José Antonio Pereira

Effectiveness of using blended learning strategies for teaching and learning human anatomy

Objectives  This study aimed to implement innovative teaching methods − blended learning strategies − that include the use of new information technologies in the teaching of human anatomy and to analyse both the impact of these strategies on academic performance, and the degree of user satisfaction.

Elevada incidencia de hernia incisional tras reseccion abierta y laparoscopica por cancer colorrectal

OBJECTIVES To determine the incidence of incisional hernia in patients subjected to colorectal cancer surgery. To analyse the individual risk factors and to determine which patients would benefit more from the use of prophylactic measures. PATIENTS AND METHODS A retrospective study was performed on the demographic and surgical data, as well as the complications, risk factors and outcomes of all patients subjected to colorectal cancer surgery in the period between January 2006 and September 2008. The diagnosis of incisional hernia was made by means of physical examination or by a review of the follow up CT scan. RESULTS A total of 338 patients were reviewed (249 laparotomy and 89 laparoscopy). After a median follow-up of 19.7 months, 87 patients (25.7%) were diagnosed with incisional hernia by a physical examination. The CT scan enabled 48 hernias (14.2%) not detected clinically. The incisional hernia rate was 39.9% (135 patients). There were no significant differences between patients subjected to laparotomy (40.9%) or laparoscopy (37.1%). The incisional hernia rate in overweight patients (BMI ≥ 25 Kg/m(2)), was 51.3% compared to 31.1% in patients with normal weight (P=.02). Post-surgical complications (P=.007), surgical wound infections (P=.04), and further surgery during the post-operative period (P<.0001), was also associated with a higher incidence of incisional hernia. CONCLUSION The prevalence of incisional hernia after colorectal cancer resection is higher than expected (39,9%). Patients with a BMI greater than 25 kg/m(2), and those who require further surgery are candidates to receive a prophylactic mesh.

Prophylactic synthetic mesh can be safely used to close emergency laparotomies, even in peritonitis

BACKGROUND This study was conducted to determine the efficacy and safety of the use of a partially absorbable large pore synthetic prophylactic mesh in emergent midline laparotomies for the prevention of evisceration and incisional hernia. METHODS Retrospective analysis of all patients who underwent an emergency midline laparotomy between January of 2009 and July of 2010 was performed. Patients with complicated ventral hernia repair, postoperative death, and lack of follow-up were excluded. RESULTS A total of 266 patients were included. Laparotomies were closed with a running suture of slow-reabsorbable material in 190 patients (Group S), and 50 patients within this group (26.3%) received additional retention sutures. In 76 patients (Group M), an additional partially absorbable lightweight mesh was placed in the Supra-aponeurotic space. Both groups presented similar complication rates (71.1% Group S vs 80.3% Group M, P = .97). There were no differences regarding surgical-site infection rates (17.9% Group S vs 26.3% Group M; P = .13) or postoperative mortality (13.7% Group S vs 18.3% Group M; P = .346). A total of 150 patients completed the follow-up (99 Group S; 51 Group M) at a mean time of 16.7 months. During follow-up, 36 cases of incisional hernia (24%) were diagnosed: 33 (33%) in Group S, whereas there were only three cases (5.9%) in Group M (P = .0001). Mesh removal for chronic infection was not required in any case. CONCLUSION The use of a partially absorbable, lightweight large pore prophylactic mesh in the closure of emergency midline laparotomies is feasible for the prevention of incisional hernia without adding a substantial rate of morbidity to the procedure, even if high contamination or infections are present.

