[Surgical treatment of tracheal stenosis. A 11-year report in a pediatric hospital]. / Tratamiento quirúrgico de la estenosis traqueal. Reporte de 11 años en un hospital pediátrico.

OBJECTIVES: To report our experience in the surgical treatment of patients having acquired and congenital tracheal stenosis. MATERIAL AND METHODS: Fifty eight patients with tracheal stenosis were surgically treated between July 2005 and May 2016, 29 were females and 29 were males. Thirty patients had acquired stenosis and 28 had congenital stenosis. RESULTS: Five to 12 rings were resected (median 5) in 26 patients, in 2 cartilage was grafted in the anterior wall, in another carinostomy was performed, and in the remaining, the trachea was replaced using an aortic cryopreserved graft. In those with congenital stenosis, 14 patients underwent slide technique; in eleven, 3 to 6 rings were resected (median 5); in 3 a patch was grafted in the anterior tracheal wall. Seven patients died: 2 with acquired stenosis and 5 with congenital stenosis. Global survival was 88% (28 of 30 patients with acquired stenosis and 23 of 28 with congenital). From 28 living patients operated on due to acquired stenosis, 26 are asymptomatic, one presents graft stenosis, and one has a stoma in the aortic graft. From 23 living patients operated on due to congenital stenosis, 20 remain asymptomatic and 3 have tracheal stents placed on. CONCLUSIONS: Surgical treatment of acquired stenosis is easier and presents less severe complications. Congenital stenosis often requires more than one procedure to control the disease, and presents a higher mortality rate.

OBJETIVOS: Describir nuestra experiencia en el tratamiento quirúrgico de pacientes con estenosis traqueal adquirida y congénita. MATERIAL Y METODOS: Cincuenta y ocho pacientes con estenosis de tráquea fueron intervenidos quirúrgicamente entre julio de 2005 y mayo de 2016, 29 eran de sexo femenino y 29 de sexo masculino. Treinta pacientes tenían una estenosis de origen adquirido y 28 de origen congénito. RESULTADOS: Fueron resecados entre 5 y 12 anillos (mediana 5) en 26 pacientes con estenosis adquirida, en 2 se efectuó injerto de cartílago en cara anterior, en 1 carinostomía, y en el restante (a este paciente se le había realizado previamente una resección laringotraqueal) se efectuó un reemplazo traqueal con aorta criopreservada. De los veintiocho pacientes con estenosis congénita, en 14 se empleó la técnica de deslizamiento, en 11 se resecaron entre 3 y 6 anillos (mediana 5), y en 3 se colocó un injerto en cara anterior de la tráquea. Fallecieron 7 pacientes: 2 con estenosis adquirida y 5 con estenosis congénita. La supervivencia global fue del 88% (28 de 30 pacientes con estenosis adquirida y 23 de 28 con congénita). De los 28 pacientes vivos operados por estenosis adquirida, 26 se encuentran asintomáticos, uno presenta estenosis del injerto y otro tiene un estoma en el injerto de aorta. De los 23 pacientes vivos operados por estenosis congénita, 20 se encuentran asintomáticos y 3 tienen endoprótesis colocadas. CONCLUSIONES: En nuestra experiencia, la resolución quirúrgica de la estenosis traqueal adquirida resultó más sencilla y presentó menos complicaciones. Los pacientes con estenosis traqueal congénita necesitaron generalmente más de un procedimiento para el control de su sintomatología, y presentaron mayor mortalidad.

[Myofibroblastic tumor of the lung: clinical features and results in 9 children]. / Tumor miofibroblástico de pulmón: aspectos clínicos y resultados en 9 niños.

