Postoperative outcomes of minimally invasive adrenalectomy: do body mass index and tumor size matter? A single-center experience.

BACKGROUND: Since Gagner performed the first laparoscopic adrenalectomy in 1992, laparoscopy has become the gold-standard procedure in the treatment of adrenal surgical diseases. A review of the literature indicates that the rate of intra- and postoperative complications are not negligible. This study aims to describe the single-center experience of adrenalectomies; and explore the associations between body mass index (BMI) and tumor volume in main postoperative outcomes. METHODS: Retrospective observational study with a prospective database in which we described patients who underwent adrenalectomy between January 2015 and December 2020. Operative time, intraoperative blood loss, conversion rate, complications, length of hospital stay, and comparison of the number of antihypertensive drugs used before and after surgery were analyzed. Analysis of BMI and tumor volume with postoperative outcomes such as anti-hypertensive change (AHC) in drug usage and pre-operative conditions were performed. RESULTS: Forty-five adrenalectomies were performed, and all of them were carried out laparoscopically. Four were performed as a robot-assisted laparoscopy approach. Nineteen were women and 26 were men. Mean age was 54.9 ± 13.8 years. Mean tumor volume was 95.698 mm3 (3.75-1010.87). Mean operative time was shorter in right tumors (2.64 ± 0.75 h) than in left tumors (3.33 ± 2.73 h). Pearson correlation was performed to assess the relationship between BMI and AHC showing a direct relationship between increased BMI and higher change in anti-hypertensive drug usage at postoperative period r(45) = 0.92, p > 0.05 CI 95%. Higher tumor volume showed a longer operative time, r(45) = 0.6 (p = 0.000 CI 95%). CONCLUSIONS: Obese patients could have an increased impact with surgery with an increased change in postoperative anti-hypertensive management. Tumor volume is associated with increased operative time and blood loss, our data suggest that it could be associated with increased rates of morbidity. However, further prospective studies with larger sample sizes are needed to validate our results.

Association between clinical and surgical variables with postoperative outcomes in patients treated for intestinal obstruction for non-malignant conditions: a cross-sectional study.

Intestinal obstruction is considered a frequent surgical pathology related to previous surgical procedures. Many different factors can lead to different outcomes when surgical management is needed. Therefore, we aim to describe the factors related to morbidity and mortality in surgical management of IO in a single-center experience. Retrospective observational study with a prospective database, in which we described patients who underwent surgical management due to intestinal obstruction between 2004 and 2015. Demographics, perioperative data, surgical outcomes, morbidity, and mortality were described. 366 patients were included. Female were 54.6%. Mean age was 61.26. Laparoscopic approach was done in 21.8% and the conversion rate was 17.2%. Intestinal resection was performed in 37.9% of the cases. Postoperative complications were observed in 18.85%. Reintervention and mortality were 9.5% and 4.1% respectively. Laparoscopic approach shows lesser time of intestinal transit (mean 28.67 vs. mean 41.95 h), and restart of oral intake after surgery (mean 96.06 vs. mean 119.65) compared with open approach. Increased heart rate and intensive care unit length of stay were related with mortality (p 0.01 and 0.000 respectively). For morbidity, laparotomy and need and duration of ICU stay were related with any complication statistically significant (p 0.02, 0.008, 0.000 respectively). Patients with increased heart rate in the emergency room, decreased amount of intravenous fluids, need and higher length of stay in the intensive care unit, and delay in resuming oral intake after surgery appear to have poor outcomes. Laparoscopic approach seems to be a safe and feasible approach for intestinal obstruction in selected patients.

Outcomes of 207 totally extraperitoneal hernia repairs using self-fixation mesh.

Inguinal hernia (IH) repair is one of the most common procedures in general surgery around the world. Minimizing postoperative acute and chronic pain without increasing recurrence has been a critical point, giving place to different strategies like self-fixation mesh. The current study aimed to describe a group of patients who underwent IH repair by Totally Extraperitoneal (TEP) technique with self-gripping mesh at a fourth level hospital between 2012 and 2019. Retrospective review of a prospectively collected database including patients who underwent laparoscopic TEP approach with self-fixation mesh for IH repair. Follow up data was obtained at 12, 24, 36, 48, and 60 months post surgical intervention. 207 hernia repairs were performed in 142 patients, with a total of 66 patients with bilateral IH. 10.6% required hospitalization due to either concomitant procedure performed or cardiovascular comorbidities, with a mean hospital stay of 1.6 days. Median and late follow up was up to 5 years. 88.9% of patients complete a year, 86% two years, and 36.7% with a 5 year follow-up. IH repair using the TEP technique and self-fixation mesh showed to be an excellent approach, demonstrating satisfactory results in follow up and complications.

