Maximum Abbreviated Injury Scale Research Articles

Reality of treatment for severely injured patients: are there age-specific differences?

BackgroundMajor trauma and its consequences are one of the leading causes of death worldwide across all age groups. Few studies have conducted comparative age-specific investigations. It is well known that children respond differently to major trauma than elderly patients due to physiological differences. The aim of this study was to analyze the actual reality of treatment and outcomes by using a matched triplet analysis of severely injured patients of different age groups.MethodsData from the TraumaRegister DGU® were analyzed. A total of 56,115 patients met the following inclusion criteria: individuals with Maximum Abbreviated Injury Scale > 2 and < 6, primary admission, from German-speaking countries, and treated from 2011–2020. Furthermore, three age groups were defined (child: 3–15 years; adult: 20–50 years; and elderly: 70–90 years). The matched triplets were defined based on the following criteria: 1. exact injury severity of the body regions according to the Abbreviated Injury Scale (head, thorax, abdomen, extremities [including pelvis], and spine) and 2. level of the receiving hospital.ResultsA total of 2,590 matched triplets could be defined. Traffic accidents were the main cause of severe injury in younger patients (child: 59.2%; adult: 57.9%). In contrast, low falls (from < 3 m) were the most frequent cause of accidents in the elderly group (47.2%). Elderly patients were least likely to be resuscitated at the scene. Both children and elderly patients received fewer therapeutic interventions on average than adults. More elderly patients died during the clinical course, and their outcome was worse overall, whereas the children had the lowest mortality rate.ConclusionsFor the first time, a large patient population was used to demonstrate that both elderly patients and children may have received less invasive treatment compared with adults who were injured with exactly the same severity (with the outcomes of these two groups being opposite to each other). Future studies and recommendations should urgently consider the different age groups.

Pregnancy is associated with more severe injuries from motor vehicle crashes

ObjectiveWhether pregnancy is associated with severe injuries from motor vehicle crashes (MVCs) remains unclear. This study aimed to investigate the potential relationship between pregnancy and severity of injuries from MVCs. MethodsWe identified a total of 23,559 pregnant women victims who encountered MVCs during pregnancy as well as 94,236 age- and calendar year-at MVC matched non-pregnant women victims that are also involved in MVCs. Injury severity was assessed using the Maximum Abbreviated Injury Scale (MAIS) based on the diagnosis of medical claims after MVCs. Multinomial logistic regression models were used to estimate the odds ratio and corresponding 95 % CI of injury severity levels associated with pregnancy. ResultsPregnant women had a significantly higher risk of both severe (adjusted odds ratio, aOR = 1.79, 95 % CI = 1.54–2.08) and mild injuries (aOR = 8.63, 95 % CI = 8.21–9.07) following MVCs as compared to non-pregnant women victims. Particularly, pregnant women who were riding scooters had an increased risk of severe injury (aOR = 4.25, 95 % CI = 3.58–5.04). In addition, pregnant women who experienced MVC but without any injury were more likely to visit a clinic than non-pregnant MVC victims. ConclusionPregnant women victims, particularly those who were riding scooters involved in MVCs suffered from a higher risk of severe injury as compared to their non-pregnant counterparts. Our findings suggest that women should consider avoiding riding a scooter and must use restrictive devices during pregnancy, which would help reduce the severity of injuries sustained following an MVC.

Identifying the severely injured benefitting from a specific level of trauma care in an inclusive network: A multicentre retrospective study

IntroductionDefining major trauma (MT) with an Injury Severity Score (ISS) > 15 has limitations. This threshold is used for concentrating MT care in networks with multiple levels of trauma care. ObjectiveThis study aims to identify subgroups of severely injured patients benefiting on in-hospital mortality and non-fatal clinical outcome measures in an optimal level of trauma care. MethodsA multicentre retrospective cohort study on data of the Dutch National Trauma Registry, region South West, from January 1, 2015 until December 31, 2019 was conducted. Patients ≥ 16 years admitted within 48 h after trauma transported with (H)EMS to a level I trauma centre (TC) or a non-level I trauma facility with a Maximum Abbreviated Injury Scale (MAIS) ≥ 3 were included. Patients with burns or patients of ≥ 65 years with an isolated hip fracture were excluded. Logistic regression models were used for comparing level I with non-level I. Subgroup analysis were done for MT patients (ISS > 15) and non-MT patients (ISS 9–14). ResultsA total of 7,493 records were included. In-hospital mortality of patients admitted to a non-level I trauma facility did not differ significantly from patients admitted to the level I TC (adjusted Odds Ratio (OR): 0.94; 95% confidence interval (CI) 0.68–1.30). This was also applicable for MT patients (OR: 1.06; 95% CI 0.73–1.53) and non-MT patients (OR: 1.30; 95% CI (0.56–3.03). Hospital and ICU LOS were significantly shorter for patients admitted to a non-level I trauma facilities, and patients admitted to a non-level I trauma facility were more likely to be discharged home. Findings were confirmed for MT and non-MT patients, per injured body region. ConclusionAll levels of trauma care performed equally on in-hospital mortality among severely injured patients (MAIS ≥ 3), although patients admitted to the level I TC were more severely injured. Subgroups of patients by body region or ISS, with a survival benefit or more favorable clinical outcome measures were not identified. Subgroups analysis on clinical outcome measures across different levels of trauma care in an inclusive trauma network is too simplistic if subgroups are based on injuries in specific body region or ISS only.

