Reducing accident death rates in children and young adults: the contribution of hospital care. Steering Committee of the Major Trauma Outcome Study Group.

OBJECTIVE: To assess the contribution of trauma care to the recent decline in accident death rates among children and young people. DESIGN: Logistic regression modelling of temporal trends in the probability of death in patients admitted to hospital for the treatment of severe injury. SETTING: Hospitals participating the United Kingdom major trauma outcome study. SUBJECTS: 3230 patients with an injury severity score of 16 or more, who were admitted for more than three days, transferred or admitted to intensive care, or died from their injuries. MAIN OUTCOME MEASURES: Death or survival in hospital within three months of injury. RESULTS: Over the seven year period 1989-95 there was a substantial decline in the probability of death among children and young adults admitted to hospital after severe injury. The overall estimate of the reduction in the odds of death was 16% per year (odds ratio for the yearly trend 0.84; 95% confidence interval 0.79 to 0.89). This decline did not differ significantly between age groups. (0-4 years 0.79; 5-14 years 0.87; 15-24 years 0.83). CONCLUSIONS: Reductions in hospital case fatality have made an important contribution to reaching the Health of the Nation targets. The contribution of hospital care in the reduction of accident mortality should be taken into account in decisions about the allocation of resources to preventive and curative services.     

Improving the care of patients with major trauma in the accident and emergency department.

OBJECTIVE--To determine whether improvement in the care of victims of major trauma could be made by using the revised trauma score as a triage tool to help junior accident and emergency doctors rapidly identify seriously injured patients and thereby call a senior accident and emergency specialist to supervise their resuscitation. DESIGN--Comparison of results of audit of management of all seriously injured patients before and after these measures were introduced. SETTING--Accident and emergency department in an urban hospital. PATIENTS--All seriously injured patients (injury severity score greater than 15) admitted to the department six months before and one year after introduction of the measures. RESULTS--Management errors were reduced from 58% (21/36) to 30% (16/54) (p less than 0.01). Correct treatment rather than improvement in diagnosis or investigation accounted for almost all the improvement. CONCLUSIONS--The management of seriously injured patients in the accident and emergency department can be improved by introducing two simple measures: using the revised trauma score as a triage tool to help junior doctors in the accident and emergency department rapidly identify seriously injured patients, and calling a senior accident and emergency specialist to supervise the resuscitation of all seriously injured patients. IMPLICATIONS--Care of patients in accident and emergency departments can be improved considerably at no additional expense by introducing two simple measures.     

The Low Fall as a Surrogate Marker of Frailty Predicts Long-Term Mortality in Older Trauma Patients

Background

Frailty is associated with adverse outcomes including disability, mortality and risk of falls. Trauma registries capture a broad range of injuries. However, frail patients who fall comprise a large proportion of the injuries occurring in ageing populations and are likely to have different outcomes compared to non-frail injured patients. The effect of frail fallers on mortality is under-explored but potentially significant. Currently, many trauma registries define low falls as less than three metres, a height that is likely to include non-frailty falls. We hypothesized that the low fall from less than 0.5 metres, including same-level falls, is a surrogate marker of frailty and predicts long-term mortality in older trauma patients.

Methods

Using data from the Singapore National Trauma Registry, 2011–2013, matched till September 2014 to the death registry, we analysed adults aged over 45 admitted via the emergency department in public hospitals sustaining blunt injuries with an injury severity score (ISS) of 9 or more, excluding isolated hip fractures from same-level falls in the over 65. Patients injured by a low fall were compared to patients injured by high fall and other blunt mechanisms. Logistic regression was used to analyze 12-month mortality, controlling for mechanism of injury, ISS, revised trauma score (RTS), co-morbidities, gender, age and age-gender interaction. Different low fall height definitions, adjusting for injury regions, and analyzing the entire adult cohort were used in sensitivity analyses and did not change our findings.

Results

Of the 8111 adults in our cohort, patients who suffered low falls were more likely to die of causes unrelated to their injuries (p<0.001), compared to other blunt trauma and higher fall heights. They were at higher risk of 12-month mortality (OR 1.75, 95% CI 1.18–2.58, p = 0.005), independent of ISS, RTS, age, gender, age-gender interaction and co-morbidities. Falls that were higher than 0.5m did not show this pattern. Males were at higher risk of mortality after low falls. The effect of age on mortality started at age 55 for males, and age 70 for females, and the difference was attributable to the additional mortality in male low-fallers.