Histological analysis of an alkaline based tissue clearing technique for fetal musculoskeletal tissue / Análisis histológico de una técnica de limpieza de tejido de base alcalina para tejido musculoesquelético fetal

SUMMARY: Tissue clearing techniques are frequently used in the observation and description of anatomical structures and pathways without altering the three-dimensional layout of the anatomical specimen. Tissue optical clearing promotes preservation of three-dimensional structures, which allows the study of the internal anatomy in its original position and original spatial interaction. Among these techniques, Potassium Hydroxide (KOH) maceration clearing is one of the most widely used. However, the histological changes of tissue after KOH maceration have yet to be fully understood. Our aim is to describe the microscopical differences between macerated and normal tissue. To better understand said changes, two human fetuses with a gestation period of 16 to 28 weeks were cleared and processed for histological analysis. Microtome slides of the fetuses' lower limbs were obtained and stained with Hematoxylin & Eosin, Periodic Acid Schiff (PAS), and Masson's trichrome with the purpose of observing the histological and macromolecule composition changes in cleared tissue. Remarkable differences at a histological level regarding the composition of the cellular structures, since diaphanized tissues showed a predominance of extracellular matrix composed of collagen fibers with the absence of most of the nucleated cellular tissue. Phospholipid's saponification, nucleic acids degradation and a change on proteins structural properties are the main factors inducing clearing. At the same time, molecular stability of collagen in alkaline conditions allows the specimen to maintain its shape after the process.

RESUMEN: Las técnicas de limpieza de tejido se utilizan con frecuencia en la observación y descripción de estructuras y vías anatómicas sin alterar el diseño tridimensional de la muestra anatómica. El aclaramiento óptico de tejidos promueve la preservación de estructuras tridimensionales, lo que permite el estudio de la anatomía interna en su posición original y la interacción espacial original. Entre estas técnicas, el aclarado por maceración con Hidróxido de Potasio (KOH) es una de las más utilizadas. Sin embargo, los cambios histológicos del tejido después de la maceración con KOH aún no se han entendido por completo. Nuestro objetivo es describir las diferencias microscópicas entre el tejido macerado y el normal. Para entender mejor dichos cambios, dos fetos humanos con un período de gestación de 16 a 28 semanas fueron aclarados y procesados para análisis histológicos. Se obtuvieron microtomos de las extremidades inferiores de los fetos y se tiñeron con hematoxilina y eosina, ácido peryódico de Schiff (PAS) y tricrómico de Masson con el fin de observar los cambios histológicos y de composición de macromoléculas en el tejido aclarado. Diferencias notables a nivel histológico en cuanto a la composición de las estructuras celulares, ya que los tejidos diafanizados mostraban un predominio de matriz extracelular compuesta por fibras de colágeno con ausencia de la mayor parte del tejido celular nucleado. La saponificación de los fosfolípidos, la degradación de los ácidos nucleicos y un cambio en las propiedades estructurales de las proteínas son los principales factores que inducen la depuración. Al mismo tiempo, la estabilidad molecular del colágeno en condiciones alcalinas permite que la muestra mantenga su forma después del proceso.

An alternative method for the comparative study of coronary vessels: repletion and diaphanization experience in seven animal models / Repleción y diafanización como una alternativa para el estudio comparativo de los vasos coronarios: experiencia en siete modelos animales

Coronary arteries establish a complex blood vessel system, right and left coronary arteries commonly originate from the aortic sinuses and divide into multiple branches that supply the heart with several important variations between species. Diaphanization is a preservative technique which allows internal structures visualization, maintaining the three-dimensionality of the specimen. In this study, human (Homo sapiens), goat (Capra aegagrus hircus), bovine (Bos Taurus), equine (Equus caballus), porcine (Sus scrofa domesticus), canine (Canis lupus familiaris) and feline (Felis silvestris catus) coronary arteries were injected with selfcuring methyl-methacrylate and posteriorly diaphanized. The coronary vasculature was adequately observed in all models while keeping the three-dimensional relation with surrounding cardiac structures, except for septal arteries which were not visualized. As incidental findings, anatomical variations in canine and human hearts were observed. Repletion-diaphanization is a useful blended method to visualize the morphology of superficial coronary arteries. It could be a valuable tool in anatomical teaching and research, but further research needs to be done to prove its effectiveness in different vessel systems.

