Maria de Lourdes Pessole Biondo-Simões

Correlação entre o fluxo sangüíneo intestinal e a cicatrização de anastomoses colônicas: estudo experimental em cães

Laser Doppler Flowmetry in the medical field provides a progress to quantify blood flow. Colonic anastomosis deishence is sometimes associated with hipovolemic shock. The aim of the present study was to correlate the bowel blood flow alterations due to hypovolemic shock and colonic anastomosis healing. Sixteen dogs were submited to colonic anastomosis. In eight of them shock was induced. The blood flow was measured during all surgical procedure except when anastomosis was being performed. Also cardiac frequency and medium arterial pressure were measured during all the experiment and hematocrit was obtained from three different samples. On the 7th post operative day, dogs were reoperated to evaluate the anastomosis. Fifteen centimeters of colon with the anastomosis were resected to access anastomosis rupture pressure, colagen densitometry and histology features. Infection complication were twice higher in the shock group compared to the non-shock group. There was no statistic difference between groups relating to rupture pressure. However the total colagen concentration was higher in the non-shock group and histologic study showed better healing parameters in the non-shock group. We concluded that low intestinal flow provides worse anastomosis healing, a high incidence of clinical complications, low colagen concentration and a low standard histology parameters.

Colite do cólon excluso: modelo experimental em ratos

In 1981 Glotzer et al. described a kind of proctocolitis, limited to a segment of colon, excluded from the fecal stream, with pathological features similar to the ulcerative colitis. The purpose of the present study was to establish a experimental model in order to evaluate the pathologic alterations of the colonic mucosa, excluded from the intestinal transit. Thirty five PUCPR Wistar male rats, with a mean age of 120 days were allocated in 4 groups. Under ether anesthesia, the animals were submitted to a 0,5cm resection of the left colon. A proximal terminal colostomy was performed and the distal rectal stump was closed. The excluded segment of the bowel was evaluated macro and microscopically a week (A group), 2 weeks (D group), 4 weeks (B group) and 8 weeks (C group) after the operation. The inflammatory reaction, collagen concentration and changes in the goblets cells were analyzed .Mo was considered the features of the excluded colon seen at the beginning of the experiment and Mf was these features seen at the end of experiment. When we compared these two different phases of the experiment, we verified that a mild acute and cronic inflammatory reaction was present in all of the groups. Ulcers were seen in 11 colons (p=0,0010) and they were not related to the exclusion phase. A significant reduction in the thickness of the colonic wall was observed in all the specimens. In Mo, the mature collagen (type I) was the predominant one (p=0.008) whereas in Mf, the immature collagen ( type III) was the predominant one (p=0.008). Reduction of total collagen, loss of collagen type I and the increase of collagen type III were constant. There was no significant change in the percentage of area occupied by the goblets cells. It was concluded that in rats, the exclusion of the distal colon by colostomy of up to 8 weeks, determines: colon atrophy and the occurrence of superficial ulcerated lesions with low-level inflammatory reaction.

Análise das complicações pós-operatórias em decolostomias

The aim of the present study was to analyse the complications seen in patients who underwent colostomy and reconstruction of the intestinal tract Fifty six patients, with a mean age of 39 years) were studied _ 37were men and 19 women. The indications for colostomy were: gunshot wounds (35%), perforated diverticulitis (12.5%) and colorectal cancer (12%). Terminal colostomy on the sigmoid colon was the most frequent ostomy performed (71,4%). The mean time for colostomy closure was 5.5 months. In 85.7% of the patients transit reconstruction was performed through an end to end anastomosis, using mechanical suture (in 5 patients), hand sewing (in 51 patients). The rate of complications observed was 25%. The most frequent complications were abdominal wall wound infection (35,7%), fistulas (28.6%) and haemorrhage (21.4%). It was concluded that reconstruction of the intestinal tract carries a high risk of complication and infection continues to be a great challenge in these procedures.

