Monitoring prognosis in severe traumatic brain injury

The choice of disease-specific versus generic scales is common to many fields of medicine. In the area of traumatic brain injury, evidence is coming forward that disease-specific prognostic models and disease-specific scoring systems are preferable in the intensive care setting. In monitoring prognosis, the use of a calibration belt in validation studies potentially provides accurate and intuitively attractive insight into performance. This approach deserves further empirical evaluation of its added value as well as its limitations

Cerebrospinal fluid enzymes in acute brain injury

Severe brain injury is a major cause of death, especially in young men. In 1972, over 20% of all deaths occurring in England and Wales in men aged 15-25 years were due to head injury (Field, 1976). The mortality rate after severe brain injuries is higb. Jennett et al. (1977) reporting on a large international study comprising 700 patients describe a 53% mortality rate. In this study patients with brain injuries were studied in whom consciousness was suppressed for a period of at least six hours to a degree that inability to obey commands, to speak, or to open the eyes existed. Studies reported from different parts of Europe show a similar mortality rate (table 1 ). Not only do severe brain injuries call a large death toll, but many of the patients who survive remain disabled, often for life. Of 65 patients who were admitted to the University Hospital of Rotterdam in the period 1974-1976 with severe brain injury and were still alive after 6 months, 24 (37%) were disabled at that time. Disability may be due to physical sequelae, to disturbances of mental function, which are especially common following head injuries, or to difficulties arising when social reintegration is attempted

Tranexamic acid in traumatic brain injury: systematic review and meta-analysis trumps a large clinical trial?

Development and application of statistical models for medical scientific researchAnalysis and support of clinical decision makin

Differential effects of the Glasgow Coma Scale Score and its Components: An analysis of 54,069 patients with traumatic brain injury

INTRODUCTION: The Glasgow Coma Scale (GCS) is widely used in the assessment of clinical severity and prediction of outcome after traumatic brain injury (TBI). The sum score is frequently applied, but the differential influence of the components infrequently addressed. We aimed to investigate the contribution of the GCS components to the sum score, floor and ceiling effects of the components, and their prognostic effects. METHODS: Data on adult TBI patients were gathered from three data repositories: TARN (n=50,064), VSTR (n=14,062), and CRASH (n=9,941). Data on initial hospital GCS-assessment and discharge mortality were extracted. A descriptive analysis was performed to identify floor and ceiling effects. The relation between GCS and outcome was studied by comparing case fatality rates (CFR) between different component-profiles adding up to identical sum scores using Chi(2)-tests, and by quantifying the prognostic value of each component and sum score with Nagelkerke's R(2) derived from logistic regression analyses across TBI severities. RESULTS: In the range 3-7, the sum score is primarily determined by the motor component, as the verbal and eye components show floor-effects at sum scores 7 and 8, respectively. In the range 8-12, the effect of the motor component attenuates and the verbal and eye components become more relevant. The motor, eye and verbal scores reach their ceiling-effects at sum 13, 14 and 15, respectively. Significant variations were exposed in CFR between different component-profiles despite identical sum scores, except in sum scores 6 and 7. Regression analysis showed that the motor score had highest R(2) values in severe TBI patients, whereas the other components were more relevant at higher sum scores. The prognostic value of the three components combined was consistently higher than that of the sum score alone. CONCLUSION: The GCS-components contribute differentially across the spectrum of consciousness to the sum score, each having floor and ceiling effects. The specific component-profile is related to outcome and the three components combined contain higher prognostic value than the sum score across different TBI severities. We, therefore, recommend a multidimensional use of the three-component GCS both in clinical practice, and in prognostic studies

Epidemiology of traumatic brain injury in Europe

Background: Traumatic brain injury (TBI) is a critical public health and socio-economic problem throughout the world, making epidemiological monitoring of incidence, prevalence and outcome of TBI necessary. We aimed to describe the epidemiology of traumatic brain injury in Europe and to evaluate the methodology of incidence studies. Method: We performed a systematic review and meta-analyses of articles describing the epidemiology of TBI in European countries. A search was conducted in the PubMed electronic database using the terms: epidemiology, incidence, brain injur*, head injur* and Europe. Only articles published in English and reporting on data collected in Europe between 1990 and 2014 were included. Results: In total, 28 epidemiological studies on TBI from 16 European countries were identified in the literature. A great variation was found in case definitions and case ascertainment between studies. Falls and road traffic accidents (RTA) were the two most frequent causes of TBI, with falls being reported more frequently than RTA. In most of the studies a peak TBI incidence was seen in the oldest age groups. In the meta-analysis, an overall incidence rate of 262 per 100,000 for admitted TBI was derived. Conclusions: Interpretation of published epidemiologic studies is confounded by differences in inclusion criteria and case ascertainment. Nevertheless, changes in epidemiological patterns are found: falls are now the most common cause of TBI, most notably in elderly patients. Improvement of the quality of standardised data collection for TBI is mandatory for reliable monitoring of epidemiological trends and to inform appropriate targeting of prevention campaigns

Common Data Elements: Critical Assessment of Harmonization between Current Multi-Center Traumatic Brain Injury Studies

