RESUMO
BACKGROUND: Although anorectal transplantation is a challenging procedure, it is a promising option for patients who have completely lost anorectal function or in whom it failed to develop, as in congenital malformations. The paucity of animal models with which to test functional outcomes was addressed in this study of anorectal manometry in rats. METHODS: Wistar rats were assigned randomly to four groups: orthotopic anorectal transplantation, heterotopic transplantation, sham operation, or normal control. Bodyweight and anal pressure were measured immediately before and after operation, and on postoperative days 7 and 14. ANOVA and Tukey's test were used to compare results for bodyweight, anal manometry and length of procedure. RESULTS: Immediately after the procedure, mean(s.d.) anal pressure in the orthotopic group (n = 13) dropped from 31·4(13·1) to 1·6(13·1) cmH2 O (P < 0·001 versus both sham operation (n = 13) and normal control (n = 15)), with partial recovery on postoperative day 7 (14·9(13·9) cmH2 O) (P = 0·009 versus normal control) and complete recovery on day 14 (23·7(12·2) cmH2 O). Heterotopic rats (n = 14) demonstrated partial functional recovery: mean(s.d.) anal pressure was 26·9(10·9) cmH2 O before operation and 8·6(6·8) cmH2 O on postoperative day 14 (P < 0·001 versus both sham and normal control). CONCLUSION: Orthotopic anorectal transplantation may result in better functional outcomes than heterotopic procedures. Surgical relevance Patients with a permanent colostomy have limited continence. Treatment options are available, but anorectal transplantation may offer hope. Some experimental studies have been conducted, but available data are currently insufficient to translate into a clinical option. This paper details functional outcomes in a rat model of anorectal autotransplantation. It represents a step in the translational research that may lead to restoration of anorectal function in patients who have lost or have failed to develop it.
Assuntos
Canal Anal/transplante , Reto/transplante , Canal Anal/fisiologia , Análise de Variância , Animais , Masculino , Manometria , Modelos Animais , Duração da Cirurgia , Pressão , Distribuição Aleatória , Ratos Wistar , Reto/fisiologia , Transplante AutólogoRESUMO
BACKGROUND: Hepatitis B virus (HBV) infection is a major cause of morbidity and mortality worldwide. Chronic hepatitis B infection is associated with an increased risk of cirrhosis, hepatic decompensation, and hepatocellular carcinoma. Our aim is to analyze, through a mathematical model, the potential impact of anti-HBV vaccine in the long-term (that is, decades after vaccination) number of LT. METHODS: The model simulated that the prevalence of HBV infection was 0.5% and that approximately 20% of all the liver transplantation carried out in the state of São Paulo are due to HBV infection. RESULTS: The theoretical model suggests that a vaccination program that would cover 80% of the target population would reach a maximum of about 14% reduction in the LT program. CONCLUSION: Increasing the vaccination coverage against HBV in the state of São Paulo would have a relatively low impact on the number of liver transplantation. In addition, this impact would take several decades to materialize due to the long incubation period of liver failure due to HBV.
