Factors influencing pediatric Injury Severity Score and Glasgow Coma Scale in pediatric automobile crashes: results from the Crash Injury Research Engineering Network

Background/Purpose

Motor vehicle crashes account for more than 50% of pediatric injuries. Triage of pediatric patients to appropriate centers can be based on the crash/injury characteristics. Pediatric motor vehicle crash/injury characteristics can be determined from an in vitro laboratory using child crash dummies. However, to date, no detailed data with respect to outcomes and crash mechanism have been presented with a pediatric in vivo model.

Methods

The Crash Injury Research Engineering Network is comprised of 10 level 1 trauma centers. Crashes were examined with regard to age, crash severity (ΔV), crash direction, restraint use, and airbag deployment. Multiple logistic regression analysis was performed with Injury Severity Score (ISS) and Glasgow Coma Scale (GCS) as outcomes. Standard age groupings (0-4, 5-9, 10-14, and 15-18) were used. The database is biases toward a survivor population with few fatalities.

Results

Four hundred sixty-one motor vehicle crashes with 2500 injuries were analyzed (242 boys, 219 girls). Irrespective of age, ΔV > 30 mph resulted in increased ISS and decreased GCS (eg, for 0-4 years, ΔV < 30: ISS = 10, GCS = 13.5 vs ΔV > 30: ISS = 19.5, GCS = 10.6; P < .007, < .002, respectively). Controlling for ΔV, children in lateral crashes had increased ISS and decreased GCS versus those in frontal crashes. Airbag deployment was protective for children 15 to 18 years old and resulted in a lower ISS and higher GCS (odds ratio, 2.1; 95% confidence interval, 0.9-4.6). Front-seat passengers suffered more severe (ISS > 15) injuries than did backseat passengers (odds ratio, 1.7; 95% confidence interval, 0.7-3.4). A trend was noted for children younger than 12 years sitting in the front seat to have increased ISS and decreased GCS with airbag deployment but was limited by case number.

Conclusion

A reproducible pattern of increased ISS and lower GCS characterized by high severity, lateral crashes in children was noted. Further analysis of the specific injuries as a function and the crash characteristic can help guide management and prevention strategies.     

Blood transfusion in critically injured patients: a prospective study

BACKGROUND: Despite evolving evidence that transfusion risks outweigh benefits in some patients, the critically injured continue to receive large quantities of blood. The present study evaluated patterns of red blood cell transfusions and risk factors for transfusions at various stages of admission in trauma patients. STUDY DESIGN: Prospective, observational study of transfusion practices in patients (n = 120) admitted to a single Level 1 academic trauma centre. Patients were expected to remain in the surgical intensive care unit for greater than 48 h. RESULTS: Patients had a mean age of 34.1+/- 16.0 years, a mean injury severity score (ISS) of 21.5 +/- 9.5, and were equally distributed by major injury type (48% blunt, 52% penetrating). One hundred and four patients (87%) received a total of 324 transfusions, 20 (6%) of which were given in the emergency room, 186 (57%) in the SICU, 22 (7%) post-SICU and 96 (30%) in the operating room. The mean volume of blood per patient transfused was 3144 +/- 2622 mL. One hundred and one patients received an allogeneic transfusion (mean volume 3126 +/- 2639 mL) and 10 patients received an autotransfusion (844 +/- 382 mL). The mean pre-transfusion Hb level was 9.1 +/- 1.4 g/dL. Transfusion volumes correlated with injury severity score (p = 0.011). Patients with an admission Hb < or =12 g/dL or age >55 years were at significant risk to receive increased transfusions (P < .001 and P = .035, respectively). An admission Hb < or =12 g/dL and any mention of long bone orthopedic operations or laparotomy or thoracotomy were associated with increased risk of blood transfusion during the first week of admission. Logistic regression analysis identified transfusion of >4 units of blood as a significant risk factor for SIRS. After 1 week of ICU stay, ISS > 20 and blunt injury were associated with increased risk of transfusion. CONCLUSIONS: Trauma patients are heavily transfused with allogeneic blood throughout the course of their hospital stay and transfusions are administered at relatively high pre-transfusion haemoglobin levels (mean of 9 g/dL). Transfusion of >4 units of blood is an independent risk factor for SIRS. Strategies to limit blood transfusions should be investigated in this population.     

