Implementación de un modelo porcino de trasplante hepático en Chile / Implementation of a porcine liver transplant model in Chile

Resumen Objetivo: Presentar la implementación del primer modelo porcino de trasplante hepático (TH) en Chile y sus resultados. Material y Método: Se implementó un protocolo quirúrgico y anestésico en el contexto de una investigación en perfusión normotérmica hepática financiada por un Fondo Nacional de Desarrollo Científico y Tecnológico. Los cerdos fueron seleccionados por peso (35-40 kilos), en cada experimento se utilizó dos, donante y receptor, sometidos a procura y trasplante respectivamente. El análisis se realizó con estadística descriptiva. Resultados: Se realizaron 26 experimentos (marzo de 2018-octubre de 2019). El protocolo consta de 7 etapas: Preparación, Instrumentalización, Procura o Hepatectomía, Tiempo Anhepático, Etapa de Isquemia-Reperfusión, Monitorización y Eutanasia. Las primeras tres son similares en ambos cerdos, y desde la cuarta en adelante corresponde sólo al receptor. La supervivencia a la cirugía fue de 92,3% (24/26) y al seguimiento de 76,9% (20/26). La mortalidad se produjo por inestabilidad cardiovascular postreperfusión portal. El tiempo quirúrgico promedio fue de 170 min, y el tiempo anhepático de 33 min. La PAM cursó una baja postreperfusión con recuperación al final de la monitorización (67,4 mmHg media) y la tendencia en ph fue a acidosis al final del seguimiento (7,21 media). Se requirió drogas vasoactivas en 12 casos. Discusión: Logramos implementar un modelo experimental simplificado y reproducible de TH sin necesidad de circulación extracorpórea ni puente veno-venoso gracias a la estandarización de la técnica quirúrgica y de los cuidados perioperatorios. Conclusiones: La consolidación de un modelo experimental significa el primer paso en investigación preclínica de nuevas tecnologías asociadas al TH en Chile.

Objective: To Present the implementation of the first porcine model of liver transplant in Chile and its results. Materials and Methods: In the context of an investigation based on normothermic perfusion that was subsidized by the National Fund for Scientific and Technological Development, surgical and anesthetic protocols were implemented. Two pigs were selected by weight (35-40 kg), in which one was a donor and the other a receptor; submitted to procure and as a transplant recipient, respectively. The analysis was executed with descriptive statistics. Results: 26 experiments (June 2018-October 2019) were performed. The protocol includes 7 stages: Preparation, Instrumentalization, Procure or Hepatectomy, Anhepatic Time, Phase of Ischemia-Reperfusion, Monitoring and Euthanasia. The first three stages are similar in both pigs; meanwhile the last four are exclusive to the receptor. 92.3% (24/26) survived the surgery and 76.9% (20/26) survived the follow up, including the pilots. Average surgical time was 170 minutes, and the anhepatic time was 33 minutes. The mean arterial pressure decreased after the reperfusion and it improved towards the end of the monitorization (67,4 mmHg average) In the follow up, pigs presented acidosis (7.21 average). Vasoactive drugs were necessary in 12 experiments. Discussion: We managed to implement a simple and reproducible model of porcine liver transplant without extracorporeal circulation or veno-venous by-pass. This was possible due to the standardization of surgical technique and perioperative cares. Conclusions: The consolidation of porcine liver transplant model is the first step in pre-clinical research for the development of new technologies in liver transplant in Chile.

Morphological changes in the tissue structures afeter thermal burns on the background of using dermarm wound dressing

Over the last decade, the interest in using bacterial cellulose in medicine has increased. The article publishes the data about the efficiency of healing burn wounds in rabbits in experimental conditions with the use of the DermaRM wound dressing, compared to the traditionally used Panthenol ointment and the Branolind N salve dressing

Analgesia de animais de laboratório: responsabilidade dos comitês de ética e obrigação dos pesquisadores / Laboratory animals and analgesia: the responsibility of ethics committees and the obligations of researchers / Analgesia de animales de laboratorio: responsabilidad de los comités de ética y obligación de los investigadores

Objetivando avaliar projetos submetidos ao Comitê de Ética no Uso de Animais em relação ao uso de analgesia em cirurgia experimental, este trabalho avaliou 106 projetos, coletando as seguintes informações: metodologia do procedimento cirúrgico, utilização de analgesia, justificativa do não uso de analgésico e aplicação do grau de invasividade. Dos projetos avaliados, 64,2% empregaram técnica cirúrgica. Destes, 65,6% não utilizaram analgesia no pós-operatório, sendo a principal justificativa a de que o analgésico poderia alterar os resultados; em 17%, empregou-se a classificação de grau de invasividade de forma irregular. Assim, o estímulo e a divulgação dos conhecimentos relacionados a analgesia devem partir tanto dos comitês responsáveis quanto do corpo de pesquisadores.

The aim of the present study was to evaluate projects submitted to an Animal Research Ethics Committee regarding the use of analgesia in experimental surgery. A total of 106 projects submitted to the Animal Research Ethics Committee were evaluated and the following information was collected: methodology of the surgical procedure, use of analgesia, justification of the non-use of analgesia and application of the degree of invasiveness. Of the projects evaluated, 64.2% used surgical techniques, of which 65.6% did not use analgesia postoperatively, with the main reason being that the analgesic could alter the results. In 17% of cases the classification of the degree of invasiveness was used in an irregular manner. The stimulation and dissemination of analgesia-related knowledge must stem from both the ethics committees responsible and researchers.