Conclusions

The low fall mechanism can optimize prediction of long-term mortality after moderate and severe injury, and may be a surrogate marker of frailty, complementing broader-based studies on aging.     

Effectiveness of a regional trauma system in reducing mortality from major trauma: before and after study.

OBJECTIVE: To assess the effect of the development of an experimental trauma centre and regional trauma system on the survival of patients with major trauma. DESIGN: Controlled before and after study examining outcomes between 1990 and 1993, spanning the introduction of the system in 1991-2. SETTING: Trauma centre in North Staffordshire Royal Infirmary and five associated district general hospitals in the North West Midlands regional trauma system, and two control regions in Lancashire and Humberside. SUBJECTS: All trauma patients taken by the ambulance services serving the regions or arriving other than by ambulance with injury severity scores > 15, whether or not they had vital signs on arrival at hospital. MAIN OUTCOME MEASURES: Survival rates standardised for age, severity of injury, and revised trauma score. RESULTS: In 1990, 33% of major trauma patients in the experimental region were taken to the trauma centre, and by 1993 this had risen to only 39%. Crude death rates changed by the same amount in the control regions (46.5% in 1990-1 to 44.4% in 1992-3) as in the experimental region (44.8% to 41.3%). After standardisation, the estimated change in the probability of dying in the experimental region compared with the control regions was -0.8% per year (95% confidence interval -3.6% to 2.2%); for out of hours care, the change was 1.6% per year (-2.3% to 5.6%), and, for multiply injured patients, the change was -1.6% (-6.1% to 2.6%). CONCLUSION: Any reductions in mortality from regionalising major trauma care in shire areas of England would probably be modest compared with reports from the United States.     

Injuries from antipersonnel mines: the experience of the International Committee of the Red Cross.

OBJECTIVE--To describe and quantify patterns of injury from antipersonnel mines in terms of distribution of injury, drain on surgical resources, and residual disability. DESIGN--Retrospective analysis. SETTING--Two hospitals for patients injured in war. SUBJECTS--757 patients with injuries from antipersonnel mines. MAIN OUTCOME MEASURES--Distribution and number of injuries; number of blood transfusions; number of operations; disability. RESULTS--Pattern 1 injury results from standing on a buried mine. These patients usually sustain traumatic amputation of the foot or leg; they use most surgical time and blood and invariably require surgical amputation of one or both lower limbs. Pattern 2 injury is a more random collection of penetrating injuries caused by multiple fragments from a mine triggered near the victim. The lower limb is injured but there is less chance of traumatic amputation or subsequent surgical amputation. Injuries to the head, neck, chest, or abdomen are common. Pattern 3 injury results from handling a mine: the victim sustains severe upper limb injuries with associated face injuries. Eye injuries are common in all groups. CONCLUSIONS--Patients who survive standing on a buried mine have greatest disability. Non-combatants are at risk from these weapons; in developing countries their social and economic prospects after recovery from amputation are poor.     

Etiology of shock in blunt trauma.

Patients who have suffered blunt trauma and present in shock of uncertain cause represent a problem frequently encountered by emergency physicians. A retrospective review of the charts of 879 patients who had suffered blunt trauma and presented to a regional trauma unit over a 44-month period revealed that 154 of the patients had presented to either a hospital or the trauma unit in shock. The most common causes of shock when a single source of hemorrhage was identified were, in order of decreasing frequency, intraperitoneal hemorrhage, pelvic or other musculoskeletal fractures, thoracic hemorrhage, severe head injury and spinal cord injury. Severe head injuries accounted for only 8% of the single-source cases and contributed to shock in only seven of the remaining cases.     

Survey of intensive care of severely head injured patients in the United Kingdom.

