Luis Miguel Marín Gómez

Application of new technologies to the teaching of surgery in the school of medicine

Abstract Introduction The new methods of teaching, based on new technologies, already available in other educational and professional fields are gradually being introduced in our medical schools. The aim of our study is to present our initial experience in the introduction of a subject on the principles of surgery in our university. Material and methods The subject was offered voluntary to undergraduate students, with a maximum of 65 students per course during 2 consecutive academic years, while maintaining the traditional teaching with a formal lecture program with a different lecturer. The subject was designed with 60% virtuality on a WebCT platform and later in Moodle. The virtual subject was structured into teaching units, academically directed activities, and communication tools. The subject was assessed in a report prepared by Cadiz University Department of Evaluation and Quality. Results There were 32 students in the 2005-2006 course and 62 in the following course. The mean activity of the students was: 602 accesses, 13 subjects for discussion forums, and 20 e-mails between students and teachers. The students who participated in the virtual subject have remarked that virtualisation make it more attractive and is an aid in the acquisition of knowledge. The data obtained from the report showed better results than the mean obtained in other subjects of the Department, School of Medicine and Cadiz University. Conclusions The virtual subject of principles of surgery has been well evaluated in our university campus. We believe that the provision of teaching tools and new communication models make an effective contribution to the teaching of surgery as a subject in the school of medicine curriculum.

Translational pancreatic cancer research: A comparative study on patient-derived xenograft models

AIM To assess the viability of orthotopic and heterotopic patient-derived pancreatic cancer xenografts implanted into nude mice. METHODS This study presents a prospective experimental analytical follow-up of the development of tumours in mice upon implantation of human pancreatic adenocarcinoma samples. Specimens were obtained surgically from patients with a pathological diagnosis of pancreatic adenocarcinoma. Tumour samples from pancreatic cancer patients were transplanted into nude mice in three different locations (intraperitoneal, subcutaneous and pancreatic). Histological analysis (haematoxylin-eosin and Masson’s trichrome staining) and immunohistochemical assessment of apoptosis (TUNEL), proliferation (Ki-67), angiogenesis (CD31) and fibrogenesis (α-SMA) were performed. When a tumour xenograft reached the target size, it was re-implanted in a new nude mouse. Three sequential tumour xenograft generations were generated (F1, F2 and F3). RESULTS The overall tumour engraftment rate was 61.1%. The subcutaneous model was most effective in terms of tissue growth (69.9%), followed by intraperitoneal (57.6%) and pancreatic (55%) models. Tumour development was faster in the subcutaneous model (17.7 ± 2.6 wk) compared with the pancreatic (23.1 ± 2.3 wk) and intraperitoneal (25.0 ± 2.7 wk) models (P = 0.064). There was a progressive increase in the tumour engraftment rate over successive generations for all three models (F1 28.1% vs F2 71.4% vs F3 80.9%, P < 0.001). There were no significant differences in tumour xenograft differentiation and cell proliferation between human samples and the three experimental models among the sequential generations of tumour xenografts. However, a progressive decrease in fibrosis, fibrogenesis, tumour vascularisation and apoptosis was observed in the three experimental models compared with the human samples. All three pancreatic patient-derived xenograft models presented similar histological and immunohistochemical characteristics. CONCLUSION In our experience, the faster development and greatest number of viable xenografts could make the subcutaneous model the best option for experimentation in pancreatic cancer.

Incidencia y supervivencia de los tumores de novo en el trasplante hepático

INTRODUCTION The greater survival of transplanted patients is accompanied by an increase in the rate of de novo malignancies (NM), which are the most frequent late-onset complication. We can distinguish between non-melanoma skin cancers (NMSC), post-transplant lymphoproliferative disorders (PTLD) and solid organ cancers (SOC). Our objective is to determine the incidence of the different types of NM, the time elapsed until diagnosis and survival rates in our setting. METHODS We conducted a retrospective study of 1071 liver transplant patients from 1990 to 2015 at our center. We analyzed the demographic variables, incidence of NM and survival. RESULTS 184 NM developed in 1071 transplant patients (17%), specifically 19% of the males and 13% of the females (P=.004). The most frequent NM were NMSC (29%), lung (18%), head and neck (16%), PTLD (10%) and gastrointestinal (8%). The median time of diagnosis was 7.9 years in NMSC, 3.9 years in PTLD and 9.8 years in SOC. Patients with NMSC had significantly better survival than those with PTLD or SOC. The incidence of de novo tumors (excluding NMSC) was 1889/100,000 transplants/year. By gender, lung cancer was the most common TOS in men and breast cancer in women. CONCLUSION In our setting, excluding NMSC, the incidence is 8.8 times greater than estimations for the general population, with a high rate of lung cancer, so we should implement preventive and diagnostic strategies.