Changes in patterns of traumatic brain injury in the Michigan Trauma Quality Improvement Program database early in the COVID-19 pandemic.

The authors' objective was to investigate the impact of the global COVID-19 pandemic on hospital presentation and process of care for the treatment of traumatic brain injuries (TBIs). Improved understanding of these effects will inform sociopolitical and hospital policies in response to future pandemics. The Michigan Trauma Quality Improvement Program (MTQIP) database, which contains data from 36 level I and II trauma centers in Michigan and Minnesota, was queried to identify patients who sustained TBI on the basis of head/neck Abbreviated Injury Scale (AIS) codes during the periods of March 13 through July 2 of 2017-2019 (pre-COVID-19 period) and March 13, 2020, through July 2, 2020 (COVID-19 period). Analyses were performed to detect differences in incidence, patient characteristics, injury severity, and outcomes. There was an 18% decrease in the rate of encounters with TBI in the first 8 weeks (March 13 through May 7), followed by a 16% increase during the last 8 weeks (May 8 through July 2), of our COVID-19 period compared with the pre-COVID-19 period. Cumulatively, there was no difference in the rates of encounters with TBI between the COVID-19 and pre-COVID-19 periods. Severity of TBI, as measured with maximum AIS score for the head/neck region and Glasgow Coma Scale score, was also similar between periods. During the COVID-19 period, a greater proportion of patients with TBI presented more than a day after sustaining their injuries (p = 0.046). COVID-19 was also associated with a doubling in the decubitus ulcer rate from 1.0% to 2.1% (p = 0.002) and change in the distribution of discharge status (p = 0.01). Multivariable analysis showed no differences in odds of death/hospice discharge, intensive care unit stay of at least a day, or need for a ventilator for at least a day between the COVID-19 and pre-COVID-19 periods. During the early months of the COVID-19 pandemic, the number of patients who presented with TBI was initially lower than in the years 2017-2019 prior to the pandemic. However, there was a subsequent increase in the rate of encounters with TBI, resulting in overall similar rates of TBI between March 13 through July 2 during the COVID-19 period and during the pre-COVID-19 period. The COVID-19 cohort was also associated with negative impacts on time to presentation, rate of decubitus ulcers, and discharge with supervision. Policies in response to future pandemics must consider the resources necessary to care for patients with TBI.

The Golden Hour of Casualty Care: Rapid Handoff to Surgical Team is Associated With Improved Survival in War-injured US Service Members.

To examine time from injury to initiation of surgical care and association with survival in US military casualties. Although the advantage of trauma care within the "golden hour" after an injury is generally accepted, evidence is scarce. This retrospective, population-based cohort study included US military casualties injured in Afghanistan and Iraq, January 2007 to December 2015, alive at initial request for evacuation with maximum abbreviated injury scale scores ≥2 and documented 30-day survival status after injury. Interventions: (1) handoff alive to the surgical team, and (2) initiation of first surgery were analyzed as time-dependent covariates (elapsed time from injury) using sequential Cox proportional hazards regression to assess how intervention timing might affect mortality. Covariates included age, injury year, and injury severity. Among 5269 patients (median age, 24 years; 97% males; and 68% battle-injured), 728 died within 30 days of injury, 68% within 1 hour, and 90% within 4 hours. Only handoffs within 1 hour of injury and the resultant timely initiation of emergency surgery (adjusted also for prior advanced resuscitative interventions) were significantly associated with reduced 24-hour mortality compared with more delayed surgical care (adjusted hazard ratios: 0.34; 95% CI: 0.14-0.82; P = 0.02; and 0.40; 95% CI: 0.20-0.81; P = 0.01, respectively). In-hospital waits for surgery (mean: 1.1 hours; 95% CI; 1.0-1.2) scarcely contributed ( P = 0.67). Rapid handoff to the surgical team within 1 hour of injury may reduce mortality by 66% in US military casualties. In the subgroup of casualties with indications for emergency surgery, rapid handoff with timely surgical intervention may reduce mortality by 60%. To inform future research and trauma system planning, findings are pivotal.