OBJECTIVES--To study practice in intensive care of patients with severe head injury in neurosurgical referral centres in United Kingdom. DESIGN--Structured telephone interview of senior nursing staff in intensive care unit of adult neurosurgical referral centre. SETTING--39 intensive care units in hospitals that accepted acute head injuries for specialist neurosurgical management, identified from Medical Directory and information from professional bodies. MAIN OUTCOME MEASURES--Details of organisation and administration of intensive care and patterns of monitoring and treatment for patients admitted with severe head injury. RESULTS--Patients were managed in specialist neurosurgical intensive care units in 21 of the centres and in general intensive care units in 18. Their intensive care was coordinated by an anaesthetist in 25 units and by a neurosurgeon in 12. Annual case-load varied between units: 20 received > 100 patients, 12 received 50-100, and seven received 25-49. Monitoring and treatment varied considerably between centres. Invasive arterial pressure monitoring was used routinely in 36 units, but central venous pressure monitoring was routinely used in 24 and intracranial pressure was routinely monitored in only 19. Corticosteroids were used to treat intracranial hypertension in 19 units. Seventeen units routinely aimed for arterial carbon dioxide pressure of 3.3-4.0 kPa, and one unit still used severe hyperventilation to a pressure of < 3.3 kPa. CONCLUSION--The intensive care of patients with acute head injuries varied widely between the centres surveyed. Rationalisation of the intensive care of severe head injury with the production of widely accepted guidelines ought to improve the quality of care.     

Traumatic optic neuropathy: a review of 61 patients

The outcome of traumatic optic neuropathy was evaluated following penetrating and blunt injuries to assess the effect of treatment options, including high-dose steroids, surgical intervention, and observation alone. Factors that affected improvement in visual acuity were identified and quantified. Sixty-one consecutive, nonrandomized patients presenting with visual loss after facial trauma between 1984 and 1996 were assessed for outcome. Pretreatment and posttreatment visual acuities were compared using a standard ophthalmologic conversion from the values of no light perception, light perception, hand motion, finger counting, and 20/800 down to 20/15 to a logarithm of the minimum angle of resolution (log MAR). The percentage of patients showing visual improvement and the degree of improvement were calculated for each patient group and treatment method. Measurements of visual acuity are in log MAR units +/- standard error of the mean.Patients who sustained penetrating facial trauma (n = 21) had worse outcomes than patients with blunt trauma (n = 40). Improvement in visual acuity after treatment was seen in 19 percent of patients with penetrating trauma compared with 45 percent of patients with blunt trauma (p < 0.05). Furthermore, patients with penetrating trauma improved less than those with blunt trauma, with a mean improvement of 0.4 +/- 0.23 log MAR compared with 1.1 +/- 0.24 in blunt-trauma patients (p = 0.03). The patients with blunt trauma underwent further study. There was no significant difference in improvement of visual acuity in patients treated with surgical versus nonsurgical methods; however, 83 percent of patients without orbital fractures had improvement compared with 38 percent of patients with orbital fractures (p < 0.05). The mean improvement in patients without orbital fractures was 1.8 +/- 0.65 log MAR compared with 0.95 +/- 0.26 in patients with orbital fractures (p = 0.1). Twenty-seven percent of patients who had no light perception on presentation experienced improvement in visual acuity after treatment compared with 100 percent of patients who had light perception on admission (p < 0.05). The mean improvement in patients who were initially without light perception was 0.85 +/- 0.29 log MAR compared with 1.77 +/- 0.35 in patients who had light perception (p < 0.05). There were no significant differences in improvement of visual acuity when analyzing the effect of patient age and timing of surgery. Patients who sustain penetrating trauma have a worse prognosis than those with blunt trauma. The presence of no light perception and an orbital fracture are poor prognostic factors in visual loss following blunt facial trauma. It seems that clinical judgment on indication and timing of surgery, and not absolute criteria, should be used in the management of traumatic optic neuropathy.     

Review of pancreatic trauma.

In reviewing the literature on pancreatic trauma (1,984 cases), I found that it resulted from penetrating trauma in 73% and blunt trauma in 27% of cases. Associated injuries were common (average 3.0 per patient). Increased mortality was associated with shotgun wounds, an increasing number of associated injuries, the proximity of the injury to the head of the pancreas, preoperative shock, and massive hemorrhage. High mortality was found for total pancreatectomy, duct reanastomosis, and lack of surgical treatment, with lower mortality for Roux-en-Y anastomoses, suture and drainage, distal pancreatectomy, and duodenal exclusion and diverticulization techniques. Most patients required drainage only. The preoperative diagnosis of pancreatic trauma is difficult, with the diagnosis usually made during surgical repair for associated injuries. Blood studies such as amylase levels, diagnostic peritoneal lavage, and plain radiographs are not reliable. Computed tomographic scanning may be superior, but data are limited.     

