Diagnostic accuracy of clinical characteristics for identifying CT abnormality after minor brain injury: a systematic review and meta-analysis

Traumatic Brain Injury in Patients under Anticoagulant Therapy: Review of Management in Emergency Department

The best management of patients who suffer from traumatic brain injury (TBI) while on oral anticoagulants is one of the most disputed problems of emergency services. Indeed, guidelines, clinical decision rules, and observational studies addressing this topic are scarce and conflicting. Moreover, relevant issues such as the specific treatment (and even definition) of mild TBI, rate of delayed intracranial injury, indications for neurosurgery, and anticoagulant modulation are largely empiric. We reviewed the most recent evidence on these topics and explored other clinically relevant aspects, such as the promising role of dosing brain biomarkers, the strategies to assess the extent of anticoagulation, and the indications of reversals and tranexamic acid administration, in cases of mild TBI or as a bridge to neurosurgery. The appropriate timing of anticoagulant resumption was also discussed. Finally, we obtained an insight into the economic burden of TBI in patients on oral anticoagulants, and future directions on the management of this subpopulation of TBI patients were proposed. In this article, at the end of each section, a "take home message" is stated.

Effects of the COVID-19 Pandemic on Treatment Efficiency for Traumatic Brain Injury in the Emergency Department: A Multicenter Study in Taiwan

The coronavirus disease 2019 (COVID-19) pandemic has impacted emergency department (ED) practice, including the treatment of traumatic brain injury (TBI), which is commonly encountered in the ED. Our study aimed to evaluate TBI treatment efficiency in the ED during the COVID-19 pandemic. A retrospective observational study was conducted using the electronic medical records from three hospitals in metropolitan Taipei, Taiwan. The time from ED arrival to brain computed tomography (CT) and the time from ED arrival to surgical management were used as measures of treatment efficiency. TBI treatment efficiencies in the ED coinciding with a small-scale local COVID-19 outbreak in 2020 (P1) and large-scale community spread in 2021 (P2) were compared against the pre-pandemic efficiency recorded in 2019. The interval between ED arrival and brain CT was significantly shortened during P1 and P2 compared with the pre-pandemic interval, and no significant delay between ED arrival and surgical management was found, indicating increased treatment efficiency for TBI in the ED during the COVID-19 pandemic. Minimizing viral spread in the community and the hospital is vital to maintaining ED treatment efficiency and capacity. The ED should retain sufficient capacity to treat older patients with serious TBI during the COVID-19 pandemic.

Accuracy of PECARN decision rule in minor blunt head trauma in pediatric emergency department: A meta-analysis

BACKGROUND

Paediatric Emergency Care Applied Research Network (PECARN) is a useful Clinical Decision Support Tool (CDST) to identify traumatic brain injuries and reduce the use of head computed tomography (CT) scans among paediatric patients. The present Meta-analysis aims to evaluate the diagnostic accuracy of the PECARN rule from 2009 to 2020 in children with a very low risk of blunt head trauma.

METHODS

A detailed search was conducted from the databases of Medline (via PubMed), Cinahl (via Ebsco), Scopus, Web of Sciences, from 2009 till the end of December 2020 using the keywords like decreased use of CT scan, blunt head trauma (BHT) combined with accuracy, PECARN OR CDST. Studies showing the diagnostic accuracy of the PECARN rule in children younger than 18 years of age with minor BHT were included.

RESULTS

Thirteen studies were included in the present analysis. Pooled sensitivity of 0.08, (95% confidence interval of 0.074-0.087), pooled specificity of 0.20 (95% CI of 0.196-0.213) and diagnostic odds ratio of 0.004 (95% CI of 0.000-0.1666) was in <2 years of age. The overall sensitivity of 0.07, specificity of 0.66, and the diagnostic odds ratio of 0.54 (95% CI of 0.10-2.78) were seen in ≥2 years of age. Overall sensitivity of 0.13 (95% CI 0.12-0.14), specificity of 0.81 (95% CI 0.80-0.82) and diagnostic odds ratio of 0.79 (95% CI of 0.08-7.71) was in 0-18 years of age.