Tissue Plasminogen Activator in Murine Exocrine Pancreas Cancer : Selective Expression in Ductal Tumors and Contribution to Cancer Progression

Tissue plasminogen activator (tPA) is absent from normal human pancreas and is expressed in 95% of human pancreatic adenocarcinomas. We have analyzed the expression of components of the tPA system in murine pancreatic tumors and the role of tPA in neoplastic progression. Transgenic mice expressing T antigen and c-myc under the control of the elastase promoter (Ela1-TAg and Ela1-myc, respectively) were used. tPA was undetectable in normal pancreas, acinar dysplasia, ductal complexes, and in all acinar tumors. By contrast, it was consistently detected in Ela1-myc tumors showing ductal differentiation. Crossing transgenic Ela1-myc with tPA-/- mice had no effect on the proportion of ductal tumors, indicating that tPA is not involved in the acinar-to-ductal transition. Ela1-myc:tPA-/- mice showed an increased survival in comparison to control mice. All ductal tumors, and none of the acinar tumors, overexpressed the tPA receptor annexin A2, suggesting its participation in the effects mediated by tPA. Our findings indicate that murine and human pancreatic ductal tumors share molecular alterations in the tPA system that may play a role in tumor progression.

Bone mineral density in menopausal women with primary hyperparathyroidism before and after parathyroidectomy.

The relationship between osteoporosis and primary hyperparathyroidism (pHPT) has not been definitely established because both diseases occur predominantly in postmenopausal women, and because PTH has a paradoxical effect on bone. We have investigated the prevalence of reduced bone mineral density (BMD) in women with pHPT, its relationship with metabolic parameters, and its course after parathyroidectomy. A prospective observational study was carried out on perimenopausal and postmenopausal women consecutively diagnosed and operated on for pHPT. Demographic data were recorded, as well as, PTH, Ca, calciuria/24h, P, vitamin D, adenoma weight. The BMD was measured at three sites: femoral neck (FN), proximal femur (PF), and lumbar spine (LS). Fifty-two patients were included with a mean age of 61 ± 12 years. The prevalence of reduced BMD (≤ 1SD, T-score) was 80%–100% depending on site. Parathyroid hormone was higher in patients with osteoporosis (319 ± 181 pg/ml) than in those with osteopenia (230 ± 83 pg/ml) or normal BMD (148 ± 81 pg/ml; p < 0,04). Twenty-eight patients were investigated 1 year after parathyroidectomy. The BMD improved significantly at all sites, particularly in patients with osteoporosis. Age correlated inversely with BMD increases at the femoral sites (r= –0,47; p = 0,02) but not at the LS. 25-OHD3 plasma levels correlated inversely with BMD increases at PF (r= –0,76; p < 0,0001). In pHPT, there is a high prevalence of BMD abnormalities. No metabolic variables had a definite influence on BMD values but a tendency was observed for lower BMD in severe pHPT. One year after parathyroidectomy, there were significant BMD increases that were more marked at femoral sites, in younger patients, in patients with preoperative osteoporosis, and in those with lower plasma levels of 25-OHD3.

Rapid increase in plasma levels of atrial natriuretic peptide after common bile duct ligation in the rabbit.

Previous studies have shown that common bile duct ligation in the rabbit is followed by a reduction of the extracellular water compartment. To further elucidate the mechanisms leading to volume depletion in this model, water and sodium balances and changes in plasma concentrations of atrial natriuretic peptide (ANP), vasopressin (ADH), plasma renin activity (PRA) and aldosterone (Ald) were investigated during the first 4 days after common bile duct ligation (group OJ,) or sham operation (group SO). Water and chow intakes were lower in group OJ (148 +/- 30 versus 226 +/- 40 mL/4 days; p = 0.004 and 12 +/- 9 versus 171 +/- 40 g/4 days; p = 0.0001). There were no differences in urine output. Sodium urinary losses were marginally higher in group OJ (12.4 +/- 7 versus 6.7 +/- 5 mEq/4 days; p = 0.06). Water balance was lower in group OJ (-50 +/- 56 versus 101 +/- 71 mL/4 days; p = 0.0001). At 24 hours, plasma ANP (41 +/- 7 versus 10.7 +/- 1 fmol/mL, p = 0.0001), ADH (21.8 +/- 7 versus 12.3 +/- 6 pg/mL, p = 0.008) and Ald (14.5 +/- 5 versus 3.7 +/- 3 ng/dL, p = 0.001) were higher in group OJ. These alterations persisted 72 hours after bile duct ligation, when a concomitant increase in PRA (10.7 +/- 5 versus 3 +/- 1.6 ng/dL, p = 0.006) was also observed. A group of pair-fed pair-watered sham-operated controls (group SO2, n = 13) showed a metabolic profile similar to group OJ but a low ANP concentration. Multiple venous sampling in five rabbits 24 hours after bile duct ligation showed the highest plasma levels of ANP in the aorta and infrarenal vena cava. These results suggest that common bile duct ligation in the rabbit is followed by marked hypodipsia and hypophagia, possibly mediated by ANP, leading to isotonic volume depletion and secondary activation of the water and sodium retaining hormones.

