Liver cirrhosis on the colonic anastomotic healing in rats / Cirrose hepática na cicatrização de anastomose intestinal em ratos

PURPOSE: To investigate the effects of cirrhosis on colonic anastomosis healing in rats. METHODS: Fifty five Wistar male rats were used (23 in the control group and 32 in the cirrhosis group). On the first day of the procedure, the rats in the cirrhosis group underwent double ligation and folding of the common bile duct to induce liver cirrhosis, and the control rats underwent a laparotomy and intestinal manipulation. On the fourteenth and thirty-fifth days, all of the animals were biochemically assessed for serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, bilirubin, total protein, and albumin and for liver histopathology. On the thirty-fifth day, cirrhosis was confirmed. On the twenty-eighth day, all of the animals were subjected to left colon transection and anastomosis. On the seventh day after the colonic anastomosis, the rats were sacrificed and macroscopically evaluated for dehiscence. The region of the colonic anastomosis was removed and subjected to hydroxyproline content measurement, conventional histology, and the immunohistochemical determination of vascular endothelial growth factor (VEGF) and matrix metalloproteinase type 1 (MMP 1). RESULTS: The biochemical and histopathological examinations confirmed cirrhosis in all of the animals in the cirrhosis group. More deaths occurred after anastomosis in the cirrhosis group (5/25) than in the control group (0/21), and anastomotic dehiscence was more frequent in the cirrhosis group (8/25) than in the control group (0/21). The average hydroxyproline concentration was lower in the cirrhosis group than in the control group. The immunohistochemical studies showed that the average VEGF expression in the cirrhosis group was lower than in the control group, and the average MMP1 expression was higher in the cirrhosis group.(AU)

OBJETIVO: Investigar os efeitos da cirrose hepática na cicatrização de anastomose intestinal em ratos. MÉTODOS: Este estudo avaliou o efeito da cirrose hepática na cicatrização de anastomoses em ratos. 55 ratos Wistar machos foram utilizados (23 controles e 32 no grupo cirrose). No primeiro dia os ratos do grupo cirrose for submetidos à dupla ligadura e enovelamento do ducto hepático comum para indução de cirrose e os ratos controles foram submetidos à laparotomia e manipulação das alças intestinais. No dia 14 e 35, todos os animais foram avaliados bioquimicamente para dosagem sérica da alanina aminotransferase (AST), alanina aminotransferase (ALT), fosfatase alcalina, bilurrubinas, proteínas totais, albumina e histologia do fígado. No dia 35 a cirrose foi confirmada. No dia 28 todos os animais foram submetidos à colectomia esquerda e anastomose. 70 dias após anastomose os ratos foram submetidos à eutanásia e foram avaliados macroscopicamente a procura de deiscência. A região da anastomose colônica foi removida para dosagem de hidroxiprolina, histologia convencional e imunohistoquímica para determinação do fator de crescimento endotelial vascular (VEGF) e metaloproteinase tipo 1 (MMP 1). RESULTADOS: A análise bioquímica e histológica confirmou a cirrose em todos os animais do grupo cirrose. Óbito ocorreu em maior freqüência após a anastomose no grupo cirrose (5/25) se comparado com grupo controle (0/21), e a deiscência da anastomose foi mais freqüente no grupo cirrose (8/25) se comparado com controle (0/21). A concentração média de hidroxiprolina foi menor no grupo cirrose se comparado com grupo controle. A análise imonuhistoquímica mostrou que a expressão VEGF no grupo cirrose foi menor que no grupo controle e a expressão média da MMP1 foi maior no grupo cirrose.(AU)

Técnicas de sutura do tubo digestivo em plano único total, em jejuno de cães: pontos de Gambee com nós atados na serosa versus pontos totais atados no lume, sobre a mucosa

