Australia & New Zealand Society of Vascular Surgeons

Background Studies consistently show that the tissue damage caused by surgical trauma can evoke diffuse changes in hormonal and metabolic activity reflecting activation of the two-principle stress axis. The surgical stress response is believed to be a contributing factor to the development of non-specific post-operative complications. Purpose The purpose of this study was to assess and compare intra-operative neuroendocrine responses in two groups of patients; those undergoing open abdominal aneurysm repair (OAR) and those undergoing endovascular aneurysm repair (EAR). Methods Fifty patients who underwent OAR (n=33) or EAR (n=17) were studied. A 24-hour urine save was undertaken in the week prior to admission and again at the commencement of anaesthetic induction to measure cortisol, adrenaline and noradrenaline. Results Demographic analysis of the two groups showed that there were no significant differences in age, gender, comorbidities or ASA classification. Significant increases (p .001) in cortisol and adrenaline from baseline to surgery occurred in all patients. Controlling for baseline neuroendocrine measures, significant differences between the groups were found for measure of intra-operative cortisol [F (2, 47) = 7.55, p = .008] and adrenaline [F (2, 47) = 4.79, p = .03]. Cortisol and adrenaline responses were greater in patients undergoing OAR, by comparison to the less invasive EAR. Conclusion Endovascular AAA repair appears to be associated with a reduction in the intra-operative neuroendocrine response, compared to open repair. This reduction in the physiological stress response may have benefits regarding the incidence of postoperative mortality and morbidity.