Effect of three training programs on surgical performance in single-port laparoscopic surgery.

OBJECTIVE: The aim of this study was to evaluate the effect of three training methodologies on the acquisition of psychomotor skills for laparoendoscopic single-site surgery (LESS), using straight and articulating instruments. METHODS: A prospective study was conducted with subjects randomly divided into three groups, who performed a specific training for 12 days using three laparoscopic tasks in a laparoscopic simulator. Group-A trained in conventional laparoscopy setting using straight instruments and in LESS setting using both straight and articulating instruments. Group-B trained in LESS setting using straight and articulating instruments, whereas Group-C trained in LESS setting using articulating instruments. Participants' performance was recorded with a video-tracking system and evaluated with 12 motion analysis parameters (MAPs). RESULTS: All groups obtained significant differences in their performance in most of the MAPs. Group-C showed an improvement in nine MAPs, with a high level of technical competence. Group-A presented a marked improvement in bimanual dexterity skills. CONCLUSIONS: Training in LESS surgery using articulating laparoscopic instruments improves the quality of skills and allows smoother learning curves.

OBJETIVO: Evaluar el efecto de tres métodos de entrenamiento en la adquisición de habilidades psicomotrices para la cirugía laparoendoscópica por puerto único (LESS, laparoendoscopic single-site surgery) utilizando instrumental recto y articulado. MÉTODO: Se realizó un estudio prospectivo con sujetos divididos aleatoriamente en tres grupos, quienes realizaron un entrenamiento específico durante 12 días utilizando tres tareas laparoscópicas en un simulador laparoscópico. El grupo A entrenó en el entorno laparoscópico convencional con instrumentos rectos, y en el entorno LESS con instrumentos rectos y articulados. El grupo B entrenó en el entorno LESS con instrumentos rectos y articulados. El Grupo C entrenó en el entorno LESS con instrumentos articulados. El desempeño de los participantes se registró con un sistema de seguimiento en video y fue evaluado con 12 parámetros de análisis de movimiento (MAP, motion analysis parameters). RESULTADOS: Todos los grupos obtuvieron diferencias significativas en su desempeño para la mayoría de los MAP. El grupo C mostró una mejora en nueve MAP, con un alto nivel de competencia técnica. El grupo A mostró una marcada mejora en la habilidad de destreza bimanual. CONCLUSIONES: El entrenamiento en cirugía LESS con instrumentos articulados mejora la calidad de las habilidades adquiridas y permite curvas de aprendizaje más suaves.

Face, content, and construct validity of the virtual immersive operating room simulator for training laparoscopic procedures.

BACKGROUND: The aim of this work is to present the face, content, and construct validation of the virtual immersive operating room simulator (VIORS) for procedural training of surgeons' laparoscopic psychomotor skills and evaluate the immersive training experience. METHODS: The VIORS simulator consists of an HMD Oculus Rift 2016 with a visor on a 1080 × 1200 pixel OLED screen, two positioning sensors with two adapted controls to simulate laparoscopic instruments, and an acrylic base to simulate the conventional laparoscopic setup. The immersion consists of a 360° virtual operating room environment, based on the EndoSuite at Hospital Infantil de Mexico Federico Gomez, which reproduces a configuration of equipment, instruments, and common distractions in the operating room during a laparoscopic cholecystectomy procedure. Forty-five surgeons, residents, and medicine students participated in this study: 27 novices, 13 intermediates, and 5 experts. They completed a questionnaire on the realism and operating room immersion, as well as their capabilities for laparoscopic procedural training, scored in the 5-point Likert scale. The data of instrument movement were recorded and analyzed using 13 movement analysis parameters (MAPs). The experience during training with VIORS was evaluated through NASA-TLX. RESULTS: The participants were enthusiastic about the immersion and sensation levels of the VIORS simulator, with positive scores on the realism and its capabilities for procedural training using VIORS. The results proved that the VIORS simulator was able to differentiate between surgeons with different skill levels. Statistically significant differences were found in nine MAPs, demonstrating their construct validity for the objective assessment of the procedural laparoscopic performance. At cognitive level, the inversion experience proves a moderate mental workload when the laparoscopic procedure is carried out. CONCLUSION: The VIORS simulator has been successfully presented and validated. The VIORS simulator is a useful and effective device for the training of procedural laparoscopic psychomotor skills.