Cost-Benefit Analysis to Assess the Effectiveness of an External Airbag and Autonomous Emergency Braking System

One of the recent developments in safety systems is an external airbag installed on the front bumper of a vehicle and autonomous emergency braking system. In this paper, we propose a framework for a cost-benefit analysis of the external airbag and autonomous emergency braking system in order to validate its commercialization. Road traffic crash data obtained from the National Automotive Sampling System/Crashworthiness Data System (NASS/CDS) was used, and three different crash types related to frontal damage in vehicles were extracted to estimate the safety performance of an external airbag. An ordinal logistic regression model was applied to estimate the safety performance in terms of the reduced maximum abbreviated injury scale (MAIS) based on a reduction in the total delta-v following the installation of an external airbag. Given the estimated safety performance of the external airbag, a cost-benefit analysis is conducted. According to the results, the external airbag system saves 46% of occupants with MAIS 3+ injuries and prevents 40% of fatalities. Moreover, the benefit/cost ratios of the external airbag system range from 0.496 to 0.509 depending on the scenario. Lastly, sensitivity analyses were performed with important parameters, including the initial and maximum market penetration ratio and the price of the system.

Is prehospital intubation of severely injured children in accordance with guidelines?

BackgroundThe current German S3 guideline for polytrauma lists five criteria for prehospital intubation: apnea, severe traumatic brain injury (GCS ≤8), severe chest trauma with respiratory failure, hypoxia, and persistent hemodynamic instability. These guideline criteria, used in adults in daily practice, have not been previously studied in a collection of severely injured children. The aim of this study was to assess the extent to which the criteria are implemented in clinical practice using a multivariate risk analysis of severely injured children.MethodsData of 289,698 patients from the TraumaRegister DGU® were analyzed. Children meeting the following criteria were included: Maximum Abbreviated Injury Scale 3+, primary admission, German-speaking countries, years 2008–2017, and declaration of intubation. Since children show age-dependent deviating physiology, four age groups were defined (years old: 0–2; 3–6; 7–11; 12–15). An adult collective served as a control group (age: 20–50). After a descriptive analysis in the first step, factors leading to prehospital intubation in severely injured children were analyzed with a multivariate regression analysis.ResultsA total of 4489 children met the inclusion criteria. In this cohort, young children up to 2 years old had the significantly highest injury severity (Injury Severity Score: 21; p ≤ 0.001). Falls from both high (> 3 m) and low heights (< 3 m) were more common in children than in adults. The same finding applied to the occurrence of severe traumatic brain injury. When at least one intubation criterion was formally present, the group up to 6 years old was least likely to actually be intubated (61.4%; p ≤ 0.001). Multivariate regression analysis showed that Glasgow Coma Scale score ≤ 8 in particular had the greatest influence on intubation (odds ratio: 26.9; p ≤ 0.001).ConclusionsThe data presented here show for the first time that the existing criteria in the guideline for prehospital intubation are applied in clinical practice (approximately 70% of cases), compared to adults, in the vast majority of injured children. Although severely injured children still represent a minority of all injured patients, future guidelines should focus more on them and address them in a specialized manner.

Serious-to-fatal injury to second-row occupants in rear impacts using 1994–2020 field data

Objective Serious-to-fatal injury was analyzed for second-row children aged 0–14 years and adults aged 15 and older in rear impacts by body region, restraint use, and injury mechanism using field data collected by NHTSA. Method 1994–2015 NASS-CDS and 2017–2020 CISS data were used to investigate the rate for Maximum Abbreviated Injury Scale (MAIS) 3 + F injury in rear crashes involving 1994+ model year vehicles. All second-row occupants were included, irrespective of restraint use and ejection status. The data were analyzed by group: children (0–14 years old) and adults (15+ years old). All available electronic files for seriously injured second-row occupants in the rear impacts were reviewed for mechanism of injury. Results The rate of serious injury (MAIS 3 + F) for second-row occupants was 0.93% ± 0.36% in rear crashes; it was 0.76% ± 0.39% for children and 1.22% ± 0.40% for adults. There were 2.8 AIS 3+ injuries per seriously to fatally injured occupant on average. Most serious injuries occurred to the head in children and to the head and chest in adults. Restraint use was only 31.3% for all seriously injured second-row occupants in the rear impacts. It was 45.1% for children and 17.8% for adults. The overall rate of serious injury in rear impacts was 10.0 times higher when unrestrained than restrained overall; it was 5.6 times higher for children and 20.2 times higher in adults. The case review indicated that many young children were improperly restrained or placed in the incorrect child seat. More than 17% of second-row adults were ejected; all were unrestrained. The primary mechanism for child injury was related to intrusion (86.0%). About 14% was not related to intrusion; 12.3% involved the front seat rotating rearward into the child. The primary mechanisms for adult injury differed from those for children; 68.0% was related to intrusion, 21.6% was not related to intrusion, and 10.4% involved ground impact with ejection. Of the non-intrusion-related cases, 19.1% involved acceleration forces injuring the adult and 2.5% involved the front seat rotating rearward. Conclusions The primary mechanism for serious injury to second-row occupants in rear crashes was intrusion either by direct force, compression into front components, or acceleration into forward components. The front seat moving rearward was an infrequent cause for injury.