CONCLUSION

The present analysis indicates the PECARN decision tool as an accurate CDST in low-risk minor BHT cases in children below two years of age and can become a valuable tool in reducing Head CT scan overuse in paediatric emergency departments.

Biofluid Biomarkers in Traumatic Brain Injury: A Systematic Scoping Review

Emerging evidence suggests that biofluid-based biomarkers have diagnostic and prognostic potential in traumatic brain injuries (TBI). However, owing to the lack of a conceptual framework or comprehensive review, it is difficult to visualize the breadth of materials that might be available. We conducted a systematic scoping review to map and categorize the evidence regarding biofluid-based biochemical markers of TBI. A comprehensive search was undertaken in January 2019. Of 25,354 records identified through the literature search, 1036 original human studies were included. Five hundred forty biofluid biomarkers were extracted from included studies and classified into 19 distinct categories. Three categories of biomarkers including cytokines, coagulation tests, and nerve tissue proteins were investigated more than others and assessed in almost half of the studies (560, 515, and 502 from 1036 studies, respectively). S100 beta as the most common biomarker for TBI was tested in 21.2% of studies (220 articles). Cortisol was the only biomarker measured in blood, cerebrospinal fluid, urine, and saliva. The most common sampling time was at admission and within 24 h of injury. The included studies focused mainly on biomarkers from blood and central nervous system sources, the adult population, and severe and blunt injuries. The most common outcome measures used in studies were changes in biomarker concentration level, Glasgow coma scale, Glasgow outcome scale, brain computed tomography scan, and mortality rate. Biofluid biomarkers could be clinically helpful in the diagnosis and prognosis of TBI. However, there was no single definitive biomarker with accurate characteristics. The present categorization would be a road map to investigate the biomarkers of the brain injury cascade separately and detect the most representative biomarker of each category. Also, this comprehensive categorization could provide a guiding framework to design combined panels of multiple biomarkers.

Traumatic Brain Injury in Patients Receiving Direct Oral Anticoagulants

BACKGROUND

Emergency departments (EDs) are faced with a growing number of patients with traumatic brain injury (TBI) using direct oral anticoagulants (DOACs). However, there remains uncertainty about the bleeding risk, rate of hematoma expansion, and the efficacy of reversal strategies in these patients.

OBJECTIVE

This study aims to identify the risk of traumatic hemorrhagic complications in patients with TBI using DOACs.

METHODS

In this retrospective study we included patients with TBI. All TBI patients were using DOACs, attended one of the three EDs of our hospital between January 2016 and October 2019, and received a computed tomography (CT) scan of the brain. The primary outcome was any traumatic intracranial hemorrhage on CT. Secondary outcomes were the use of reversal agents, secondary neurological deterioration, a neurosurgical intervention within 30 days after the injury, length of stay (LOS), Glasgow Outcome Scale (GOS) at discharge, and mortality.

RESULTS

Of the included patients (N = 316), 24 patients (7.6%, 95% confidence interval [CI] 4.2-9.8) presented with a traumatic intracranial hematoma (ICH). Seven patients (2.2%, 95% CI 0.6-3.8) received a reversal agent and 1 patient (0.3%, 95% CI -0.3-0.9) underwent a neurosurgical intervention. Of the 24 patients with a traumatic ICH, progression of the lesion was seen in 6 patients (1.9%, 95% CI 0.4-3.4). The mean LOS was 6.5 days (95% CI 3.0-10.1) and the mean GOS at discharge was 4 (95% CI 3.6-4.6). Death occurred in 1 patient (0.3%, 95% CI -0.3-0.9) suffering from an ICH.

CONCLUSION

Based on the present findings it can be postulated that TBI patients using DOACs have a low risk for ICH. Hematoma progression occurred, however, in a substantial number of patients. Considering the retrospective nature of the present study, future prospective trials are needed to confirm this finding.