PURPOSE: To compare two types of single layer thru-and-thru sutures of the digestive tract: Gambee's stitches with knots fastened in the serosal surface versus simple stitches knotted in the intestinal lumen, under the mucosa. METHODS: Six male mongrel dogs were operated weighing between 7 and 12 kg, anesthetized with sodic pentobarbital to 30 mg/kg. Transverse section of the jejunum was accomplished, to 30 cm of the angle of Treitz, followed by end-to-end anastomosis with interrupted single layer Gambee's stitches fastened in the serosal surface in the anterior half-part of the anastomosis and simple stitches knotted in the viscous lumen, under the mucosal layer, in the posterior half-part of the anastomosis. After slaughter at the 7th postoperative day the peritoneal adhesions were analyzed in the suture line by a score and macroscopic and microscopic analysis were made. RESULTS: Peritoneal adhesions were equivalent in both types of sutures. The intestinal loop showed good serosal regeneration at the suture line. Under microscopy view, residuals acute inflammatory phenomena remain in both sutures. Sparse focus of ischemic necrosis of the mucosa was observed along the suture line, in both types of sutures. Realignment and regeneration of the layers were present along the entire perimeter of the anastomose. In the morphometric analysis, the neutrophils, the macrophages, the fibroblasts and the collagenous fibers were equivalent in number in the two compared half-perimeters of the anastomose. CONCLUSION: The repair of the digestive tract in the anastomotic area after single layer sutures by the technique of Gambee is made in a similar way, despite of special Gambee's stitches or simple total sutures have been used. In that way, it is indifferent the use of both suture type here studied, depending exclusively on the surgeon's preference.

OBJETIVO: Comparar a sutura do tubo digestivo em plano único com pontos totais simples versus pontos especiais de Gambee. MÉTODOS: Foram operados seis cães machos, sem raça definida, pesando entre 7 e 12 kg, anestesiados com pentobarbital sódico a 30 mg/kg. Foi realizada secção transversa do jejuno, a 30 cm da flexura duodenojejunal, seguida de anastomose término-terminal com a técnica de sutura em plano único total descrita por Gambee, sendo a metade anterior da anastomose suturada com nós atados na superfície serosa e a metade posterior com nós atados sobre a camada mucosa, no lume do órgão. Foram utilizados pontos simples separados de polipropileno monofilamentar azul 4-0, pré-montados em agulha de 2 cm (3/8 de círculo), intervalados de 3 mm. No 7º dia pós-operatório os animais foram sacrificados e necropsiados. Foram analisadas as aderências na linha de sutura mediante um escore e feita análise macroscópica e microscópica , inclusive histometria. RESULTADOS: As aderências peritoneais se equivaleram em ambas as faces da anastomose.O exame macroscópico da linha de sutura mostrou boa regeneração serosa. Na microscopia observava-se permanência de fenômenos inflamatórios agudos em ambas as suturas. O realinhamento, a reestruturação e a regeneração das camadas foram adequadas em todo o perímetro da anastomose. Na morfometria, os polimorfonucleares, os macrófagos, os fibroblastos e as fibras colágenas se equivaleram nas duas metades comparadas da anastomose. CONCLUSÃO: A reparação do tubo digestivo na região anastomótica em plano único total pela técnica de Gambee se faz de forma similar, quer tenham sido utilizados pontos de sutura especiais de Gambee ou pontos totais simples. Dessa forma, é indiferente a utilização de um ou de outro tipo de sutura aqui estudado, dependendo exclusivamente da preferência do cirurgião.

Evaluation of the cicatrization of left colon anastomoses in the presence of peritonitis: an experimental study on rats

To monitor the evolution of anastomoses performed on the distal colon in a situation of experimental peritonitis, 37 Wistar-Tecpar male rats aged 114 to 130 days and weighing on avarage 298 g were divided into two lots: group S (control, N = 18) and group P (experimental, N = 19). P rats were submitted to laparotomy and peritonitis was induced by perforating the cecum with a needle, and S rats were only submitted to manipulation of the cecum. Twenty-four hours later animals were resubmitted to laparotomy and distal colectomy was performed 1.5 cm to the peritoneal reflection. End-to-end anastomosis was performed on a single extramucosal plane using 8 separate stitches with 5-0 polypropylene sutures. The anastomoses were checked on the 3rd and 7th postoperative day. Upon opening the peritoneal cavity, the presence of alterations such as peritonitis or abscesses, adhesions, organs involved, fistulas or dehiscences was reorded. A 4.0 cm segment of the colon containing the anastomosis was resected and rupture pressure was measured. Epithelialization of the mucosal wound was evaluted and the material was studied histopathologically for inflammatory reaction and scar condition. Upon relaparotomy, peritonitis was detected in all P animals and fibrin was observed in the cavity of all animals. Adhesions were present in 2 groups, without significant differences between them. Mean rupture pressure was 108.7 mm Hg in group S and 112.0 mm Hg in group P on the 3rd day and 205.0 mm Hg in group S and 206.6 mm Hg in group P on the 7th day, with no significant difference between groups. Microscopic evolution was similar in the two groups. These results permit us to conclude that peritonitis induced by this method does not modify the healing process of distal colon anastomoses in rats.