Perfusion Decellularization of Extrahepatic Bile Duct Allows Tissue-Engineered Scaffold Generation by Preserving Matrix Architecture and Cytocompatibility.

Reconstruction of bile ducts damaged remains a vexing medical problem. Surgeons have few options when it comes to a long segment reconstruction of the bile duct. Biological scaffolds of decellularized biliary origin may offer an approach to support the replace of bile ducts. Our objective was to obtain an extracellular matrix scaffold derived from porcine extrahepatic bile ducts (dECM-BD) and to analyze its biological and biochemical properties. The efficiency of the tailored perfusion decellularization process was assessed through histology stainings. Results from 4'-6-diamidino-2-phenylindole (DAPI), Hematoxylin and Eosin (H&E) stainings, and deoxyribonucleic acid (DNA) quantification showed proper extracellular matrix (ECM) decellularization with an effectiveness of 98%. Immunohistochemistry results indicate an effective decrease in immunogenic marker as human leukocyte antigens (HLA-A) and Cytokeratin 7 (CK7) proteins. The ECM of the bile duct was preserved according to Masson and Herovici stainings. Data derived from scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) showed the preservation of the dECM-BD hierarchical structures. Cytotoxicity of dECM-BD was null, with cells able to infiltrate the scaffold. In this work, we standardized a decellularization method that allows one to obtain a natural bile duct scaffold with hierarchical ultrastructure preservation and adequate cytocompatibility.

Construct validity of the SurgForce system for objective assessment of laparoscopic suturing skills.

BACKGROUND: Laparoscopic surgery requires a new set of skill to be learned by the surgeons, of which the most relevant is tissue manipulation. Excessive forces applied to the tissue can cause rupture during manipulation or ischemia when confronting both sides of the tissue. The aim of this study is to establish the construct validity of the SurgForce system for objective assessment of advanced laparoscopic skills, based on the force signal generated during suture tasks, and the development of force parameters for evaluating tissue handling interaction. METHODS: The SurgForce system, a tissue handling training device that measures dynamic force, was used to capture the force generated by surgeons with different levels of laparoscopic experience. For construct validity, 37 participants were enrolled in this study: 19 medical students, 12 residents of surgical specialties and 6 expert surgeons. All participants performed an intracorporeal knotting suture task over a synthetic tissue pad with a laparoscopic box-trainer. The force performance of the participants was analyzed using 11 force-based parameters with the application of the SurgForce system. Statistical analysis was performed between novice, intermediate, and expert groups using a Kruskal-Wallis test, and between the pairs of groups using a Mann-Whitney U-test. RESULTS: Overall, 9 of the 11 force-related parameters showed significant differences between the three study groups. Results between the pairs of groups presented significant differences in 5 force parameters proposed. Construct validity results demonstrated that the SurgForce system was able to differentiate force performance between surgeons with different levels of laparoscopic experience. CONCLUSION: The SurgForce system was successfully validated. This force system showed its potential to measure the force exerted on tissue for objective assessment of tissue handling skills in suturing tasks. Furthermore, its compact design allows the use of this device in conventional laparoscopic box-trainers.