Traumatic Brain Injury during the SARS-CoV-2 Pandemic

Emergency departments (EDs) are eerily quiet for illnesses apart from COVID-19. In this short communication, we assessed the effect of COVID-19 on ED attendance rates for traumatic brain injury (TBI). Data were collected from all consecutive patients with TBI attending our hospital (Haaglanden Medical Center, The Hague, The Netherlands) during the first 3 weeks of the Dutch lockdown (from March 18 to April 6) and for the same period last year. We observed a 36% decrease in ED attendance for TBI since the beginning of the SARS-CoV-2 pandemic (91 vs. 143). Patients who presented during the lockdown were significantly older compared with the patients who visited the ED in the previous year (72 vs. 57, p = 0.01). No other significant differences were found.

Systematic review and meta-analysis found significant risk of brain injury and neurosurgery in alert children after a post-traumatic seizure

AIM

This study aimed to determine the frequency of traumatic brain injury (TBI) on neuroimaging and the need for emergency neurosurgery in children with normal mental status following a post-traumatic seizure (PTS).

METHODS

We searched six electronic databases from inception to October 15, 2018, to identify studies including children under 18 years with head injury and a Glasgow Coma Score of 15 after an immediate PTS. Relevant non-English articles were translated to determine eligibility.

RESULTS

We performed random effect meta-analyses and assessed heterogeneity with I² . The pooled estimate of the frequency of TBI, from seven studies, was 13.0% (95% CI: 4.0-26.1; I²  = 81%). Data on the need of emergency neurosurgery were reported in four studies and the pooled estimate of its frequency was 2.3% (95% CI: 0.0-9.9; I²  = 86%). Two studies reported on children with isolated PTS without any other signs of head injury, representing 0.1% of patients in both studies, for a total of 76 children. Of these, only three had TBI and one underwent neurosurgery.

CONCLUSION

Children with immediate PTS and normal mental status frequently have TBI with a substantial need for neurosurgery. Clinicians should strongly consider neuroimaging for these children, although prolonged observation may be considered for those with isolated PTS.

Grading and assessment of clinical predictive tools for paediatric head injury: a new evidence-based approach

BACKGROUND

Many clinical predictive tools have been developed to diagnose traumatic brain injury among children and guide the use of computed tomography in the emergency department. It is not always feasible to compare tools due to the diversity of their development methodologies, clinical variables, target populations, and predictive performances. The objectives of this study are to grade and assess paediatric head injury predictive tools, using a new evidence-based approach, and to provide emergency clinicians with standardised objective information on predictive tools to support their search for and selection of effective tools.

METHODS

Paediatric head injury predictive tools were identified through a focused review of literature. Based on the critical appraisal of published evidence about predictive performance, usability, potential effect, and post-implementation impact, tools were evaluated using a new framework for grading and assessment of predictive tools (GRASP). A comprehensive analysis was conducted to explain why certain tools were more successful.

RESULTS

Fourteen tools were identified and evaluated. The highest-grade tool is PECARN; the only tool evaluated in post-implementation impact studies. PECARN and CHALICE were evaluated for their potential effect on healthcare, while the remaining 12 tools were only evaluated for predictive performance. Three tools; CATCH, NEXUS II, and Palchak, were externally validated. Three tools; Haydel, Atabaki, and Buchanich, were only internally validated. The remaining six tools; Da Dalt, Greenes, Klemetti, Quayle, Dietrich, and Güzel did not show sufficient internal validity for use in clinical practice.

CONCLUSIONS

The GRASP framework provides clinicians with a high-level, evidence-based, comprehensive, yet simple and feasible approach to grade, compare, and select effective predictive tools. Comparing the three main tools which were assigned the highest grades; PECARN, CHALICE and CATCH, to the remaining 11, we find that the quality of tools' development studies, the experience and credibility of their authors, and the support by well-funded research programs were correlated with the tools' evidence-based assigned grades, and were more influential, than the sole high predictive performance, on the wide acceptance and successful implementation of the tools. Tools' simplicity and feasibility, in terms of resources needed, technical requirements, and training, are also crucial factors for their success.