INTRODUCTION: Primary lung tumors in children are rare, being the myofibroblastic lung tumor (MLT) reported as the most common. Nevertheless the literature about it is scarce, and mostly consistent of case reports. The aim of this article is to describe the results obtained in a group of patients with this tumor treated in a tertiary pediatric hospital. METHODS: A single institution retrospective chart review was performed with institutional review board approval. All patients treated between 1990 and 2010 with diagnosis of MLT were included. Age, symptoms at presentation, surgical procedures, complications, histopathology and follow-up were reviewed. RESULTS: 9 patients were identified. The commonest symptoms at presentation were fever and cough (n=6), and seizures (n=2). Surgical treatment consisted in complete resection in 8 patients and partial resection in 1. To achieve this 3 patients underwent pneumonectomy and 6 lobectomy. Two of the patients with pneumonectomy required also a partial resection of the right atrium and both had cerebral lesions. The mean follow-up was 2.8 years (r:0.16-12) and all the patients that remained in follow-up (66%) are alive at the moment. DISCUSSION: Complete surgical resection in MLT is possible, however, to achieve this complex procedures and a multidisciplinary approach might be needed. Although the potential of distant metastasis is not clearly reported, we think that it is a topic that must be carefully revised.

Gastroschisis: deferred closure with releasing incisions. A case report. / Gastrosquisis: cierre diferido con incisiones de descarga. Reporte de caso.

Primary defect closure is the surgical treatment of choice in gastroschisis. When this is not feasible, a silo is required to progressively reduce the organs and perform a deferred closure of the wall. We present the case of a newborn with gastroschisis that required the use of a silo. Once the silo had been created, the distance between borders did not allow the defect to be closed, so decision was made to conduct releasing aponeurotic incisions for mobilization purposes.Progression was uneventful, and enteral nutrition was initiated at 24 days of life. Total enteral total nutrition was achieved at 40 days of life. He received parenteral nutrition for 36 days. He was discharged at 59 days of life. Abdominal wall treatment through releasing incisions allows prostheses to be avoided and represents an alternative for these patients.

El tratamiento quirúrgico de referencia en la gastrosquisis es el cierre primario del defecto. En los casos en que esto no es posible es necesario confeccionar un silo para reducir progresivamente las vísceras y realizar así el cierre diferido de la pared. Presentamos el caso de un recién nacido con gastrosquisis, que luego de confeccionar un silo, la distancia entre los bordes no permitía cerrar el defecto, por lo que se decidió realizar incisiones de descargas aponeuróticas para movilizar los mismos. El paciente evolucionó sin complicaciones, iniciando alimentación enteral a los 24 días de vida, alcanzando el aporte enteral total a los 40 días de vida. Recibió nutrición parenteral durante 36 días. Fue dado de alta a los 59 días. El tratamiento de la pared abdominal mediante incisiones de descarga permite evitar el uso de prótesis y agrega otra alternativa para el tratamiento de estos pacientes.

[Analysis of clinical-surgical course of neonates with long-gap esophageal atresia during their spontaneous growth]. / Análisis de la evolución clinico-quirúrgica de neonatos con atresia de esófago con cabos distantes (Long Gap) durante el crecimiento espontáneo de los mismos.

INTRODUCTION: Esophageal atresia (EA) is one of the most prevalent surgical conditions in the newborn. Sometimes early oesophageal anastomosis can't be done due to the esophageal gap. Long gap (LG) definition is not precise. Although consensus exist about conservation of owns esophagus is the best therapeutic option, literature is not clear about how long and under what circunstances is advisable to wait for the spontaneous esophageal pouches to growth (P. Puri approach). Furthermore at present we don't even know the real repercussion that this waiting can implicate. OBJECTIVE: The aim of the study was to evaluate the clinical and surgical outcome of newborns with EALG during their stay in a neonatal intensive care unit (NICU) at a third level children's hospital. MATERIALS AND METHODS: We retrospectively reviewed the charts of all newborn with EA admitted in the NICU from January 2002 to December 2006 in order to analyze sex, gestacional age, weight, type of EA, LG, respiratory and surgical complications, length of stay and mortality. RESULTS: During the study time period 64 newborns with EAwere admitted, 21 (33%) had EALG (our population). We underwent primary repair with esophageal anastomosis in 8 newborns at 80 +/- 40 days. All of them had gastroesophageal reflux, 50% presented different complications such as anastomotic leak, stricture and mediastinal infections. 13 patients required an esophagostomy at a mean age of 46 +/- 34 days due to a lack of growth of esophageal's pouches and/or serious respiratory complications. There were no deaths. CONCLUSIONS: There were high percentages of esophagostomized patients. The result of waiting for the primary repair was a high number of children with chronic lung disease and a high rate of serious complications. Esophageal anastomosis were accompanied by long hospital stays and no clear benefits. The early application of dynamic esophageal lengthening should be explored as an alternative strategy for newborns with EALG.