Variation in emergency department use of cervical spine radiography for alert,stable trauma patients

OBJECTIVE: To, assess the emergency department use of cervical spine radiography for alert, stable adult trauma patients in terms of utilization, yield for injury and variation in practices among hospitals and physicians. DESIGN: Retrospective survey of health records. SETTING: Emergency departments of 6 teaching and 2 community hospitals in Ontario and British Columbia. PATIENTS: Consecutive alert, stable adult trauma patients seen with potential cervical spine injury between July 1, 1994, and June 30, 1995. MAIN OUTCOME MEASURES: Total number of eligible patients, referral for cervical spine radiography (overall, by hospital and by physician), presence of cervical spine injury, patient characteristics and hospitals associated with use of radiography. RESULTS: Of 6855 eligible patients, cervical spine radiography was ordered for 3979 (58.0%). Only 60 (0.9%) patients were found to have an acute cervical spine injury (fracture, dislocation or ligamentous instability); 98.5% of the radiographic films were negative for any significant abnormality. The demographic and clinical characteristics of the patients were similar across the 8 hospitals, and no cervical spine injuries were missed. Significant variation was found among the 8 hospitals in the rate of ordering radiography (p < 0.0001), from a low of 37.0% to a high of 72.5%. After possible differences in case severity and patient characteristics at each hospital were controlled for, logistic regression analysis revealed that 6 of the hospitals were significantly associated with the use of radiography. At 7 hospitals, there was significant variation in the rate of ordering radiography among the attending emergency physicians (p < 0.05), from a low of 15.6% to a high of 91.5%. CONCLUSIONS: Despite considerable variation among institutions and individual physicians in the ordering of cervical spine radiography for alert, stable trauma patients with similar characteristics, no cervical spine injuries were missed. The number of radiographic films showing signs of abnormality was extremely low at all hospitals. The findings suggest that cervical spine radiography could be used more efficiently, possibly with the help of a clinical decision rule.     

Derivation and Validation of Two Decision Instruments for Selective Chest CT in Blunt Trauma: A Multicenter Prospective Observational Study (NEXUS Chest CT)

Background

Unnecessary diagnostic imaging leads to higher costs, longer emergency department stays, and increased patient exposure to ionizing radiation. We sought to prospectively derive and validate two decision instruments (DIs) for selective chest computed tomography (CT) in adult blunt trauma patients.

Methods and Findings

From September 2011 to May 2014, we prospectively enrolled blunt trauma patients over 14 y of age presenting to eight US, urban level 1 trauma centers in this observational study. During the derivation phase, physicians recorded the presence or absence of 14 clinical criteria before viewing chest imaging results. We determined injury outcomes by CT radiology readings and categorized injuries as major or minor according to an expert-panel-derived clinical classification scheme. We then employed recursive partitioning to derive two DIs: Chest CT-All maximized sensitivity for all injuries, and Chest CT-Major maximized sensitivity for only major thoracic injuries (while increasing specificity). In the validation phase, we employed similar methodology to prospectively test the performance of both DIs.We enrolled 11,477 patients—6,002 patients in the derivation phase and 5,475 patients in the validation phase. The derived Chest CT-All DI consisted of (1) abnormal chest X-ray, (2) rapid deceleration mechanism, (3) distracting injury, (4) chest wall tenderness, (5) sternal tenderness, (6) thoracic spine tenderness, and (7) scapular tenderness. The Chest CT-Major DI had the same criteria without rapid deceleration mechanism. In the validation phase, Chest CT-All had a sensitivity of 99.2% (95% CI 95.4%–100%), a specificity of 20.8% (95% CI 19.2%–22.4%), and a negative predictive value (NPV) of 99.8% (95% CI 98.9%–100%) for major injury, and a sensitivity of 95.4% (95% CI 93.6%–96.9%), a specificity of 25.5% (95% CI 23.5%–27.5%), and a NPV of 93.9% (95% CI 91.5%–95.8%) for either major or minor injury. Chest CT-Major had a sensitivity of 99.2% (95% CI 95.4%–100%), a specificity of 31.7% (95% CI 29.9%–33.5%), and a NPV of 99.9% (95% CI 99.3%–100%) for major injury and a sensitivity of 90.7% (95% CI 88.3%–92.8%), a specificity of 37.9% (95% CI 35.8%–40.1%), and a NPV of 91.8% (95% CI 89.7%–93.6%) for either major or minor injury. Regarding the limitations of our work, some clinicians may disagree with our injury classification and sensitivity thresholds for injury detection.