Las arterias coronarias son un complejo de vasos sanguíneos que usualmente se originan en los senos aórticos y que al dividirse en múltiples ramas suplen los requerimientos metabólicos del tejido cardiaco; cabe aclarar que la anatomía de estas estructuras posee variaciones importantes entre especies. La diafanización es una técnica de preservación que permite observar estructuras internas de un espécimen sin dañar su tridimensionalidad. En este estudio las arterias coronarias del corazón humano (Homo sapiens), caprino (Capra aegagrus hircus), bovino (Bos Taurus), equino (Equus caballus), porcino (Sus scrofa domesticus), canino (Canis lupus familiaris) y felino (Felis silvestris catus), fueron repletadas con metil-metacrilato y posteriormente diafanizados. Se observa la irrigación coronaria de cada uno de los corazones y su relación con las demás estructuras cardiacas, exceptuando las arterias septales. Como hallazgos incidentales se observaron variaciones anatómicas en los corazones canino y humano. Finalmente, esta técnica resultó de utilidad para evaluar la anatomía coronaria, lo que puede ser valioso para educación e investigación. Posteriores investigaciones deben ser realizadas para probar su utilidad en otros sistemas vasculares.

Diaphanization: a standardized protocol for non-fetal tissue preservation / Diafanización: un protocolo estandarizado para la preservación de tejido adulto

In response to the arising difficulty of dissection use during anatomy courses, medical schools have been forced to research alternative teaching methods. These are meant to help students develop three dimensional mental images of the human body and increase spatial reasoning, thus improving the learning process of human morphology. One of those methods, used at the Universidad de los Andes is the Diaphanization process. This technique is a well-known method for specimen preservation, used as an anatomy research and teaching tool. Even though it is frequently used, finding a standardized protocol in indexed journals is not possible, which hinders the use of the technique. The standardization of an updated protocol is a need in order to continue exploiting the maximum educational capacity of the specimens used during classwork. The process used at the Universidad de los Andes for non-fetal tissue preservation by Diaphanization is described, with a detailed explanation of its five main stages: Injection, Fixation, Dehydration, Bleaching (or Maceration) and Final preservation. The final result should be an organ preserved in an acrylic box which allows clear three dimensional visualization of anatomical structures that can be used for the study and description of general anatomy and vascular structure. It also helps with spatial reasoning and represents little to no biological risk, leading to a new level of anatomical teaching and experimenting. Several specimens obtained at our laboratory through this technique are presented.

Como respuesta a la dificultad del uso de disección como una herramienta en el curso de anatomía, las escuelas de medicina se han visto forzadas a investigar y desarrollar métodos alternativos que la reemplacen. Estos pretenden estimular el desarrollo de la percepción tridimensional de los estudiantes, logrando mejor racionamiento espacial, y así, mejorando el proceso de aprendizaje de la morfología humana. Uno de estos métodos, en uso en la Universidad de los Andes, es el proceso de diafanización. Esta técnica es ampliamente conocida en el ámbito de preservación de tejidos, y empleada en investigación y educación. Aún con su uso frecuente, un protocolo estandarizado que la describa no está disponible en la literatura indexada, lo cual limita su uso. La estandarización de un protocolo actualizado es necesaria para permitir el continuo uso de esta técnica. Se describe el proceso de preservación de tejido adulto mediante la diafanización, con una explicación detallada de los 5 pasos que la componen: Inyección, Fijación, Deshidratación, Macerado y Preservación final. El resultado es un órgano inmerso en glicerina en un contenedor de acrílico que permite una visualización tridimensional de las estructuras anatómicas del espécimen, que puede ser empleado por los estudiantes para su estudio, y permite una descripción de la anatomía general del modelo y su estructura vascular. Adicionalmente incrementa el razonamiento espacial de los estudiantes, y no presenta ningún riesgo biológico. Se presentan una variedad de especímenes de características particulares obtenidos mediante la aplicación de esta técnica.

Corrosion casting, a known technique for the study and teaching of vascular and duct structure in anatomy / Inyección corrosión, una técnica conocida para el estudio y enseñanza de ductos y estructuras vasculares en anatomía

Teaching and learning anatomy, as a process, has changed. Fresh cadavers were once used as a tool for the student to approach the human body in order to overcome theoretical knowledge and gain applied expertise. Today, techniques such as corrosion casting are known to be a more effective way of achieving optimal results with the students. This paper examines a method to apply this technique to an organ using different polymers. The concentrations for acrylic, epoxy resin, polyester resin, and room temperature vulcanization (RTV) silicone are described, as well as the corresponding diameter of the duct to be injected with each one. A variety of specimens obtained using this technique, their qualities and characteristics are presented. The results of using these procedures while involving the students, showed increased sense of responsibility, dedication and awareness, which led them to take the class more seriously and enjoy the process of learning. Additionally, the specimens left by the students will help future classes reduce the number of specimens needed.

