Dissertations / Theses on the topic 'Mechanical trauma'

Orientador: Felippe Bevilacqua Prado
Texto em português e inglês
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo deste estudo foi analisar a distribuição de tensões de cargas aplicadas em sínfise de mandíbula desdentada humana de idoso por meios de análise fotoelástica e de elementos finitos. Foram analisadas correlações entre as cargas aplicadas e as tensões registradas. Os testes de carga em resina fotoelástica foram realizados em uma máquina acoplada a um polariscópio e uma câmera digital. Cargas perpendiculares foram aplicadas em sínfise. Cargas variaram de 50 a 723 Newtons. Uma tomografia computadorizada foi realizada para gerar um modelo digital da mandíbula macerada. Os modelos computadorizados para a análise de elementos finitos (AEF) foram caracterizados de acordo com as propriedades mecânicas da resina epóxi e do osso. As áreas 1, 2, 3 e 4 exibiram franjas isocromáticas de ordem 2 em cargas 150 a 300N, e franjas de ordem 3 em cargas de 350 a 700N. Os stresses de vonMises se distribuíram similarmente em ambos os modelos caracterizados como resina epóxi e osso.Houve uma excelente (rP> 0.9) e significante (p < 0.05) correlação entre as cargas aplicadas e as respostas obtidas em todas as áreas apesar de algumas delas como as 9 e 10 no corpo mandibular que demonstraram correlações muito boa (rP> 0.7) e significante (p <0.05) respectivamente
Abstract: The aim of this study was to analyze the distribution of stresses from loads applied on symphysis in human elderly edentulous mandible by photoelastic analysis and FEA. Correlations between the applied load and stress tension at each evaluated area were evaluated. Load tests on the photoelastic resin model of edentulous macerated hemimandible were performed in a testing machine equipped with polariscope and a digital camera. Perpendicular loads were applied on symphysis area.Loads ranged from 50 to 723 N. CT was performed on the same mandible used to generate the photoelastic resin model. Computational models to the FEA were characterized according to the mechanical properties of epoxy resin and bone. 1, 2, 3 and 4 areas showed fringes order 2 in loads of 150 to 300N, and fringes order 3 in loads of 350 to 700N. von Mises stress were distributed similarly in both characterized models, epoxy resin and bone. There was an excellent (rP> 0.9) and significant (p < 0.05) correlation between the loads applied and the responses obtained in all areas, regardless of the area considered but areas 9 and 10 for the mandibular body, which showed very good (rP> 0.7) and significant (p <0.05)correlation
Doutorado
Anatomia
Doutor em Biologia Buco-Dental

Figueroa-Ramosa et al. (2013) concluded that the combination of sedation withdrawal and mechanical ventilation withdrawal trial was feasible and well tolerated. The conclusion is not well supported because of the absence of a comparison to the uncombined protocol and due to evidence that the patients did not tolerate them particularly well.

College student and Amazon's Mechanical TURK (MTURK) samples are regularly utilized in trauma research. Recent literature, however, has criticized these samples for not being generalizable to the general U.S. population. Measurement invariance (MI) using confirmatory factor analyses (CFA), is rarely utilized in trauma research, even though the analysis can determine whether groups are invariant across factor structure, factor loadings, item intercepts, and residual error variances on a given measure of PTSD symptom severity. The purpose of this study was to determine whether college student (n = 255) and MTURK (n = 316) samples are invariant on the PCL-5. Model fit indices indicated the 7-factor Hybrid model was the best fitting model, but the 6-factor anhedonia model was the most parsimonious model. Both models demonstrated equivalence in factor structures (configural invariance), factor loadings (metric invariance), intercepts (scalar invariance), and residuals (strict invariance), indicating MTURK and college student samples are similar in regards to PTSD symptom severity. These findings provide evidence that these groups can be combined in future studies to increase sample size for trauma research. Only the Anhedonia factor exhibited mean differences between groups, which may be related to true differences between college students and MTURK survey-takers. Thus, there is further evidence that the findings from trauma studies using these populations are generalizable to each other.

Occupant thoracic injury incurred during side impact automotive crashes constitutes a significant portion of all fatal and non-fatal automotive injuries. The limited space between the impacting vehicle and occupant can result in significant loads and corresponding injury prior to deceleration of the impacting vehicle. Within the struck vehicle, impact occurs between the occupant and various interior components. Injury is sustained to human structural components such as the thoracic cage or shoulder, and to the internal visceral components such as the heart, lungs, or aorta. Understanding the mechanism behind these injuries is an important step in improving the side impact crash safety of vehicles. This study is focused on the development of a human body numerical model for the purpose of predicting thoracic response and trauma in side impact automotive crash.