Con el objetivo de evaluar los proyectos presentados al Comité de Ética en el Uso de Animales con respecto al uso de la analgesia en cirugía experimental de animales, este estudio evaluó 106 proyectos y obtuvo la siguiente información: la metodología de la intervención quirúrgica, el uso de la analgesia, la justificación de no utilizar analgésico y la aplicación del grado de invasividad. De los proyectos evaluados, un 64,2% empleó técnicas quirúrgicas, de los cuales un 65,6% no utilizó analgesia en el postoperatorio, justificando principalmente que el analgésico podría alterar los resultados, y en un 17% la clasificación del grado de invasividad se utilizó de manera irregular, por lo que la estimulación y la difusión de los conocimientos relacionados con la analgesia deben partir tanto de los comités responsables como del cuerpo de investigadores.

¿Existe infiltración grasa del cuádriceps en la lesión crónica del tendón patelar? / Is there fatty infiltration of the quadriceps in the chronic rupture of the patellar tendon?

No existen modelos que evalúen los cambios morfológicos musculares en roturas crónicas del aparato extensor de la rodilla. Objetivos: 1) Describir un nuevo modelo experimental de lesión crónica de tendón patelar; y 2) evaluar macroscópica e histológicamente la evolución, a través del tiempo, de la degeneración del cuádriceps con este modelo. Hipótesis: Existe fibrosis e infiltración grasa progresiva del cuádriceps a través del tiempo. Materiales y método: Se realiza transección del tendón patelar en 20 ratones BKS, machos, adultos, divididos en 4 grupos de 5 animales cada uno, siendo sacrificados a la 1era, 2da, 4ta y 12va semanas. A todos los ratones sacrificados se les extrajo el cuádriceps derecho (intervención) e izquierdo (control). Se realizó evaluación macroscópica, análisis morfométrico e histológico por 2 patólogos independientes y ciegos. Los resultados se analizaron estadísticamente con Test T de Student y Test de Wilcoxon (p<0,05). Resultados: Macroscopia: tejido amarillento en grupo intervenido con variables morfométricas alteradas progresivamente de manera significativa desde la 2da semana. Histología: infiltración grasa con atrofia numérica de fibras musculares, progresiva en el tiempo, significativa desde la 4ta semana, llegando a infiltración grasa severa a las 12 semanas con porcentaje de fibrosis menor al 6 por ciento en todos los casos.Conclusiones: Este nuevo modelo de lesión de tendón patelar se asocia a pérdida de continuidad persistente del aparato extensor con cambios estructurales del cuádriceps. Estos cambios incluyen atrofia muscular macroscópica e infiltración grasa con atrofia numérica de fibras musculares progresiva, significativa a partir de la 2da semana...

There are no models that evaluate the morphological changes of the muscles in chronic ruptures of the extensor apparatus of the knee. Objectives: 1) To describe a new model of chronic rupture of the patellar tendon; and 2) To macroscopically and histologically evaluate progressive quadriceps muscle degeneration. Hypothesis: There is progressive fibrosis and fatty infiltration of the quadriceps muscle. Materials and method: A complete transection was performed on the right patellar tendon of 20 male, adult, BKS mice, divided into 4 groups of 5 animals. The animals were sacrificed at the 1st, 2nd, 4th, and 12th week after the indicated procedure. After sacrificing the animals, both quadriceps muscles were resected and evaluated macroscopically, morphometrically, and histologically by 2 independent, blinded pathologists. Statistical analysis was performed using Student t test, and Wilcoxon's test (P<.05). Results:Macroscopy yellowish muscle tissue with significant progressive morphological changes beginning at week 2. Histology: progressive fatty infiltration with numerous atrophies of the muscle fibres, becoming significant after the 4th week, reaching severe fatty infiltration at week 12, with little fibrous tissue in less than 6 percent of the muscle. Conclusions: This new model of patellar tendon chronic rupture is associated with persistent discontinuity of the knee extensor mechanism and structural changes of the quadriceps muscle. These changes include muscle atrophy and progressive fatty infiltration beginning at the 2nd week after the injury...

CRITICAL ANALYSIS OF EXPERIMENTAL MODEL FOR STUDY OF ADHESIONS AFTER INCISIONAL HERNIAS INDUCED IN RATS’ AND REPAIR OF ABDOMINAL WALL WITH DIFFERENT BIOMATERIALS / ANÁLISE CRÍTICA DE MODELO EXPERIMENTAL PARA ESTUDO DAS ADERÊNCIAS APÓS HÉRNIAS INCISIONAIS INDUZIDAS EM RATOS E REPARO DA PAREDE ABDOMINAL COM DIFERENTES BIOMATERIAIS

Background: Adhesions induced by biomaterials experimentally implanted in the abdominal cavity are basically studied by primary repair of different abdominal wall defects or by the correction of incisional hernias previously performed with no precise definition of the most appropriate model. Aim: To describe the adhesions which occur after the development of incisional hernias, before the prosthesis implantation, in an experimental model to study the changes induced by different meshes. Methods: Incisional hernias were performed in 10 rats with hernia orifices of standardized dimensions, obtained by the median incision of the abdominal wall and eversion of the defect edges. Ten days after the procedure adhesions of abdominal structures were found when hernias were repaired with different meshes. Results:The results showed hernia sac well defined in all rats ten days after the initial procedure. Adhesions of the greater omentum occurred in five animals of which two also showed adhesions of small bowel loops besides the omentum, and another two showed liver adhesions as well as the greater omentum, numbers with statistical significance by Student's t test (p<0.05). Conclusion:Although it reproduces the real clinical situation, the choice of experimental model of incisional hernia repair previously induced implies important adhesions, with possible repercussions in the evaluation of the second operation, when different implants of synthetic materials are used.