A influência da nicotina na densidade de colágeno em cicatrizes cutâneas, em ratos

OBJECTIVE To study the inflammatory reaction and deposition of collagen in the healing of cutaneous injuries under the influence of nicotine. METHODS The scars of abdominal injuries in rats were analyzed, which had been treated with nicotine, 2 mg/kg/d, and compared with those of control rats. Treatment was begun seven days prior to operation and was maintained for seven or fourteen days after surgery. The histological cuts were stained with hematoxylin and eosin and through the established scores the intensity and type of inflammatory reaction was identified. Histological cuts stained by Sirius Supra red F3BA enabled the identification of the collagen density. RESULTS There was no difference in intensity of the inflammatory reaction after seven days (p=0.165), nor after fourteen days (p=0.684). There was no significant difference in the type I collagen density in the evaluation carried out after seven days (p=0.912) and after fourteen days (p=0,211). The control group had more type III collagen after seven days (p=0.004), but after fourteen days there was no significant difference (p=0.720). Although the total quantification of collagen was higher in the control group, there was no significant difference at any time during this study (p=0.103 after seven days and p=0.549 after fourteen days). CONCLUSION In the scars of the animals treated with nicotine in comparison with the control group, there was no difference in the intensity of the inflammatory process, nor in collagen density.

Influência da peritonite sobre a síntese de colágeno em anastomoses do cólon distal: estudo experimental em ratos

The purpose of the present study was to evaluate the burst strength and the collagen concentration in a left colonic anastomosis when peritonitis was present. Forty Wistar male rats were used, with a mean age of 120 days and a mean weight of 302 g. The animals were allocated in two groups of 20 animals each: a control group and an experimental group. Under ether anesthesia, the rats of the experimental group were submitted to a laparotomy and the abdominal sepsis was induced according to the Wichterman method, while those in the control group were submitted to laparotomy and manipulation of the intestinal segments involved in the experiment. Twenty four hours later, the animals underwent to a new laparotomy and a left colonic anastomosis, with a single layer of polypropilene interrupted suture, 2,0 cm above the peritoneal reflection. On the 3rd and 7th post-operative day, the colonic segment with the anastomosis was resected in order to evaluate the bursting strength . The Red Sirius dye was used to evaluate collagen concentration in the histopathological study. Results showed in both groups an increase in the bursting strength , relating to post-operative day. Collagen concentration was poorer in the peritonitis group on the 3rd and 7th post-operative days (p = 0.000168) (p = 0.0020) respectively. The percentages of collagen I and III were similar on the 3rd post-operative day. On the 7th day, however, collagen type III (p =0.000079) predominated in the peritonitis group. The results above showed that the concentration and maturation of collagen are reduced in a colonic anastomosis performed when peritonitis is present. These alterations does not interfere in the bursting strength.

Effect of streptokinase in the prevention of intra-abdominal adhesions in the rat

O objetivo deste estudo foi determinar o efeito da estreptoquinase, derivada do estreptococo com acao fibrinolitica, na prevencao de aderencias intra peritoneais em ratos. Oitenta animais forma distribuidos em 4 grupos de 20 animais cada. O grupo A (controle) recebeu solucao salina pela via intraperitoneal; o grupo B recebeu estreptoquinase pela via intraperitoneal na dose de 60.000 unidades por quilograma de peso diluido em 2 ml de solucao salina; o grupo C recebeu 60.000 unidades de estreptoquinase diluido em 1mililitro (ml) de solucao salina pela via intravenosa e o grupo D recebeu 30.000 unidades de estreptoquinase em 2 ml de solucao salina pela via intraperitoneal e 30.000 unidades de estreptoquinase diluidas em 1 ml de solucao salina pela via intravenosa. Os animais foram submetidos, aleatoriamente, a laparotomia mediana para a colocacao de fios de suturas que induziriam a formacao de aderencias do tipo isquemica de acordo com o modelo de FERRAZ-NETO e col. (1991) modificado, e sacrificados com uma dose letal de eter sulfurico no 3o e no 7o dia de pos operatorio. A estreptoquinase mostrou ser efetiva na prevencaode aderencias quando utilizadas pela via intraperitoneal (p=0,0349) ou quando ministradas simultaneamente pela via intraperitoneal e pela via intravenosa (p=0,0073). A comparacao dos resultados no 3o e do 7o dia de pos operatorio, em um mesmo grupo, mostrou que nao ha diferenca estatisticamente significante, sugerindo que a droga age no inicio do processo de cicatrizacao. Conclui-se que a estreptoquinase e efetiva na prevencao de aderencias quando utilizadas pela via intraperitoneal ou quando se combina a via intraperitoneal com a via intravenosa nas doses utilizadas, em ratos.

