RESUMO
BACKGROUND: Short bowel syndrome (SBS) is still a life-threatening disease in both children and adults. Although the therapeutic options are improving, challenges still remain, and to overcome these challenges is a major focus of SBS research today. In order to simulate anatomical and physiological conditions similar to those in humans for research, porcine models of SBS are often used. Various approaches for generating SBS models have been described in the literature. METHODS/RESULTS: In this work, we present a review of different types of porcine models of SBS and outline the differences between those models regarding types of animals, surgical procedures, monitoring, and methods of assessment. CONCLUSION: The aim of this study was to select the most suitable SBS model regarding the purpose of the research.
Assuntos
Modelos Animais de Doenças , Síndrome do Intestino Curto/etiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Monitorização Fisiológica , Síndrome do Intestino Curto/fisiopatologia , SuínosRESUMO
BACKGROUND: Swine and human beings have many aspects in common that make swine a well-characterized large animal model for kidney transplantation (KTx). However, pigs have some peculiar anatomical characteristics that standardized techniques must adapt to. The aim of this study was to prepare an up-to-date guideline for porcine KTx. METHODS: To achieve this goal, we performed a Medline search using the terminology 'kidney' or 'renal' and 'transplantation' and 'pig' or 'swine' or 'porcine'. We found over 1,300 published articles since 1963. Only 13 studies focused on the surgical aspect. Furthermore, we reviewed related books and articles about swine anatomical characteristics and surgery. Finally, our experimental experiences of KTx during the last few decades were added to this collection. RESULTS: Proper hosting, fasting, anesthesia, medical therapy and monitoring can prevent postoperative complications. Explantation with a Carrel patch of the aorta facilitates the implantation and prevents future stenosis. Native nephrectomy makes the follow-up of the implanted organ more precise. KTx in the infrarenal fossa via end-to-side anastomosis to the aorta and inferior vena cava followed by ureteroureterostomy are the recommended options for KTx in pigs compared to other possible methods. CONCLUSION: Pigs, with respect to their characterizations, constitute one of the best large animal models for KTx. Preoperative preparations are as important as the intra- and postoperative management. Using the most adaptable methods of surgery with respect to the specific anatomical characteristics of pigs can prevent undermining the studies and avoid preventable complications and pitfalls.
Assuntos
Transplante de Rim/métodos , Suínos/cirurgia , Animais , Modelos Animais , Nefrectomia , Assistência PerioperatóriaRESUMO
Background: Liver resection is the only curative therapeutic option for intrahepatic cholangiocarcinoma (ICC), but the approach to recurrent ICC is controversial. This study analysed the outcome of liver resection in patients with recurrent ICC. Methods: Demographic, radiological, clinical, operative, surgical pathological and follow-up data for all patients with a final surgical pathological diagnosis of ICC treated in a tertiary referral centre between 2001 and 2015 were collected retrospectively and analysed. Results: A total of 190 patients had liver resection for primary ICC. The 1-, 3- and 5-year overall survival (OS) rates were 74·8, 56·6 and 37·9 per cent respectively. Independent determinants of OS were age 65 years or above (hazard ratio (HR) 2·18, 95 per cent c.i. 1·18 to 4·0; P = 0·012), median tumour diameter 5 cm or greater (HR 2·87, 1·37 to 6·00; P = 0·005), preoperative biliary drainage (HR 2·65, 1·13 to 6·20; P = 0·025) and local R1-2 status (HR 1·90, 1·02 to 3·53; P = 0·043). Recurrence was documented in 87 patients (45·8 per cent). The mean(s.d.) survival time after recurrence was 16(17) months. Independent determinants of recurrence were median tumour diameter 5 cm or more (HR 1·71, 1·09 to 2·68; P = 0·020), high-grade (G3-4) tumour (HR 1·63, 1·04 to 2·55; P = 0·034) and local R1 status (HR 1·70, 1·09 to 2·65; P = 0·020). Repeat resection with curative intent was performed in 25 patients for recurrent ICC, achieving a mean survival of 25 (95 per cent c.i. 16 to 34) months after the diagnosis of recurrence. Patients deemed to have unresectable disease after recurrence received chemotherapy or chemoradiotherapy alone, and had significantly poorer survival. Conclusion: Patients with recurrent ICC may benefit from repeat surgical resection.
