simultaneously addressed in an holistic approach. Physical as well as psychological independence and self-awareness are the major goals to emphasize. A third, post-acute rehabilitation phase includes outpatient therapy for achieving physical, domestic and social independence, reduction of handicaps and re-entry into the community.

CONCLUSIONS

Problems with returning home, obtaining financial independence, driving, returning to work, participating in social relationships and leisure activities, and the importance of psychosocial adjustment and self-acceptance, are outlined. Questions about economic aspects and rehabilitation in the future are addressed.

Do calendars enhance posttraumatic temporal orientation?: a pilot study

The purpose of this study was to determine the effectiveness of an in-room calendar to correct temporal disorientation in a brain-injured population. Thirty consecutive brain injured patients (16 traumatic, 14 non-traumatic) admitted to a brain injury rehabilitation unit were randomly assigned to either a group with in-room calendars (n = 14) or a group without calendars (n = 16). A baseline Temporal Orientation Test (TOT) score was obtained. Daily TOT scores were obtained for patients throughout their rehabilitation stay or until two consecutive normal scores were obtained. When orientation errors were made, they were corrected and the attention of the patient was drawn to the calendar. There were no statistically significant associations between group and age, gender or mean GCS (for patients with traumatic etiology). Only baseline length of post-traumatic amnesia (PTA) had a significant association with eventual emergence from PTA (as defined by a normal score on the TOT). Age and presence of calendar were not significant. In-room calendars have been espoused as orientation aides. The data from this pilot study suggest that calendars do not hasten re-orientation. This finding suggests that other widely held but not rigorously tested beliefs regarding cognitive rehabilitation may need to be examined.

Posttraumatic amnesia: its relation to functional outcome

OBJECTIVE

To investigate the relation between duration of posttraumatic amnesia (PTA) and functional outcome in a traumatically brain injured population.

PATIENTS

Two hundred seventy-six patients with traumatic brain injury (TBI) who were admitted to a Level I university trauma center and required inpatient rehabilitation.

MEASURES

Duration of PTA was assessed by serial administrations of the Galveston Orientation Amnesia Test (GOAT). Functional Independence Measure (FIM) total scores, FIM cognitive and motor subscores, and Disability Rating Scale (DRS) scores were obtained at admission and discharge from inpatient rehabilitation.

RESULTS

Duration of PTA was a significant predictor of all admission and discharge DRS and FIM scores. Duration of PTA and age at the time of injury, in combination, contributed significantly to the prediction of the DRS score and FIM total, cognitive, and motor scores at discharge.

CONCLUSION

Duration of PTA appears to be a useful variable in predicting specific functional outcome in the TBI population receiving inpatient rehabilitation services. The use of age as a factor in addition to duration of PTA enhances the prediction of functional outcome.