Assuntos
Carcinoma Hepatocelular/epidemiologia , Vacinas contra Hepatite B/administração & dosagem , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/epidemiologia , Transplante de Fígado/estatística & dados numéricos , Modelos Teóricos , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/prevenção & controle , Carcinoma Hepatocelular/virologia , Criança , Pré-Escolar , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Vírus da Hepatite B/patogenicidade , Humanos , Lactente , Recém-Nascido , Cirrose Hepática/prevenção & controle , Cirrose Hepática/virologia , Falência Hepática/cirurgia , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/virologia , Pessoa de Meia-Idade , Prevalência , Vacinação , Adulto JovemRESUMO
BACKGROUND: The swine is an essential model for carrying out preclinical research and for teaching complex surgical procedures. There is a lack of experimental models describing anatomical and surgical aspects of total pancreatectomy in the pig. MATERIALS AND METHODS: The experiments were performed on 10 white male swine weighing 27-33 kg. The animals were premedicated with midazolam (0.4 mg/kg, i.m.) and ketamine (4 mg/kg, i.m.). Anesthesia was induced with propofol (1-2 mg/kg, i.v.) and was maintained with propofol and fentanyl (0.3 mg and 0.1 µg/kg/min, respectively, i.v.). The surgical period ranged from 44 to 77 min. The pancreas anatomy, and the main arterial, venous and pancreatic duct anatomy were assessed. RESULTS: The pancreas anatomy was composed of 3 lobes, the 'splenic', 'duodenal' and 'connecting' lobe which is attached to the anterior portion of the portal vein. The splenic artery and the junction of the splenic vein and portal vein were divided. The left gastric artery was dissected and separated from its origin at the splenic artery. The head of the pancreas is disposed in a C shape. The pancreas was dissected and liberated from the right portion of the portal vein and the infrahepatic vena cava. The pancreas was separated from the duodenum preserving the pancreaticoduodenal artery, then we performed the total pancreatectomy preserving the duodenum, common bile duct and spleen. CONCLUSION: Total pancreatectomy with duodenum, bile duct and spleen preservation in the pig is feasible and an important instrument for research purposes and teaching surgical technique.
Assuntos
Diabetes Mellitus Experimental , Modelos Animais de Doenças , Pancreatectomia/métodos , Suínos , Animais , Masculino , Pâncreas/anatomia & histologia , Pâncreas/cirurgiaRESUMO
Liver transplantation increased 1.84-fold from 1988 to 2004. However, the number of patients on the waiting list for a liver increased 2.71-fold, from 553 to 1500. We used a mathematical equation to analyze the potential effect of using ABO-compatible living-donor liver transplantation (LDLT) on both our liver transplantation program and the waiting list. We calculated the prevalence distribution of blood groups (O, A, B, and AB) in the population and the probability of having a compatible parent or sibling for LDLT. The incidence of ABO compatibility in the overall population was as follows: A, 0.31; B, 0.133; O, 0.512; and AB, 0.04. The ABO compatibility for parent donors was blood group A, 0.174; B, 0.06; O, 0.152; and AB, 0.03; and for sibling donors was A, 0.121; B, 0.05; O, 0.354; and AB, 0.03. Use of LDLT can reduce the pressure on our liver transplantation waiting list by decreasing its size by at least 16.5% at 20 years after its introduction. Such a program could save an estimated 3600 lives over the same period.
Assuntos
Sistema ABO de Grupos Sanguíneos/fisiologia , Transplante de Fígado/fisiologia , Doadores Vivos , Incompatibilidade de Grupos Sanguíneos/epidemiologia , Brasil , Feminino , Humanos , Masculino , Pais , Estudos Retrospectivos , Listas de EsperaRESUMO
We propose a mathematical model to simulate the dynamics of hepatitis C virus (HCV) infection in the state of São Paulo, Brazil. We assumed that a hypothetical vaccine, which cost was taken to be the initial cost of the vaccine against hepatitis B exists and it is introduced in the model. We computed its cost-effectiveness compared with the anti-HCV therapy. The calculated basic reproduction number was 1.20. The model predicts that without intervention a steady state exists with an HCV prevalence of 3%, in agreement with the current epidemiological data. Starting from this steady state three interventions were simulated: indiscriminate vaccination, selective vaccination and anti-HCV therapy. Selective vaccination proved to be the strategy with the best cost-effectiveness ratio, followed by indiscriminate vaccination and anti-HCV therapy.