Antecedentes: La resección hepática es la única opción terapéutica curativa para el colangiocarcinoma intrahepático (intrahepatic colangiocarcinoma, iCCA), pero el enfoque terapéutico de la recidiva del iCCA es controvertido. En este estudio se analizaron los resultados de la resección hepática en pacientes con recidiva de un iCCA. Métodos: Se recopilaron de forma retrospectiva y se analizaron los datos demográficos, radiológicos, clínicos, quirúrgicos, de anatomía patológica y de seguimiento de todos los pacientes con diagnóstico anatomopatológico definitivo de iCCA en un centro de referencia terciario entre 2001 y 2015. Resultados: En total, 190 pacientes se sometieron a resección hepática por iCCA primario. La supervivencia global (overall survival, OS) a 1, 3 y 5 años fue del 75%, 57% y 38%, respectivamente. La edad de ≥ 65 años (cociente de riesgos instantáneos, hazard ratio, HR 2,2, i.c. del 95% 1,24,0, P = 0,012), la mediana del diámetro del tumor ≥ 5 cm (HR 2,9, i.c. del 95% 1,46,0, P = 0,005), el drenaje biliar preoperatorio (HR 2,6, i.c. del 95% 1,36,2, P = 0.025) y el estado local R1/2 (HR 1,9, i.c. del 95% 1,03,5, P = 0,043) fueron factores pronósticos independientes de la OS. La recidiva se documentó en 87 (45,8%) pacientes. El tiempo medio de supervivencia después de la recidiva fue de 16 ± 2 meses. Los factores pronósticos independientes de recidiva fueron la mediana del diámetro del tumor ≥ 5 cm (HR 1,7, i.c. del 95% 1,12,7, P = 0,020), el tumor de alto grado (G3G4) (HR 1,6, i.c. del 95% 1,02,5, P = 0,034) y el estado local R1 (HR 1,7, i.c. del 95% 1,12,6, P = 0,020). La resección repetida con intención curativa se realizó en 25 pacientes con iCCA recidivado, con una supervivencia media de 25 meses (i.c. del 95% 1634 meses) tras el diagnóstico de recidiva. Los pacientes que se consideraron no resecables después de la recidiva se sometieron a quimioterapia o quimiorradioterapia y presentaron una supervivencia significativamente peor. Conclusión: Los pacientes con recidiva de un iCCA pueden beneficiarse de la resección quirúrgica repetida.
Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/cirurgia , Hepatectomia , Recidiva Local de Neoplasia/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Modelos de Riscos Proporcionais , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Centros de Atenção Terciária/estatística & dados numéricos , Adulto JovemRESUMO
The organ shortage has driven many transplant centers to accept extended donor criteria and to modify graft allocation policies. This study was designed to analyze the impact of applying extended donor criteria (EDC) in orthotopic liver transplantation (OLT). Between December 2001 and December 2004, we performed 165 primary cadaveric whole OLTs. Up to three EDC, that is, ventilation >7 days; aminotransferases (ALT or AST) >3 x normal; bilirubin >3 mg/dL; anti-HBc or HBs Ag positivity; donor age >65 years; liver steatosis >40%; donor body mass index >30; cold ischemia time >14 hours; peak serum Na(+) >165 mmol/L; history of extrahepatic malignancy; or previous drug abuse were present in 55% of all grafts. Both univariate and multivariate analysis revealed that EDC status had no effect on graft or patient survival, the necessity for retransplantation, the length of intensive care/intermediate care unit stay, mechanical ventilation, complications, or posttransplant laboratory findings. Recipient age of >/=55 years was the only independent prognostic factor for survival, regardless of EDC. These findings suggested that the use of grafts from EDC donors are safe and expand the donor pool.