[Quality standards in treatment and rehabilitation of traumatic brain injuries]

The quality standards of the "Deutsche gesetzliche Unfallversicherung" (DGUV) on the treatment of traumatic brain injuries were first published in 2015. They describe the optimal conditions and requirements of acute treatment and in all phases of rehabilitation and aftercare, according to the current state of knowledge. The aim is to enable a life worth living in family, school, occupation and society for as many injuries as possible. The quality standards, as systematic orientation and decision-making aids, should promote the future development of the treatment and rehabilitation of traumatic brain injuries of all grades of severity and guarantee a uniformly high quality of treatment. A special and comprehensive rehabilitative alignment as well as a close networking of medical and occupation-promoting services will be of particular importance for the institutions participating in the rehabilitation of patients with traumatic brain injuries.

Experimental Designs for Repeated Mild Traumatic Brain Injury: Challenges and Considerations

Mild traumatic brain injury (mild TBI) is a growing public concern, as evidence mounts that even brain injuries classified as "mild" can result in persistent neurological dysfunction. Multiple brain injuries heighten the likelihood of worsened or more prolonged symptomatology and may trigger long-term neurodegeneration. Animal models provide a logical platform to identify key parameters, such as loading forces, duration between injuries, and number of injuries, which contribute to additive or synergistic damage after repeated mild TBI. Despite the tremendous increase in research productivity in the field of repeated mild TBI, relatively few studies have been designed in such a way as to provide experimental-based insights into the dependence of cellular and functional outcomes on the prescribed parameters of mild TBI. In this review, we summarize how standard models of TBI have been adapted to produce mild TBI and highlight commonly observed aspects of neuropathology replicated in rodent models of mild TBI. The complexity of designing studies of repeated TBI is discussed, including challenges of incorporating appropriate control groups, informative experimental design, and relevant outcome measures. We then feature studies that provide a well-controlled, within-study design varying either the number of injuries or the interinjury interval. Harnessing the power of experimental models of TBI to elucidate which injury parameters are critical contributors to acute and chronic damage after repeated injury can further efforts at prevention and provide improved models for testing mechanisms and therapeutic interventions.

Economic evaluation of the NET intervention versus guideline dissemination for management of mild head injury in hospital emergency departments

BACKGROUND

Evidence-based guidelines for the management of mild traumatic brain injury (mTBI) in the emergency department (ED) are now widely available, and yet, clinical practice remains inconsistent with the guidelines. The Neurotrauma Evidence Translation (NET) intervention was developed to increase the uptake of guideline recommendations and improve the management of minor head injury in Australian emergency departments (EDs). However, the adoption of this type of intervention typically entails an upfront investment that may or may not be fully offset by improvements in clinical practice, health outcomes and/or reductions in health service utilisation. The present study estimates the cost and cost-effectiveness of the NET intervention, as compared to the passive dissemination of the guideline, to evaluate whether any improvements in clinical practice or health outcomes due to the NET intervention can be obtained at an acceptable cost.

METHODS AND FINDINGS

Study setting: The NET cluster randomised controlled trial [ACTRN12612001286831].

STUDY SAMPLE

Seventeen EDs were randomised to the control condition and 14 to the intervention. One thousand nine hundred forty-three patients were included in the analysis of clinical practice outcomes (NET sample). A total of 343 patients from 14 control and 10 intervention EDs participated in follow-up interviews and were included in the analysis of patient-reported health outcomes (NET-Plus sample).

OUTCOME MEASURES

Appropriate post-traumatic amnesia (PTA) screening in the ED (primary outcome). Secondary clinical practice outcomes: provision of written information on discharge (INFO) and safe discharge (defined as CT scan appropriately provided plus PTA plus INFO). Secondary patient-reported, post-discharge health outcomes: anxiety (Hospital Anxiety and Depression Scale), post-concussive symptoms (Rivermead), and preference-based health-related quality of life (SF6D).

METHODS

Trial-based economic evaluations from a health sector perspective, with time horizons set to coincide with the final follow-up for the NET sample (2 months post-intervention) and to 1-month post-discharge for the NET-Plus sample.