PREBIOUS trial: A multicenter randomized controlled trial of PREventive midline laparotomy closure with a BIOabsorbable mesh for the prevention of incisional hernia: Rationale and design

BACKGROUND Development of an incisional hernia is one of the most frequent complications of midline laparotomies requiring reoperation. This paper presents the rationale, design, and study protocol for a randomized controlled trial, the aim of which is to evaluate the efficacy and safety of prophylactically placing a bioabsorbable synthetic mesh for reinforcement of a midline fascial closure. METHODS The PREBIOUS trial (PREventive midline laparotomy closure with a BIOabsorbable mesh) is a multicenter randomized controlled trial in which adult patients undergoing elective or urgent open abdominal operations through a midline laparotomy incision are assigned to one of two groups based on the laparotomy closure procedure: an intervention group in which a continuous polydioxanone (PDS) suture is reinforced with a commercially available GORE® BIO-A® Tissue Reinforcement prosthesis (W.L. Gore & Associates, Flagstaff, AZ, USA), or a control group with continuous PDS suture only. Both groups are followed over 6 months. OUTCOMES The primary outcome is the appearance of incisional hernias assessed by physical examination at clinical visits and radiologically (CT scan) performed at the end of follow-up. Secondary outcomes are the rate of complications, mainly infection, hematoma, burst abdomen, pain, and reoperation. The PREBIOUS trial has the potential to demonstrate that suture plus prosthetic mesh insertion for routine midline laparotomy closure is effective in preventing incisional hernias after open abdominal surgery, to avoid the effects on those affected, such as poor cosmesis, social embarrassment, or impaired quality of life, and to save costs potentially associated with incisional hernia surgical repair.

Adenomas paratiroideos de localización intratiroidea: derechos y bajos

INTRODUCTION Intrathyroidal parathyroid adenomas (IPA) are a not an uncommon cause of persistent hyperparathyroidism. There is no consensus on their prevalence, embryological origin and position within the thyroid. PATIENTS AND METHOD Retrospective review of prospectively recorded surgical protocols of patients having had parathyroidectomy for primary (n = 437) or secondary (n = 137) hyperparathyroidism by the same surgeon. Cases with IPA were identified and the following data were recorded: age, most probable embryological origin, position within the thyroid (side and height), results of imaging techniques and surgical implications. RESULTS Seventeen IPA were detected in 16 patients (6M, 10F, prevalence 3.2%); 9 belonged to IIIP and 8 to IVP. Three lower IPA were supernumerary glands. Eight IPA were included within the right lower thyroid lobe. Twelve IPA (70.6%), were found during the initial parathyroidectomy: 3 were enucleated and 9 were treated with a partial thyroidectomy or hemithyroidectomy. Of the 3 enucleations, 2 had a local benign recurrence due to an incomplete capsule resection. No patients treated with thyroidectomy had a recurrence. The remaining 5 IPA, found in 4 patients, were not identified initially and caused persistence of the disease leading to 5 reinterventions. CONCLUSIONS IPA are present in 3% of patients submitted to parathyroidectomy. They predominate in the right thyroid lobe and can be IIIP, IVP and supernumerary. They often cause persistence. Thyroid resection affords the best results since complete enucleation can be difficult and leaving behind a fragment of the IPA results in local recurrence.