Assuntos
Antivirais/economia , Hepatite C/economia , Hepatite C/prevenção & controle , Vacinas contra Hepatite Viral/economia , Número Básico de Reprodução , Brasil , Análise Custo-Benefício , Hepatite C/tratamento farmacológico , Humanos , Modelos Teóricos , Vacinação/economiaRESUMO
BACKGROUND/AIMS: Hepatic adenoma (HA) is a rare benign tumor of the liver. Tumor resection has been recommended for symptomatic or enlarging HA because of the risk of intraperitoneal, intrahepatic hemorrhage or even the development of hepatocellular carcinoma. From 1989 to 2003 we reviewed the medical records and radiology files of 28 patients with a proved diagnosis of hepatic adenoma. This article summarizes a single-center experience with surgical treatment of hepatic adenoma. METHODOLOGY: 24 patients were female and 4 were male. Twenty-two patients had a history of oral contraceptive use. Abdominal pain was presented in 19 patients and 3 of them had had an acute episode. The mean age was 36.3 years. Preoperative assessment included liver test, ultrasonography and computed tomography in all patients plus technetium (99mTc)-sulfur colloid and 99mTc-labeled DISIDA (dimethyliminoacetic acid) liver scintigraphy (n=19) and magnetic resonance imaging (n=22). RESULTS: Operative procedures included enucleation in 3 patients, two of them associated with hepatic segmentectomy; resection of one or two segments in 14 patients; left and right hemihepatectomy respectively in 7 and 3 patients; right extended hepatectomy in one patient and nonanatomic resection in one patient. There was no postoperative death and the complications were: bile leakage (re-operation) one patient, intraperitoneal abscess (re-operation) one patient, pleural effusion two patients, venous thrombosis one patient and wound infection one patient. CONCLUSIONS: We recommend that since the diagnosis has been well-established both enucleation or anatomically based resections of hepatic adenoma should be performed in all cases mainly in female patients taking oral contraceptives with tumors greater than 3cm for the risk of hepatic hemorrhage or even when malignancy cannot be excluded.
Assuntos
Adenoma/cirurgia , Neoplasias Hepáticas/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
BACKGROUND/AIMS: Variant hepatic anatomy must be recognized and appropriately managed during split-liver transplantation to ensure complete vascular and biliary supply to both grafts. The aim of this study was to demonstrate the importance of an assessment of the hepatic anatomical structures for the purpose of split-liver transplantation. MATERIAL AND METHODS: Human cadaveric livers (n = 60) were obtained during routine autopsies. The cadavers and the livers had to comply with the following requirements: (1) minimum age 18 years, (2) no liver pathology expected from medical history, and (3) no liver pathology noted at autopsy. Resections were carried out en bloc with liver, celiac trunk, left gastric artery, lesser omentum, superior mesenteric artery, and head of the pancreas. The main anatomical structures of the liver as hepatic artery, portal vein, biliary tree, and hepatic veins were dissected and correlated hepatic segments for the application of liver splitting. RESULTS: The right the median, and the left hepatic veins were unique, with in 59 (98.3%), 53 (88.3%) and 46 (76.3%) cases, respectively. The portal vein trunk divided into right and left branches in 59 (98.3%) cases. A median branch appeared in 9 (15.2%) cases and no bifurcation of the portal vein occurred in 1 (1.6%) case. The right and left hepatic ducts were multiple in 47 (78.3%) and 57 (95%) cases, respectively, however, the median, hepatic duct was unique in 16 (26.6%) cases. Examining the intrahepatic distribution of the right hepatic duct, we found 4 branches in 28 (59%) cases (segments V, VI, VII, and VIII) 2 branches in 11 (23%) cases, (segments V and VI) and 2 branches in 8 (17%) cases (segments VII and VIII). Fifty-seven cadavers had multiple left hepatic ducts. The intrahepatic dissection showed that the distribution of the major branches were toward hepatic segments II and III. Three separate branches of the left hepatic duct were found in 11 (19%) cases (segments II, III, and IV). Two intrahepatic ducts coming from hepatic segments V and VI drained separately into the left intrahepatic biliary tree in 1 (2%) case. The arterial supply of the liver was by right and left hepatic artery with only 9 (15%) cases there being median hepatic artery. The right hepatic artery, coming from the superior mesenteric artery, was present in 15 (25%) cases and a left hepatic artery originating from the left gastric artery in only 2 (3.3%) cases. The left hepatic artery had 2 exceptional origins, in 1 (1.6%) case coming directly from the abdominal aorta and in the other from the superior mesenteric artery. The right and left hepatic artery was accessory, in 11 (18.3%) and 2 (3.3%) cases, respectively. The right hepatic artery was dominant in 4 (6.6%) cases. The median hepatic artery was directed to segment IV in 6 (10%) cases and to segment II and III in 3 (4.9%) cases. CONCLUSION: The study showed that the technique of controlled liver splitting for transplantation in 2 recipients is an acceptable method to increase the number of liver allografts. The anatomical and technical details of the splitting procedure are critical for the success of this technique. Good graft function and avoidance of complications depend on each graft having an intact arterial and portal blood supply as well as biliary and venous drainage from all retained liver segments. The absence of a bifurcation of the portal vein is a rare anomaly and would certainly contraindicate a partition.
