RESUMO
AIM: This study sets out to test the biocompatibility of titanium clips in liver, in the presence of radiofrequency. Biocompatibility is assessed at various distances from the RF electrode and different points in time. METHOD: It is an experimental study conducted on pigs and makes use of histological changes that occur at the liver-titanium interface in presence of RF to test hypotheses. The titanium clips were modified in high vacuum (10 -5 atm) by heating them at 1000 degrees C and 1150 degrees C. Titanium clips were placed in liver at 0.5, 1.5 and 2.5 cm from RF probe. At 7, 14 and 28 days the inflammation, necrosis and fibrosis were assessed. RESULTS: The histological alterations decrease with the distance of implantation of titanium clips. The inflammation and necrosis nearby the titanium clips decrease in time, but the fibrosis does not increased, as expected. The modified titanium at 1000 degrees C clips cause less necrosis than commercial titanium clips. The moderator role of clip type between distance and cell alteration is empirically supported only for fibrosis and necrosis. The moderator role between time and cell alteration is supported only for inflammation. CONCLUSIONS: Experimental data suggests there are no preferred surgical clips in all situations. The biocompatibility of the titanium clips depends on the distance from the RF probe. The commercial ones prove less damaging if they are placed close to the RF probe (less than 1 cm) and those that were treated at 1150 C have a better bio-compatibility if placed more than 1 cm from RF probe.
Assuntos
Ablação por Cateter , Hepatectomia/instrumentação , Fígado/patologia , Teste de Materiais , Instrumentos Cirúrgicos , Titânio , Animais , Modelos Animais de Doenças , Hepatectomia/métodos , Teste de Materiais/métodos , Sus scrofa , Suínos , Resultado do TratamentoRESUMO
This study describes an experimental model of accessory renal allotransplantation in the big laboratory animal (pig). A total of 24 common-breed pigs were used. All allografts were transplanted in an accessory manner and revascularized at the level of the infrarenal abdominal aorta and inferior vena cava. The urinary drainage was performed either through a nexternal uretheroneostomy at the ipsilateral lumbar region (Group A--n=8) or by internal uretheroneocystostomy (Group B--n=8). All transplants were monitored for 8 days postoperatively using translumbar ultrasound-guided biopsies at 1, 4, 7 days. A total of 16 transplants were performed. 1 ectopic donor kidney was found and transplanted in the same fashion. Mean operative time was 125 minutes, immediate postoperative survival was 100% and at 72 hours, 87.5%. The onset of acute rejection was at day 4, by massive lymphocyte infiltration and was directly correlated with the abrupt decrease of the allograft diuresis in Group A, at day 3. At day 7, the rejection was complete. Both methods of urinary drainage are functional and can be employed. This experimental model is a useful tool for training of the transplant surgeons or for transplantation research. The surgical technique for accessory renal allotransplantation in pig is easy to learn and offers the possibility for allograft monitoring until complete rejection without influencing the receptor health condition.
Assuntos
Transplante de Rim/métodos , Derivação Urinária/métodos , Animais , Cistostomia , Modelos Animais de Doenças , Drenagem , Nefropatias/cirurgia , Sus scrofa , Suínos , Transplante Homólogo , Resultado do Tratamento , Ureter/cirurgiaRESUMO
The aim of this clinical prospective study was the follow up of a nutritional management protocol for children with esophageal atresia and tracheoesophageal fistula for whom the esophageal substitution was performed with left vascularized colon. In this study entered infants aged 3 months to 18 months old with a major nutritional deficit, due to respiratory infections complications, parastomal leaks and accelerated gastrointestinal transit. All infants were underweight, with a single exception, who had no preoperative complications. The patient was enterally fed postoperatively, all the other patients receiving combined enteral and parenteral nutrition for 5-6 days. The enteral nutrition was delivered early through a trans-anastomotic feeding tube. In the 5th-7th day, complete enteral nutrition was obtained. The parenteral nutrition followed our own recipe: a 10% amino-acid mixture, 50% glucose and Ringer plus electrolytes and vitamins. There was a critical transitional stage between the gastric tube feeding and the oral nutrition. These infants have the suction and the deglutition reflexes modified, followed by oral sensory and motor deficits. After the release from the hospital the patients have been surveyed, the oldest reaching now the age of 7. The earlier the reconstruction was performed, the less problems in oral nutrition were encountered.