Effects of High-concentration Oxygen Inhalation during Cesarean Section with Spinal Anesthesia on Lipid Peroxidation, Oxidant and Antioxidant Systems

Abstract

Objective: The benefit of supplemental oxygen during elective Cesarean section under regional anesthesia is controversial. Methodology: In this study, parturients were randomized two groups, to breathe either room air (air group, inspired oxygen fraction 21%) or oxygen at a flow rate of 6 L.min-1 (oxygen group, inspired oxygen fraction 40%) by nasal cannula. At delivery, a segment of umbilical cord was isolated using double clamps before the infant's first breath and umblical vein blood samples were obtained. After then, 5th min of oxytocin infusion, a sample of maternal blood was obtained for analysis. The remainder of the sample was centrifuged at 4400 rpm for 4 min and the plasma was stored at -70 degrees C for subsequent batch analysis for 8- i soprostane, TOS, TAC. Oxidation Stress Index (OSI) was assessed as the percentage ratio of TOS level to TAC level. Results: There were significant differences in maternal oxygenation but not neonatal oxygenation in supplemental oxygen group. The parameters indicating lipid peroxidation (8-isoprostane concentration) and oxidative stress (TOS, TAC, OSI) in maternal and umblical blood were higher in FiO(2) supplementation group but this increase was not significant. Conclusions: Although supplemental oxygen increased maternal oxygenation, fetal oxygenation did not changed. Breathing supplemental oxygen did not increased the parameters indicating lipid peroxidation and oxidative stress in maternal and umbilical cord blood in healthy women having elective cesarean section under spinal anesthesia. Consequently, breathing supplemental oxygen does not have a significant effect on neonatal wellbeing and is unnecessary in healthy women undergoing elective Cesarean section under spinal anaesthesia.