A single surgeon's experience of treatment of Lisfranc joint injuries

This paper assesses the outcomes and complications of Lisfranc joint injuries treated at a regional trauma centre under the care of a single surgeon. We performed a retrospective study of all patients that underwent ORIF of a Lisfranc joint injury over a 5-year period. Case note review, radiology review, and questionnaire assessment were performed. We analysed for correlations between outcome and injury type, mechanism of injury, and presence of other ipsilateral limb injury and pure ligamentous injury. All injuries were classified according to a system described by Myerson et al. (Types A, B1, B2, C1, C2). Radiographs were also assessed for the presence of pure ligamentous injury. Outcome was measured using the American Orthopaedic Foot and Ankle society (AOFAS) midfoot score. Twenty-five injuries (24 patients) were identified and 16 injuries (15 patients) were available for follow. The mean duration of follow up was 42.6 months (11-69). The mean outcome score was 78.3 (38-100). The outcome scores for pure ligamentous injury (74.9) and for mixed bony and ligamentous injury (80.9) had no significant difference (p=0.61). High-energy trauma accounted for 50% of cases, and scored significantly less than low energy trauma (69.1 versus 87.4, p<0.05). There was an associated injury in the ipsilateral limb in 31% of cases and this group had a poorer outcome (63.0 versus 85.3, p<0.035). The most common injury type was B2 (38%). Type C2 injuries (divergent with total displacement) had a worse outcome than the mean outcome of all other categories (60.5 versus 84.4, p<0.01). Our mean outcome from ORIF of Lisfranc joint injuries is comparable to internationally quoted figures. Pure ligamentous injuries did no worse statistically than mixed bony and ligamentous injuries. Poorer outcome was associated with high-energy trauma, associated injury on the ipsilateral limb, and Type C2 injuries.     

Demographic, social and economic variables that affect lower extremity injury outcomes

While behavioral, demographic and vocational factors are commonly know as risk factors for sustaining a traumatic injury, less is known about the social, demographic and economic determinants of outcome following injury. The Lower Extremity Assessment Project (LEAP) identified a prospective cohort of 601 patients who were admitted to eight level I trauma centers in the United States for treatment of severe lower extremity trauma. Prospective data was accumulated on these individuals throughout their initial hospitalization and at regular follow-up intervals including a cohort at seven years post-injury. The results of the LEAP investigations showed that even at five to seven years following injury, reconstruction for the treatment of injuries to the lower extremity typically result in functional outcomes equivalent to those of the amputation. Clearly, factors other than the traditional variables such as fracture healing, joint function, and ability to ambulate have a profound effect on the patient's estimation of improvement. The purpose of this report is to summarize the data from the LEAP study and other investigations related to demographic, social and behavioral factors which impact outcome following lower extremity injury.     

The use of factor VIIa in haemorrhagic shock and intracerebral bleeding

Factor VIIa is a revolutionary new pharmaceutical that promises to change the anaesthesia and critical care approach to major trauma. It is an extremely potent pro-coagulant agent, and while it enables haemostasis at the site of tissue injury, it also has the possibility of producing life-threatening thromboembolic complications. New data regarding FVIIa use is published almost every month, leading to a rapidly evolving clinical understanding of the potential indications, and potential pitfalls, of off-label use. Determination of appropriate practice, including the ability to judge the risks and benefits of FVIIa therapy for individual cases, is still some years in the future, and will depend in large part on clinical trials which are just getting underway.     

Assessment of the pregnant trauma patient

Although less than 10% of pregnant patients are likely to experience some type of physical trauma, injury is the leading non-obstetric cause of maternal mortality. The assessment and resuscitation of the injured pregnant patient must take into account the specific needs of both the mother and the foetus. This paper will review the physiology of pregnancy, discuss recent changes in assessment and resuscitation, and identify special injuries and issues specific to the pregnant trauma patient.     