Consenso mexicano en el manejo clínico de la hidradenitis supurativa / Mexican consensus on the clinical management of hidradenitis suppurativa

Resumen ANTECEDENTES: La hidradenitis supurativa es una enfermedad inflamatoria, crónica y recurrente con gran repercusión en la calidad de vida de los pacientes, específicamente en los aspectos psicológicos y sexuales, así como también en la productividad laboral. OBJETIVO: Generar un documento de consenso sobre el manejo clínico de los pacientes con hidradenitis supurativa en México que sirva para homologar el diagnóstico y tratamiento de estos pacientes. MÉTODO: Se convocó a un grupo multidisciplinario (dermatólogos, ginecólogos, cirujanos, infectólogos, proctólogos) para analizar la evidencia en el tratamiento integral de la hidradenitis supurativa (calidad de vida, clinimetría, diagnóstico y tratamiento), localizada mediante una revisión sistemática de la bibliografía. El grupo discutió sobre los temas y se generaron las recomendaciones por acuerdo unánime de los participantes. RESULTADOS: Con frecuencia los pacientes con hidradenitis supurativa pueden tardar mucho tiempo en obtener el diagnóstico y manejo correctos, principalmente debido a la falta de evidencia sobre la enfermedad, así como a la falta de criterios para referir al paciente con un especialista. Se emitieron 22 recomendaciones para el tratamiento de pacientes con hidradenitis supurativa, que comprenden el diagnóstico, estadificación y clinimetría, así como el manejo clínico en el primer, segundo y tercer nivel de atención. CONCLUSIONES: Se emitieron las recomendaciones con base en la mejor evidencia disponible, así como la experiencia del grupo multidisciplinario de expertos en el tratamiento de hidradenitis supurativa.

Abstract BACKGROUND: Hidradenitis suppurativa is an inflammatory, chronic and recurrent disease with a high impact on patients quality of life, specifically in psychological and sexual aspects, as well as in labor productivity. OBJECTIVE: To generate a consensus document on the clinical management of patients with hidradenitis suppurativa in Mexico, that serves to standardize the diagnosis and treatment of these patients. METHOD: A multidisciplinary group was convened (dermatologists, gynecologists, surgeons, infectologists, proctologists) to analyze the evidence on the integral treatment of hidradenitis suppurativa (quality of life, clinimetry, diagnosis and treatment), located through a systematic review of the literature. The group discussed the issues and the recommendations were generated by unanimous agreement of the participants. RESULTS: Frequently, patients with hidradenitis suppurativa can take a long time to obtain the correct diagnosis and management, mainly due to the lack of evidence about the disease, as well as the lack of criteria to refer the patient to a specialist. Twenty-two recommendations were issued for the treatment of patients with hidradenitis suppurativa, which include diagnosis, staging and clinimetry, as well as clinical management in the first, second and third levels of care. CONCLUSIONS: The recommendations were issued based on the best available evidence, as well as the experience of the multidisciplinary group of experts in the treatment of hidradenitis suppurativa.

Orthogonal cameras system for tracking of laparoscopic instruments in training environments.

INTRODUCTION: Motion analysis is a valuable tool for assessment of psychomotor skills in laparoscopy. Nonetheless, it requires technologies for tracking the activity of the laparoscopic instruments during training. This paper presents a sensor-free system to track the movements of laparoscopic instruments based on an orthogonal camera system and video image processing. METHODS: The movements of the laparoscopic instruments are tracked with two webcams placed in an orthogonal configuration. The position and orientation in the three-dimensional workspace are obtained using color markers placed on the tip of the instruments. RESULTS: Accuracy tests show a resolution of 0.14 mm for displacement, with 1694 cm3 of total workspace, and 0.54° in the angular movements. Mean relative errors of the tracking system were <1%. The orthogonal cameras show high precision, linearity, and repeatability of motion recording of the laparoscopic instruments. CONCLUSION: The proposed system offers unconstrained manipulation of the instruments and a low-cost alternative for traditional tracking technologies.