The human body model has been created using a previously developed thoracic numerical model, originally used for predicting thoracic trauma under simple impact conditions. The original version of the thorax model incorporated three-dimensional finite element representations of the spine, ribs, heart, lungs, major blood vessels, rib cage surface muscles and upper limbs. The present study began with improvements to the original thorax model and furthered with the development of remaining body components such that the model could be assessed in side impact conditions.

The improvements to the thoracic model included improved geometry and constitutive response of the surface muscles, shoulder and costal cartilage. This detailed thoracic model was complimented with a pelvis, lower limbs, an abdomen and a head to produce the full body model. These components were implemented in a simplified fashion to provide representative response without significant computational costs. The model was developed and evaluated in a stepwise fashion using experimental data from the literature including side abdominal and pelvic pendulum impact tests.

The accuracy of the model response was investigated using experimental testing performed on post mortem human subjects (PMHS) during side and front thoracic pendulum impacts. The model produced good agreement for the side thoracic and side shoulder pendulum impact tests and reasonable correlation during the frontal thoracic pendulum impact test. Complex loading via side sled impact tests was then investigated where the body was loaded unbelted in a NHTSA-type and WSU-type side sled test system. The thorax response was excellent when considering force, compression and injury (viscous criterion) versus time. Compression in the thorax was influenced by the arm position, which when aligned with the coronal plane produced the most aggressive form of compressive loading possible. The simplified components provided good response, falling slightly outside experimental response corridors defined as one standard deviation from the average of the experimental PMHS data. Overall, the predicted model response showed reasonable agreement with the experimental data, while at the same time highlighting areas for future developments. The results from this study suggested that the numerical finite element model developed herein could be used as a powerful tool for improving side impact automotive safety.

З інтенсифікацією життєдіяльності людини збільшується ризик травматизації людини в побуті, на виробництві, що пов’язаний з урбанізацією суспільства. В зв’язку з цим збільшується кількість випадків механічного ураження шкірних покривів, яке проявляється у вигляді саден, порізів, розривів шкіри. Вони виникають внаслідок дії чинника безпосередньо на шкіру. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/35742

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Trauma is not only a serious sickness, but also a significant Public Health problem, since it is the primary pediatric mortality cause in developed countries and a determinative factor of transitory or permanent sequelae. AIMS: establish the clinical-epidemiological profile of mechanical trauma in children and adolescents, in a third Fortaleza city Count Hospital in Ceara state. METHOD: hospital based prospective observational study, proceeded with patients from zero to 19 years-old, victims of mechanical trauma, admitted by Instituto Dr. Jose Frota from February to July of 2005, being accompanied until to final moment (hospital discharge, obit or transfer). Studied variables were related to the socioeconomic and demographic conditions of patients and their families. Respect to the trauma, it was studied mechanism, type and consequences. RESULTS: 697 children were studied. Male gender was predominant (80.2%), as well as those 15 to 19 year-olds (47.8%); 53.1% came from country and 73.7% came from urban zone. Sunday was the predominant day of traumatic events (22.2%) and the afternoon time represented 37% of the cases. Mother was the primary caregiver in 69.7%. The main trauma mechanism was the drop (32.5%), followed by aggressions (25%). Skeletal trauma was the major type of trauma (60.1%), followed by traumatic brain injury (41%); 95% had light severity. Most of patients (92.1%) were discharged from hospital, 3.3% evolved to obit, 51% presented sequelae, but in 49.4% functional capacity was preserved and in 1.1% it was completely compromised.CONCLUSIONS: Trauma was more frequent among 15 to 19 year-olds and in male children and adolescents. The main trauma mechanism was the drop, being the skeletal trauma the most found. Most of cases had light severity, having motor transitory sequel as the central consequence. Most of patients were discharged from hospital and had their functional capacities preserved or simply partially compromised. Only 1.1% had invalidating or definitive sequelae
O trauma constitui-se nÃo apenas uma grave doenÃa, mas um significativo problema de SaÃde PÃblica, em virtude de ser a principal causa de mortalidade pediÃtrica nos paÃses desenvolvidos e fator determinante de sequelas transitÃrias ou permanentes.OBJETIVOS: determinar o perfil clÃnico-epidemiolÃgico do trauma mecÃnico em crianÃas e adolescentes, em um Hospital PÃblico TerciÃrio do MunicÃpio de Fortaleza no Estado do CearÃ. MÃTODO: estudo observacional, prospectivo, de base hospitalar, realizado com pacientes de zero a 19 anos vÃtimas de trauma mecÃnico, admitidos no Instituto Dr. Josà Frota no perÃodo de fevereiro a julho de 2005, sendo seguidos atà o momento do desfecho (alta hospitalar, Ãbito ou transferÃncia). Foram estudadas variÃveis relacionadas Ãs condiÃÃes socioeconÃmicas e demogrÃficas referentes ao paciente e sua famÃlia. Em relaÃÃo ao trauma estudou-se o mecanismo, o tipo e as consequÃncias. RESULTADOS: foram estudadas 697 crianÃas. Houve predominÃncia do sexo masculino (80,2%) e da faixa etÃria de 15 a 19 anos (47,8%); 53,1% foram procedentes do Interior e 73,7% da zona urbana. Domingo foi o dia em que predominaram os eventos traumÃticos (22,2%) e o turno da tarde representou 37% dos casos. A mÃe foi o cuidador primÃrio em 69,7%. A queda foi o principal mecanismo de trauma (32,5%) seguido das agressÃes (25%). O trauma esquelÃtico foi o principal tipo de trauma (60,1%) seguido de trauma cranioencefÃlico (41%); 95% tiveram gravidade leve. A maioria dos pacientes (92,1%) recebeu alta hospitalar, 3,3% evoluÃram para Ãbito, 51% apresentaram sequela, mas em 49,4% a capacidade funcional foi preservada e em 1,1% totalmente comprometida. CONCLUSÃES: trauma foi mais frequente na faixa etÃria de 15 a 19 anos e em crianÃas e adolescentes do sexo masculino. O principal mecanismo de trauma mecÃnico foi queda, sendo o trauma esquelÃtico o tipo mais encontrado. A maioria dos casos foi de gravidade leve, conduzindo a sequela motora transitÃria como principal consequencia, tendo a maioria dos pacientes recebidos alta hospitalar, com a capacidade funcional preservada ou apenas parcialmente comprometida. Apenas 1,1% tiveram sequela invalidante ou definitiva