Hiperparatiroidismos debidos a glándulas paratiroides de localización torácica

Resumen Introduccion El objetivo de este estudio es el de revisar nuestra experiencia en el manejo de los hiperparatiroidismos (HPT) debidos a glandulas paratiroides de localizacion toracica. Pacientes y metodo Se han revisado retrospectivamente las historias clinicas y los protocolos operatorios de los pacientes con HPT primario (HPT1) o secundario (HPT2) que precisaron un abordaje toracico para la exeresis de una glandula paratiroides patologica. Se recogieron las variables demograficas, la realizacion o no de una paratiroidectomia previa, el resultado de las tecnicas de imagen, la situacion de la glandula, el abordaje realizado, el numero de glandulas identificadas y las complicaciones postoperatorias. Resultados Se han identificado 7 casos de glandula paratiroides toracica que representan un 3% de las 239 paratiroidectomias (190 por HPT1 y 49 por HPT2) realizadas por nuestro grupo; cinco eran varones y 2 mujeres, con edades comprendidas entre 36 y 67 anos. Cuatro pacientes presentaban HPT1 y 3, HPT2. En 6 pacientes con identificacion paratiroidea completa, la paratiroides toracica fue supernumeraria. Todos los casos fueron intervenidos con dos tecnicas de imagen (TC y Tc-mibi/SPECT) positivas. Se realizaron tres esternotomias medias totales, una esternotomia parcial, dos mediastinotomias anteriores izquierdas y una toracotomia izquierda. Las glandulas patologicas se localizaron en el mediastino anterior (5), sobre el borde izquierdo del cayado aortico (1) y en la ventana aortopulmonar (1). Conclusiones El hiperparatiroidismo por glandula patologica toracica es debido a una glandula supernumeraria, se diagnostica a menudo antes de la primera intervencion, es mas frecuente en el mediastino anterior y puede tratarse de forma selectiva obviando el acceso transesternal.

Tratamiento quirúrgico del hiperparatiroidismo secundario recidivado

Resumen Introduccion El hiperparatiroidismo secundario (HPTS) renal afecta aproximadamente al 100% de los pacientes en programa de hemodialisis periodica. Entre un 5 y un 10% de estos pacientes requerira una intervencion quirurgica para el control de la enfermedad. A pesar de una tecnica quirurgica meticulosa, la tasa de persistencia/recidiva postoperatoria del HPTS se situa entre el 2 y el 12%. Pacientes y metodo Se han revisado las reintervenciones de 7 enfermos por recidiva o persistencia de HPTS en una serie global de 56 pacientes, 3 de los cuales fueron remitidos por recidiva desde otros centros. La tecnica quirurgica que se realizo inicialmente fue la paratiroidectomia subtotal en 51 casos y la paratiroidectomia total con autoinjerto en 5 pacientes. Resultados Siete pacientes fueron reintervenidos por recidiva del HPTS, 1 de ellos en 2 ocasiones (8 reintervenciones/56 pacientes). En la primera intervencion quirurgica, en 2 pacientes se habia realizado la reseccion de solo 3 glandulas paratiroides (GPT) y la recidiva era secundaria a la presencia de una cuarta glandula GPT. En 4 pacientes se habia realizado previamente una paratiroidectomia subtotal; la recidiva de 1 de ellos se debio a la hiperplasia del remanente paratiroideo y en los otros 3 pacientes se evidencio, como causa de la recidiva, la presencia de una quinta GPT. En 1 paciente en el que se realizo una paratiroidectomia total con autoinjerto braquial la recidiva fue debida a una paratiromatosis cervical. En todos los pacientes que presentaron recidiva, la gammagrafia preoperatoria fue positiva y las pruebas radiologicas fueron de gran valor para la localizacion anatomica de la lesion y para la planificacion del abordaje quirurgico.