Standardization and harmonization of data collection in studies on traumatic brain injury (TBI) is of paramount importance for meta-analyses across studies. Nearly 10 years ago, the first set of Common Data Elements for TBI (TBI-CDEs v1) were introduced to achieve these goals. The TBI-CDEs version 2 wer

Variation in the practice of tracheal intubation in Europe after traumatic brain injury: a prospective cohort study

Traumatic brain injury patients frequently undergo tracheal intubation. We aimed to assess current intubation practice in Europe and identify variation in practice. We analysed data from patients with traumatic brain injury included in the prospective cohort study collaborative European neurotrauma effectiveness research in traumatic brain injury (CENTER-TBI) in 45 centres in 16 European countries. We included patients who were transported to hospital by emergency medical services. We used mixed-effects multinomial regression to quantify the effects on pre-hospital or in-hospital tracheal intubation of the following: patient characteristics; injury characteristics; centre; and trauma system characteristics. A total of 3843 patients were included. Of these, 1322 (34%) had their tracheas intubated; 839 (22%) pre-hospital and 483 (13%) in-hospital. The fit of the model with only patient characteristics predicting intubation was good (Nagelkerke R2 64%). The probability of tracheal intubation increased with the following: younger age; lower pre-hospital or emergency department GCS; higher abbreviated injury scale scores (head and neck, thorax and chest, face or abdomen abbreviated injury score); and one or more unreactive pupils. The adjusted median odds ratio for intubation between two randomly chosen centres was 3.1 (95%CI 2.1-4.3) for pre-hospital intubation, and 2.7 (95%CI 1.9-3.5) for in-hospital intubation. Furthermore, the presence of an anaesthetist was independently associated with more pre-hospital intubation (OR 2.9, 95%CI 1.3-6.6), in contrast to the presence of ambulance personnel who are allowed to intubate (OR 0.5, 95%CI 0.3-0.8). In conclusion, patient and injury characteristics are key drivers of tracheal intubation. Between-centre differences were also substantial. Further studies are needed to improve the evidence base supporting recommendations for tracheal intubation

Imputation of ordinal outcomes: a comparison of approaches in Traumatic Brain Injury

Loss to follow-up and missing outcomes data are important issues for longitudinal observational studies and clinical trials in traumatic brain injury. One popular solution to missing 6-month outcomes has been to use the last observation carried forward (LOCF). The purpose of the current study was to compare the performance of model-based single-imputation methods with that of the LOCF approach. We hypothesized that model-based methods would perform better as they potentially make better use of available outcome data. The Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study (n = 4509) included longitudinal outcome collection at 2 weeks, 3 months, 6 months, and 12 months post-injury; a total of 8185 Glasgow Outcome Scale extended (GOSe) observations were included in the database. We compared single imputation of 6-month outcomes using LOCF, a multiple imputation (MI) panel imputation, a mixed-effect model, a Gaussian process regression, and a multi-state model. Model performance was assessed via cross-validation on the subset of individuals with a valid GOSe value within 180 +/- 14 days post-injury (n = 1083). All models were fit on the entire available data after removing the 180 +/- 14 days post-injury observations from the respective test fold. The LOCF method showed lower accuracy (i.e., poorer agreement between imputed and observed values) than model-based methods of imputation, and showed a strong negative bias (i.e., it imputed lower than observed outcomes). Accuracy and bias for the model-based approaches were similar to one another, with the multi-state model having the best overall performance. All methods of imputation showed variation across different outcome categories, with better performance for more frequent outcomes. We conclude that model-based methods of single imputation have substantial performance advantages over LOCF, in addition to providing more complete outcome data.Development and application of statistical models for medical scientific researc

Prehospital Trauma Care among 68 European Neurotrauma Centers: Results of the CENTER-TBI Provider Profiling Questionnaires

The first hour following traumatic brain injury (TBI) is considered crucial to prevent death and disability. It is, however, not established yet how the prehospital care should be organized to optimize recovery during the first hour. The objective of the current study was to examine variation in prehospital trauma care across Europe aiming to inform comparative effectiveness analyses on care for neurotrauma patients. A survey on prehospital trauma care was sent to 68 neurotrauma centers from 20 European countries participating in the Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI) study. The survey was developed using literature review and expert opinion and was pilot tested in 16 centers. All participants completed the questionnaire. Advanced life support was used in half of the centers (n = 35; 52%), whereas the other centers used mainly basic life support (n = 26; 38%). A mobile medical team (MMT) could be dispatched 24/7 in most centers (n = 66; 97%). Helicopters were used in approximately half of the centers to transport the MMT to the scene (n = 39; 57%) and the patient to the hospital (n = 31, 46%). Half of the centers used a stay-and-play approach at the scene (n = 37; 55%), while the others used a scoop-and-run approach or another policy. We found wide variation in prehospital trauma care across Europe. This may reflect differences in socio-economic situations, geographic differences, and a general lack of strong evidence for some aspects of prehospital care. The current variation provides the opportunity to study the effectiveness of prehospital interventions and systems of care in comparative effectiveness research