Conclusions

We prospectively derived and validated two DIs (Chest CT-All and Chest CT-Major) that identify blunt trauma patients with clinically significant thoracic injuries with high sensitivity, allowing for a safe reduction of approximately 25%–37% of unnecessary chest CTs. Trauma evaluation protocols that incorporate these DIs may decrease unnecessary costs and radiation exposure in the disproportionately young trauma population.     

Trauma services requirements in a district general hospital serving a rural area.

OBJECTIVE--To assess the demands made on a regional trauma centre by a district trauma unit. DESIGN--Two part study. (1) Prospective analysis of one month''s workload. (2) Retrospective analysis of one year''s workload by using a computer based records system. Comparison of two sets of results. SETTING--Accident unit in Gwynedd Hospital, Bangor. PATIENTS--(1) All patients who attended the accident unit in August 1988. (2) All patients who attended the accident unit in the calendar year April 1988-April 1989. MAIN OUTCOME MEASURE--Workload of a district trauma unit. RESULTS--In August 1988 there were 2325 attendances; 2302 of these were analysed. In all, 1904 attendances were for trauma; 213 patients were admitted to the trauma ward and 103 required an operation that entailed incision. Patients who attended the unit had a mean (range) injury severity score of 2-13 (0-25). Only two patients had injuries that a district general hospital would not be expected to cope with (injury severity score greater than 20). In the year April 1988-April 1989, 21,007 patients attended the unit. In all, 17,958 attendances were for orthopaedic injuries or injuries caused by an accident; 1966 patients were admitted to the unit. CONCLUSIONS--Most trauma is musculoskeletal and relatively minor according to the injury severity score. All but a few injuries can be managed in district general hospitals. In their recent report the Royal College of Surgeons has overestimated the requirements that a British district general hospital would have of a regional trauma centre.     

Annual league tables of mortality in neonatal intensive care units: longitudinal study

Objective: To assess whether crude league tables of mortality and league tables of risk adjusted mortality accurately reflect the performance of hospitals. Design: Longitudinal study of mortality occurring in hospital. Setting: 9 neonatal intensive care units in the United Kingdom. Subjects: 2671 very low birth weight or preterm infants admitted to neonatal intensive care units between 1988 and 1994. Main outcome measures: Crude hospital mortality and hospital mortality adjusted using the clinical risk index for babies (CRIB) score. Results: Hospitals had wide and overlapping confidence intervals when ranked by mortality in annual league tables; this made it impossible to discriminate between hospitals reliably. In most years there was no significant difference between hospitals, only random variation. The apparent performance of individual hospitals fluctuated substantially from year to year. Conclusions: Annual league tables are not reliable indicators of performance or best practice; they do not reflect consistent differences between hospitals. Any action prompted by the annual league tables would have been equally likely to have been beneficial, detrimental, or irrelevant. Mortality should be compared between groups of hospitals using specific criteria—such as differences in the volume of patients, staffing policy, training of staff, or aspects of clinical practice—after adjusting for risk. This will produce more reliable estimates with narrower confidence intervals, and more reliable and rapid conclusions.

Key messages

• League tables are being used increasingly to evaluate hospital performance in the United Kingdom
• In annual league tables the rankings of nine neonatal intensive care units in different hospitals had wide and overlapping confidence intervals and their rankings fluctuated substantially over six years
• Annual league tables of hospital mortality were inherently unreliable for comparing hospital performance or for indicating best practices
• The UK government’s commitment to using annual league tables of outcomes such as mortality to monitor services and the spread of best practices should be reconsidered
• Prospective studies of risk adjusted outcome in hospitals grouped according to specific characteristics would provide better information and be a better use of resources

     

Obstetric Anaesthesia Services in the United Kingdom

In a survey of obstetric anaesthetic services in the United Kingdom questionnaires were sent to 398 hospital maternity units and 347 general-practitioner maternity units, of which 344 and 272 respectively were returned. Many hospitals were unable to provide an anaesthetist for obstetric surgery only, and few consultant anaesthetist sessions were allocated to obstetric surgery, particularly in regional hospitals in England and Wales. Constant supervision of junior anaesthetic staff with under 12 months'' experience was lacking in several hospitals. Endotracheal intubation is widely used throughout the United Kingdom. Though regional analgesic techniques are used by most anaesthetists it is impossible to provide a 24-hour regional analgesic service in all but a few hospitals.     