Comparación de vía mediastinal posterior versus vía retroesternal para el reemplazo de esófago con ascenso gástrico parcial. Motivo de un cambio de estrategia / Comparison of posterior mediastinal versus retrosternal route for esophageal replacement with partial gastric pull-up. Rationale for a change in strategy

Introducción: existen dos rutas para realizar el reemplazo de esófago (RE), la retroesternal (RRE) y la mediastinal posterior (RMP). El objetivo del estudio es comparar los pacientes que recibieron un ascenso gástrico parcial empleando estas dos rutas. Material y métodos: Se revisaron las historias clínicas de 51 pacientes con ascenso gástrico parcial, en 27 años en el Hospital Garrahan. Se utilizó la vía RRE en 25 casos y la RMP en 26. Fueron comparados los datos epidemiológicos de los grupos y las variables para valorar la dificultad del acto quirúrgico, evolución inmediata y alejada. El estudio es comparativo, retro-prospectivo y longitudinal. Resultados: las características generales de los pacientes fueron similares. Los que recibieron el ascenso gástrico por vía RMP presentaron una menor incidencia de dehiscencia (p=0,017), de enfermedad por reflujo gastroesofágico (ERGE) (p=0,001) y de dumping (p=0,0001). No hubo diferencias estadísticamente significativas entre los dos grupos al comparar la duración del procedimiento, días de internación total y en Unidad de Cuidados Intensivos (UCI), días de permanencia en asistencia respiratoria mecánica (ARM), inicio de alimentación oral y estenosis de la anastomosis. Se observó una tendencia clínicamente relevante, que no alcanzó significancia estadística en las complicaciones intraquirúrgicas y número de dilataciones postoperatorias. No hubo necrosis del ascenso. Fallecieron 2 pacientes. Conclusiones: considerando la menor incidencia de dehiscencia, ERGE y dumping reemplazados por RMP, elegimos a ésta como nuestra primera opción para el reemplazo esofágico en la infancia (AU)

Introduction: The two routes for esophageal replacement (ER) are retrosternal (RRE) and posterior mediastinal (PMR). The aim of the study was to compare patients who received a partial gastric pull-up using either of these two routes. Material and methods: The clinical records of 51 patients who underwent partial gastric pull-up over 27 years at the Garrahan Hospital were reviewed. The RRE route was used in 25 and the RMP in 26 cases. The epidemiological data of the groups and the variables to evaluate the complexity of the surgical procedure, and shortand long-term outcome were compared. A comparative, retroprospective, and longitudinal study was conducted. Results: the general characteristics of the patients were similar. Those who underwent gastric pull-up via PMR had a lower incidence of dehiscence (p=0.017), gastroesophageal reflux disease (GERD) (p=0.001), and dumping (p=0.0001). No statistically significant differences were found between the two groups when comparing the duration of the procedure, days of total hospital and intensive care unit (ICU) stay, days on mechanical ventilation (MV), initiation of oral feeding and stenosis of the anastomosis. A clinically relevant trend, which did not reach statistical significance, was observed in intraoperative complications and number of postoperative dilatations. There was no necrosis of the pull-up. Two patients died. Conclusions: considering the lower incidence of dehiscence, GERD, and dumping associated with PMR, this was our first choice for esophageal replacement in infancy (AU)

Transforming growth factor-beta1 gene transfer ameliorates acute lung allograft rejection.