Young adults in motor vehicle collisions in Norway: user safety errors observed in majority of cases with severe or fatal injuries

PurposeWe performed a multidisciplinary investigation of young adults involved in motor vehicle collisions (MVCs) to elucidate injury mechanisms and the role of passive safety equipment such as seat belts and airbags.MethodsMVCs resulting in death or serious injuries to the driver or passengers aged 16–24 years in southeastern Norway during 2013–2016 were investigated upon informed consent. We assessed the crash scene, the motor vehicle (MV) interior and exterior, and analyzed data from medical records, forensic autopsies and reports from police and civil road authorities.ResultsThis study included 229 young adult occupants involved in 212 MVCs. The Maximum Abbreviated Injury Scale (MAIS) score was ≥2 in 111 occupants, of which 22 were fatalities. In 59% (65/111) of the cases with MAIS score ≥2 injuries, safety errors and occupant protection inadequacies were considered to have contributed to the injury outcome. Common errors were seatbelt non-use and misuse, carrying insecure luggage, and the seat back being too reclined. MAIS score ≥2 head/neck injuries were observed in side impacts despite correct seatbelt use, related to older MVs lacking side airbag curtains. The independent risk factors for MAIS score ≥2 injuries included not using a seatbelt, driving under the influence of alcohol or drugs, nighttime driving, side impacts, heavy collision partner, and MV deformation.ConclusionUser safety errors (not using a seatbelt, seatbelt misuse, excessive seat-back reclining, and insecure cargo) and a lack of occupant protection in older MVs resulted in young adults sustaining severe or fatal injuries in MVCs.

Age-based variability in the association between restraint use and injury type and severity in multi-occupant crashes

PurposePrevious studies have shown older adults receive relatively less protection from seat belts against fatal injuries, however it is unknown how seat belt protection against severe and torso injury changes with age. We estimated age-based variability in seat belt protection against fatal injuries, injuries with maximum abbreviated injury scale greater than two (MAIS 3+), and torso injuries. MethodsWe leveraged the Crash Outcome Data Evaluation System to analyze binary indicators of fatal, MAIS 3+, and torso injuries. Using a matched cohort design and conditional Poisson regression, we estimated age-based relative risks (RR) of the outcomes associated with seat belt use. ResultsOur results suggested that seat belts were highly protective against fatal injuries for all ages. For ages 16–30, seat belt use was associated with 66% lower risk of MAIS3+ injury (RR 0.34, 95% CI 0.30, 0.38) for occupants of the same vehicle, whereas for ages 75 and older, seat belt use was associated with 38% lower risk of MAIS3+ injury (RR 0.62; 95% CI 0.45, 0.86) for occupants in the same vehicle. The association between restraint use and torso injury also attenuated with age. ConclusionsIn multi-occupant crashes, seat belts were highly protective against fatal and MAIS3+ injury, however seat belt protection against MAIS3+ and torso injury attenuated with age.

Effects of muscle quantity and bone mineral density on injury and outcomes in older adult motor vehicle crash occupants