Management of hepatic injury.

Liver injuries may be due to either blunt or penetrating trauma to the thorax or abdomen. Specific treatment depends on the site and extent of hepatic injury. Following resuscitation with intravenous fluids and blood as needed, surgical therapy is directed to provide hemostasis, remove necrotic liver tissue and promote adequate external drainage in the postoperative period. While local measures are usually sufficient, complex hepatic wounds may require extensive resection and vascular ligature or repair.     

Injuries to the Liver: Analysis of 20 Cases

Twenty cases of liver injury among 55 consecutive cases of abdominal injury submitted to laparotomy over a four-year period are reported. Forty-four of the cases were blunt injuries, and the cases of liver injury were in this group. Road traffic accidents accounted for 37 of the 44 cases and 17 of the 20 liver injuries. Except in two cases injury to the liver was associated with injury to other organs. Severe chest injury was found in 40% of the cases and serious skeletal injury in 45%. The overall mortality in blunt injury to the liver was 20% (4 cases) and was directly attributable to the liver injury in only one case.Liver injuries are classified as minor or major according to the depth of the wound and the associated destruction of liver tissue. Liver resection is advocated for major injuries. Right hepatic lobectomy was performed on five occasions and three of the patients survived. Death in the other two was due to associated injuries. The remarkable regenerative capacity of the liver is emphasized.     

Lower urinary tract injuries following blunt trauma: a review of contemporary management

Lower urinary tract trauma, although relatively uncommon in blunt trauma, can lead to significant morbidity when diagnosed late or left untreated; urologists may only encounter a handful of these injuries in their career. This article reviews the literature and reports on the management of these injuries, highlighting the issues facing clinicians in this subspecialty. Also presented is a structured review detailing the mechanisms, classification, diagnosis, management, and complications of blunt trauma to the bladder and urethra. The prognosis for bladder rupture is excellent when treated. Significant intraperitoneal rupture or involvement of the bladder neck mandates surgical repair, whereas smaller extraperitoneal lacerations may be managed with catheterization alone. With the push for management of trauma patients in larger centers, urologists in these hospitals are seeing increasing numbers of lower urinary tract injuries. Prospective analysis may be achieved in these centers to address the current lack of Level 1 evidence.     

‘Poking the skunk’: Ethical and medico‐legal concerns in research about patients’ experiences of medical injury

Improving how health care providers respond to medical injury requires an understanding of patients’ experiences. Although many injured patients strongly desire to be heard, research rarely involves them. Institutional review boards worry about harming participants by asking them to revisit traumatic events, and hospital staff worry about provoking lawsuits. Institutions’ reluctance to approve this type of research has slowed progress toward responses to injuries that are better able to meet patients’ needs. In 2015–2016, we were able to surmount these challenges and interview 92 injured patients and families in the USA and New Zealand. This article explores whether the ethical and medico‐legal concerns are, in fact, well‐founded. Consistent with research about trauma‐research‐related distress, our participants’ accounts indicate that the pervasive fears about retraumatization are unfounded. Our experience also suggests that because being heard is an important (but often unmet) need for injured patients, talking provides psychological benefits and may decrease rather than increase the impetus to sue. Our article makes recommendations to institutional review boards and researchers. The benefits to responsibly conducted research with injured patients outweigh the risks to participants and institutions.     

The burden of traumatic brain injury from low-energy falls among patients from 18 countries in the CENTER-TBI Registry: A comparative cohort study