Racional: As aderências induzidas por biomateriais implantados experimentalmente na cavidade abdominal são estudadas basicamente com o reparo primário de diferentes defeitos produzidos na parede abdominal ou com a correção de hérnias incisionais realizadas previamente, sem definição precisa do modelo mais adequado.Objetivo: Descrever as aderências que ocorrem após o desenvolvimento de hérnias incisionais, antes do implante de próteses, em modelo experimental para estudo de alterações induzidas por diferentes biomateriais.Métodos: Foram realizadas hérnias incisionais em 10 ratos, com orifícios herniários de dimensões padronizadas, obtidos pela incisão mediana da parede abdominal e eversão das bordas do defeito. Após 10 dias foram evidenciadas aderências de estruturas abdominais quando as hérnias foram reparadas com diferentes próteses.Resultados: Foi possível evidenciar hérnias com saco herniário bem definido em todos os ratos já no décimo dia após o procedimento inicial. Aderências do omento maior ocorreram em cinco animais, dos quais dois também apresentaram aderências de alças do intestino delgado além do omento, e outros dois aderências do fígado juntamente com o omento maior, números com significância estatística pelo teste t de Student (p<0,05).Conclusão: A opção por modelo experimental de reparo de hérnia incisional previamente induzida, embora mimetize a situação clínica real, implica em aderências importantes, com possível repercussão na avaliação da segunda operação, quando são utilizados diferentes implantes de material sintético.

Lobectomía en ratas: modelo quirúrgico experimental: resultados en la densidad alveolar / Development of a rat model of lung lobectomy

Introducción: En la literatura está documentado que diferentes mamíferos tienen la capacidad de crecimiento compensatorio post resección pulmonar parcial. Objetivo: Crear un modelo quirúrgico de lobectomía en ratas, factible de desarrollar en nuestro medio, exponiendo algunas originalidades en relación a procedimientos de ventilación pulmonar, comunicando los resultados de la densidad alveolar obtenidos. Animales y Métodos: Se utilizaron 47 ratas Rattus norvegicus. Se aplicó como anestesia Atropina, Quetamina y Xilacina. Para el manejo de la vía aérea se diseñó: 1. Un sistema de ventilación con máscara facial tipo ambú evitando así la intubación traqueal. 2. Un protocolo de evaluación anestésica. 3. Un halo para oxigenar. 4. Se modificó un estetoscopio para realizar auscultación animal. Se practicó una lobectomía pulmonar derecha. Los sujetos fueron separados en Grupo Control (n = 7) y Grupo Experimental (n = 40), estos últimos, separados en cuatro grupos (n = 10, cada grupo), que fueron sacrificados en las semana 1, 2, 3 y 4. Resultados: Se logró 100 por ciento de sobrevida. El número de intersecciones alveolares mostró diferencias significativas entre el grupo control y el grupo experimental sacrificado en la semana 3 (p = 0,0016), con un menor número de alvéolos en el grupo experimental. Conclusión: Es factible realizar un modelo de cirugía pulmonar en ratas, con obtención de un 100 por ciento de sobrevida. Esto se logra por adecuaciones en el manejo pre e intra-operatorio. No se pudo demostrar que exista aumento significativo en el número de alvéolos, posiblemente por el bajo número de casos realizados.

Background: Surgical lung resection is required for multiple pulmonary diseases. After these procedures, the lung experiences a compensatory growth, which can be studied in animal models such as rats. Aim: To develop a surgical model of lung lobectomy in rats. Material and Methods: Forty seven rats of the strain Rattus norvegicus were used. Animals were anesthetized with atropine, ketamine and xylacine. The airway was managed with a facial mask to avoid intubation. An anesthetic evaluation protocol was followed and animals were oxygenated using a cephalic veil. Forty rats were subjected to a right lobectomy and seven animals were sham operated. Rats subjected to lobectomy were sacrificed at one, two, three and four weeks after operation. Results: All operated rats survived. There were significant differences in the number of alveolar intersections among rats subjected to lobectomy and sacrificed at three weeks compared to sham operated animals, with a lower number of alveoli among the former. Conclusions: We were able to develop the model of lobectomy, however we failed to demonstrate a compensatory growth among rats subjected to lobectomy.

Idade dos ratos versus idade humana: qual é a relação? / Rat's age versus human's age: what is the relationship?

RACIONAL: Milhões de ratos são empregados anualmente em pesquisas e no ensino. A exata relação entre a idade dos ratos, comparada com a idade dos humanos ainda é assunto de discussão e controvérsias. OBJETIVO: É revisar a literatura, analisando a idade dos ratos em comparação com a idade dos homens. MÉTODOS: Foram revisadas as publicações existentes sobre o assunto contidas nas bases Medline/Pubmed, Scielo, Biblioteca Cochrane e Lilacs cruzando os descritores ratos, cirurgia experimental e fisiologia. RESULTADOS: Ratos desenvolvem rapidamente durante a infância e se tornam sexualmente maduros com cerca de seis semanas de idade, mas atingem a maturidade social cinco a seis meses mais tarde. Na idade adulta, a cada mês do animal é aproximadamente equivalente a 2,5 anos humanos. Vários autores realizaram trabalhos experimentais em ratos e afirmaram existir correspondência de 30 dias de vida do homem para cada dia de vida do rato. CONCLUSÃO: As diferenças na anatomia, fisiologia, desenvolvimento e fenômenos biológicos devem ser levados em consideração quando são analisados os resultados de qualquer pesquisa em ratos em que a idade é um fator crucial. Cuidado especial é necessário ser tomado quando os estudos efetuados pretendem produzir correlação com a vida humana. Para isso, atenção especial é necessária para verificar a fase em dias do animal e sua correlação com os anos em humanos.