Magnetic resonance imaging of articular cartilage: ex vivo study on normal cartilage correlated with magnetic resonance microscopy

The aims of this study were (a) to compare the MR appearance of normal articular cartilage in ex vivo MR imaging (MRI) and MR microscopy (MRM) images of disarticulated human femoral heads, (b) to evaluate by MRM the topographic variations in articular cartilage of disarticulated human femoral heads, and subsequently, (c) to compare MRM images with histology. Ten disarticulated femoral heads were examined. Magnetic resonance images were obtained using spin-echo (SE) and gradient-echo (GE) sequences. Microimages were acquired on cartilage–bone cylindrical plugs excised from four regions (superior, inferior, anterior, posterior) of one femoral head, using a modified SE sequence. Both MRI and MRM images were obtained before and after a 90 ° rotation of the specimen, around the axis perpendicular to the examined cartilage surface. Finally, MRM images were correlated with histology. A trilaminar appearance of articular cartilage was observed with MRI and with a greater detail with MRM. A good correlation between MRI and MRM features was demonstrated. Both MRI and MRM showed a loss of the trilaminar cartilage appearance after specimen rotation, with greater evidence on MRM images. Cartilage excised from the four regions of the femoral head showed a different thickness, being thickest in the samples excised from the superior site. The MRM technique confirms the trilaminar MRI appearance of human articular cartilage, showing good correlation with histology. The loss of the trilaminar appearance of articular cartilage induced by specimen rotation suggests that this feature is partially related to the collagen-fiber orientation within the different layers. The MRM technique also shows topographic variations in thickness of human articular cartilage. Received 28 July 1997; Revision received 31 December 1997; Accepted 6 January 1998     

Platelet-activating factor (PAF) involvement in acetaminophen-induced liver toxicity and regeneration

Acetaminophen-induced toxicity has been attributed to cytochrome P-450-generated metabolites, which covalently modify target proteins. However, the mechanism of liver injury pathogenesis needs to be further elucidated. Platelet-activating factor (PAF) is one of the mediators involved in inflammatory tissue alterations associated with acute liver failure. In this study, alterations in blood PAF levels and the serum activity of PAF-acetylhydrolase (PAF-AH) were investigated over the time course of liver injury and regeneration induced by acetaminophen treatment in rats. The administration of a toxic dose of acetaminophen (3.5 g/kg) in rats caused acute hepatic injury, as evident by alterations of biochemical (serum enzymes: ALT, AST and ALP) and liver histopathological (degree of inflammation and apoptosis) indices between 20 and 40 h post-treatment. The hepatic damage was followed by liver regeneration, made evident by three independent indices ([3H]thymidine incorporation into hepatic DNA, liver thymidine kinase activity and hepatocyte mitotic index), presenting a peak at 72 h. The PAF levels were elevated at 24 and 28 h, presenting a remarkable peak at 32 h post-treatment. PAF-AH activity presented different kinetics to that of PAF. The enzyme activity was relatively low at all time points examined before the rise in PAF activity, peaking later, at 72, 84 and 96 h. Our data demonstrate that PAF is involved in the pathogenesis of acute liver failure and in augmented compensatory liver tissue repair post-acetaminophen treatment. However, the putative role of PAF during liver toxicity and regeneration remains to be established.     

Preventing choking and suffocation in children

Choking, suffocation and strangulation cause serious unintentional injuries in children and are leading causes of unintentional death in infants and toddlers. Nearly all choking, suffocation and strangulation deaths and injuries are preventable. The present statement reviews definitions, epidemiology and effective prevention strategies for these injuries. Recommendations that combine approaches for improving safety, including research, surveillance, legislation and standards, product design and education, are made. Paediatric health care providers should be encouraging parents and other caregivers to learn cardiopulmonary resuscitation (CPR) and choking first aid, as well as offering anticipatory, age-appropriate guidance to prevent these injuries at regular health visits.     

第95百分位中国人头部颅脑相对位移的有限元评估

目的构建第95百分位中国人头部有限元模型,分别参照4种不同类型的颅脑相对位移试验对其进行有效性验证,并评估颅骨与脑组织之间的相对位移,同时探讨脑组织的剪应变分布。方法比较试验与仿真中的颅脑相对位移曲线,并结合动物试验和物理试验中所得出的结论,探讨较高剪应变出现的位置。结果仿真所得的颅脑相对位移曲线与试验结果基本吻合,由于脑组织总是恢复到初始状态,曲线总是出现波峰和波谷。较高剪应变出现在大脑颞叶、胼胝体和脑表面的位置,与动物试验和物理试验中所得出的结论较为相符。结论第95百分位中国人头部有限元模型具有良好的生物仿真度。由于头部的旋转运动,脑表面和脑组织深处都会出现较高的剪应变,从而导致损伤,故本文的研究结果为开展在交通事故中头部损伤机理的研究提供了科学的理论依据。