Objectives: Quantify the independent and combined effects of abdominal muscle quantity and lumbar bone mineral density (BMD) on injury risk and in-hospital outcomes in severely injured motor vehicle crash (MVC) occupants ages 50 and older. Methods: Skeletal muscle area measurements of MVC occupants were obtained through semi-automated segmentation of an axial computed tomography (CT) slice at the L3 vertebra. An occupant height-normalized Skeletal Muscle Index (SMI) was calculated - a defining metric of sarcopenia and low muscle mass (sarcopenia thresholds: <38.5 cm2/m2 females; <52.4 cm2/m2 males). Lumbar BMD was obtained using a validated, phantomless CT calibration method (osteopenia threshold: <145 mg/cm3). SMI and BMD values were used to categorize occupants, and logistic regression was used to associate sarcopenia, osteopenia, and osteosarcopenia predictors to injury outcomes (e.g., Injury Severity Score (ISS), maximum Abbreviated Injury Scale (MAIS) score, fractures) and hospital outcomes (e.g., length of stay, ICU days). Results: Of the 336 occupants, 210 (63%) were female (mean ± SD: age 66.3 ± 10.6). SMI was 41.7 ± 8.0 cm2/m2 in females and 51.2 ± 10.8 cm2/m2 in males. Based on SMI, 40% of females and 55% of males were classified as sarcopenic. BMD was 163.2 ± 38.3 mg/cm3 in females and 164.1 ± 35.4 mg/cm3 in males, with 41% of females and 33% of males classified as osteopenic. Prevalence of both conditions (osteosarcopenia) was similar between females (21%) and males (22%). Incidence of low SMI and BMD increased with age. Sarcopenic individuals were less likely to sustain a MAIS 2+ thorax injury and had longer ICU stays. Osteopenic individuals were more likely to sustain upper extremity injuries and fractures, and were less likely to be discharged to a rehabilitation facility. Osteosarcopenic individuals were less likely to be ventilated or admitted to the ICU but tended to spend more time on the ventilator if placed on one. Conclusions: Osteosarcopenia was not associated with any injury outcomes, but sarcopenia was associated with thoracic injury and osteopenia was associated with upper extremity injury incidence. Sarcopenia was only associated with ICU length of stay, while osteopenia was only associated with discharge destination. Osteosarcopenia was associated with likelihood of being ventilated, being admitted to the ICU, and with increased length of ventilation.

Injury patterns in motor vehicle collision-pediatric pedestrian deaths

Objective To describe fatal pediatric pedestrian injury patterns and correlate them with motor vehicle collision (MVC) characteristics and pedestrian kinematics using data from medicolegal death investigations of MVCs occurring in the current Canadian MV fleet and determine the applicability of the classical “Waddell’s triad” comprising knee, hip (femur) or pelvis and craniocerebral injuries to present data injury patterns. Methods An Injury Data Collection Form was used to extract MV, MVC, pedestrian demographic and injury information from the Office of the Chief Coroner for Ontario database using autopsy data from 2013 to 2018. Injuries were coded using the Abbreviated Injury Scale (AIS) 2015 revision. The study focused on AIS ≥3 injuries utilizing the Maximum Abbreviated Injury Scale (MAIS), MAIS by Body Region (MAISBR) and Injury Severity Score (ISS). Results Between 2013 and 2018, there were 25 pediatric deaths. The pedestrians were either struck and run over (n = 17, 68%; 56% low speed) or struck and projected (n = 8, 32%). Twenty-two deaths were from frontal impacts; three were from reversing vehicles. Fourteen of the 17 (82.4%) run over cases occurred at low speed (<30 km/h). In 9 (36%) cases, the vehicle was turning at impact (right n = 3, left n = 6). A majority of the vehicles had a high hood edge. The head was the most severely injured (median MAISBR = 5 overall and ≤10 years; median MAISBR = 6 for 11–14 years old) followed by the neck (MAISBR = 3 overall; 6–14 years old), and the thorax (median MAISBR = 3 overall; all age groups). For the early adolescents (11-14 years old), the serious injury pattern included the abdomen (median MAISBR = 3.5). Nearly half (n = 11, 44%) sustained brainstem injuries. Over fifty percent of the 16 cases with neck injuries (n = 9, 56.3%) had atlanto-occipital or axial dislocation. Conclusion More than half of the deaths occurred during low speed run overs. MAIS ≥3 injuries trended to a dyad of head and thorax in ≤5 years old, a triad of head, neck, and thorax injuries in children 6–10 years old and a tetrad with the addition of abdominal injuries in pedestrians ≥11 years old. Waddell’s triad was not applicable to the fatal cases in the present study.