Desenvolvemos um instrumento capaz de provocar uma lesão muscular aguda por mecanismo de impacto, no músculo gastrocnêmio de ratas, através de um trauma direto e não-invasivo. Após a produção da lesão experimental avaliamos os efeitos do ultra-som terapêutico (UST), adicionado ou não à imobilização gessada, como forma de tratamento imediato à lesão muscular pela análise das propriedades mecânicas deste músculo. Foram utilizadas 68 ratas da raça Wistar, sendo divididas em 7 grupos experimentais da seguinte forma: Grupo 1 – Controle intacto; Grupo 2 – Sem tratamento efetivo, Grupo 3 – Imobilização gessada por 24 horas; Grupo 4 – Imobilização gessada por 72 horas; Grupo 5 – Estimulação com UST sem presença de imobilização; Grupo 6 – Imobilização gessada por 24 horas associada à estimulação com UST; Grupo 7 – Imobilização gessada por 72 horas associada à estimulação com UST tratadas durante 6 dias consecutivos com UST, durante 5 minutos diários. Avaliamos as propriedades mecânicas obtidas através de ensaios mecânicos de tração longitudinal e os resultados foram analisados estatisticamente. O estudo evidenciou que a propriedade de alongamento no limite de proporcionalidade não foi um bom parâmetro de correlação para avaliar a efetividade dos tratamentos empregados junto ao processo de reparação muscular. A utilização isolada do UST como técnica de tratamento apresentou melhores resultados em relação às propriedades mecânicas de carga no limite de proporcionalidade, rigidez, resiliência, carga e alongamento máximo. No entanto, a utilização da imobilização gessada por 72 horas associada ou não a estimulação ultra-sônica foi capaz de proporcionar melhorias somente em relação ao alongamento máximo. Sugere-se ainda, que a utilização da imobilização gessada por períodos de 24 horas associada ou não ao uso do UST não foi capaz de apresentar resultados benéficos para as propriedades mecânicas avaliadas
We developed an instrument capable to provoke a muscular injury acute for impact mechanism, in the muscle gastrocnemius of female rats, through a direct and non-invasive. After the production of experimental injury we evaluate the effects of the therapeutic ultrasound (UST), added or not to the cast immobilization, as form of immediate treatment to the muscular injury, for the analysis of the mechanical properties of this muscle. Sixty eight female Wistar rats were used and being divided in seven experimental groups: Group 1 – Intact Control; Group 2 – Without treatment; Group 3 -Immobilization in spica cast for 24 hours; Group 4 - Immobilization in spica cast for 72 hours; Group 5 – Stimulation with UST without immobilization presence; Group 6 - Immobilization in spica cast for 24 hours associated to the stimulation with UST and Group 7 - Immobilization in spica cast for 72 hours associated to the stimulation with UST, treated during six consecutive days with UST, for five minutes daily. We evaluted properties we carry through assays of logitudinal traction in the universal machine of assays and the gotten results had been analyzed statical test. The study it evidenced that the property of proportional limit strength in the was not a good parameter of correlation to evaluate the effectiveness of the employed treatments together to the process of muscular repairing. The isolated use of the UST as treatment technique presented better resulted in relation to the mechanical load properties in the proportional limits, stiffness, resilience, load and strength maximum. However, the use of the spica cast for periods of 72 hours associated or not ultrasound stimulation was not capable to only provide improvements in relation to the maximum strength. One still suggests, that the use of the spica cast in the immobilization for 24 hours periods associate or not to the use of the UST was not capable to present resulted beneficial for the evaluated mechanical properties