RESULTS

Intervention and control groups were not significantly different in health service utilisation received in the ED/inpatient ward following the initial mTBI presentation (adjusted mean difference $23.86 per patient; 95%CI - $106, $153; p = 0.719) or over the longer follow-up in the NET-plus sample (adjusted mean difference $341.78 per patient; 95%CI - $58, $742; p = 0.094). Savings from lower health service utilisation are therefore unlikely to offset the significantly higher upfront cost of the intervention (mean difference $138.20 per patient; 95%CI $135, $141; p < 0.000). Estimates of the net effect of the intervention on total cost (intervention cost net of health service utilisation) suggest that the intervention entails significantly higher costs than the control condition (adjusted mean difference $169.89 per patient; 95%CI $43, $297, p = 0.009). This effect is larger in absolute magnitude over the longer follow-up in the NET-plus sample (adjusted mean difference $505.06; 95%CI $96, $915; p = 0.016), mostly due to additional health service utilisation. For the primary outcome, the NET intervention is more costly and more effective than passive dissemination; entailing an additional cost of $1246 per additional patient appropriately screened for PTA ($169.89/0.1363; Fieller's 95%CI $525, $2055). For NET to be considered cost-effective with 95% confidence, decision-makers would need to be willing to trade one quality-adjusted life year (QALY) for 25 additional patients appropriately screened for PTA. While these results reflect our best estimate of cost-effectiveness given the data, it is possible that a NET intervention that has been scaled and streamlined ready for wider roll-out may be more or less cost-effective than the NET intervention as delivered in the trial.

CONCLUSIONS

While the NET intervention does improve the management of mTBI in the ED, it also entails a significant increase in cost and-as delivered in the trial-is unlikely to be cost-effective at currently accepted funding thresholds. There may be a scope for a scaled-up and streamlined NET intervention to achieve a better balance between costs and outcomes.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12612001286831 , date registered 12 December 2012.

Characterizing the type and location of intracranial abnormalities in mild traumatic brain injury

OBJECTIVEThe incidence of intracranial abnormalities after mild traumatic brain injury (TBI) varies widely across studies. This study describes the characteristics of intracranial abnormalities (acute/preexisting) in a large representative sample of head-injured patients who underwent CT imaging in an emergency department.METHODSCT scans were systematically analyzed/coded in the TBI Common Data Elements framework. Logistic regression modeling was used to quantify risk factors for traumatic intracranial abnormalities in patients with mild TBIs. This cohort included all patients who were treated at the emergency department of the Tampere University Hospital (between 2010 and 2012) and who had undergone head CT imaging after suffering a suspected TBI (n = 3023), including 2766 with mild TBI and a reference group with moderate to severe TBI.RESULTSThe most common traumatic lesions seen on CT scans obtained in patients with mild TBIs and those with moderate to severe TBIs were subdural hematomas, subarachnoid hemorrhages, and contusions. Every sixth patient (16.1%) with mild TBI had an intracranial lesion compared with 5 of 6 patients (85.6%) in the group with moderate to severe TBI. The distribution of different types of acute traumatic lesions was similar among mild and moderate/severe TBI groups. Preexisting brain lesions were a more common CT finding among patients with mild TBIs than those with moderate to severe TBIs. Having a past traumatic lesion was associated with increased risk for an acute traumatic lesion but neurodegenerative and ischemic lesions were not. A lower Glasgow Coma Scale score, male sex, older age, falls, and chronic alcohol abuse were associated with higher risk of acute intracranial lesion in patients with mild TBI.CONCLUSIONSThese findings underscore the heterogeneity of neuropathology associated with the mild TBI classification. Preexisting brain lesions are common in patients with mild TBI, and the incidence of preexisting lesions increases with age. Acute traumatic lesions are fairly common in patients with mild TBI; every sixth patient had a positive CT scan. Older adults (especially men) who fall represent a susceptible group for acute CT-positive TBI.

Incidence, course and risk factors of head injury: a retrospective cohort study

OBJECTIVES

To assess the incidence of head injury and predictors of complication across the care continuum.

DESIGN

Retrospective cohort study using data from a research network. We calculated the incidence of overall head injury in a longitudinal cohort covering 1-year interval (31 369 patient-years), and the incidence of complicated head injury in a longitudinal cohort covering 10 years interval (220 352 patient-ears). Incidence rates were calculated per 1000 patient-years with 95% CI using the Mid-P exact test. We calculated ORs to assess potential risk factors for a complicated head injury.

