Efeito do clampeamento aórtico no estresse oxidativo e na função renal durante cirurgia aórtica minimamente invasiva: estudo experimental em porcos

• Ano de defesa: 2016
• Autor(a) principal: Jaldin, Rodrigo Gibin [UNESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Vascular deseases; Abdominal aortic aneurysm; Laparoscopy; Endovascular procedures; Histology; Doenças vasculares; Aneurisma de aorta abdominal; Cirurgia video-assistida; Laparoscopia; Procedimentos endovasculares; Colite isquêmica; Cólon; Histologia
• Link de acesso: http://hdl.handle.net/11449/141496

Context: Infrarenal aortic cross-campling and surgical trauma are associated with hemodynamic and oxidative alterations that may impair postoperative renal function. Furthermore, Colonic ischemia is a relatively uncommon but devastating complication of abdominal aortic surgery. Its occurrence and severity is related to operative and anesthetic trauma. Therefore, it is a known complication of all different modalities of treatment of abdominal aortic aneurysm. Objective: To evaluate oxidative stress, hemodynamic disorders, renal injuries and histopathological changes in the left colon fragments of pigs subjected to the experimental model of acute aortic flow interruption, comparing the approaches by laparotomy, endovascular surgery and laparoscopic surgery. Materials and Methods: A total of 30 female pigs weighing 15-30 kg were randomly divided into 3 groups, all of which were subjected, under general ihaling anesthesia, to a 60-minute interruption of abdominal aortic flow by means of different techniques: C Group (n=10), through transperitonial laparotomy; L Group (n=10), through a totally laparoscopic technique; EV Group (n=10), through the endovascular procedures by insufflating the occlusion balloon of the aorta. Blood pressure, heart beat, and water balance intraoperative monitoring was performed and blood samples were collected both before the procedure and 60 minutes after reperfusion. The primary outcomes studied were: bleeding volume, systemic oxidative stress (levels of Malondialdehyde, Reduced Glutathione and Glutathione Peroxidase activity) and renal injuries through histology, Creatinine and Cystatin C levels and by assessing oxidative stress on renal parenchyma. A sample of the sigmoid colon, just above the peritoneal deflection, was collected. These were subjected to histopathologic analysis by H & E and immunohistochemical by Caspase-3. Results: C needed a larger amount of crystalloid replacement. Urine output was significantly higher in the EV group. Body temperature only reduced during the procedure in groups C and L and there was a significant reduction in the mean blood pressure in C after the aorta was unclamped. L presented a lower volume of diuresis in the intraoperative period. Histopathological analysis showed changes in edema type and flattened villi in two animals from L and EV groups. Caspase-3 showed more cells undergoing apoptosis and fewer neurons in the EV group. Conclusion: Body temperature is maintained and there is lower fluid loss in the endovascular pathway. Renal function alterations were more evident in EV and the microstructural injury was more frequent in Groups EV and L. The EV group had more severe colonic ischemia, probably related to greater manipulation with endovascular guide wires and catheters, which could lead to spasms and microembolization in small vessels. Although they are less invasive methods, there were discreet and more pronounced renal injuries in the endovascular and video laparoscopic techniques. The great advantage of the method, with respect to hemodynamic stability during the intraoperative period, is the absence of laparotomy and intra-abdominal manipulation in EV. More studies involving longer periods of ischemia and reperfusion may help elucidate the effects of aortic flow disruption on colonic mucosa.