Traumatic brain injury (TBI) affects 1.4 million people a year in the United States alone and despite the fact that 96% of people survive a TBI, the health and socioeconomic consequences can be grave, partially due to the fact that very few clinical treatments are available to reduce the damage and subsequent dysfunction following TBI. To better understand the various mechanical, electrical, and chemical events during neural injury, and to elucidate specific cellular events and mechanisms that result in cell dysfunction and death, new high-throughput models are needed to recreate the environmental conditions during injury. This thesis project focuses on the creation of a novel and clinically relevant single-cell injury model of traumatic brain injury (TBI). The implementation of the model requires the development of a novel injury device that allows specialized micro-interfacing functionality with neural micro environments, which includes the induction of prescribed strains and strain rates onto neural tissue, such as groups of cells, individual cells, and cell processes. The device consists of a high-resolution micro-electro-mechanical-system (MEMS) microtweezer microactuator tool that is introducible into both biological and aqueous environments and can be proximally positioned to specific targets in neural tissue and neural culture systems. This microtweezer, which is constructed using traditional photolithography and micromachining processes, is controllable by a custom developed software-automated controller that incorporates a high precision linear actuator and utilizes a luer-based microtool docking interface. The injury studies will include examination of intracellular calcium concentration over the injury time course to evaluate neuronal plasma membrane permeability, which is a significant contributor to secondary injury cascades following initial mechanical insult. Mechanical strain and strain rate input tolerance criteria will also be used to determined thresholds for cellular dysfunction and death.