SETTING

A practice-based research network covering a population of >30 000 patients.

PARTICIPANTS

All patients listed in practices within the research network during the years 2005-2014.

MAIN OUTCOME MEASURES

Incidence of (complicated) head injury and predictors for clinical complications.

RESULTS

The incidence of overall head injury was 22.1 per 1000 person-years and the incidence of a complicated course following head injury was 0.16 per 1000 person-years. The following determinants were risk factors for a complicated course: high energy trauma, bicycle accident, traffic accident in general, use of anticoagulants, alcohol intoxication, age above 60 years and low Glasgow Coma Scale at initial presentation. A complicated course was very unlikely when the patients' first encounter with a healthcare professional was in primary care (OR 0.03, 95% CI 0.01 to 0.07).

CONCLUSIONS

Complication after head injury are rarely seen in general practice. Patients who do experience complications are often easily identifiable as requiring specialist care. A more reserved referral policy for general practice may be desirable, suggesting that current guidelines are too defensive.

Vomiting With Head Trauma and Risk of Traumatic Brain Injury

OBJECTIVES

To determine the prevalence of traumatic brain injuries in children who vomit after head injury and identify variables from published clinical decision rules (CDRs) that predict increased risk.

METHODS

Secondary analysis of the Australasian Paediatric Head Injury Rule Study. Vomiting characteristics were assessed and correlated with CDR predictors and the presence of clinically important traumatic brain injury (ciTBI) or traumatic brain injury on computed tomography (TBI-CT). Isolated vomiting was defined as vomiting without other CDR predictors.

RESULTS

Of the 19 920 children enrolled, 3389 (17.0%) had any vomiting, with 2446 (72.2%) >2 years of age. In 172 patients with ciTBI, 76 had vomiting (44.2%; 95% confidence interval [CI] 36.9%-51.7%), and in 285 with TBI-CT, 123 had vomiting (43.2%; 95% CI 37.5%-49.0%). With isolated vomiting, only 1 (0.3%; 95% CI 0.0%-0.9%) had ciTBI and 2 (0.6%; 95% CI 0.0%-1.4%) had TBI-CT. Predictors of increased risk of ciTBI with vomiting by using multivariate regression were as follows: signs of skull fracture (odds ratio [OR] 80.1; 95% CI 43.4-148.0), altered mental status (OR 2.4; 95% CI 1.0-5.5), headache (OR 2.3; 95% CI 1.3-4.1), and acting abnormally (OR 1.86; 95% CI 1.0-3.4). Additional features predicting TBI-CT were as follows: skull fracture (OR 112.96; 95% CI 66.76-191.14), nonaccidental injury concern (OR 6.75; 95% CI 1.54-29.69), headache (OR 2.55; 95% CI 1.52-4.27), and acting abnormally (OR 1.83; 95% CI 1.10-3.06).

CONCLUSIONS

TBI-CT and ciTBI are uncommon in children presenting with head injury with isolated vomiting, and a management strategy of observation without immediate computed tomography appears appropriate.

Neuropsychological outcome and diffusion tensor imaging in complicated versus uncomplicated mild traumatic brain injury

This study examined whether intracranial neuroimaging abnormalities in those with mild traumatic brain injury (MTBI) (i.e., “complicated” MTBIs) are associated with worse subacute outcomes as measured by cognitive testing, symptom ratings, and/or diffusion tensor imaging (DTI). We hypothesized that (i) as a group, participants with complicated MTBIs would report greater symptoms and have worse neurocognitive outcomes than those with uncomplicated MTBI, and (ii) as a group, participants with complicated MTBIs would show more Diffusion Tensor Imaging (DTI) abnormalities. Participants were 62 adults with MTBIs (31 complicated and 31 uncomplicated) who completed neurocognitive testing, symptom ratings, and DTI on a 3T MRI scanner approximately 6-8 weeks post injury. There were no statistically significant differences between groups on symptom ratings or on a broad range of neuropsychological tests. When comparing the groups using tract-based spatial statistics for DTI, no significant difference was found for axial diffusivity or mean diffusivity. However, several brain regions demonstrated increased radial diffusivity (purported to measure myelin integrity), and decreased fractional anisotropy in the complicated group compared with the uncomplicated group. Finally, when we extended the DTI analysis, using a multivariate atlas based approach, to 32 orthopedic trauma controls (TC), the findings did not reveal significantly more areas of abnormal DTI signal in the complicated vs. uncomplicated groups, although both MTBI groups had a greater number of areas with increased radial diffusivity compared with the trauma controls. This study illustrates that macrostructural neuroimaging changes following MTBI are associated with measurable changes in DTI signal. Of note, however, the division of MTBI into complicated and uncomplicated subtypes did not predict worse clinical outcome at 6-8 weeks post injury.