Reconstrucción de la arteria hepática derecha aberrante en la duodeno-pancreatectomía cefálica ☆

Hepatic arterial vascularization presents great anatomic variability. The vascular configuration described as normal is found in only 55%–75.5% of cases, which means that a large percentage of patients present an anatomic variation. Amongst them, the most frequent variation is the right hepatic artery (RHA), branch of the superior mesenteric artery (SMA). This variation can involve a single right hepatic artery, called ‘‘aberrant’’, that originates in the SMA; instead, there may be 2 coexisting right hepatic arteries (one branch originating in the SMA, called ‘‘accessory’’, and another of the proper hepatic artery). The importance of the presence of a variant hepatic artery in pancreatic surgery has been commented in several publications. An RHA that irrigates in the SMA has a close relationship with the head of the pancreas since its course is adjacent and occasionally passes through its parenchyma. Due to this disposition, it is susceptible to being infiltrated by tumors of the pancreatic head. Furthermore, the absence of collateral vascularization and the inadvertent sectioning of an RHA branch of the SMA during a pancreaticoduodenectomy (PD) can lead to ischemia and necrosis of the right liver lobe. Finally, once the gastroduodenal artery is dissected, the RHA branch of the SMA becomes the main source of vascularization of the distal common bile duct. We present a case of distal cholangiocarcinoma with infiltration of an aberrant RHA (ARHA) that was satisfactorily resolved with arterial reconstruction without the use of vascular stents. The patient is a 54-year-old woman who had been studied for obstructive jaundice and treated with percutaneous transhepatic cholangiography. CT angiography demonstrated a tumor that was obstructing the distal common bile duct and detected the infiltration of an ARHA. No liver metastases or infiltration of the SMA were observed. These findings indicated the need for a PD (Figs. 1 and 2). To identify the RHA branch of the SMA, we carefully dissected the hepatoduodenal ligament after having palpated the free edge of the ligament, which confirmed the presence of arterial pulse. Using an extended Kocher maneuver, we observed the SMA at its origin and confirmed the absence of tumor infiltration. In the same manner, we carefully dissected the common bile duct to decrease the risk of inadvertently ligating the RHA branch of the SMA, which in this area is located postero-lateral to the common hepatic duct. As part of the lymph node dissection, skeletization of the portal vein and common hepatic artery was performed. ARHA was confirmed as there was no right hepatic artery stemming from the proper hepatic artery. In cases of infiltration by the tumor mass, as seen in our patient, or in those with an intrapancreatic pathway, the artery should be sacrificed with the PD surgical specimen and later reconstructed. We used vascular micro-bulldog clamps on the common hepatic artery, proper hepatic artery and the ARHA to dissect the gastroduodenal artery (GDA), while preserving as much of its length as possible. In our case, we obtained 15 mm up until the bifurcation of the superior pancreaticoduodenal arteries. Afterwards, we dissected the isthmus and confirmed the inclusion of the ARHA branch of the SMA in the tumor mass.

Diverticulitis por divertículo de Meckel gigante con fecalito en su interior

or infraumbilical de varios dı́as de evolución, rectorragia ocasional y febrı́cula. Exploración: pogastrio, con irritación peritoneal. Tacto rectal, negativo. Analı́tica: elevación de reactantes de fase aguda. Tomografı́a computarizada abdominal (fig. 1): imagen de burbuja aérea en hipogastrio con nivel hidroaéreo y cuerpo extraño en su interior. En la laparoscopia exploradora se observa un divertı́culo gigante en el ı́leon distal con datos de inflamación aguda (fig. 2), que resecamos mediante grapadora mecánica. El postoperatorio transcurrió sin complicaciones.

Estudio del aclaramiento bacteriano en el trasplante esplénico cervical en ratas

Resumen Introduccion El objetivo de nuestro trabajo es estudiar el aclaramiento bacteriano en el trasplante esplenico cervical en ratas segun nuestro modelo experimental. Material y metodo Distribucion aleatoria de 100 ratas isogenicas tipo Lewis en 4 grupos: grupo control con laparotomia y preservacion del bazo, grupo de esplenectomia, grupo de autotrasplante esplenico y grupo de trasplante esplenico heterotopico vascularizado en la region cervical. Se realizo un estudio del aclaramiento bacteriano mediante la determinacion del numero de colonias/ml de sangre tras infeccion por neumococos en una dosis de 1 × 107. Resultados El grupo de trasplante esplenico presenta un efecto protector frente a la bacteriemia superior al de autotrasplante y esplenectomia; aunque inferior al de control. Estas diferencias son estadisticamente significativas (p Conclusiones Nuestro modelo experimental de trasplante esplenico cervical en ratas consigue, en el aclaramiento bacteriano, valores proximos a la normalidad y superiores a los del autotrasplante esplenico.

Cervicotomía lateral como abordaje selectivo del tiroides

Resumen Introduccion Los objetivos de este trabajo son exponer los resultados de la utilizacion de la incision de cervicotomia lateral como via de abordaje selectiva a un lobulo tiroideo para la realizacion de hemitiroidectomias. Metodos Durante 2 anos seleccionamos de forma prospectiva 66 pacientes con lesiones unilobares tiroideas para la realizacion de hemitiroidectomia a traves de una via de acceso lateral. Se descarto la patologia contralateral, mediante ecografia, asi como la malignidad por la PAAF. La incision se practica en el hueco supraclavicular, verticalizandola por detras del borde interno del musculo esternomastoideo si sobrepasa los 4 cm. Se han determinado tiempos operatorios, y resultados cosmeticos segun una encuesta de grado de satisfaccion. Resultados Entre las 66 intervenciones por esta via, la edad media fue de 45 anos (23-76); la distribucion por sexos, de 55 mujeres y 11 varones; lado: 36 derecho y 30 izquierdo; lesiones: 10 multinodulares y 56 uninodulares (tamano de los nodulos, 1,8-8 cm); funcion tiroidea: 54 normofuncionales y 12 toxicos o pretoxicos. Conclusiones La cervicotomia lateral puede constituir una alternativa a la incision de Kocher para la realizacion de hemitiroidectomias, con resultados cosmeticos satisfactorios y gestos quirurgicos similares. Su gran ventaja es la nula manipulacion del area cervical correspondiente al lobulo tiroideo sano y la ausencia de colgajos.