Effects of different preoxygenation strategies on dynamic thiol-disulfide homeostasis and blood gas parameters in patients undergoing laparoscopic cholecystectomy.

Abstract

Background: Although oxygen is critical in anesthesia, high-concentration exposure, even for short periods during preoxygenation, may contribute to oxidative stress. In the context of perioperative care optimization, minimizing unnecessary oxidative burden is essential for patient safety. This study investigated the acute effects of standard versus rapid preoxygenation strategies on thiol-disulfide homeostasis and blood gas parameters in patients undergoing laparoscopic cholecystectomy.

Materials and methods: This prospective observational study enrolled 62 ASA I-II patients scheduled for elective laparoscopic cholecystectomy. Patients received 100% O₂ via standard preoxygenation using a tight-fitting face mask for 3 min (Group 1) or rapid preoxygenation consisting of eight deep breaths over 30 s to 1 min (Group 2). Blood samples were collected at four perioperative time points: before preoxygenation (T0), after preoxygenation (T1), post-intubation (T2), and at surgery end (T3). Thiol-disulfide homeostasis was evaluated biochemically; blood gas analyses were performed immediately.

Results: Group 1 showed a significant decline in total thiol levels and a trend toward increased disulfide levels, indicating elevated oxidative stress. Group 2 exhibited more stable thiol-disulfide dynamics. Blood gas analysis revealed greater acidosis, elevated lactate, and increased pCO₂ in Group 1, while Group 2 demonstrated more favorable acid-base and metabolic profiles. Importantly, these effects were observed despite longer surgical durations and higher smoking rates in Group 2, highlighting the potential of optimized preoxygenation to improve perioperative metabolic stability.

Conclusion: Standard preoxygenation was found to induce greater oxidative stress and metabolic disturbances compared to rapid preoxygenation. Incorporating rapid preoxygenation into anesthesia induction protocols may enhance perioperative safety by preserving redox balance and reducing metabolic derangements. These results underscore the need to reevaluate current preoxygenation practices, particularly in metabolically vulnerable patients. Further studies should assess long-term outcomes and applicability in high-risk populations.