BackgroundTraumatic brain injury (TBI) is an important global public health burden, where those injured by high-energy transfer (e.g., road traffic collisions) are assumed to have more severe injury and are prioritised by emergency medical service trauma triage tools. However recent studies suggest an increasing TBI disease burden in older people injured through low-energy falls. We aimed to assess the prevalence of low-energy falls among patients presenting to hospital with TBI, and to compare their characteristics, care pathways, and outcomes to TBI caused by high-energy trauma.Methods and findingsWe conducted a comparative cohort study utilising the CENTER-TBI (Collaborative European NeuroTrauma Effectiveness Research in TBI) Registry, which recorded patient demographics, injury, care pathway, and acute care outcome data in 56 acute trauma receiving hospitals across 18 countries (17 countries in Europe and Israel). Patients presenting with TBI and indications for computed tomography (CT) brain scan between 2014 to 2018 were purposively sampled. The main study outcomes were (i) the prevalence of low-energy falls causing TBI within the overall cohort and (ii) comparisons of TBI patients injured by low-energy falls to TBI patients injured by high-energy transfer—in terms of demographic and injury characteristics, care pathways, and hospital mortality. In total, 22,782 eligible patients were enrolled, and study outcomes were analysed for 21,681 TBI patients with known injury mechanism; 40% (95% CI 39% to 41%) (8,622/21,681) of patients with TBI were injured by low-energy falls. Compared to 13,059 patients injured by high-energy transfer (HE cohort), the those injured through low-energy falls (LE cohort) were older (LE cohort, median 74 [IQR 56 to 84] years, versus HE cohort, median 42 [IQR 25 to 60] years; p < 0.001), more often female (LE cohort, 50% [95% CI 48% to 51%], versus HE cohort, 32% [95% CI 31% to 34%]; p < 0.001), more frequently taking pre-injury anticoagulants or/and platelet aggregation inhibitors (LE cohort, 44% [95% CI 42% to 45%], versus HE cohort, 13% [95% CI 11% to 14%]; p < 0.001), and less often presenting with moderately or severely impaired conscious level (LE cohort, 7.8% [95% CI 5.6% to 9.8%], versus HE cohort, 10% [95% CI 8.7% to 12%]; p < 0.001), but had similar in-hospital mortality (LE cohort, 6.3% [95% CI 4.2% to 8.3%], versus HE cohort, 7.0% [95% CI 5.3% to 8.6%]; p = 0.83). The CT brain scan traumatic abnormality rate was 3% lower in the LE cohort (LE cohort, 29% [95% CI 27% to 31%], versus HE cohort, 32% [95% CI 31% to 34%]; p < 0.001); individuals in the LE cohort were 50% less likely to receive critical care (LE cohort, 12% [95% CI 9.5% to 13%], versus HE cohort, 24% [95% CI 23% to 26%]; p < 0.001) or emergency interventions (LE cohort, 7.5% [95% CI 5.4% to 9.5%], versus HE cohort, 13% [95% CI 12% to 15%]; p < 0.001) than patients injured by high-energy transfer. The purposive sampling strategy and censorship of patient outcomes beyond hospital discharge are the main study limitations.ConclusionsWe observed that patients sustaining TBI from low-energy falls are an important component of the TBI disease burden and a distinct demographic cohort; further, our findings suggest that energy transfer may not predict intracranial injury or acute care mortality in patients with TBI presenting to hospital. This suggests that factors beyond energy transfer level may be more relevant to prehospital and emergency department TBI triage in older people. A specific focus to improve prevention and care for patients sustaining TBI from low-energy falls is required.

In a cohort study, Fiona Lecky and colleagues investigate the factors associated with traumatic brain injury resulting from low energy falls compared with injuries from high energy transfer mechanisms among patients across Europe and Israel.     

Quantitative analysis of brain microstructure following mild blunt and blast trauma

We induced mild blunt and blast injuries in rats using a custom-built device and utilized in-house diffusion tensor imaging (DTI) software to reconstruct 3-D fiber tracts in brains before and after injury (1, 4, and 7 days). DTI measures such as fiber count, fiber length, and fractional anisotropy (FA) were selected to characterize axonal integrity. In-house image analysis software also showed changes in parameters including the area fraction (AF) and nearest neighbor distance (NND), which corresponded to variations in the microstructure of Hematoxylin and Eosin (H&E) brain sections. Both blunt and blast injuries produced lower fiber counts, but neither injury case significantly changed the fiber length. Compared to controls, blunt injury produced a lower FA, which may correspond to an early onset of diffuse axonal injury (DAI). However, blast injury generated a higher FA compared to controls. This increase in FA has been linked previously to various phenomena including edema, neuroplasticity, and even recovery. Subsequent image analysis revealed that both blunt and blast injuries produced a significantly higher AF and significantly lower NND, which correlated to voids formed by the reduced fluid retention within injured axons. In conclusion, DTI can detect subtle pathophysiological changes in axonal fiber structure after mild blunt and blast trauma. Our injury model and DTI method provide a practical basis for studying mild traumatic brain injury (mTBI) in a controllable manner and for tracking injury progression. Knowledge gained from our approach could lead to enhanced mTBI diagnoses, biofidelic constitutive brain models, and specialized pharmaceutical treatments.