BACKGROUND: The aim of the current work was to study the feasibility of functional gene transfer using the gene encoding for transforming growth factor-beta1, a known immunosuppressive cytokine, on rat lung allograft function in the setting of acute rejection. METHODS: The rat left lung transplant technique was used in all experiments, with Brown Norway donor rats and Fischer recipient rats. After harvest, left lungs were transfected ex vivo with either sense or antisense transforming growth factor-beta1 constructs complexed to cationic lipids, then implanted into recipients. On postoperative days 2, 5, and 7, animals were put to death, arterial oxygenation measured, and acute rejection graded histologically. RESULTS: On postoperative day 2, there were no differences in acute rejection or lung function between animals treated with transforming growth factor-beta1 and control animals. On postoperative day 5, oxygenation was significantly improved in grafts transfected with the transforming growth factor-beta1 sense construct compared with antisense controls (arterial oxygen tension = 411 +/- 198 vs 103 +/- 85 mm Hg, respectively; P =.002). Acute rejection scores from lung allografts were also significantly improved, corresponding to decreases in both vascular and airway rejection (vascular rejection scores: 2.0 +/- 0. 5 vs 2.8 +/- 0.6; P =.04; airway rejection scores: 1.3 +/- 0.7 vs 2. 3 +/- 0.8, respectively; P =.02). The amelioration of acute rejection was temporary and decreased by postoperative day 7. CONCLUSIONS: The feasibility of using gene transfer techniques to introduce novel functional genes in the setting of lung transplantation is demonstrated. In this model of rat lung allograft rejection, gene transfer of transforming growth factor-beta1 resulted in temporary but significant improvements in lung allograft function and acute rejection pathology.

Liposome-mediated gene transfer in rat lung transplantation: A comparison between the in vivo and ex vivo approaches.

OBJECTIVE: We compared the efficacy of in vivo and ex vivo liposome transfection in rat lung transplantation. METHODS: (1) Chloramphenicol acetyltransferase group: Fischer rats underwent isogeneic transplantation (n = 4 per group). Recipients were put to death on postoperative day 2 for chloramphenicol acetyltransferase activity. Ex vivo setting: Grafts received cDNA complexed or not with liposomes and were transplanted after 1.5 or 10 hours at 10 degreesC. In vivo setting: Donors were intravenously injected with cDNA complexed or not with liposomes. Lungs were harvested after 1.5 or 10 hours, preserved at 10 degreesC, and transplanted. (2) Transforming growth factor-beta1 group: Brown-Norway rats served as donors and Fischer rats as recipients. All grafts were preserved for 3 hours at 10 degreesC. On postoperative day 5, arterial oxygenation and histologic rejection scores were assessed. Ex vivo setting: Grafts received transforming growth factor-beta1 sense (n = 8) or antisense (n = 7) complexed with liposomes or cDNA alone (n = 5). In vivo setting: Donors were intravenously injected with liposome:transforming growth factor-beta1 sense cDNA (n = 7). Exposure time was 3 hours. RESULTS: (1) Chloramphenicol acetyltransferase-transfection was superior in the ex vivo group but was not statistically different for longer exposure times. (2) Transforming growth factor-beta1-arterial oxygenation was superior in the ex vivo liposome:sense group. cDNA alone was inefficient. Rejection scores were not statistically different between ex vivo and in vivo liposome:sense groups but were better when the ex vivo liposome:sense group was compared with the cDNA alone or the antisense groups. CONCLUSIONS: (1) With current liposome technology, the ex vivo route is superior to the in vivo approach; (2) cDNA alone does not provide transgene expression at levels to produce a functional effect.

Bounds on transverse momentum dependent distribution and fragmentation functions

We give bounds on the distribution and fragmentation functions that appear at leading order in deep inelastic one-particle inclusive leptoproduction or in Drell-Yan processes. These bounds simply follow from positivity of the defining matrix elements and are an important guidance in estimating the magnitude of the azimuthal and spin asymmetries in these processes.

Exhaled nitric oxide correlates with experimental lung transplant rejection.