El proceso de aprendizaje y enseñanza en anatomía ha cambiado recientemente, el cadáver fue la primera herramienta que permitía al estudiante una aproximación practica al cuerpo humano, facilitando que este se sobrepusiera al conocimiento teórico adquirido en el aula, y desarrollara experticia aplicada. Hoy en día, técnicas como la inyección corrosión son conocidas por lograr mejores resultados con los estudiantes. Este trabajo presenta un método para aplicar esta técnica a un órgano, mediante el uso de diferentes polímeros. Las concentraciones adecuadas de acrílico, resina epoxica, resina poliéster, y silicona RTV (room temperature vulcanization) son descritas, así como el diámetro sugerido para el uso de cada polímero. Se presenta una variedad de especímenes obtenidos mediante esta técnica, así como sus cualidades y características. Al integrar a los estudiantes en el proceso de creación de los especímenes, estos demuestran mayor sentido de responsabilidad, dedicación y autoconciencia, generando mayor compromiso, y entusiasmo con la clase y el proceso de aprendizaje. Adicionalmente, los especímenes producidos por ellos, serán de gran utilidad para clases a futuro.

Morphometric study of five constant skull base foramina in the Muisca population of the Tibanica anthropological collection of the Universidad de Los Andes / Estudio morfométrico de cinco forámenes constantes de la base del cráneo en la población Muisca de la colección antropológica Tibanica de la Universidad de Los Andes

Among osteological anatomic variations are those of the skull base foramina. These openings have conventionally been classified as either constant or variant. Their presence and dimensions have been associated with certain pathologies and procedural complications. Additionally, variability in these foramina between different ethnic groups has been observed, and it is sometimes possible to identify particular patterns of variability in certain populations. This anthropometric cross-sectional study seeks to determine the principal dimensions (bilateral anteroposterior and lateromedial diameters) of five constant skull base foramina in the adult Muisca population of the Tibanica anthropological collection at Universidad de los Andes. The studied foramina were magnum, jugular, ovale, spinosum, and external opening of the carotid canal. Only dimensions of the external openings of the foramina were recorded, owing to the preservation state of the skulls in the collection. The mean left and right anteroposterior and lateromedial diameters were 3.48 mm, 6.16 mm and 3.25 mm, 6.26 mm for the foramen ovale; 2.38 mm, 2.65 mm and 2.39 mm, 2.66 mm for foramen spinosum; 8.36 mm, 15.41 mm and 8.55 mm, 15.10 mm for the jugular foramen; 5.28 mm, 6.75 mm and 5.48 mm, 6.97 mm for the external opening of the carotid canal; and 33.90 mm, 29.47 mm for the foramen magnum. All foramina were measured twice, no important differences were observed between the results obtained in the first and second measurements. The skull base foramina of the sample studied did not suggest high variability within the population regarding these characteristics. Moreover, we can state that the morphometric profile displayed by the Tibanica collection at Universidad de los Andes is different from the one observed in other populations. Additional studies of anatomic variations in indigenous populations may be needed to make possible similarities and/or differences and their causes evident.

Entre las variaciones anatómicas óseas, se consideran aquellas referentes a los forámenes de la base del cráneo. Convencionalmente, estos orificios han sido clasificados como variantes o constantes. Su presencia y dimensiones se asocian a ciertas patologías y complicaciones procedimentales. Adicionalmente, se ha observado variabilidad en estos entre distintos grupos étnicos y en algunas ocasiones es posible identificar patrones particulares en poblaciones específicas. Este estudio morfométrico de corte transversal busca determinar las dimensiones principales (diámetros anteroposterior y lateromedial) de cinco forámenes constantes de la base del cráneo en la población adulta Muisca de la colección antropológica Tibanica de la Universidad de los Andes. Los forámenes estudiados fueron: magno, yugular, ovale, espinoso y la apertura externa del canal carotideo. Debido al estado de preservación de los cráneos, se registraron las dimensiones de las aperturas externas de los forámenes. La media de los diámetros izquierdo y derecho anteroposterior y lateromedial fue 3,48 mm, 6,16 mm y 3,25 mm, 6,26 mm para el foramen ovale; 2,38 mm, 2,65 mm y 2,39 mm, 2,66 mm para el espinoso; 8,36 mm, 15,41 mm y 8,55 mm, 15,10 mm para el yugular; 5,28 mm, 6,75 mm y 5,48 mm, 6,97 mm para la apertura externa del canal carotideo; y 33,90 mm, 29,47 mm para el foramen magno. Todos los diámetros se registraron dos veces, no se observó ninguna diferencia importante entre los registros de la primera y segunda medición. En general, las dimensiones de los forámenes estudiados no varían mucho en la colección ósea Muisca de Tibanica. En cuanto a estas características anatómicas, la población utilizada es diferente con respecto a algunas modernas. Por otro lado, se requieren investigaciones adicionales de este tipo con el fin de evidenciar posibles similitudes y diferencias entre poblaciones (prehispánicas y modernas) y determinar sus causas.