BACKGROUND: Millions of mice are used annually in research and teaching. The exact relationship between age of the animals compared with the age of humans is still subject to discussion and controversy. OBJECTIVE: Literature review analyzing the age of rats in comparison with men age. METHODS: Were reviewed the existing publications on the subject contained in Medline / Pubmed, Scielo, The Cochrane Database of Systematic Reviews and Lilacs crossing the headings rats, experimental surgery and physiology. RESULTS: Rats rapidly develop during childhood and become sexually mature at about six weeks old, but reach social maturity five to six months later. In adulthood, every month of the animal is approximately equivalent to 2.5 human years. Several authors performed experimental studies in rats and estimated 30 days of human life for every day life of the animal. CONCLUSION: The differences in anatomy, physiology, development and biological phenomena must be taken into consideration when analyzing the results of any research in rats when age is a crucial factor. Special care is necessary to be taken when the intention is to produce correlation with human life. For this, special attention is needed to verify the phase in days of the animal and its correlation with age in years of humans.

Aspectos fundamentais da experimentação animal - aplicações em cirurgia experimental / Fundamental aspects on animal research as applied to experimental surgery

Com o objetivo de contribuir à pesquisa em cirurgia experimental, este artigo apresenta uma análise dos principais parâmetros exigidos a serem observados pelos comitês internacionais e nacionais de ética e bem-estar animal, cujo cumprimento é pré-requisito para publicação em periódicos arbitrados de circulação internacional. A padronização da genética, do estado sanitário e do ambiente das espécies de animais Mus musculus (camundongos), Rattus norvegicus (ratos), Oryctolagus cuniculus (coelhos) e Sus scropha domesticus (suínos), a observação de condições adequadas no transporte, aclimatação, enriquecimento do ambiente, treinamento de técnicos em experimentação animal, gestão de informação, biossegurança, dieta, anestesia, cuidados pós-operatórios, analgesia e eutanásia, aliados a projetos de pesquisa bem planejados são apresentados como etapas fundamentais para a obtenção de resultados com alto grau de acuidade, alto nível de reprodutibilidade e precisão.

This study aimed to present the general principles for experiments performed on laboratory animals as required by international and national ethical committees on animal welfare. Compliance to these principles is a prerequisite for publication in international journals. Details of genetic, sanitary and environmental standards, transportation, acclimation, environmental enrichment, appropriate education and training of all those involved in handling of live animals, information management strategy, biossecurity, diet, anesthesia, analgesia, postoperative care and euthanasia for Mus musculus (mice), Rattus norvegicus (rat), Oryctolagus cuniculus (rabbit) and Sus scropha domesticus (pig) combined with well planned biomedical research are fundamental to increase the accuracy, reproducibility and precision of the experimental results.

Tendências em experimentação animal / Trends in animal experimentation

Introdução: A busca do entendimento de fatores etiológicos, mecanismos e tratamento das doenças tem levado ao desenvolvimento de vários modelos animais nas últimas décadas. OBJETIVO: Esse artigo tem por objetivo discutir aspectos relacionados a modelos animais de experimentação, escolha do animal e tendências atuais nesse campo em nosso país. Além disso, esse estudo buscou avaliar o espaço ocupado por artigos experimentais em revistas médicas. Métodos: Foram selecionadas cinco revistas brasileiras, indexadas na LILACS, SciELO, MEDLINE, e recentemente incorporadas pelo Institute for Scientific Information Journal of Citation Reports. Foram selecionados pelo resumo ou abstract todos os artigos publicados nessas revistas, nos anos de 2007 e 2008, que empregaram modelos animais. Resultados: Do total de 832 artigos publicados no período pelas revistas analisadas, foram selecionados 92 (11,1 por cento) que empregavam animais de experimentação. O número de artigos experimentais variou de 5,2 por cento a 17,9 por cento do conteúdo global da revista. Nas instruções aos autores de quatro (80 por cento) das revistas avaliadas, havia referência explícita aos princípios éticos na condução de estudos com animais. Os modelos animais induzidos representaram 100 por cento dos artigos analisados neste estudo. O rato foi o animal mais empregado nos artigos analisados, sendo utilizado em 78,3 por cento deles. Conclusões: O presente estudo poderá fornecer subsídios para adoção de políticas editoriais futuras relativas à publicação de artigos originários de pesquisa animal na RBCCV.

Introduction:: The search of the understanding of etiological factors, mechanisms and treatment of the diseases has been taking to the development of several animal models in the last decades. OBJECTIVE: To discuss aspects related to animal models of experimentation, animal choice and current trends in this field in our country. In addition, this study evaluated the frequency of experimental articles in medical journals. Methods: Five Brazilian journals indexed by LILACS, SciELO, MEDLINE, and recently incorporate for Institute for Scientific Information Journal of Citation Reports were analyzed. All the papers published in those journals, between 2007 and 2008, that used animal models, were selected based on the abstracts. Results: Of the total of 832 articles published in the period, 92 (11.1 percent) experimentation papers were selected. The number of experimental articles ranged from 5.2 percent to 17.9 percent of the global content of the journal. In the instructions to the authors, four (80 percent) journals presented explicit reference to the ethical principles in the conduction of studies with animals. The induced animal models represented 100 percent of the articles analyzed in this study. The rat was the most employed animal in the analyzed articles (78.3 percent). Conclusions: The present study can contribute, supplying subsidies for adoption of future editorials policies regarding the publication of animal research papers in Brazilian Journal of Cardiovascular Surgery.