Дисертація присвячена вивченню особливостей будови ділянки шкіри в процесі регенерації механічного дефекту у віковому аспекті при використанні хітозанових мембран. За допомогою сучасних методів дослідження було вперше вивчено особливості репаративної регенерації шкіри за умов її механічної травми на основі фаз ранового процесу у віковому аспекті. Вперше було виявлено достовірну різницю між традиційними підходами та застосуванням хітозанових мембран із метою лікування механічних ран шкіри. Експериментальні покриття одержали більш виражений терапевтичний ефект. Виявлено, що хітозан підсилює макрофагальну реакцію, що свідчить про активацію функції фагоцитозу, що у свою чергу, приводить до зменшення мікробної контамінації механічної рани. Зменшення площі поверхні дефекту при застосуванні хітозану достовірно вище, ніж без використання лікарських засобів. Уперше встановлено, що при загоєнні ран шкіри під впливом хітозану відбувається швидке формування грануляційної тканини з добре розвиненим мікроциркуляторним руслом, великою кількістю і поліморфізмом клітин і волокнистих структур.
Диссертация посвящена изучению особенностей строения участка кожи в процессе регенерации механического дефекта в возрастном аспекте при использовании хитозановых мембран. С помощью современных методов исследования впервые изучены особенности репаративной регенерации кожи в условиях ее механической травмы на основе фаз раневого процесса в возрастном аспекте. Впервые была выявлена достоверная разница между традиционными подходами и применением хитозановых мембран с целью лечения механических ран кожи. Экспериментальные покрытия получили более выраженный терапевтический эффект. Выявлено, что хитозан усиливает макрофагальную реакцию, что свидетельствует об активации функции фагоцитоза, что в свою очередь, приводит к уменьшению микробной контаминации механической раны. Уменьшение площади поверхности дефекта при применении хитозана достоверно выше, чем без использования лекарственных средств. Впервые установлено, что при заживлении ран кожи под влиянием хитозана происходит быстрое формирование грануляционной ткани с хорошо развитым микроциркуляторным руслом, большим количеством и полиморфизмом клеток и волокнистых структур.
Dissertation is devoted to the study of the structural features of skin in the process of regeneration of a mechanical defect in the age aspect after application of chitosan membranes. Features of reparative regeneration of the skin mechanical trauma was studied using modern methods of research based on the phases of wound healing in the age aspect. We found significant difference between traditional approaches and the use of chitosan membranes for the treatment of mechanical skin wound. Experimental wound dressings have shown pronounced therapeutic effect. It revealed that chitosan enhances macrophage response, which indicates by activation of phagocytosis, which in turn, reduces microbial contamination of trauma surface. Reducing the surface area of the defect in the application of chitosan was significantly higher than without the treatment. It was found that the healing of skin wounds under the influence of chitosan leads rapid formation of granulation tissue with well-developed vessels, and a large number of polymorphic cells and fibrous structures. The use of chitosan membranes leads to a significant increase in the area of granulation tissue at the 3rd day of observation in animals of all ages (maximum rate in young animals – 13.21 ± 0.46% (p = 0.0023)). The amount of granulation tissue decreased from the 7th day, indicating the formation of connective tissue regenerate. Total area of the defect was significantly lower compared to the control only in young animals – 0.35 ± 0.05 cm2 (p = 0.0183). Cell compound of the wounds characterized by decreasing in the number of neutrophils and lymphocytes in all periods of observation and the percentage of macrophages and fibroblasts from the 3rd and 7th days, respectively. Maximum number of endothelial cells increased on the 7th day and is depending on the age of – from 3.1 ± 0.16% (p = 0.1075) (old age) to 7.2 ± 0.44% (p = 0.0246) (young animals). Morphometric study in case of chitosan application indicate normalization of vascular reactions, accompanied by a decrease in the relative area of stromal edema in animals and young age from the 3rd day, and in old rats – in 7th day of observation. The relative area of the dermis and blood vessels diameter is reduced only to animals of young age – 6.90 ± 0.47% (p = 0.5481) and 17.77 ± 1.25 mm (p = 0.2051), respectively . These histological studies suggest an earlier beginning of the formation of granulation tissue, especially in young animals (from the 3rd day of observation) and optimization of the formation of connective tissue and epithelialization of the wound surface to the 21st day. Application of chitosan membranes leads to reduction of wound surface colonization by opportunistic pathogens in the early stages of reparative processes in animals and young and adult ages. Up to the 21st day of observation on the wound surface observed the presence of staphylococci and streptococci only in an amount from ≤ 40 to ≤ 102 CFU / ml.

З інтенсифікацією життєдіяльності людини збільшується ризик травматизації людини в побуті, на виробництві, що пов’язаний з урбанізацією суспільства. В зв’язку з цим збільшується кількість випадків механічного ураження шкірних покривів, яке проявляється у вигляді саден, порізів, розривів шкіри. Вони виникають внаслідок дії чинника безпосередньо на шкіру. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/32057

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O constante aperfeiçoamento dos testes genéticos, como o Teste de Micronúcleos (MN), os tornaram importantes auxiliares na prevenção do câncer. Com o objetivo de melhor compreender a etiologia do desenvolvimento de neoplasias bucais, o presente trabalho se propôs a estudar a influência do fumo, álcool, trauma mecânico e de substância contidas em colutórios sobre a Freqüência de Micronúcleos (FMN) em células epiteliais bucais de alunos do curso de Odontologia. Para tanto, 40 alunos foram divididos em 4 grupos assim caracterizados G1 – Abstêmios (controle); G2 Alcoolistas; G3 – Usuários de aparelho ortodôntico; G4 – Fumantes alcoolistas, e submetidos ao TMN. Posteriormente estes mesmos alunos receberam de forma aleatória, 4 diferentes tratamentos, por 10 dias, a base de colutórios: T1 (óleos essenciais), T2 (álcool 11%), T3 (álcool, 11% + clorexidina 0,12%), T4 (clorexidina 0,12%), sendo então novamente submetidos ao TMN. Os resultados da FMN demonstraram diferenças significativas entre os 4 grupos G (p = 0,043 Kruskal-Wallis), sendo indicado diferença entre G1 e G3 (Mann-Whitney p ? 0,01) e entre G1 e G4 (Mann-Whitney p ? 0,05), contudo, em relação aos tratamentos com colutórios, todos os tratamentos T não alcançaram resultados significativos (Wilcoxon p > 0,05). Os resultados sugerem que o trauma mecânico causado por aparelho ortodôntico assim como a associação de fumo com bebidas alcoólicas favorecem um aumento na prevalência de MN quando comparados ao controle. A utilização de colutórios bucais, em curto prazo, não foi capaz de causar aumento na freqüência de Micronúcleos