Characterizing future crashes on Indian roads using counterfactual simulations of pre-crash vehicle safety technologies

India's national road crash statistics indicate a continuing increase in casualties. Pre-crash safety technologies are effective in high-income countries, but it is unclear how these will perform in India and which crash types will remain after their implementation. The study objective was to predict and characterize the crashes resulting in moderate or more-severe injuries (Maximum Abbreviated Injury Scale 2 or above: MAIS2+) that remain on Indian roads after 22 pre-crash safety technologies have been implemented in all cars, heavy vehicles (buses and trucks), and Powered Two-Wheelers (PTW). Two deterministic rulesets (one optimistic and one conservative) were modeled for each of the pre-crash safety technologies. Each rule was designed and tuned to the functionality of one technology. The data were obtained from the Road Accident Sampling System India (RASSI) database. In addition to the effectiveness of each technology alone, the combined effectiveness of all technologies was estimated. Further, the characteristics of those crashes that none of the technologies would have avoided were determined. Rear-end-specific Autonomous Emergency Braking (AEB REAR-END) and Electronic Stability Control (ESC) installed in cars and heavy vehicles reduced MAIS2+ crashes the most. Crashes between PTWs and cars were significantly reduced by a rear-end-specific AEB installed in the cars. A pedestrian-specific AEB (AEB-PED) in cars and heavy vehicles was also shown to be effective. The only pre-crash safety technology in PTWs that was included, Antilock Braking Systems (ABS), reduced overall PTW crash involvement, but only reduced PTW-to-pedestrian crashes marginally. The largest proportion of remaining crashes were those that involved PTWs, indicating that PTW safety will remain a concern in future.

Factors influencing injury severity to belted drivers in car crashes in India

Objective The 2019 revised Indian seat belt regulation resulted in a significant increase in driver belt use. This study examines the factors influencing Maximum Abbreviated Injury Scale (MAIS) 2+ injuries to belted car drivers using Indian crash data. Methods Crash data obtained from Road Accident Sampling System–India (RASSI; 2011 to 2020) were used. Analysis was performed on a sample of 662 belted car drivers, representing 1.7 million drivers nationally. Survey logistic regression was used to identify factors influencing the odds of MAIS 2+ injuries to belted car drivers. Factors including delta-V, mass ratio (striking vehicle/struck vehicle), crash type, and driver age and gender were examined. The model fits and the statistical significance of each factor included in the models were examined. In addition, clinical review of crashes with belted drivers sustaining MAIS 3+ injury is presented. Results Delta-V was the most significant factor (odds ratio = 12%; 95% confidence interval 6%–19%) influencing belted driver injuries. Older drivers (55+ years) have a higher odds of MAIS 2+ injury. By adding mass ratio to the model, the odds ratio for delta-V increased to 1.16. If the mass ratio is 2.5 (striking vehicle weight = 2.5 times struck vehicle weight), then the odds of MAIS 2+ injury for the struck vehicle driver doubles. The average Delta-V for MAIS 2+ crashes is 34 mph and injury risk increases significantly when delta-V approaches 30 mph. Seventy percent of crashes with injured drivers had a mass ratio >2. For drivers with minor/no injuries, 88% of crashes had a mass ratio <2. Review of MAIS 3+ injury crashes showed that these crashes had a high delta-V (38 mph) and high mass ratio (5). Sixty percent of belted drivers sustained MAIS 3+ head or chest injury resulting from reduction in survival space. About 37% of AIS 3+ head injuries were subdural hemorrhages and 20% were crush injury to head. AIS 3+ chest injuries were rib fractures (40%) and lung lacerations/ruptures (27%). Conclusion Delta-V and mass ratio are significant factors of belted driver injuries in India. Serious injuries are mainly to the head and chest. Increased rear underrun protection device (RUPD) fitment rate, improved airbag and RUPD design, safe speed enforcement, and improved road infrastructure will reduce injury severity.

Maxillofacial Fractures in Electric and Conventional Bicycle-Related Accidents

With the increased use of both e-bike and conventional bicycle, the number of bicycle-related accidents has increased accordingly. To determine whether there are differences in maxillofacial injuries between these 2 types of bicycle accidents, e-bike and conventional bicycle accidents were compared. A retrospective cohort study was conducted for all the consecutive patients with maxillofacial injury due to e-bike and conventional bicycle accidents attending the emergency department of 4 hospitals in the Netherlands between May 2018 and October 2019. Primary outcomes are maxillofacial fractures present or absent and the severity of maxillofacial injury using the Maximum Abbreviated Injury Scale and Facial Injury Severity Scale (FISS) after e-bike and conventional bicycle accidents. A binary logistic regression analysis was used to assess differences in risk between an e-bike and conventional bicycle accident, where age, alcohol use, and comorbidities were added as covariates, for maxillofacial fractures, dental injury, and severe maxillofacial fractures. In total, 311 patients were included (73 e-bikers and 238 conventional cyclists). Sex distribution was equal in both groups (45% male vs 55% female). The e-bike group was older (66 vs 53 median age in years, P<.001) and had more comorbidities (0 vs 1, P<.001), while alcohol use was higher in the conventional bicycle group (32% vs 16%, P=.008). e-Bikers sustained midfacial fractures more frequently (47% vs 34%, P=.04), whereas conventional cyclists more often had mandibular fractures (1% vs 11%, P=.01). Although median Maximum Abbreviated Injury Scale and FISS scores did not differ between e-bike and conventional bicycle accidents, severe maxillofacial fractures (FISS score ≥ 2) were observed more often in the conventional cyclists (45% vs 25%, P=.04). No significant differences in risk of midfacial, mandibular, and severe maxillofacial fractures were found between e-bikers and conventional cyclists irrespective of their age, alcohol use, and comorbidities. Both the distribution and the severe maxillofacial fractures differed between the e-bike and conventional bicycle accident patients. Patient-specific characteristics, such as age, alcohol use, and comorbidities, may have a greater influence on sustaining maxillofacial fractures than the type of bicycle ridden.