Hernioplastia experimental em coelhos por meio de cartilagem auricular bovina conservada em glutaraldeído / Rabbits experimental hernioplasty by means of bovine auricular cartilage preserved in glutaraldehyde

Avaliou-se a viabilidade do emprego da cartilagem auricular bovina conservada em glutaraldeído a 4 por cento na hernioplastia experimental, empregando-se seis coelhos adultos, machos, da raça Nova Zelândia. Para obtenção da hérnia incisional, removeu-se um segmento elíptico de 3cm de comprimento por 1cm de largura, no ponto central à primeira incisão, envolvendo fáscia e tecido muscular, na região da cicatriz umbilical. Dois animais de cada vez foram sacrificados aos 15, 30 e 45 dias após a cirurgia. Nos sacrificados aos 15 dias, observaram-se áreas focais de inflamação, caracterizadas por abscesso e fístula. À microscopia, observou-se área de inflamação e necrose próxima à periferia do implante. Nas amostras colhidas dos animais sacrificados aos 30 dias, não foram evidenciadas alterações clínicas relevantes. Desses, um animal apresentou à microscopia intensa proliferação fibroblástica, moderada neovascularização e células inflamatórias predominantemente mononucleares. Dos sacrificados aos 45 dias, em um ocorreu aderência de alça intestinal ao implante. É possível inferir que o material implantado apresentou satisfatória compatibilidade com o tecido receptor. Conclui-se que o implante de cartilagem auricular bovina conservada na hernioplastia experimental em coelhos apresentou evidências de boa integração tecidual e cicatrização, não havendo eliminação do material implantado.

The auricular cartilage preserved in 4 percent glutaraldehyde was used for experimental hernioplasty in six male, adult, New Zealand rabbits. To create an incision hernia, an elliptic tissue fragment three centimeter-long and one-centimeter wide was removed at a point centrally located from the first incision, embracing fascia and muscle tissue, from the area of umbilical scar. Animals were euthanized, two at a time, 15, 30, or 45 days after surgery. In the animals euthanized after 15 days focal areas of inflammation were observed, characterized by abscesses and fistulas. The histological section showed areas of inflammation and necrosis next to the periphery of the graft. In the animals euthanized after 30 days, there was no evidence of clinical alterations. Microscopic diagnosis of one of these animals showed intense fibroblastic proliferation, moderate neovascularization and inflammatory cells, predominantly mononuclear. One of the animals submitted to euthanasia at 45 days presented at necropsy adherence of bowel to the graft and impaired reconstitution of the parietal peritoneum. It is possible to infer that the grafted material presented satisfactory compatibility with the receptor tissue. Thus, it may be concluded that auricular bovine cartilage grafts preserved in 4 percent glutaraldehyde in experimental hernioplasty in rabbits presented evidence of good tissue integration and healing, with no elimination of the grafted material.

Consentimiento nnformado en cirugía ortopédica / Informed consent in orthopedics

Esta revisión pretende ser un alto en el camino para quienes ejercen la ortopedia y el trauma en Colombia -y en otras latitudes-, un espacio de reflexión para afrontar el diario vivir, con estudiantes y residentes, pacientes y familiares, colegas y administradores de la salud, al establecer y hacer vida una cultura ética desde la cirugía ortopédica, de tal manera que no se estén recordando principios éticos fundamentales solo cuando aparezcan las quejas de los pacientes o los requerimientos judiciales. Con el hilo central del Consentimiento Informado, su historia, su sentido y momento apropiado de aplicación, se repasan conceptos bioéticos nucleares, partiendo de la buena comunicación, pilar de la relación médico-paciente, que deriva en la necesaria confianza que perfecciona dicha relación. Se ofrecen comentarios, principalmente en el campo de los conflictos de intereses, a la reglamentación que la Asociación Americana de Cirujanos Ortopedistas tiene para regular la práctica profesional de sus asociados.

The present review is intended as a wake-up call for those who work with orthopedics and trauma in Colombia and in other parts of the world. It is an opportunity to reflect on daily practice with students and residents, patients and their families, colleagues and health administrators by establishing and making life an ethical culture from the standpoint of orthopedic surgery, so that we are reminded of fundamental ethical principles at all times, not just when complaints from patients or injunctions arise. Informed consent, its history, meaning and appropriate moment of application are the basis on which nuclear bioethical concepts are reviewed, beginning with good communication, which is the backbone of the physician-patient relationship and from which the confidence necessary to perfect that relationship is derived. Comments are put forth, primarily with respect to conflicts of interest in light of the regulations adopted by the American Association of Orthopedic Surgeons to standardize the professional practice of its members.

Esta revisão deseja ser um alto no caminho dos que exercem a ortopedia e o trauma em Colômbia (e nos outros países), um sitio de reflexão para afrontar o diário viver com estudantes y residentes, pacientes e familiares, colegas e administradores da saúde, ao fixar e fazer viva uma cultura ética desde a cirurgia ortopédica; assim, os princípios éticos básicos no somente se recordarão quando cheguem as queixas dos pacientes ou os requerimentos judiciais. Neste artigo, repassam-se conceitos bioéticos fundamentais -tindo como eixo o consentimento informado, a sua história e o momento apropriado de aplicação- partindo da adequada comunicação, apoio da relação médico-paciente, que leva à confiança necessária que aperfeiçoa esta relação. No campo dos conflitos de interesse, fazem-se comentários à regulamentação da Associação Americana de Cirurgiões Ortopedistas.

Análisis descriptivo de la reparación ósea asociada a implantes dentales endóseos instalados en perros con técnica sumergida en dos períodos de evaluación / Descriptive analyses of osseous repair related to endosseous dental implant installed in dogs with submerged technique in two evaluation period

Los implantes oseointegrados forman parte de la práctica clínica en diferentes disciplinas de la rehabilitación funcional y estética del hombre donde el área de la odontología no es una excepción; de esta forma, los implantes dentales son una respuesta a la gran demanda de paciente con edentulismo parcial o total. Existe una importante y creciente investigación en implantología, siendo imperativo reconocer las características histológicas de la reparación ósea cuando son instalados implantes dentarios. El objetivo de esta investigación es reconocer las características histológicas descriptivas de la reparación ósea asociada a la instalación de implantes dentales en dos periodos de evaluación. El modelo experimental utilizado en este estudio correspondió al de cinco perros sometidos a la exodoncia de premolares mandibulares bilaterales. Después de tres meses fueron instalados implantes bilaterales con dos diseños diferentes y con diferentes protocolos de carga. Los sacrificios de los animales fueron realizados después de tres y seis semanas de instalados los implantes. El estudio histológico descriptivo se desarrolló en el tejido adyacente a implantes instalados con técnica sumergida. Se observaron características de reparación ósea en los dos periodos de evaluación. El periodo de tres semanas presento tejido mineralizado en contacto con el implante y tejido conectivo no mineralizado en aumento desde la región superior hacia la inferior. Las regiones de reparación ósea fueron relacionadas con fenómenos de angiogénesis adyacentes. A las seis semanas se observo una mayor formación ósea, reemplazando las áreas de tejido conectivo no mineralizado por tejido mineralizado. Se observo también tejido óseo maduro con canales de Havers bien constituidos. Concluimos que existe una secuencia biológica de reparación ósea respetada en los dos periodos de evaluación, donde después de seis semanas es posible observar un tejido óseo bien constituido, teóricamente ...