Introdução: No período de hipermetabolismo em que se encontra o paciente politraumatizado, é necessário que a administração calórica seja adequada e suficiente para suprir o intenso gasto energético do organismo. Com suporte nutricional inadequado, as reservas de aminoácidos dos músculos esqueléticos e respiratórios são exigidas, expondo o paciente crítico ao risco nutricional e suas consequências. Objetivos: Quantificar o aporte calórico administrado a pacientes em ventilação mecânica (VM), analisar a adequação da prescrição e correlacionar as calorias ofertadas com o tempo em VM. Métodos: Estudo de coorte prospectivo observacional conduzido na Unidade de Terapia Intensiva de um hospital público de Porto Alegre (RS) no período de abril de 2008 a julho de 2009. Foram estudados 60 pacientes politraumatizados em Nutrição Enteral e VM e internados por mais de 5 dias na UTI. Foram verificados o tempo de permanência em VM e a oferta calórica durante o período que permaneceram em terapia nutricional enteral. Resultados: A média do percentual de calorias administradas foi de 68,6% (±12,3) do prescrito. Nove pacientes (15,0%) receberam menos da metade do que deveriam, apenas 16 (26,7%) receberam no mínimo 80,0%. Apenas 25,0% dos pacientes receberam prescrição calórica adequadamente (entre 90% e 110%). Não houve associação significativa entre o Valor Energético Total administrado e o tempo de VM (rs=0,130; p=0,321), tempo de UTI (rs=-0,117; p=0,372) e tempo de internação hospitalar (rs=-0,152; p=0,246). Conclusão: Neste estudo foi verificado que maioria dos pacientes politraumatizados em ventilação mecânica não recebeu um aporte energético adequado, ficando assim expostos aos riscos da desnutrição e seus desfavoráveis desfechos clínicos.
Introduction: During the period of hypermetabolism faced by multiple trauma patients, their calorie intake has to be appropriate and sufficient to meet their high energy expenditure. When there is not appropriate nutritional care, the amino acids from the skeletal and respiratory muscles are used; thus critical patients are exposed to nutritional risk and its consequences. Objectives: To quantify the calories provided to patients on mechanical ventilation (MV); to analyze the appropriateness of the prescription; and to correlate the calories offered with the period of time on MV. Methods: Prospective observational cohort study conducted at the intensive care unit (ICU) of a public hospital in Porto Alegre (RS), Brazil, from April 2008 to July 2009. We studied 60 multiple trauma patients on MV receiving enteral nutrition who remained longer than 5 days at the ICU. We investigated the length of time patients were on MV and their calorie intake while receiving enteral nutrition. Results: The mean percentage of calories was 68.6% (±12.3) of the amount prescribed. Nine patients (15.0%) received less than half of the prescription. Only 16 (26.7%) patients received at least 80.0%. Only 25.0% of patients received the amount of calories according to the prescription (between 90% and 110%). There was no significant association between total energy value and the period of time on MV (rs = 0.130, p = 0.321), length of ICU stay (rs = -0.117, p = 0.372), and length of hospital stay (rs = -0.152, p = 0.246). Conclusion: We found that most multiple trauma patients on MV did not receive an adequate energy intake; therefore, they were exposed to the risks of malnutrition and its adverse clinical outcomes.

