Comparative Evaluation of Oxidative Stress, Cortisol, Inflammatory Response, and Systemic CO2 Dynamics in Dogs Undergoing Laparoscopic and Open Ovariectomy

Abstract

A key distinction between open and laparoscopic surgery is the use of CO2 insufflation to create pneumoperitoneum and establish the operative field. This study compared the effects of laparoscopic and open ovariectomy (OVE) on plasma cortisol, oxidative stress (OS), systemic inflammation, and systemic CO2 dynamics in healthy dogs anesthetized under a standardized protocol. Thirty-eight healthy female dogs were enrolled in the study and allocated to the laparotomy (LPTOVE, n = 19) or laparoscopic (LAPOVE, n = 19) OVE group. OS was assessed using total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI). Systemic inflammation was evaluated by TNF-α and IL-6 concentrations, whereas systemic CO2 dynamics were assessed using plasma total CO2 (TCO2) and end-tidal CO2 (EtCO2). Blood samples were collected prior to sedation (T0), prior to surgical incision (T1), prior to surgical closure in the LPTOVE group or CO2 desufflation in the LAPOVE group (T2), and 2 h postoperatively (T3). Cortisol concentrations at T2 and T3 were significantly higher in the LPTOVE group than in the LAPOVE group. No significant intergroup differences were observed in TOS, TAS, OSI, or TCO2. In the LPTOVE group, TOS significantly decreased at T3, whereas in the LAPOVE group, TOS mildly increased at T1 and OSI significantly decreased at T2. No measurable TNF-α or IL-6 concentrations were detected at the evaluated time points. EtCO2 levels were higher in the LAPOVE group at the end of surgery. These findings suggest that laparoscopic OVE was associated with lower perioperative cortisol concentrations, while systemic redox status, TNF-α and IL-6 concentrations, and carbon dioxide-related parameters remained largely comparable between surgical approaches.