Osseointegrated implants are a part of clinical practice in different areas of the aesthetic and functional human rehabilitation where dentistry is not an exception; being like that, dental implants are a responses to great necessity of patient with partial or total dental lost. Exist an important and crescent research in implantology, being very important to recognize the histological characteristic of the osseous repair when dental implant are installed. The aim of this research was to recognize the histological descriptive characteristic of the osseous repair in two evaluation period. The experimental model in this research was five dogs submitted to dental extraction of mandibular bilateral bicuspid. After three month were installed bilateral implants with two implants design and different load protocols. The animals' sacrifices were realized three and six weeks after implants installation. The histological evaluation was realized in a tissue of implant with submerged techniques. Was observed osseous repair characteristic for two evaluation period. For three weeks period was observed mineralized tissue in contact with implant and non mineralized connective tissue in increase from superior to inferior areas. Reparation areas were related to adjacent angiogenic phenomena. For sex weeks period, was observed a major osseous formation, change connective tissue for mineralized tissue. Was observed too matures osseous tissue with well formed Havers channel. We conclude that exist a biological sequence of osseous repair present for a two evaluation period, where in a sex weeks is observed osseous tissue with good definition, theoretically capable for stress support.

Avaliação da dispersão de curvas força x elongação de segmentos de cólon descendente de ratos por meio do modelo sigmoidal de Boltzmann / Evaluation of the force x elongation curves dispersion of descending colon of rats using Boltzmann's sigmoidal model

OBJETIVO: avaliar a dispersão de curvas Força x Elongação (FE) representativas do comportamento mecânico de alça cólica íntegra de ratos. MATERIAIS E MÉTODOS: dez segmentos de cólon descendente de ratos machos Wistar foram submetidos ao teste biomecânico Energia Total de Ruptura. Cada curva gerada por esse ensaio foi ajustada ao modelo de Boltzmann, o qual correlaciona os valores de força e elongação por meio da combinação dos parâmetros A1, A2, x0 e d x. Nesse contexto, para cada parâmetro, foram calculadas as médias, os desvios padrão e correlações. Após, determinou-se a dispersão resultante da força em todo processo de deformação através de uma análise que considera as correlações entre as grandezas, com base na lei de propagação das incertezas. Para determinar um intervalo no qual estarão contidos 95% dos valores de força, a dispersão resultante foi multiplicada por um fator de abrangência considerando-se uma distribuição normal. RESULTADOS: os valores da média, do desvio padrão e das correlações foram determinados. A dispersão resultante dos valores de força foi expandida, delineando-se limites dentro dos quais estarão contidas as curvas FE para um intervalo de confiança de 95%. CONCLUSÃO: essa metodologia poderá auxiliar na avaliação de variáveis que interfiram no comportamento mecânico intestinal.

PURPOSE: to evaluate the dispersion of Force x Elongation curves (FE) that represents the mechanical behavior of rat's colon. MATERIALS AND METHODS: ten descending colon segments were submitted to the Total Energy of Rupture Test. Each curve generated by this test was fitted to Boltzmann model that correlates the values of force and elongation through the combination of the parameters A1, A2, x0 and d x. Then, for each parameter were calculated the mean, standard deviation and their correlations. Later, the resultant dispersion was determinated in the whole deformation process by an analysis that considers the correlations between the greatnesses based on the propagation of uncertainties law. The resultant dispersion was multiplied by a coverage factor, considering a normal distribution, to determinate an interval in which 95% of force values will be present. RESULTS: the mean, standard deviation and correlation were determined. The resultant dispersion of force values was expanded drawing limits inside which FE curves will be for a confidence interval of 95%. CONCLUSION: this methodology will be possibly used to evaluate variables that act on the intestinal mechanical behavior.

Evaluation of propofol as an anesthetic in swine tracheal transplant surgery / Evaluación del propofol como anestésico para cerdos sometidosa trasplante de tráquea

Because the swine have been used as an ideal animal model for different medical investigations, it has been useful to the advance in vital organs transplant field. The trachea transplant is a surgical procedure which requires special conditions in anesthetic depth and muscular relax, for a long period, and in addition, an excellent intra and post-operatory analgesic. The aim of this study was to use a combination of xylacine and ketamine, as premedication and evaluate propofol as a general anesthetic in trachea transplant donor or recipient pigs. All the methodology was under the approval of the Committee of Ethics for the Experimentation with Animals of the University of Antioquia. Ten donors and 10 recipients female Yorkshire pigs having a body weight of about 30 kg were used. Trachea extraction from a donor and its transplantation to a recipient in the same surgical procedure was performed. The average body weight (PP) was 30 ± 2.92 kg for both the groups, the average value were as follows: time of recumbency (TR) 8.25 ± 2:85 min; latency period (PL) 6.05 ± 1.73 min, (for both groups); surgical time (TQ) for donors and recipients was 80 ± 0.02, and 247 ± 0.02 min, respectively; heartbeat rate (FC) 90.34 ± 8.14 bpm, O2 saturation (SO2) 95.47 ± 1.79 %; exhaled PCO2 31.13 ± 1.89 mmHg; temperature (T) for both groups was 37.51 ± 0.74oC. The mean arterial pressure average (PAM) for both group was 65.47 ± 5.94 mmHg; the average time of esternal recumbecency (TRE) for donor female pigs was 16.50 ± 4.09 min, and the average time to stand up (TP) for swine recipients was 30.70 + 3.27 min. These results indicate that Propofol can be considered as a safe anesthetic for use in continuous perfusion. Since it has not an analgesic effect it is strongly recommended to combine it with opioids during anesthetic-surgical procedures; it can be also used with neuromuscular preanesthetics or inhaled anesthetics.