ABSTRACT South Africa has a high incidence of violence and death due to unnatural causes. Gunshot and/or multiple stab wounds to the trunk are consequently injuries commonly seen in South African hospitals. Penetrating injuries often necessitate explorative surgical intervention to identify and treat injuries to the internal organs. Patients are managed in the intensive care unit and frequently return to theatre for abdominal lavage prior to eventual wound closure. Critical illness with prolonged mechanical ventilation and immobilization results in some degree of muscle dysfunction. Survivors of critical illness suffer from poor functional capabilities and decreased quality of life. No formal rehabilitation programmes exist in South Africa for these patients following discharge. Purpose: To determine if patients that survived penetrating trunk trauma recover adequately spontaneously following critical illness over the first six months following discharge from the hospital. Methods: A prospective, observational study was conducted. Patients with penetrating trunk trauma were recruited from four intensive care units in Johannesburg. Patients who received mechanical ventilation < 5 days were placed in Group 1 and those who received mechanical ventilation 5 days were placed in Group 2. Lung function tests, dynamometry, quality of life, six-minute walk distance and oxygen uptake tests were performed over six months following discharge from the hospital. The obtained results for dynamometry, exercise capacity and quality of life were compared between groups and to that measured for a healthy (age and sex-matched) control group. Results and Discussion: No pulmonary function abnormalities were detected for subjects in Groups 1 or 2. Distance walked during 6MWD test was significantly reduced for subjects in Group 2 compared to the control group [one-month (p = 0.00), three-months (p = 0.00)]. Morbidity correlated significantly with distance walked by subjects in Group 2 during 6MWD test [three-months (p = 0.03), six-months (p = 0.02)]. No statistically significant differences were found between subjects during the VO2peak test although subjects in Group 1 performed better clinically than those in Group 2. At one-month there was a significant reduction in upper and lower limb strength for subjects in Group 2 compared to those in Group 1 and the controls (p = 0.00 – 0.04). Similar results were detected at the three- and six-month assessments. ICU and hospital length of stay did demonstrate a significant relationship with muscle strength at one and three months following discharge for subjects in Group 2. Severity of illness and morbidity in ICU did not have a significant relation to muscle strength for subjects in Groups 1 or 2 at any of the assessments. Subjects in Group 1 had a significant reduction in right deltoid and triceps strength compared to the controls at one-month (p = 0.00 respectively) only. No significant differences in upper and lower limb muscle strength were detected between the control group and subjects in Group 1 three and six months after discharge. Subjects in both groups had similar limitations in physical and mental aspects of quality of life one-month after discharge. Subjects in Group 1 reported a quality of life comparable to the control group by three-months. Subjects in Group 2 had significant limitations in the physical components of quality of life at three- and six-months compared to those in Group 1 and the controls [p = 0.00 – 0.02]. Conclusion: Subjects in Group 1 recovered adequately on their own within three months after discharge from hospital with regard to muscle strength, exercise capacity and all aspects of quality of life. Subjects in Group 2 presented with significant limitations in exercise capacity, muscle strength and the physical aspects of quality of life even at six months after discharge. Impaired function was related to the duration of critical illness and immobility. A physiotherapist-led rehabilitation programme may be indicated for survivors of penetrating trunk trauma that received prolonged mechanical ventilation to address cardiovascular endurance and peripheral muscle strength retraining between one and three months after discharge to address the physical disabilities observed in these subjects.

Thoracic injury is the most dominant segment of automotive side impact traumas. A numerical model that can predict such injuries in crash simulation is essential to the process of designing a safer motor vehicle. The focus of this study was to develop a numerical model to predict lung response and injury in side impact car crash scenarios. A biofidelic human body model was further developed. The geometry, material properties and boundary condition of the organs and soft tissues within the thorax were improved with the intent to ensure stress transmission continuity and model accuracy. The thoracic region of the human body model was revalidated against three pendulum and two sled impact scenarios at different velocities. Other body regions such as the shoulder, abdomen, and pelvis were revalidated. The latest model demonstrated improvements in every response category relative to the previous version of the human body model. The development of the lung model involved advancements in the material properties, and boundary conditions. An analytical approach was presented to correct the lung properties to the in-situ condition. Several injury metric predictor candidates of pulmonary contusion were investigated and compared based on the validated pendulum and sled impact scenarios. The results of this study confirmed the importance of stress wave focusing, reflection, and concentration within the lungs. The bulk modulus of the lung had considerable influence on injury metric outcomes. Despite the viscous criterion yielded similar response for different loading conditions, this study demonstrated that the level of contusion volume varied with the size of the impact surface area. In conclusion, the human body model could be used for the analysis of thoracic response in automotive impact scenarios. The overall model is capable of predicting thoracic response and lung contusion. Future development on the heart and aorta can expand the model capacity to investigate all vital organ injury mechanisms.