Obesity and abdominal wound healing in rats

INTRODUCTION Treatment for obesity essentially has to do with weight loss, which can be achieved through surgical procedures. Despite the considerable rise in the number of such procedures, the relationship between obesity and the healing process has not been totally clarified. PURPOSE To investigate abdominal wound healing in obese Wistar rats on the seventh and fourteenth days following a laparotomy. METHODS Thirty-six Wistar rats were randomly distributed into two groups, the control and experiment group. The control group were fed on either a standard diet for the species and the experiment group were put on a high calorie diet. After 116 days, all the animals were submitted to a laparotomy followed by laparorrhaphy. After euthanasia on the seventh or fourteenth day, fragments of the abdominal wound containing the scar were submitted to histopathological and tensiometric analysis. RESULTS The average weight of the animals from the experiment group was higher than that of the control group (p<0.001). The difference in the resistance of the cutaneous scars was not significant. The aponeurotic scars were more resistant in the control group after seven days (p=0.011) and fourteen days (p=0.040). There was no difference in terms of intensity of the inflammatory reaction and the collagen density was similar in both groups. CONCLUSION In rats, obesity lowered the resistance of the aponeurotic scars but not the skin scars. It did not interfere with the delayed inflammatory response and the collagen density.

Efeitos do uso crônico da dexametasona na cicatrização de feridas cutâneas em ratos

BACKGROUND: Glucocorticoids are believed to hinder healing process, causing decreased cell proliferation, neovascularization and matrix production. OBJECTIVE: To investigate the effects of the chronic use of corticosteroids on skin wound healing. METHODS: After daily injections of dexamethasone (0.1 mg/Kg) for 30 days, an excision was made in the dorsum of rats. Wound healing was evaluated at postoperative days 3, 7 and 14. Scar resistance, collagen density and inflammatory reaction were assessed by histometry. RESULTS: The scars of the dexamethasone-treated group were less resistant to traction in all days (p=0.008) and presented lower collagen density. Collagen III density was affected at all times (p<0.0001) and collagen I density was lower only on day 14 (p<0.0001). The inflammatory cell infiltration was less intense in the dexamethasone-treated group in the first two evaluations (p=0.001 and p=0.016), but there was no significant difference on day 14, (p=0.367). CONCLUSIONS: We observed decreased scar resistance and lower total collagen density in all periods studied. In the beginning of the process, low collagen III density was observed and later collagen type I density was also decreased. Reduced number of inflammatory cells was found in the first two evaluations.

Influência do buflomedil em retalhos cutâneos isquêmicos: estudo experimental em ratos

Vasoactive drugs have been employed in an attempt to increase the viability of ischemic skin flaps. The aim of the present study was to evaluate the effects of the vasoactive drug, Buflomedil, in the prevention of ischemic skin flaps of rats. Twenty male rats were divided into na experimental group B and a control group A. In the animals of group B, 3mg/kg of Buflomedil was given intraperitoneally every 12 hours for 2 days before surgery and for 7 days after surgery. An abdominal skin flap was used as a model, with a cephalic base measuring 9 x 4cm. The viability of the flaps was evaluated with a laser fluxometer in predetermined points in the early pre and postoperative period and on the 7th post operative day Planimetric analysis of the total area of the flap, of the vascularized area, and of the necrotic area were done on the 7th day after the operation. Inferior necrosis of the flap was observed in all of the animals in both groups. The statistical analysis of the results obtained did not show a significant difference in the planimetry between the control and the experimental groups. Fluxometry did not show a significant difference in relation to the median points between the two groups. It was concluded that Buflomedil, in the manner in which it was used in this experiment, does not reduce necrosis in ischemic skin flaps of rats.

A comparative study of the performance of catgut and polyglecaprone 25 sutures in rat abdominal walls, contaminated or not

Comparou-se as suturas realizadas com poliglecaprone e categute na parede abdominal, contaminada ou nao, de ratos. Foram utilizados 40 ratos Wistar Tecpar divididos em dois grupos de 20 designados A e B. Implantavam-se os fios na parede abdominal ventral, com o poliglecaprone a esquerda e o categute a direita. No grupo B inoculava-se na tela subcutânea 1,0ml de solucao padronizada de Staphylococcus aureus no trajeto de cada um dos fios. Praticava-se a eutanasia, em 10 animais de cada grupo, no terceiro e no setimo dia. A parede abdominal ventral, repartida em duas metades, direita e esquerda, era fixada em formalina e encaminhada para estudo histopatologico. O fio de poliglecaprone 25, na presenca ou ausencia de contaminacao da parede abdominal de ratos, apresentou reacao tecidual significantemente menos intensa do que o fio de categute, em ratos.