Evaluation of the immune-endocrine response in surgical patients undergoing desflurane-nitrous oxide or desflurane-nitrous oxide free anaesthesia

Mariana Gobbo Braz, Nayara Micarelli de Arruda, Flávia Ribeiro Nogueira, Kátina Meneghetti de Souza, Leandro Gobbo Braz, José Reinaldo Cerqueira Braz
Department of Anesthesiology, Botucatu Medical School, São Paulo State University (UNESP), Professor Mário Rubens G. Montenegro Av., Botucatu, SP, Brazil. 18618-687. 
Background and Goal of Study: Literature is scarce in relation to possible effects of the association between the gaseous nitrous oxide (N2O) and the halogenated desflurane on the immune-endocrine response in surgical patients. We hypothesised that N2O associated with desflurane would increase the inflammatory and neuroendocrine effects when compared to the use of desflurane alone. The primary aim of this study was to compare the effects of anaesthesia maintained with desflurane associated or not with N2O on inflammatory and neuroendocrine hormone biomarkers, and the second aim was to assess whether there were changes in the respective biomarkers within each group during and after surgery. 
Materials and Methods: After approval from the local Ethical Committee and Brazilian Clinical Trial Registry, this prospective study was conducted in 40 ASA physical status I adults who underwent septoplasty and were randomly assigned in two groups to receive desflurane anaesthesia (n = 20) or desflurane anaesthesia associated with 60% of N2O (n = 20). Blood samples were collected before anaesthesia (baseline), 1.5 h after anaesthesia induction, and on the first day after surgery. Inflammatory markers (interleukins IL-6, IL-8 and IL-10, and high-sensitivity C-reactive protein – hs-CRP) and adrenocorticotropic (ACTH), cortisol and prolactin hormones were analysed in serum while gene expression of pro-inflammatory markers (NF-κB, IL-6 and COX-2) were evaluated in peripheral blood cells by real-time quantitative polymerase chain reaction.
Results and Discussion: There were no significant differences between groups regarding demographic, intraoperative, inflammation and hormonal data (P > 0.05). The results also showed that in both anaesthetic techniques there were significant increases of systemic intra-operative prolactin and post-operative pro-inflammatory mediators IL-6 and hs-CRP. 
Conclusions: Contrary to our hypothesis, N2O associated with desflurane did not impair the inflammatory and endocrine response when compared to patients who received only desflurane. Thus, both anaesthetic techniques were similar regarding immune-endocrine effects by leding to prolactin change during anaesthesia and pro-inflammation status after surgery in healthy patients who underwent minimally invasive surgery. 

Acknowledgements: FAPESP (grant #2013/16842-0) and CNPq supported this study.

04 / Evaluation of the immune-endocrine response in surgical patients undergoing desflurane-nitrous oxide or desflurane-nitrous oxide free anaesthesia