Although there have been tremendous improvements in crash safety there has been an increasing trend in side impact fatalities, rising from 30% to 37% of total fatalities from 1975 to 2004 (NHTSA, 2004). Between 1979 and 2004, 63% of AIS≥4 injuries in side impact resulted from thoracic trauma (NHTSA, 2004). Lateral impact fatalities, although decreasing in absolute numbers, now comprise a larger percentage of total fatalities. Safety features are typically more effective in frontal collisions compared to side impact due to the reduced distance between the occupant and intruding vehicle in side impact collisions. Therefore, an increased understanding of the mechanisms governing side impact injury is necessary in order to improve occupant safety in side impact auto crash. This study builds on an advanced numerical human body model with focus on a detailed thoracic model, which has been validated using available post mortem human subject (PMHS) test data for pendulum and side sled impact tests (Forbes, 2005). Crash conditions were investigated through use of a modified side sled model used to reproduce the key conditions present in full scale crash tests. The model accounts for several important factors that contribute to occupant response based on the literature. These factors are; the relative velocities between the seat and door, the occupant to door distance, the door shape and compliance. The side sled model was validated by reproducing the crash conditions present in FMVSS 214 and IIHS side impact tests and comparing the thoracic compression, velocity, and Viscous Criterion (VC) response determined by the model to the response of the ES-2 dummy used in the crash tests. Injury was predicted by evaluating VCmax, selected for its ability to predict rate-sensitive soft tissue injury during thoracic compression (Lau & Viano, 1986). The Ford Taurus FMVSS 214 and Nissan Maxima IIHS tests were selected from side impact crash test data found in the NHTSA database because they included factors not present in standard side impact test procedures. These factors were; the presence of door accelerometers used to provide input velocities to the side impact model and the use of a ES-2 (rather than the SID) to facilitate comparison of VC response to the human body model. Also, the two crash test procedures (FMVSS 214 & IIHS) were selected to ensure accurate side impact model response to different impact scenarios. The side impact model was shown to closely reproduce the timing and injury response of the full-scale FMVSS 214 side impact test of a Ford Taurus, as well as the IIHS side impact test of a Nissan Maxima. The side impact model was then used to investigate the effects of door to occupant spacing, door velocity profile, armrest height, seat foam, restraint system, and arm position. It was found that the VCmax was controlled by both the first and second peaks typically found in door velocity profiles, but the effect of each varies depending on the situation. This study found that VCmax was reduced by 73-88% when door intrusion was eliminated compared to the VC response incurred by an intruding door. Also, the presence of a deformable door based on physical geometry and material characteristics rather than a simplified rigid door reduced VCmax by 16% in this study. The study on seat foam determined that significant effects on VC response can be made by modest adjustments in foam properties. Low stiffness seat foam was found to increase VCmax by 41% when compared to the VC response when using high stiffness foam. Arm position has been proven to be a relevant factor in side impact crash. Positioning the arms parallel to the thorax, in the “down” position, caused a 42% increase in VCmax when compared to the VC response determined with the arms positioned at 45 degrees. Finally, although restraint systems have limited influence on side impact crash safety compared to front and rear impacts, this study found that the presence of a pre-tensioning restraint system reduced VCmax by 13% when compared to the VC response of an un-belted occupant. It should be noted that the current study was limited to velocity profiles obtained from a specific FMVSS 214 test and therefore results and observations are restricted to the confines of the input conditions used. However, the side impact model developed is a useful tool for evaluating factors influencing side impact and can be used to determine occupant response in any side impact crash scenario when the appropriate input conditions are provided.

The research study investigates the trauma experienced by Metrorail train drivers. An Employee Assistance Programme (EAP) is a worksite-based programme that assists in dealing with employee’s problems that impact on their job performance and overall production. Trauma awareness and management through therapy are necessary components and contribute to the effective operation of EAP. The study was conducted within the framework of a survey. Face-to-face scheduled interviews were designed and conducted on employees, i.e. Metrorail train drivers, after their respective supervisors had given permission. From the feedback on these interviews, it was apparent that train drivers need the help of EAP services, maybe through psychological counselling and motivation. Witnessing suicides by people on rail tracks apparently is a common occurrence to Metrorail train drivers. These accidents leave them emotionally scarred and haunted for almost their entire lives. EAP services will embrace other elements influencing the performance and occupational well-being of these train drivers. These elements include performance incentives, fringe benefits, security, and conducive train settings.
Dissertation (MSD (Employee Assistance Programme))--University of Pretoria, 2006.
Social Work
unrestricted

Tesis (Lic. en Física)--Universidad Nacional de Córdoba, Facultad de Matemática, Astronomía, Física y Computación, 2018.
En este trabajo se intenta presentar un marco teórico que permita la descripción de un sistema unidimensional compuesto por pocas partículas interactuantes mediante un potencial de esferas rígidas atrapadas en una trampa armónica. Se busca mejorar la descripción del sistema introduciendo un potencial que de cuenta del tamaño de las partículas. El potencial de esferas rígidas introduce entonces el efecto que el radio de las partículas tiene sobre el espectro de energías y las funciones de onda del sistema. Finalmente, se estudia el efecto de introducir impurezas en un sistema de tres partículas.
In this thesis we attempt to present a theoretical framework that allows the description of a one dimensional system of few particles interacting by a hard spheres potential, trapped in a one dimensional harmonic trap. We seek to improve the description of the system by introducing a potential that incorporates the size of the particles. The hard spheres potential then introduces the effect that the radius of the particles has on the energy spectrum and the wave functions of the system. Finally, we studied the effect of introducing impurities in a three particle system.