Implementing evidence-based recommended practices for the management of patients with mild traumatic brain injuries in Australian emergency care departments: study protocol for a cluster randomised controlled trial

Background

Mild head injuries commonly present to emergency departments. The challenges facing clinicians in emergency departments include identifying which patients have traumatic brain injury, and which patients can safely be sent home. Traumatic brain injuries may exist with subtle symptoms or signs, but can still lead to adverse outcomes. Despite the existence of several high quality clinical practice guidelines, internationally and in Australia, research shows inconsistent implementation of these recommendations. The aim of this trial is to test the effectiveness of a targeted, theory- and evidence-informed implementation intervention to increase the uptake of three key clinical recommendations regarding the emergency department management of adult patients (18 years of age or older) who present following mild head injuries (concussion), compared with passive dissemination of these recommendations. The primary objective is to establish whether the intervention is effective in increasing the percentage of patients for which appropriate post-traumatic amnesia screening is performed.

Methods/design

The design of this study is a cluster randomised trial. We aim to include 34 Australian 24-hour emergency departments, which will be randomised to an intervention or control group. Control group departments will receive a copy of the most recent Australian evidence-based clinical practice guideline on the acute management of patients with mild head injuries. The intervention group will receive an implementation intervention based on an analysis of influencing factors, which include local stakeholder meetings, identification of nursing and medical opinion leaders in each site, a train-the-trainer day and standardised education and interactive workshops delivered by the opinion leaders during a 3 month period of time. Clinical practice outcomes will be collected retrospectively from medical records by independent chart auditors over the 2 month period following intervention delivery (patient level outcomes). In consenting hospitals, eligible patients will be recruited for a follow-up telephone interview conducted by trained researchers. A cost-effectiveness analysis and process evaluation using mixed-methods will be conducted. Sample size calculations are based on including 30 patients on average per department. Outcome assessors will be blinded to group allocation.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12612001286831 (date registered 12 December 2012).

Prediction of periventricular leukomalacia occurrence in neonates after heart surgery

This paper is concerned with predicting the occurrence of periventricular leukomalacia (PVL) using vital and blood gas data which are collected over a period of 12 h after the neonatal cardiac surgery. A data mining approach has been employed to generate a set of rules for classification of subjects as healthy or PVL affected. In view of the fact that blood gas and vital data have different sampling rates, in this study we have divided the data into two categories: 1) high resolution (vital), and 2) low resolution (blood gas), and designed a separate classifier based on each data category. The developed algorithm is composed of several stages; first, a feature pool has been extracted from each data category and the extracted features have been ranked based on the data reliability and their mutual information content with the output. An optimal feature subset with the highest discriminative capability has been formed using simultaneous maximization of the class separability measure and mutual information of a set. Two separate decision trees (DTs) have been developed for the classification purpose and more importantly to discover hidden relationships that exist among the data to help us better understand PVL pathophysiology. The DT result shows that high amplitude 20 min variations and low sample entropy in the vital data and the defined out of range index as well as maximum rate of change in blood gas data are important factors for PVL prediction. Low sample entropy represents lack of variability in hemodynamic measurement, and constant blood pressure with small fluctuations is an important indicator of PVL occurrence. Finally, using the different time frames of data collection, we show that the first 6 h of data contain sufficient information for PVL occurrence prediction.