Assuntos
Transplante de Fígado/fisiologia , Doadores de Tecidos/provisão & distribuição , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Testes de Função Hepática , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Seleção de Pacientes , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
BACKGROUND/AIMS: Warm ischemia to liver with subsequent Kupffer cell-dependent pathology is associated with many clinical conditions. Taurine prevents Kupffer cell activation and improves graft survival after experimental cold ischemia and liver transplantation. Thus this study was designed to assess its effects after warm hepatic ischemia. METHODS: The left liver lobe of female Sprague-Dawley rats (170-210 g) underwent 60 min of warm ischemia. Animals were given either intravenous taurine or Ringer's solution 10 min prior to warm ischemia. Transaminases, histology, in vivo microscopy, intercellular adhesion molecules-1 (ICAM-1) expression, TNF-alpha and tissue hydroperoxide were compared between groups using analysis of variance (ANOVA) or ANOVA on ranks as appropriate. RESULTS: Taurine significantly decreased transaminases and improved histologic outcome. Phagocytosis of latex beads, serum TNF-alpha levels and tissue hydroperoxide concentrations were also significantly reduced. Stickers in sinusoids and post-sinusoidal venules significantly decreased. In parallel, both leukocyte infiltration and ICAM-1 expression decreased (p < 0.05), while flow velocity of red blood cells as well as sinusoidal perfusion rate were improved (p < 0.05). CONCLUSION: This study demonstrates that taurine blunts Kupffer cell-dependent hepatic pathology after warm ischemia in vivo via mechanisms including leukocyte-endothelial interaction, microcirculation disturbances and protection against lipid peroxidation.
Assuntos
Células de Kupffer/efeitos dos fármacos , Fígado/lesões , Ativação de Macrófagos/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Taurina/uso terapêutico , Animais , Comunicação Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Feminino , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/imunologia , Microcirculação/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/metabolismo , Taurina/farmacologia , Fator de Necrose Tumoral alfa/sangueRESUMO
BACKGROUND: Routine use of intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC) is a matter of debate. METHODS: Data from 2,130 consecutive LCs and patients' follow-up during 9 years were collected and analyzed. During the first 4 years of the study, 800 patients underwent LC, and IOC was performed selectively (SIOC). Thereafter, 1,330 patients underwent LC, and IOC was routinely attempted (RIOC) for all. RESULTS: In the IOC group, 159 patients met the criteria for SIOC, which was completed successfully in 141 cases (success rate, 88.6%). Bile duct calculi were found in nine patients. All other patients with no criteria or failed SIOC were followed, and in nine patients retained stones were documented. Thus, the incidence of ductal stones was 1.1% and sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) for the detection of ductal stones were 50, 100, 98.6, and 100%, respectively. In the RIOC group, IOC was routinely attempted in 1,330 patients and was successful in 1,133 (success rate, 90.9%; p = 0.015). Bile duct stones were detected in 37 patients (including 14 asymptomatic stones). In two cases, IOC failed to reveal ductal stones (false negative). There was no false-positive IOC. Therefore, with RIOC policy, the incidence of ductal stones, sensitivity, specificity, NPV, and PPV were 3.3, 97.4, 100, 99.8, and 100%, respectively (significantly higher for success rate, incidence, sensitivity, and NPV; p < 0.05). Abnormal IOC findings were also significantly higher in the RIOC group. Common bile duct injury occurred only in the SIOC group [two cases of all 2,130 LCs (0.09%)]. CONCLUSION: RIOC during LC is a safe, accurate, quick, and cost-effective method for the detection of bile duct anatomy and stones. A highly disciplined performance of RIOC can minimize potentially debilitating and hazardous complications of bile duct injury.