BACKGROUND: Increased nitric oxide production accompanies acute lung allograft rejection. Transforming growth factor-beta1 is an immunosuppressive cytokine capable of ameliorating acute rejection. The purpose of this study was to determine whether exhaled nitric oxide (eNO) concentrations correlated with the degree of acute rejection. METHODS: A model of acute lung transplant rejection in the rat was developed, and concentrations of eNO were measured at the time of animal sacrifice. In group 1 (partial immunosuppression), donor lungs were pretreated with transforming growth factor-beta1 before implantation. In group 2 (fulminant acute rejection), no immunosuppression was used. In group 3 (full immunosuppression), recipients received cyclosporine. Group 4 were normal rats. RESULTS: When measured from both lungs, eNO concentrations were 4.97+/-0.68 versus 6.73+/-2.90 ppb for groups 1 and 2, respectively (p = 0.58). When measured selectively from transplanted left lungs, eNO concentrations were 8.61+/-0.97 versus 42.14+/-7.27 ppb, respectively (p<0.001). In groups 3 and 4, eNO concentrations were 1.02+/-0.21 and 1.51+/-0.74 ppb, respectively. CONCLUSIONS: Exhaled nitric oxide is elevated in fulminant acute rejection, is reduced after partial immunosuppression using transforming growth factor-beta1 gene therapy, and is in the normal range in cyclosporine-treated animals. The measurement of eNO correlates with the degree of acute lung allograft rejection and may serve as a noninvasive measure of acute lung transplant rejection in the clinical setting.

Isolated lung liposome-mediated gene transfer produces organ-specific transgenic expression.

BACKGROUND: Gene therapy is a promising strategy for the treatment of inoperable pulmonary tumors and rejection after lung transplantation. However, unlike ex vivo administration, intravenous in vivo transfection lacks organ specificity and has a limited duration of expression. The objectives of this study were to limit transfection to a single lung and to increase the duration of gene expression in vivo. METHODS: Sixteen male Fisher rats were anesthetized and divided into two groups. Animals in group I (n = 7) received an intrajugular administration of 1,320 microg of chloramphenicol acetyl transferase (CAT) complementary DNA complexed with cationic liposomes. Animals in group II (n = 9) received 660 microg of CAT complementary DNA complexed with cationic liposomes into the pulmonary artery of an isolated left lung over 10 minutes. After 40 minutes of incubation, the lung was flushed with 10 mL of normal saline solution, and the perfusate was suctioned through a left pulmonary venotomy. The circulation to the left lung was then restored. After 48 hours, the animals were divided into subgroups (a and b) and CAT activity was assessed in the lungs, hearts, livers, and kidneys of groups Ia (n = 3) and IIa (n = 5). After 21 days, CAT activity was assessed in the left lungs of groups Ib (n = 4) and IIb (n = 4). RESULTS: After 48 hours, animals that had received intravenous administration of CAT cDNA showed strong expression in the lungs and hearts and negligible expression in the livers and kidneys. In contrast, animals in group IIa, which had received isolated left lung perfusion of CAT cDNA showed expression only in the left lung. After 21 days, the left lungs of animals in group Ib, which had received intravenous administration of CAT complementary DNA, showed no CAT expression, but the left lungs of animals in group IIb, which had received isolated left lung perfusion of CAT complementary DNA, exhibited strong CAT expression. CONCLUSIONS: Compared with intravenous administration, isolated lung liposome-mediated gene transfer provides prolonged organ-specific gene expression. This provides a useful model to study the effects of gene therapy on pulmonary tumors, which may have further application when gene therapy is used in clinical practice.

Pre-arrest heparinization and ventilation during warm ischemia preserves lung function in non-heart-beating donors.