Assuntos
Hepatectomia/métodos , Transplante de Fígado/métodos , Fígado/anatomia & histologia , Coleta de Tecidos e Órgãos/métodos , Adulto , Cadáver , Veias Hepáticas/anatomia & histologia , Humanos , Procedimentos de Cirurgia Plástica , Doadores de TecidosRESUMO
São Paulo is the first Brazilian state to perform liver transplantation in 1968. Since then the recipient waiting list has increased; now approximately 150 new cases per month are referred to the single list at the central organ procurement organization. Official data have shown 37.3 monthly deaths on the waiting list in the state of São Paulo. The number of liver transplants has increased after the creation of São Paulo transplant notification centers but are insufficient to deal with the increasing waiting list. The aim of this study was to demonstrate the performance of our state liver transplantation program and analyze when the number of liver transplantations will meet our waiting list demand.
Assuntos
Transplante de Fígado/estatística & dados numéricos , Listas de Espera , Brasil , Humanos , Funções Verossimilhança , Fatores de Tempo , Obtenção de Tecidos e ÓrgãosRESUMO
The major indication for pancreas or islet transplantation is diabetes mellitus type I. This process has to supply the insulin necessity keeping glucose under control. We have studied isogenic islet transplantation on the rat (WAG-RT1u) liver. The method of isolation and purification of the islets obtained 2.834 +/- 551.64 islets with purity of 83 +/- 2.45%. Diabetes was induced by streptozotocin and seric glucose prior transplantation was 35 mmol/L. The islet transplantation of 2.834 +/- 551.64 islets in the rat liver has normalized glucose test from 9.62 +/- 2.65 mmol/L 10 days after transplantation to 7.43 +/- 0.27 mmol/L later in the follow-up (P < 0.05). The median survival time of the islets was 73 days. In conclusion both the method of isolation and purification of the islets and islet transplantation was effective in the control of the diabetes induced by streptozotocin with median survival time of both islet and rat more than 73 days when rats were sacrified.
Assuntos
Separação Celular/métodos , Diabetes Mellitus Experimental/terapia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Animais , Glicemia/análise , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pancreatectomia/métodos , Ratos , Ratos Wistar , Estreptozocina , Transplante IsogênicoRESUMO
The authors comment upon the importance of the hepatic wedged venous pressure for the appraisal of the circulatory conditions of the portal system, mainly in cirrhotic patients. Wondering about the irregular results obtained in the study of schistosomotic portal hypertensive patients by occlusive catheterization and with the use of an occlusive balloon catheter, noted the scarcity of angiographic studies on the subject in this pathology. Present the angiographic aspects that were obtained from patients with schistosomotic portal hypertension complicated by digestive bleeding, by means of injecting the contrast material into a hepatic vein of the right hepatic lobe via a loosely introduced catheter. Those radiological aspects were distributed in two categories: 1) type I-presenting variable sinusoidal filling. Presence of anastomotic intraparenquimatous communications with or without calibrous anastomotic veins between the hepatic veins, 2) type II-presenting no sinusoidal filling. Presence of multiple anastomotic communications of varied calibers between the hepatic veins. Commenting the difficulty of assessing the wedged pressure in patients with schistosomotic portal hypertension because of the easy communication between the hepatic veins, the authors point out that the measured pressure, in all the cases, will be that of the opposite hepatic vein. That pressure, in this pathology, might represent the sinusoidal resistance (when present) between hepatic veins, instead of relating to the portal vein. Suggestion is made that the measure of the wedged hepatic pressure, in patients with schistosomotic portal hypertension, be appraised considering the angiographic aspects of the hepatic veins.