Assuntos
Colangiografia , Colecistectomia Laparoscópica , Cuidados Intraoperatórios , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Ducto Colédoco/lesões , Feminino , Seguimentos , Cálculos Biliares/diagnóstico por imagem , Humanos , Complicações Intraoperatórias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Ferimentos e Lesões/prevenção & controleRESUMO
BACKGROUND: With the increasing use of the surgical robotic system in the clinical arena, appropriate training programs and assessment systems need to be established for mastery of this new technology. The authors aimed to design and evaluate a clinic-like training program for the clinical introduction of the da Vinci robotic system in visceral and vascular surgery. METHODS: Four trainees with different surgical levels of experience participated in this study using the da Vinci telemanipulator. Each participant started with an initial evaluation stage composed of standardized visceral and vascular operations (cholecystectomy, gastrotomy, anastomosis of the small intestine, and anastomosis of the aorta) in a porcine model. Then the participants went on to the training stage with the rat model, performing standardized visceral and vascular operations (gastrotomy, anastomosis of the large and small intestines, and anastomosis of the aorta) four times in four rats. The final evaluation stage was again identical to the initial stage. The operative times, the number of complications, and the performance quality of the participants were compared between the two evaluation stages to assess the impact of the training stage on the results. RESULTS: The operative times in the final evaluation stage were considerably shorter than in the initial evaluation stage and, except for cholecystectomies, all the differences reached statistical significance. Also, significantly fewer complications and improved quality for each operation in the final evaluation stage were documented, as compared with their counterparts in the initial evaluation stage. These improvements were recorded at each level of experience. CONCLUSIONS: The presented experimental small and large animal model is a standardized and reproducible training method for robotic surgery that allows evaluation of the surgical performance while shortening and optimizing the learning-curve.
Assuntos
Educação Médica , Robótica/educação , Procedimentos Cirúrgicos Operatórios/métodos , Materiais de Ensino , Procedimentos Cirúrgicos Vasculares/métodos , Vísceras/cirurgia , Animais , Competência Clínica , Educação Médica Continuada , Avaliação Educacional/métodos , Humanos , Internato e Residência , Aprendizagem , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Suínos , Fatores de Tempo , Procedimentos Cirúrgicos Vasculares/efeitos adversosRESUMO
BACKGROUND: Organ function after liver transplantation is determined by ischemia-reperfusion injury. Destruction of Kupffer cells with gadolinium chloride (GdCl3) has been shown to have a possible preventive effect on the extent of this injury, which can be extrapolated by analyzing the distribution of hepatic microperfusion. The aim of this study was to evaluate the protective effect of GdCl3 on disturbances of microperfusion in the transplanted liver. METHODS: Landrace pigs were randomly divided into three groups. In the control group (CG; n=6) a mapping of the native liver was conducted. For mapping, the four hepatic liver lobes were named from right to left with A to D and every lobe was divided into three vertical segments (cranial, medial, and caudal). In each of these 12 areas, microperfusion was quantified using a thermodiffusion probe (TD [mL/100 g/min]). The other two groups were considered as transplanted treated group (TTG; n=10) and transplanted nontreated group (TnTG; n=10). The TTG received an infusion of 20 mg/kg GdCl3 intravenously 24 hours before organ harvesting. Then standardized orthotopic liver transplantation was performed. In TnTG, standardized orthotopic liver transplantation was carried out without prior GdCl3 injection. In the recipients, the microperfusion of transplanted livers were mapped in both TnTG and TTG, in two different time points (1 hour [n=5] and 24 hours (n=5]) after reperfusion. RESULTS: A significant reduction of macrophages in the TTG livers in comparison to the CG and TnTG livers was observed (P<.05). However, the number of macrophages in CG and TnTG livers showed no significant difference (P>.05). Regarding liver microperfusion, in TnTG, a marked heterogeneity was detected in the livers after reperfusion. Significant differences between liver lobes (horizontal planes; P=.032) and vertical layers of intralobar liver parenchyma (P=.029) were observed. The same pattern was seen in TTG livers after reperfusion and a significant difference between horizontal (P=.024) and vertical layers (P=.018) of liver tissue were observed. Comparing intralobar regional flow data between vertical planes 24 hours after reperfusion still showed a prominent variation of hepatic tissue perfusion in TnTG livers (P=.028). Within the same horizontal layers, no significant differences between lobes were measured anymore (P=.16). Contrary to TnTG, in TTG, a homogenous pattern of regional liver tissue perfusion was recorded 24 hours after reperfusion. Comparison of TD data on the liver regions showed no significant microperfusion differences in either horizontal (P=.888) or vertical (P=.841) layers. CONCLUSIONS: Application of GdCl3 resulted in a significant reduction of Kupffer cells. Twenty four hours after transplantation microperfusion showed a homogeneous pattern, which constituted an earlier and better recovery of the transplanted liver. Therefore, destruction of Kupffer cells reduced ischemia-reperfusion injury and seemed to be responsible for the early recovery of microperfusion disturbances and thus for an improvement of graft function.