How many are enough?: Investigating the effectiveness of multiple conflict indicators for crash frequency-by-severity estimation by automated traffic conflict analysis

Traffic conflict techniques are a viable alternative to crash-based safety assessments and are particularly well suited to evaluating emerging technologies such as connected and automated vehicles for which crash data are sparsely available. Recently, the use of multiple traffic conflict indicators has become common in methodological studies, yet it is often difficult to determine which conflict indicators are appropriate given the application context, and the net benefit, in terms of improved crash prediction accuracy, of considering additional conflict indicators. Addressing these concerns, this study investigates the potential benefits of multiple conflict indicators for conflict-based crash estimation models by using a multivariate extreme value modeling framework (with Gumbel-Hougaard copulas) to estimate crash frequency by severity. The selected conflict indicators include Modified Time-To-Collision (MTTC), Deceleration Rate to Avoid a Collision (DRAC), Proportion of Stopping Distance (PSD) and expected post-collision change in velocity (Delta-V). The proposed framework was applied to estimate the total, severe (Maximum Abbreviated Injury Scale ≥ 3; MAIS3+), and non-severe (MAIS < 3) rear-end crash frequencies at three four-legged signalized intersections in Brisbane, Australia. Rear-end traffic conflicts were extracted from video data using state-of-the-art Computer Vision analytics. Results show that the prediction performance improvements are not necessarily proportional to the number of conflict indicators used in extreme value models. MTTC and DRAC, combined with the severity indicator Delta-V, were the most suitable predictors of rear-end crashes at signalized intersections. Results suggest that instead of adding more and more conflict indicators, careful selection of compatible conflict indicators (considering their functional differences and empirical correlations) is the best way to enhance the predictive performance of conflict-based models.

Adult occupant injury risk in rear impact and frontal impact: Effect of impact conditions and occupant-related factors

Objectives The objectives of this study were to compare the adult occupant injury risk on specific body regions in frontal and rear impact and to investigate the effect of those crash conditions and occupant-related factors on the injury risk. Method Data from the NASS-CDS and Crash Investigation Sampling System were studied for crashes during 2000 to 2019 involving model year 2000 to 2020 motor vehicles, including frontal collisions and rear-end collisions. The injury risk by specific body regions were compared by descriptive statistics, and logistic regression models were developed to examine the effects of various factors on injury risk by specific body regions, controlling for crash type (frontal impact and rear impact), vehicle impact speed, vehicle impact location, vehicle model year, and occupant gender, age, belt use, and seating position. Results After controlling for the confounding factors, the occupants in frontal impact had higher overall injury risk than in rear impact (at Maximum Abbreviated Injury Scale [MAIS] 3+; odds ratio [OR] = 6.23; 95% confidence interval [CI] [6.06–6.40]), except for lower neck/spine injury risk at MAIS 1+ (OR = 0.47; 95% CI [0.46–0.47]). The impact speed (at MAIS 3+; OR = 1.10; 95% CI [1.10–1.10]) and aging (at MAIS 3+; OR = 1.05; 95% CI [1.05–1.05]) increase overall injury risk, and the unbelted occupants had higher overall injury risk than belted occupants not only in frontal impact (at MAIS 3+; OR = 4.04; 95% CI [3.98–4.10]), but also in rear impact (at MAIS 3+; OR = 28.4; 95% CI [26.4–30.5]). Females had higher overall injury risk than males in frontal impact (at MAIS 3+; OR = 2.01; 95% CI [1.99–2.04]) but not in rear impact (at MAIS 3+; OR = 0.77; 95% CI [0.73–0.81]). Conclusions Occupants in rear impact had lower injury risk than in frontal impact at MAIS 1+ to MAIS 3+, except for neck/spine at MAIS 1+. The belt restraint was effective not only in frontal impact but also in rear impact. This study provided injury risk references for current vehicles that may provide insight to the potential injury risk of rear-facing occupants in future vehicle configurations.

