Extrahepatic obstruction: definition, classification, ethiology, pathophysiology

A icterícia é um sinal clínico comum a várias condições patológicas. As icterícias obstrutivas ocorrem quando há algum obstáculo ao livre fluxo de bile entre o sítio produtor (hepatócito) e o duodeno e são causadas por drogas, doenças imunológicas, afecções congênitas, parasitas, cálculos ou tumores. Para o cirurgião, as icterícias obstrutivas extra-hepáticas são as mais importantes e podem não cursar com as clássicas elevações enzimáticas. O aumento da pressão ductal e a contaminação da bile têm efeitos deletérios não só para a célula hepática como para todo o sistema imunológico. O benefício da descompressão pré-operatória ainda é objeto de discussão e a completa avaliação pré-operatória pode diminuir as taxas de morbidade cirúrgica.Jaundice is a very common clinical sign in the decorrence of multiple morbid conditions. Obstructive jaundice occurrs when na obstacle disturbs the natural bile flow from hepatocytes to duodenum and it can be caused by drugs, immune diseases, congenital disorders, parasites, stones or tumors. Extrahepatic obstructive jaundices are the most importan for surgeons and sometimes they do not have very tipical elevated enzymes. The intraductal hypertension and bile contamination damage seriously not hepatocytes but all the imunologic system. Preoperative decompression is still causing discussion in literature but a good assessment can prevent surgical complications

Extrahepatic cholestasis: Laboratory and image diagnosis

A investigação das icterícias obstrutivas inicia-se pela história, exame físico e testes laboratoriais. Os métodos de imagens (ultra-sonografia, tomografia computadorizada, ressonância magnética) atualmente são indispensáveis para uma correta avaliação. Outros métodos intervencionistas, como a colangiografia percutânea e endoscópica também desempenham importante papel e possuem indicações precisas. A cintilografia hepatobiliar tem limitado papel na propedêutica desses doentes, mas métodos modernos como a colangio-ressonância podem ocupar mais espaço na medida em que apresentam boa resolução e baixo risco. O sucesso do tratamento cirúrgico das icterícias obstrutivas depende de uma completa avaliação pré-operatória que é possível apenas com a cooperação entre cirurgiões, clínicos e radiologistas. Centros especializados têm sido criados com este objetivo.Initial investigation of obstructive jaundice begins with anamnesis, physical examination and laboratory analysis. Image methods (ultrasound, computed tomography, magnetic ressonance) are indispensable nowadays for a correct evaluation. Other invasive procedures such as endoscopic or percutaneous cholangiography have well defined roles and need precise indication. Hepatic scintigraphy has a limited role but new methods including MRI-cholangiogram are increasingly used ducto great accuracy and low risk. The successful treatment of the jaundiced patient depends on a complete pre-operative assessment from surgeons, physicians and radiologists working together. Especialized units have been created with this aim

Estudo da liberação renal de glicose em coelhos submetidos a hepatectomia total funcional e a infusão de noradrenalina

Orientadores : Luis Sergio Leonardi, Mario Jose Abdalla SaadDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências MédicasResumo: O transplante de figado é, atualmente, um procedimento bem aceito para o tratamento das doenças hepáticas terminais. Após a retirada do figado nativo, inicia-se um período onde o indivíduo permanece sem figado. Esse período se estende até o momento da reperfusão do enxerto e é chamado de período anepático do transplante. Nessa fase, as alterações metabólicas são fteqüentes, e a hipoglicemia, hipoteticamente, deveria ocorrer. No entanto ela quase nunca aparece. A fonte endógena de glicose, durante a fase anepática do transplante de figado, ainda não é conhecida. Com o objetivo de estudar as prováveis fontes endógenas de glicose na ausência do figado (equivalente à fase anepática do transplante de figado), foi criado um modelo experimental de hepatectomia total funcional em coellios anestesiados. A fim de estudar se existe liberação renal de glicose após a hepatectomia, foram cateterizadas a aorta, ao nível da emergência das artérias renais, e a veia renal direita, para collieita de dosagens de glicemias seriadas. Os experimentos-piloto demonstraram a necessidade de se infundir droga vaso ativa (noradrenalina-NAdr) para evitar hipotensão após a retirada do figado. Foram, então, criados dois grupos de animais: grupo 1, com cinco animais submetidos à infusão de NAdr' que tiveram seus figados intactos; e o grupo 2, com quinze animais também submetidos à infusão de NAdr, mas que tiveram seus figados retirados. Os resultados demonstram que, no grupo 2, antes da hepatectomia, as dosagens de glicemias arteriais foram maiores que as venosas e, após a retirada do órgão, esses valores tornaram-se menores. Isso configurou inversão das curvas das glicemias, conforme pode ser visto no gráfico 2. No grupo 1 (animais sob efeito exclusivo de NAdr), as curvas não apresentaram essa inversão. Conclui-se que a inversão das curvas de glicemia, observadas nos animais do grupo 2, não se deve à ação da NAdr e significa liberação renal de glicose após a hepatectomiaAbstract: Nowadays tiver transplantation is a well accepted procedure to treat terminal tiver disease. After the tiver removal takes p1ace there is a period when the tiver is absent. This period, which is called anhepatic period, lasts until the new tiver is reperfused. During this period metabotic changes are frequent and hypoglycemia may hypothetically occurs. However, severe hypoglycemia almost never takes place. It must be stated that the source of endogenous glucose during the anhepatic period of tiver transplantation remains unknown. To study the possible sources of glucose in the absence ofthe tiver -corresponding to the anhepatic phase of tiver transplantation - an experimental model of total hepatectomy in anesthetized rabbits was created. To study the possibility of renal glucose release after hepatectomy the aorta (at the origin of the renal arteries) and the right renal vein were catheterized to measure glucose contento The initial experiments showed the necessity to give a vasoactive drug (norepinephrine) to avoid severe hypotension after tiver removal. Thus, two groups of animais were created: group 1, with five animals, were given norepinephrine infusion without hepatectomy, and group 2, with fifteen animals received norepinephrine and were submitted to total hepatectomy. The results showed that in group 2, before the hepatectomy, the levels of arterial glucose were higher than the venous ones, while, after the procedure the arterial levels became lower than the venous ones. That resulted in an inversion in the ghieemic curves, as one can see in graphic 2. In group 1 the curves did not show this inversion. We conc1uded that the inversion of curves observed in group 2 cannot be explained as just being due to norepinephrine infusion but represents renal glucose release after hepatectomyMestradoMestre em Cirurgi