Los cerdos se han utilizado como modelo animal ideal para diversas investigaciones médicas; han sido útiles para el avance en el trasplante de órganos. El trasplante de tráquea es un procedimiento quirúrgico que requiere condiciones especiales en profundidad anestésica y relajación muscular por un período largo, y además, una analgesia intra y del postoperatoria excelente. Nuestra investigación utiliza una combinación de xylacine y ketamina, como premedicación y evaluar el propofol como anestésico general en cerdos donantes y receptores en quienes el trasplante de la tráquea sería hecho. Toda la metodología contó con la aprobación del Comité de Ética para la Experimentación con los Animales de la Universidad de Antioquia. Utilizamos 10 donantes y 10 cerdos raza Yorkshire hembras con un peso corporal de cerca de 30 kilogramos. Se realizó la extracción de la tráquea de un donante y el trasplante a un receptor en el mismo procedimiento quirúrgico. El peso corporal (PP) fue de 30 ± 2.92 kg para todo el grupo, el tiempo de recumbencia (TR) para ambos grupos fue de 8.25 ± 2.85 min, el período de latencia (PL) para ambos grupos fue de 6.05 ± 1.73 min, el promedio de tiempo quirúrgico (TQ) para los donantes fue de 80 min ± 0.02, el TQ de los receptores fue de  247m ± 0.02. La presión arterial media (PAM) para todo el grupo fue de 65.47 ± 5.94 mmHg, el promedio de frecuencia cardiaca (FC) para ambos grupos fue de 90.34 ± 8.14 ppm, el promedio de saturación de oxigeno (SO2) fue de 95.47 ± el 1.79% y el CO2 espirado fue de 31.13 ± 1.89 mmHg y el promedio de la temperatura (t) para ambos grupos fue de  37.51 ± 0.74oC. La tiempo de recumbencia esternal (TRE) para las cerdas donantes fue de 16.50 ± 4.09 min y el tiempo para pararse (TP) para los receptores fue de 30.70 ± 3.27 min. El propofol se puede considerar como anestésico seguro para el uso en la perfusión continua durante la anestesia. Puesto que no tiene un efecto analgésico se recomienda combinarlo con opioides.

Cryosurgery of Lung with 2.4 mm Cryoprobe: An Experimental in vivo Study of the Cryosurgery in Canine Model / 대한흉부외과학회지

BACKGROUND: The clinical application of cryosurgery for the management of lung cancer is limited because the response of lung at low temperature is not well understood. The purpose of this study is to investigate the response of the pulmonary tissue at extreme low temperature. MATERIAL AND METHOD: After general anesthesia the lungs of twelve Mongrel dogs were exposed through the fifth intercostal space. Cryosurgical probe (Galil Medical, Israel) with diameter 2.4 mm were placed into the lung 20 mm deep and four thermosensors (T1-4) were inserted at 5 mm intervals from the cryoprobe. The animals were divided into group A (n=8) and group B (n=4). In group A the temperature of the cryoprobe was decreased to -120 degrees C and maintained for 20 minutes. After 5 minutes of thawing this freezing cycle was repeated. In group B same freezing temperature was maintained for 40 minutes continuously without thawing. The lungs were removed for microscopic examination on 1 day after the cryosurgery. In four dogs of the group A the lung was removed 7 days after the cryosurgery to examine the delayed changes of the cryoinjured tissue. RESULT: In group A the temperatures of T1 and T2 were decreased to 4.1+/-11 degrees C and 31+/-5 degrees C respectively in first freezing cycle. During the second freezing period the temperatures of the thermosensors were decreased lower than the temperature during the first freezing time: T1 -56.4+/-9.7 degrees C, T2 -18.4+/-14.2 degrees C, T3 18.5+/-9.4 degrees C and T4 35.9+/-2.9 degrees C. Comparing the temperature-distance graph of the first cycle to that of the second cycle revealed the changes of temperature-distance relationship from curve to linear. In group B the temperatures of thermosensors were decreased and maintained throughout the 40 minutes of freezing. On light microscopy, hemorrhagic infarctions of diameter 18.6+/-6.4 mm were found in group A. The infarction size was 14+/-3 mm in group B. No viable cell was found within the infarction area. CONCLUSION: The conductivity of the lung is changed during the thawing period resulting further decrease in temperature of the lung tissue during the second freezing cycle and expanding the area of cell destruction.

Experimental Sciences in Surgery : Harvey Cushing's Work at the Turn of the Twentieth Century / 의사학

No Abstract Available.