INTRODUCCIÓN: El análisis del movimiento es una valiosa herramienta para la evaluación de las habilidades psicomotrices en la laparoscopia. Sin embargo, requiere tecnologías para el seguimiento de la actividad de los instrumentos laparoscópicos durante el entrenamiento. En este artículo presentamos una técnica sin sensores para realizar el seguimiento de los movimientos de los instrumentos laparoscópicos basado en un sistema de cámara ortogonal y procesamiento de imágenes de video. MÉTODO: Los movimientos de los instrumentos laparoscópicos son capturados con dos cámaras web colocadas en configuración ortogonal. La posición y la orientación en el espacio de trabajo tridimensional se obtienen utilizando marcadores de color colocados en la punta de los instrumentos. RESULTADOS: Las pruebas de precisión mostraron una resolución de 0.14 mm para el desplazamiento, con 1694 cm3 de espacio de trabajo total y 0.54° en los movimientos angulares. Los errores relativos medios del sistema de seguimiento fueron <1%. Las cámaras ortogonales demostraron alta precisión, linealidad y repetibilidad de la captura de movimiento de los instrumentos laparoscópicos. CONCLUSIONES: El sistema propuesto ofrece una manipulación sin restricciones de los instrumentos laparoscópicos y una alternativa de bajo costo para las tecnologías tradicionales de captura de movimiento.

[A current perspective of natural orifices transluminal endoscopic surgery (NOTES)]. / Perspectiva actual de la cirugía endoscópica transluminal por orificios naturales (CETON).

Natural orifice transluminal endoscopic surgery (NOTES) represents an alternative in surgical approach, combined with the progress and experience gained from conventional and endoscopic surgery. Bibliographic research in PubMed, Medline database from 2000 to 2015 and analysis of the literature reviews found. NOTES provides vision and natural orifice approach, it has optimized operating times as well as reduced complications and better cosmetic results. Small series of patients have been reported, but there is not a valid clinical multicenter study by evidence-based medicine. NOTES can help to improve the standard operations, complemented with laparoscopic surgery rather than replace it and thus develop tools for the resolution of various diseases that require surgical treatment. This option in current surgery is safe and presents satisfactory results in the reported cases. The development of this new approach of performing surgical procedures requires further study and development of new technology in order to increase the accessibility of these procedures and represent in a practical and sustained way, a better option to approach surgical pathology.

[The importance of master's degree and doctorate degree in general surgery]. / Importancia de la maestría y el doctorado en cirugía general.

BACKGROUND: The Doctor of Philosophy is the highest academic degree that can be obtained in universities. Graduate Education Program in Medicine in Mexico is divided into 2 major categories: Medical Specialty and Master studies/Doctor of Philosophy. The objective of this study was to demonstrate the importance of master's degrees and Doctor of Philosophy in general surgery. MATERIAL AND METHODS: A literature search in PubMed and Medline among others, from 1970 to 2015 with subsequent analysis of the literature reviews found. DISCUSSION: The physicians who conducted doctoral studies stand out as leaders in research, teaching and academic activities. Dual training with a doctorate medical specialty is a significant predictor for active participation in research projects within the best educational institutions. RESULTS: It is important to study a PhD in the education of doctors specialising in surgery, who show more training in teaching, research and development of academic activities. Currently, although there is a little proportion of students who do not finish the doctoral program, the ones who do are expected to play an important role in the future of medical scientific staff. It has been shown that most doctors with Doctor of Philosophy have wide range of career options. CONCLUSION: The importance of doctoral studies in the formation of general surgery is due to various reasons; the main one being comprehensively training physician scientists who can develop in clinical, teaching and research.

Histological Analysis of Intra-Abdominal Adhesions Treated with Sodium Hyaluronate and Carboxymethylcellulose Gel.