Renal glucose release in rabbits submitted to total functional hepatectomy and norepinephrine infusion

Aim — To study the possible endogenous sources of glucose in the absence of the liver (equivalent to the anhepatic period of liver transplantation). Material and Methods - A experimental model of total functional hepatectomy in anesthetised rabbits was developed. The aorta and the right renal vein were catheterised in order to collect blood samples to measure glucose contents. The animals were divided into two groups: group 1, 5 animals underwent only norepinephrine infusion; group 2, 15 animals underwent norepinephrine infusion and submitted to total functional hepatectomy. Results - In group 2, before the hepatectomy, arterial glucose levels were higher than venous ones and after the liver removal, the venous levels became higher than the arterial ones. This pattern showed an inversion in the glicemic curves. In group 1 this pattern was not observed. Conclusion - The glicemic curves behavior observed in group 2 is not due to norepinephrine infusion, but represents renal glucose release after total functional hepatectomy.Objetivo — Estudar as prováveis fontes endógenas de glicose na ausência do fígado (equivalente à fase anepática do transplante de fígado). Material e Métodos - Criou-se um modelo experimental de hepatectomia total funcional em coelhos anestesiados. A aorta e a veia renal direita foram cateterizadas para colheita de glicemias seriadas. Os animais foram divididos em dois grupos: grupo 1, com 5 animais submetidos apenas a infusão de noradrenalina e grupo 2, constando de 15 animais também submetidos a infusão de noradrenalina e tiveram seus fígados retirados. Resultados - Demonstram que, no grupo 2, antes da hepatectomia, as dosagens de glicemias arteriais foram maiores que as venosas, e após a retirada do órgão, estes valores se tornaram menores. Isto configurou inversão das curvas das glicemias. No grupo 1 não foi observada essa inversão. Conclusão - Conclui-se que esse comportamento das curvas de glicemia observadas nos animais do grupo 2 não se deve à ação da noradrenalina e significa liberação renal de glicose após a hepatectomia.18318

Aminiotic Fluid And Intrauterine Growth Restriction In A Gastroschisis Fetal Rat Model.

Fetuses with digestive anomalies such as gastroschisis may present intrauterine growth restriction (IUGR) and shortened intestines. The aim of this study was to assess the influence caused by amniotic fluid (AF) in intestinal length and somatic growth in an experimental gastroschisis fetal model at two distinct gestational ages. Fetal rats were operated according to Correia-Pinto on 2 different days of gestation: day 18.5 (group I) and day 19.5 (group II). Each group was divided into three sub-groups: fetuses with gastroschisis (G), control (C) and sham(S). Body measurements and histological analysis were done. Body measurement analysis showed: average body weight (g) in group I was G = 5.32, C = 5.68, S = 5.86; group II was G = 5.32, C = 5.80, S = 5.66. Average intestine weight (g) in group I was G = 0.283, C = 0.238, S = 0.231; group II was G = 0.272, C = 0.231, S = 0.233. Average intestine length (mm) in group I was G = 125, C = 216, S = 209; group II was G = 148, C = 226, S = 226. Histological analysis showed a decrease in the number and size of the intestinal microvillae and a light edema of serosa. Gastroschisis had a direct correlation with IUGR and the time of exposure of the fetuses to AF had no influence on body weight in gastroschisis fetuses but did interfere with intestinal length.20494-

The Incapacity of the Surgeon to Identify NASH in Bariatric Surgery Makes Biopsy Mandatory

Nonalcoholic steatohepatitis (NASH) is a morbid condition highly related to obesity. It is unclear if the macroscopic liver appearance correlates with the histopathologic findings. The goal of this prospective study was to determine the relationship between the intraoperative liver appearance and the histopathologic diagnosis of NASH in morbidly obese subjects undergoing bariatric surgery. We also aimed to determine variables that could predict NASH preoperatively. Consecutive 51 subjects undergoing bariatric surgery without evidence of other liver disease underwent intraoperative liver biopsy. An intraoperative liver visual (macroscopic and tactile examination) was recorded. The liver aspect was compared with the liver histologic findings. Histological assessment was categorized into two groups: NASH and non-NASH (including normal histology and simple steatosis). Clinical and biochemical parameters were obtained from the patient databases and were compared between groups to identify preoperatively predictive factors of NASH. From 51 patients, only one presented totally normal histology. Forty-three (86.2%) presented simple steatosis, and seven (13.7%) were classified as NASH. Clinical parameters were not different between groups. At biochemical analysis, only VLDL cholesterol level was significantly higher in the NASH group (p = 0.037) but yet within the normal range. Association between macroscopic liver appearance and the presence of histological NASH is poor (sensitivity of 14%, specificity of 56%, positive predictive value of 5%, and negative predictive value of 80%). No predictor of NASH was found. Surgeons` evaluation could not identify NASH individuals. Routine liver biopsy during bariatric operations is mandatory to differentiate NASH and nonalcoholic fatty liver disease.19121678168