The Experimental Study for Myocardial Preservation Effect of Ischemic Preconditioning / 대한흉부외과학회지

BACKGROUND: Decrease in cardiac function after open heart surgery is due to an ischemia induced myocardial damage during surgery, and ischemic preconditioning, a condition in which the myocardial damage does not accumulate after repeated episodes of ischemia but protects itself from damage after prolonged ischemia due to myocytes tolerating the ischemia, is known to diminish myocardial damage, which also helps the recovery of myocardium after reperfusion, and decreases incidences of arrythmia. Our study is performed to display the ischemic preconditioning and show the myocardial protective effect by applying cardioplegic solution to the heart removed from rat. MATERIAL AND METHOD: Sprague-Dawley male rats were used, They were fixed on a modified isolated working heart model after cannulation. The reperfusion process was according to non-working and working heart methods and the working method was executed for 20 minutes in which the heart rate, aortic pressure, aortic flow and coronary flow were measured and recorded. The control group is the group which the extracted heart was fixed on the isolated working heart model, recovered by reperfusion 60 minutes after infusion and preserved in the cardioplegic solution 20 minutes after the working heart perfusion and aortic cross clamp, The thesis groups were divided into group I, which ischemic hearts that were hypoxia induced were perfused by cardioplegic solution and preserved for 60 minutes; group II, the cardioplegic solution was infused 45 seconds (II-1), 1 minutes (II-2), 3 minutes (II-3), after the ischemia induction, 20 minutes after working heart perfusion and aortic cross clamp; and group III, hearts were executed on working heart perfusion for 20 minutes and aortic cross clamp was performed for 45 seconds (III-1), 1minute (III-2), 3 minutes (III-3), reperfused for 2 minutes to recover the heart, and then aortic cross clamping was repeated for reperfusion, all the groups were compared based on hemodynamic performance after reperfusion of the heart after preservation for 60 minutes. RESULT: The recovery time until spontaneous heart beat was longer in groups I, II-3, III-2 and III-3 to control group (p<0.01). Group III-1 (p<0.05) had better results in terms of recovery in number of heart rates compared to control group, and recovered better compared to II-1 (p<0.05). The recovery of aortic blood pressure favored group III-1 (p<0.05) and had better outcomes compared with II-1 (p<0.01). Group III-1 also showed best results in terms of cardiac output (p<0.05) and group III-2 was better compared to II-2 (p<0.05). Group I (p<0.01) and II-3 (p<0.05) showed more cardiac edema than control group. CONCLUSION: When the effects of other organs are dismissed, protecting the heart by infusion of cardioplegic solution after enforcing ischemia for a short period of time before the onset of abnormal heart beats for preconditioning has a better recovery effect in the cardioplegic group with preconditioning compared to the cardioplegic solution itself. we believe that further study is needed to find a more effective method of preconditioning.

Treinamento em microcirurgia vascular: é economicamente viável?

The authors describe their experience at the Experimental Microsurgery Lab of the Plastic Surgery Service of Irmandade Santa Casa de Misericórdia de Porto Alegre Hospital -- Fundação Faculdade Federal de Ciências Médicas de Porto Alegre Medical School, highlighting initial low cost microsurgery training alternatives. They present the experimental results obtained.

Os autores descrevem o trabalho realizado no laboratório de Microcirurgia Experimental do Serviço de Cirurgia Plástica ISCMPA-FFFCMPA, enfatizando alternativas no treinamento inicial de microcirurgia com investimento reduzido, mostrando o resultado experimental obtido

Eficácia da confecção de válvulas colônicas após ressecção retoanal em ratos / Efficacy of colonic valves confection after anorectal resection in rats

OBJETIVO: Testar a eficácia da construção de válvulas colônicas após a ressecção retoanal em ratos, para se obter retardo do fluxo intestinal. MÉTODO: Análise clínico-evolutiva, radiológica e anatomopatológica de 31 ratos submetidos a duas seromiotomias circunferenciais transversais no cólon com invaginação sero-serosa e ressecção retoanal, com colostomia perineal. RESULTADOS: Sete ratos morreram no pós-operatório e, necropsiados, apresentavam impactação fecal. Houve redução do peso corporal e fecal no pós-operatório imediato (estatisticamente não significante), seguida de aparente normalização dos valores. Fecalitos aderidos uns aos outros foram freqüentes. Dos 24 animais radiografados, em oito, ao menos uma das válvulas estava visível. Após a necropsia de 21 ratos, constatou-se o predomínio absoluto de fezes a montante das válvulas. Macroscopicamente, nem sempre as válvulas foram identificadas. Na microscopia, encontrou-se hipertrofia das fibras musculares e interrupção da camada muscular com alteração na disposição das fibras e fibrose nos locais da seromiotomia. CONCLUSÕES: A operação foi tecnicamente viável. A presença das fezes a montante das válvulas, a eliminação de fezes aderidas, a hipertrofia e a interrupção da camada muscular reforçam a hipótese de que a seromiotomia age como mecanismo frenador, retardando o trânsito intestinal. O modelo experimental não permite aferir sobre continência fecal.

BACKGROUND: The present study intend to test the efficacy of colonic valves construction after the anorectal resection in rats, in order to obtain retardation of the intestinal flow. METHOD: Clinical, radiological and anatomopathological analysis, ranging from 31 rats, submited to a series of two colonic transversal-circunferential seromiotomies, followed by serous-serous invagination and anorectal resection, and a perineal colostomy. RESULTS: Seven rats have died in the post-operatorium and, when necropsied, they presented faecal impactation. There was reduction in both body and faecal weight in the immediate post-operatorium period (statistically not significant), followed by an apparent normalization of the values. Small stool were found frequently joined together. In eight animals, from twenty-four which underwent radiograph, at least one valve was visible. After the necropsy of 21 rats, there was a major predominance of faeces above the valves. Macroscopically, the valves were not identified quite often. Microscopically, hipertroph in muscle fibers and interruption in muscle lay with alteration in fibers disposition and fibrosis in the places of seromiotomy, were commomly found. CONCLUSIONS: The operation can be considered as being tecnically viable. The presence of faeces above the valves, the elimination of joined stools, the hipertrophy and interruption of muscle layer, all emphasize the hypothesis that seromiotomy acts as a braking mechanism, retarding the intestinal flow. The experimental model adopted does not allow us to make any gauging regarding to faecal continence.