BACKGROUND/PURPOSE: To solve the problem of donor scarcity, many attempts have been made including improved community education, relaxed organ acceptance criteria, increased reliance on single lung transplantation, and the use of partial organ donation. Unfortunately, these efforts have produced only modest increases in lung allograft availability; therefore, the so-called non-heart-beating organ donation must be considered. The aim of this study is to assess the viability of the non-heart-beating donor (NHBD) lung transplant rat model and determine the best strategy to manage the donor before and after cardiac arrest. METHODS: Fifty-five inbred Fischer rats were used as donors and recipients in an isogenic model of left lung transplantation. The rats were divided into 6 groups (n = 5): group I, normal controls without transplant; group II, heart-beating donor controls (HBD); group III, NHBD, no heparin, no ventilation during warm ischemia; group IV, NHBD, heparin, no ventilation; group V, NHBD, no heparin, ventilation; group VI, NHBD, heparin, ventilation. All lungs were stored at 4 degrees C for 4 hours. Animals were killed 24 hours after implantation. Gas exchange, pulmonary artery pressure, compliance, chest x-ray score, and histological score were assessed. RESULTS: Heparinized and ventilated animals during warm ischemia (group VI) had similar performance than those transplanted without warm ischemia time in a scenario of heart-beating donor (group II). Groups III, IV, and V transplanted lungs showed severe damage. CONCLUSIONS: The authors conclude that the rat lung transplantation model is useful to study the phenomena that occur in a setting of transplantation using NHBD and that heparinization and ventilation before cardiac arrest is the best strategy to manage non-heart-beating donors in this model.

Apoptosis en trasplante de pulmón. Influencia del lavado y la reperfusión del órgano / Apoptosis in lung transplantation. Influence of lavage and reperfusion on the organ

Objetivo: Determinar el rol de la irrigación con soluciones de preservación, la reperfusión y el rechazo en la apoptosis pulmonar en un escenario de trasplante pulmonar. Material y método: Venticuatro cerdos Landrace con un peso de 15 a 30 kilogramos fueron usados como donantes y receptores en un modelo de trasplante pulmonar izquierdo, con 5 días de sobrevida. Las muestras se obtuvieron en la siguiente secuencia: 1A: Donante, pulmón izquierdo inmediatamente luego de la apertura del torax. 1B: donante, pulmón derecho, inmediatamente luego de la apertura del tórax. 2A: Donante pulmón izquierdo, inmediatamente luego de la irrigación del organo. 2B Donante, pulmón derecho, sin irrigar. 3A: Pulmón izquierdo implantado, 1 hora luego de reperfundido en el receptor . 3B: Pulmón derecho (nativo), 1 hora luego de reperfundido el pulmón donante en el receptor. 4A: Pulmón izquierdo, biopsia transbronquial a las 48 horas postrasplante. 4B: Pulmón derecho, biopsia transbronquial a las 48 horas postransplante. 5A: Púlmón izquierdo, 5º día postrasplante (sacrificio). Todos los pulmones fueron irrigados con solución de Euro-Collins fría (4Cº) durante la ablación. Seis receptores no recibieron inmunosupresión y otros 6 receptores recibieron 15 mg/KG/ día de ciclosporina intravenosa. Los niveles plasmáticos de ciclosporina fueron dosados en tiempo 0 al 2º y 5º día postrasplante. Cada muestra fue analizada por un observador ciego para determinar el grado de rechazo (A0 y A1 negativo. A2. A3 y A4 positivo), proliferación celular, y el índice de apaptosis en neumonocitos I y II empleando la técnica de TUNEL y Caspasa. Las pruebas de Chi cuadrado; prueba de t de student y kruskal Wallis fueron utilizadas para el análisis estadístico. Se consideró significativo un valor de p menor a 0.05. Resultados: El grado de rechazo fue negativo en todas las muestras excepto en 4A (1 animal) y 5A (5 animales sin ciclosporina y 3 animales de los que recibieron ciclosporina) (p<0.05)

Infecciones asociadas a catéteres implantables / Infections related to implantable venous devices