The relationship between suture number and the healing process of end-to-end arterial anastomosis

In spite of the grate experience accumulated in vascular repairing, the ideal number of sutures for vascular anastomosis remains controversial. It is generally thought that the more stitches applied in a vascular anastomosis, the lesser resistant the anastomosis will be. The purpose of this study was to test this hypothesis in 20 rabbits, in which both carotid arteries were cross sectioned and repaired by end-to-end anastomosis with 8 interrupted sutures in one side (G1) and 16 in the other side (G2). After 3 and 15 days, the animals were randomly allocated for tensile strength, hydroxyproline determination (7 animals) and for histologic analysis of the anastomosis (3 animals). Conventional staining procedures (hematoxylin-eosin and Masson methods) and the picrosirius red polarization (PSP) technique for collagen type determination were used. From 3 to 15 days, the tensile strength increased in both groups, from 265.0±-44.4g to 391.2±-49.0g in G1 and from 310.0±-71.5g to 348.7±-84.0g in G2 (p 0.005), with no statistical difference between the groups in each period of study. The hydroxyproline content, expressed as hydroxyproline/protein ratio, varied from 0.04±-0.01 to 0.05±-0.02 in G1 and from 0.05±-0.01 to 0.05±-0.02 in G2, with no significant difference between periods and groups. The histology showed similar inflammatory and reparative aspects in both groups. In both groups and periods the PSP technique demonstrated predominantly type I collagen in relation to type III collagen in the anastomosis. We concluded that even doubling the number of stitches, the healing process and strength did not change in the arterial anastomosis.

Estudo comparativo de anastomoses colorretais com anel biofragmentável e com grampeador em cães submetidos à irradiação gama pré-operatória

PURPOSE: To compare the early results of colorectal anastomosis with the biofragmentable ring and with stapler after preoperative gamma irradiation with a 500 cGy single dose. METHODS: Forty beagle dogs were distributed in 2 groups of 20 animals submitted or not to preoperative gamma irradiation and named test(II) and control (I) groups respectively. Two subgroups of 10 animals were created: group A in which the biofragmentable ring was used and group B in which the stapler was used. The animals were submitted to full division of the large bowel at the rectosgmoid junction and the intestinal tube has been reconstructed by one of the two techniques randomly assigned. In the seventh postoperative day the animals were killed and histological specimens were collected for macro and microscopic analysis. RESULTS: Two deaths occurred before reoperation: one in the biofragmentable anastomosis group and the other in the stapler anastomosis group, due to generalized peritonitis. Adhesions and wound infection have occurred equally in all groups. The standard histological analysis and computorized morphometric study showed no significant differences between the groups. CONCLUSION: The early results of the two anastomosis technique under risk conditions were alike.

OBJETIVO: Comparar os resultados precoces entre anastomoses colorretais realizadas com anel biofragmentável e com grampeador circular após irradiação pélvica. MÉTODOS: Foram utilizados 40 cães beagle, em dois grupos de 20 animais, submetidos ou não à irradiação gama pré-operatória, com dose única de 500 cGy. Cada grupo foi dividido em dois subgrupos de dez animais, sendo denominado A o grupo em que se utilizou o anel biofragmentável e B aquele em que se empregou o grampeador. Os animais foram submetidos à secção completa do intestino grosso ao nível da junção retossigmóide, com reconstrução do trânsito sendo efetuada por uma das técnicas, após sorteio. Os animais foram sacrificados no sétimo dia de período pós-operatório. RESULTADOS: Houve dois óbitos antes da reoperação: um em animal do grupo teste, por ruptura da anastomose realizada com anel biofragmentável; outro por peritonite generalizada em animal do grupo controle com anastomose efetuada por grampeador. Aderências e infecções de parede ocorreram de forma similar. A análise histológica convencional e a análise morfométrica realizada por computador das áreas de cicatrização anastomótica identificaram comportamento análogo entre os grupos e subgrupos estudados. CONCLUSÃO: Os resultados precoces das técnicas empregadas para anastomose intestinal foram semelhantes nas condições de risco estudadas.