Renal injury in a child with airbag deployment

Incidence and mechanism of neurological deficit after thoracolumbar fractures sustained in motor vehicle collisions

OBJECT To determine the incidence of and assess the risk factors associated with neurological injury in motor vehicle occupants who sustain fractures of the thoracolumbar spine. METHODS In this study, the authors queried medical, vehicle, and crash data elements from the Crash Injury Research and Engineering Network (CIREN), a prospectively gathered multicenter database compiled from Level I trauma centers. Subjects had fractures involving the T1-L5 vertebral segments, an Abbreviated Injury Scale (AIS) score of ≥ 3, or injury to 2 body regions with an AIS score of ≥ 2 in each region. Demographic parameters obtained for all subjects included age, sex, height, body weight, and body mass index. Clinical parameters obtained included the level of the injured vertebra and the level and type of spinal cord injury. Vehicular crash data included vehicle make, seatbelt type, and usage and appropriate use of the seatbelt. Crash data parameters included the principal direction of force, change in velocity on impact (ΔV), airbag deployment, and vehicle rollover. The authors performed a univariate analysis of the incidence and the odds of sustaining spinal neurological injury associated with major thoracolumbar fractures with respect to the demographic, clinical, and crash parameters. RESULTS Neurological deficit associated with thoracolumbar fracture was most frequent at extremes of age; the highest rates were in the 0- to 10-year (26.7% [4 of 15]) and 70- to 80-year (18.4% [7 of 38]) age groups. Underweight occupants (OR 3.52 [CI 1.055-11.7]) and obese occupants (OR 3.27 [CI 1.28-8.31]) both had higher odds of sustaining spinal cord injury than occupants with a normal body mass index. The highest risk of neurological injury existed in crashes in which airbags deployed and the occupant was not restrained by a seatbelt (OR 2.35 [CI 0.087-1.62]). Reduction in the risk of neurological injuries occurred when 3-point seatbelts were used correctly in conjunction with the deployment of airbags (OR 0.34 [CI 1.3-6.6]) compared with the occupants who were not restrained by a seatbelt and for whom airbags were not deployed. Crashes with a ΔV greater than 50 km/hour had a significantly higher risk of spinal cord injury (OR 3.45 [CI 0.136-0.617]) than those at lower ΔV values. CONCLUSIONS Deployment of airbags was protective against neurological injury only when used in conjunction with 3-point seatbelts. Vehicle occupants who were either obese or underweight, very young or elderly, and those in crashes with a ΔV greater than 50 km/hour were at higher risk of thoracolumbar neurological injury. Neurological injury at thoracic and lumbar levels was associated with multiple factors, including the incidence of fatality, occupant factors such as age and body habitus, energy at impact, and direction of impact. Current vehicle safety technologies are geared toward a normative body morphology and need to be reevaluated for various body morphologies and torso compliances to lower the risk of neurological injury resulting from thoracolumbar fractures.

The impact of seat belts and airbags on high grade renal injuries and nephrectomy rate in motor vehicle collisions

PURPOSE

Motor vehicle collisions are the most common cause of blunt genitourinary trauma. We compared renal injuries with no protective device to those with seat belts and/or airbags using NTDB. Our primary end point was a decrease in high grade (grades III-V) renal injuries with a secondary end point of a nephrectomy rate reduction.

MATERIALS AND METHODS

The NTDB research data sets for hospital admission years 2010, 2011 and 2012 were queried for motor vehicle collision occupants with renal injury. Subjects were stratified by protective device and airbag deployment. The AIS was converted to AAST renal injury grade and nephrectomy rates were evaluated. Intergroup comparisons were analyzed for renal injury grades, nephrectomy, length of stay and mortality using the chi-square test or 1-way ANOVA. The relative risk reduction of protective devices was determined.

RESULTS

A review of 466,028 motor vehicle collisions revealed a total of 3,846 renal injuries. Injured occupants without a protective device had a higher rate of high grade renal injuries (45.1%) than those with seat belts (39.9%, p = 0.008), airbags (42.3%, p = 0.317) and seat belts plus airbags (34.7%, p <0.001). Seat belts (20.0%), airbags (10.5%) and seat belts plus airbags (13.3%, each p <0.001) decreased the nephrectomy rate compared to no protective device (56.2%). The combination of seatbelts and airbags also decreased total hospital length of stay (p <0.001) and intensive care unit days (p = 0.005). The relative risk reductions of high grade renal injuries (23.1%) and nephrectomy (39.9%) were highest for combined protective devices.

CONCLUSIONS

Occupants of motor vehicle collisions with protective devices show decreased rates of high grade renal injury and nephrectomy. Reduction appears most pronounced with the combination of seat belts and airbags.

Injuries caused by airbags: a review

With the number of vehicles on the road increasing, the safety aspects of motoring are becoming a progressively more important consideration in health care provision and policy. Airbags are a relatively new introduction into our vehicles. Unlike other mechanisms such as seat belts, they offer protection without the need for any action on the part of the occupant. However, the necessarily violent nature of their deployment has led to the emergence of patterns of injury as a direct result. Knowledge of the potential dangers posed by these systems is useful both for emergency department physicians in order to prevent important injuries being missed, and for car manufacturers using increas ingly modern technology to design more efficient mechanisms. We undertook a review of the current literature to ascertain the spectrum of injuries that have been attributed to the use of airbags, while putting this into the wider context of their protective contribution.

Air bag injuries--a literature review in consideration of demands in forensic autopsies

Air bags have been implicated in saving lives and reducing morbidity associated with motor vehicle crashes since their introduction in the mid-1970s. However, there is increasing evidence showing that air bags can be a source of injury and even death in certain circumstances. As the number of air bag-equipped vehicles increases, air bag-related injuries have occurred more frequently. Thus, a greater awareness of air bag-related injuries is required in forensic autopsies. Here, we review thoroughly the literature concerning air bag-related injuries with special regard to their nature and causative mechanisms, and summarize air bag-related injuries observed in adults, children and infants.