Durante el período comprendio entre diciembre de 1991 y noviembre de 1993 fueron analizados 216 catéteres implantados en 208 pacientes con enfermedades hemato-oncológicas. Las enfermedades de base que predominaron fueron: leucemia (114), tumores sólidos (64) y linfoma (16). El sitio más frecuente de colocación de los catéteres fue la vena más yugular externa (76 por ciento). Se registraron 13 infecciones y 21 bacteriemias asociadas a catéter. Los microorganismos más frecuentemente aislados fueron candida sp y Staphylococus coagulasa negativo. El tiempo de permanencia del catéter osciló entre 7 y 622 días con un total acumulado de 60918 días. las tasas de infección y bacteriemia asociadas a catéter fueron de 0.22 y 0.41 cada 1000 días de uso, respectivamente. El 37 por ciento de los catéteres tuvieron que ser removidos, siendo la infección la causa más frecuente. La tasa de infección de nuestros pacientes fue baja; ésto remarca que el manejo organizado y normalizado de estos catéteres redunda en una menor tasa de infección.

En un modelo ortotópico de trasplante de tráquea, la irrigación con Euro-Collins proporciona mayor sobrevida al injerto / In an orthopic model of tracheal transplant, irrigation with Euro-Collins provides better graft survival

El objetivo de este estudio es investigar la influencia de la irrigación con solución de Euro-Collins enun modelo isogénicos de trasplante ortotópico de tráquea con 24 horas de preservación sin omentopexia.Veinticuatro ratas Sprague-Dawley endocriadas,con un peso entre 300 y 340 gramos fueron utilizadas como donantes y receptores.Se analizaron 2 grupos:A tráqueas perfundidas con solución de Euro-Collins durante la ablación;y B:tráqueas ablacionadas sin irrigación con la solución preservante.Los injertos se implantaron ortotópicamente en la región cervical luego de 24 horas de preservación en heladera a 4 grados.Se evaluó la sobrevida(en días)y alteraciones macro y microscópicas del injerto.La media de sobrevida fue significativamente mayor(p =0.01)en los animales del grupo A;52+/-36 días,rango 6-90 días,comparado con los animales del grupo B:2,8+/-2,4 días,rango 1-7.Dos animales del grupo A fueron sacrificados a los 90 días,límite de sobrevida máxina establecido.Los escores del material obtenido en el momento del deceso o sacrificio fueron 1 para el equipo A y 2,3 para el grupo B,alcanzando una diferencia estadísticamente significativa(p

Comparación de distintos métodos de preservación traqueal / Comparing the different methods of tracheal preservation

El objetivo de este estudio fue comparar distintos métodos de preservación traqueal en un modelo isogénico heterotópico de implante inmediato y con 24 horas de preservación.Ochenta ratas Sprague-Dawley endocriadas,con un peso de 300-340 gramos fueron utilizadas como donantes y receptores divididas en ocho grupos:A:trasplante 24 horas,no Euro-Collins,no criopreservación,B:traplante inmediato,si Euro-Collins,no crioprservación,C:traplante 24 horas,no Euro-Collind,nocriopreservación,D:trasplante 24 horas,si Euro-Collins,no criopreservación;E:criopreservación luego de 24 horas a 4 grados C,si Euro Collins;F:crioperservación inmediata,no Euro-Collins;G criopreservación luego de 24 horas a 4 grados,si Euro-Collins;H:criopreservación inmediata,si Euro-Collins.Todos los injertos fueron implantados en epiplpón.Tres muestras para estudio microscópico fueron tomadas de cada espécimen:inmediatamente después de la ablación,inmediatamente antes del implante(al finalizar el periódo de preservación)y en el momento del sacrificio.No hubo muertes antes del tiempo establecido.Los escores de daño histológico del material obtenido en el momento del sacrificio fueron:grupo A:3,1;grupo B:1,7;Grupo C:3;grupo D:1,1;Grupo E:3,2;Grupo F:3,7;Grupo G:1,3 y Grupo H:1.Todos los injertos presentabam la luz ocupada por granulomas.La preservación de Euro Collins es superior a la preservación sin Euro Collins tanto en tráqueas criopreservadas como no criopreservadas.La criopreaservación es una estrategia válida para la obtención de injertos traqueales.Los injertos criopreservados persentan lesiones leves aunque más severas que aquellos no criopreservados.La irrigación con euto Collins permite preservar tráqueas hasta 24 horas a 4 grados C