PURPOSE: To evaluate macro and microscopically the adhesions developed after using the anti-adherence compound sodium hyaluronate and carboxymethylcellulose (SH-CBMC) gel and to determine the volume of the adhesions using a stereological estimation. METHODS: The study was experimental, random, comparative, and prospective. The subjects of the study were male Wistar rats divided in three groups (n = 10). Group I (control) included rats with no peritoneal injury. Group II rats had a 2 cm diameter injury created bilaterally in the parietal peritoneum at 3 cm from the abdominal midline with electrocautery coated with physiological solution. Group III rats were given the same injuries and coated with SH-CBMC gel. All groups were followed up postoperatively for 30 days, after which a laparotomy was performed to macroscopically determine the presence and type of adhesions. Experimental models were euthanized with anesthetic overdose and biopsies were taken for histopathological examination and stereological estimate of the volume of adhesions. RESULTS: Macroscopic adhesions were 20% less prevalent in Group III compared to Group II, which presented 40% more multiple and firm adhesions, unlike in Group III, in which they were unique and lax. There was a statistically significant decrease in the presence and number of adhesions in rats treated with SH-CBMC gel. Inflammatory infiltrate was significantly lower in rats treated with SH-CBMC gel, but there were no differences in connective tissue, fibrosis, and angiogenesis among groups. There was no statistical difference in the overall volume of adhesions among the treatment groups. CONCLUSIONS: SH-CBMC gel reduces macroscopic presence and number of adhesions and the severity of the inflammatory infiltrate.

Absorbable bioprosthesis for the treatment of bile duct injury in an experimental model.

INTRODUCTION: Cholecystectomy is a common surgical procedure in which complications may occur, such as injury to the biliary tract, which are associated with high morbidity. The aim of this study was to demonstrate the efficacy of a polymer-based absorbable bioprosthesis with bone scaffold for the treatment of bile duct injury in an animal model. MATERIALS AND METHODS: An absorbable bioprosthesis was used to replace the common bile duct in 15 pigs which were divided into 3 groups with different follow-ups at 1, 3 and 6 months. The animals were anesthetized at these time points and laboratory tests, Magnetic Resonance Cholangiopancreatogram [MRCP], Choledochoscopy using Spyglass and Endoscopic retrograde Cholangiopancreatogram [ERCP] were performed. After radiological evaluation was complete, the animals were euthanized and histological and immunohistochemical analyses were performed. RESULTS: Liver function tests at different time points demonstrated no significant changes. No mortality or postoperative complications were found in any of the experimental models. Imaging studies ([MRCP], [ERCP] and Choledochoscopy with SpyGlass(™)) showed absence of stenosis or obstruction in all the experimental models. DISCUSSION: Histological and immunohistochemical staining (CK19 and MUC5+) revealed the presence of biliary epithelium with intramural biliary glands in all the experimental models. There was no stenosis or obstruction in the bile duct. CONCLUSIONS: The bioprosthesis served as scaffolding for tissue regeneration. There was no postoperative complication at 6 months follow-up. This bioprosthesis could be used to replace the bile duct in cancer or bile duct injury. The bioprosthesis may allow different modeling depending on the type of bile duct injury.

Simulador para la resección de un lipoma superficial / Simulator for resection of superficial lipoma

Resumen Introducción: La educación quirúrgica actual exige estrategias educativas modernas que fomenten en el alumno el deseo de buscar información, procesarla y hacer uso de ella en el momento que se requiera, integrando aspectos teóricos y prácticos, que les sean útiles para su vida profesional. Objetivo: Diseñar un modelo de resección de lipoma superficial que permita al alumno desarrollar sus habilidades quirúrgicas en un simulador con características únicas, ya que ofrece una gran similitud con la realidad, ejemplo de ello es el sangrado activo. Los materiales para la preparación son de bajo costo y accesibles, lo cual permite su reproducción las veces que sean necesarias para adquirir la habilidad quirúrgica básica. Conclusiones: Consideramos que el simulador cuenta con características especiales que lo hacen una opción educativa práctica, de bajo costo y de fácil reproducción.

Abstract Introduction: The current surgical education requires modern educational strategies that encourage the students' desire to seek information, process and make use of it at the time required integrating theory and practice that are useful for your life profession. Objective: was to design a lipoma resection model that allows students to develop their surgical skills in a simulator with unique characteristics as it offers a great similarity with reality example is active bleeding. The preparation materials are inexpensive and accessible allowing playback as often as necessary to acquire basic surgical skills. Conclusions: We believe that the simulator has special features that make it a practical educational choice, inexpensive and easy to reproduce.