A Case Report on a Patient Whose Road Traffic Injury Severity Was Determined by the MAIS (Maximum Abbreviated Injury Scale) Score

Abstract There are numerous definitions and classifications of severe trauma. Due to the observed heterogeneity in the existing definitions and the lack of a uniform definition of serious bodily injury, in January 2013 the High Level Group on Road Safety EU (HLGRS) published the definition of serious bodily injury in road traffic as a non-fatal injury with Maximum Abbreviated Injury Scale (MAIS) between 3 and 6, including the limit values. However, determining the MAIS score is not easy even for doctors with many years of experience. A female patient, injured as a pedestrian in a traffic accident, was examined prehospitally, and was transported to the hospital in the optimal golden hour from the time of the injury. The patient was intubated and mechanically ventilated in the Critical Care Resuscitation Unit. After the entire diagnostic procedure, diagnoses were made according to the ICD classification of diseases. During further examination, each code of the diagnosis of the disease was assigned an AIS code and the highest AIS score - AIS 5 was determined, which indicated that the patient was critically injured. Our patient's MAIS score was 5. After 39 days she was discharged from hospital. The neurological findings at discharge corresponded to left hemiparesis – ASIA D impairment grade. In conclusion, a novelty in the assessment of severe bodily injury is the introduction of the AIS/MAIS score. However, to avoid a subjective assessment of these scores, AIS dictionaries should be obtained for physicians, or a software solution should be developed to convert ICD-10 diagnoses into the AIS / MAIS injury scale.

Clinical and Physiologic Factors Associated With Mode of Death in Pediatric Severe TBI.

Aims and Objectives: Severe traumatic brain injury (sTBI) is the leading cause of death in children. Our aim was to determine the mode of death for children who died with sTBI in a Pediatric Critical Care Unit (PCCU) and evaluate factors associated with mortality.Methods: We performed a retrospective cohort study of all severely injured trauma patients (Injury Severity Score ≥ 12) with sTBI (Glasgow Coma Scale [GCS] ≤ 8 and Maximum Abbreviated Injury Scale ≥ 4) admitted to a Canadian PCCU (2000–2016). We analyzed mode of death, clinical factors, interventions, lab values within 24 h of admission (early) and pre-death (48 h prior to death), and reviewed meeting notes in patients who died in the PCCU.Results: Of 195 included patients with sTBI, 55 (28%) died in the PCCU. Of these, 31 (56%) had a physiologic death (neurologic determination of death or cardiac arrest), while 24 (44%) had withdrawal of life-sustaining therapies (WLST). Median (IQR) times to death were 35.2 (11.8, 86.4) hours in the physiologic group and 79.5 (17.6, 231.3) hours in the WLST group (p = 0.08). The physiologic group had higher partial thromboplastin time (PTT) within 24 h of admission (p = 0.04) and lower albumin prior to death (p = 0.04).Conclusions: Almost half of sTBI deaths in the PCCU were by WLST. There was a trend toward a longer time to death in these patients. We found few early and late (pre-death) factors associated with mode of death, namely higher PTT and lower albumin.

Travel speed and the risk of serious injury in vehicle crashes

While there is a large quantity of prior research on speed and road safety, no previous studies have quantified the absolute risk of serious injury in a crash relative to travel speed. This study aimed to produce risk curves that relate travel speed to the risk of serious injury in light vehicle impacts in order to contribute to the process of selecting acceptable travel speeds. Serious injury was defined in this study as any injury having a maximum abbreviated injury scale (MAIS) of three or greater, or a fatal injury (MAIS3+F). In the context of a crash, travel speed is defined as the vehicle's speed before the driver reacts to the crash situation. Travel speed was determined by selecting the highest pre-impact speed recorded by an Event Data Recorder (EDR) in the seconds before the crash. A total of 1,618 light vehicle impacts were analysed using logistic regression. Individual risk curves were produced for front, head on, side, rear and single vehicle impacts. The analysis found significant positive relationships between the risk of serious injury and travel speed for all of these impact types. The travel speeds at which the risk of serious injury reached one per cent were 63 km/h across all impacts, 17 km/h for head on impacts, 48 km/h for single vehicle impacts, 58 km/h for side impacts, 81 km/h for front impacts and 96 km/h for rear impacts. These results have implications for the setting of speed limits and other measures that influence the speed at which vehicles travel.