Bases moleculares de la sepsis / Molecular basis of sepsis

Resumen La sepsis es un síndrome que continúa siendo una causa importante de morbilidad y mortalidad entre los pacientes críticamente enfermos. Pese al desarrollo de la investigación básica dedicada al tema y los numerosos ensayos clínicos, no se han logrado avances notables en el desarrollo de terapias vanguardistas y eficaces para su manejo. Los trastornos fisiológicos inducidos por la sepsis son en gran parte debidos a la respuesta del huésped a los microorganismos invasores en contraste con los efectos directos del propio microorganismo. La sepsis, entendida como la respuesta inflamatoria sistémica a la infección, está marcada por la producción desregulada de citocinas proinflamatorias. Estos mediadores conducen de manera colectiva a la insuficiencia orgánica múltiple, y en última instancia, a la muerte. Es en este sentido que el papel de la inflamación en la fisiopatogenia de la sepsis, aunque todavía no entendida completamente, resulta claramente crítico. Esta revisión proporciona una perspectiva de las diversas interacciones moleculares que ocurren durante la sepsis, con el intento de poder comprender la naturaleza de la respuesta desregulada del sistema inmunitario durante ésta.

Abstract Sepsis continues to be a primary cause of high mortality and morbidity in critically ill patients. Despite constant growth in dedicated basic investigation and numerous clinical studies, no remarkable developments have been made for effective and innovative therapies. The physiologic disorders induced by sepsis are primarily due to the overwhelming immune response to invading pathogens rather than the direct effects caused by the pathogen. Sepsis, understood as the systemic inflammatory response to infection is characterized by the unregulated production of proinflammatory cytokines. These mediators collectively lead to multiple organ failure and eventually to death. In this context, the role of inflammation in the physiopathology of sepsis, though not fully understood, is of critical importance. This review provides a perspective of the most current understandings of the molecular mechanisms during sepsis, which may provide an attempt to understand the nature of this unregulated response of the immune systems during sepsis.

Modelo biológico no vivo para la enseñanza de la técnica de venodisección en alumnos de pregrado de la carrera de medicina / Non-live biological model for the teaching of the venous cutdown technique to undergraduate medical students

Objetivo: Proporcionar material didáctico útil al estudiante y al médico general para conocer la técnica de venodisección en un modelo biológico no vivo. Sede: Departamento de Cirugía, Facultad de Medicina, UNAM. Diseño: Modelo de enseñanza. Material y método: Se proporcionan indicaciones, contraindicaciones, características anatómicas y técnica a considerar. Empleamos pata de cerdo como modelo didáctico por ser accesible en costos, disponibilidad y un modelo fácilmente reproducible por los alumnos. Por su semejanza con los eventos clínicos que suceden en los pacientes a nivel hospitalario, consideramos que representa un buen método de enseñanza de habilidades quirúrgicas en el pregrado. Conclusión: El actual modelo biológico es una opción viable y representativa de la venodisección; el alumno aprende a identificar al paciente que requiere de este procedimiento; una vez identificado, podrá realizar el procedimiento de manera adecuada evitando, en la medida de lo posible, cualquier tipo de complicación.

Objective: To provide teaching material useful for the medical student and the general physician to learn the venous cutdown technique in a non-live biological model. Setting: Department of Surgery, School of Medicine, UNAM. Design: Teaching model. Material and method: Indications, contraindication, anatomical characteristics and technique to be considered will be provided. We use a pig foot as didactic model because it is accessible in terms of costs, availability, and can be reproduced easily by students. Due to its similarity with clinical events occurring in patients at the hospital level, we consider that it represents a good teaching method of surgical skills at the undergraduate level. Conclusion: The current biological model is a viable option and representative of venous cutdown. The student learns to identify the patient that requires this procedure, once identified he will be able to perform the procedure adequately avoiding, as much as possible, any type of complication.