The effect of thoracic epidural analgesia on brain tissue oxygenation in thoracic surgery operations with single-lung ventilation

Objectives: The aim of this study was to investigate the effects of thoracic epidural analgesia (TEA) on brain tissue oxygenation in thoracic surgery operations performed single lung ventilation (SLV) with the near infrared spectroscopy (NIRS) method. Materials and method: In this prospective, observational study, fifty patients aged between 18 and 65 years in the American Society of Anesthesiologists (ASA) I-III risk class, who would undergo thoracic surgery with the application of SLV, were included in the study. Patients were divided into two groups: TEA (n=25), with TEA applied, and Control (n=25), with TEA not applied. The primary outcome measure was cerebral regional oxygen saturation (ScO₂) values to be measured by NIRS throughout the operation. Results: The results were statistically evaluated, and when the demographic data of both groups were compared, no statistically significant difference was found (p>0.05). A statistically significant difference was found in the evaluation of the difference scores and percent change scores calculated between the ScO₂ measurement value in the T1 time period, the other measurement times T1-T2, T1-T3 difference scores in the control group were found to be statistically significantly lower (p=0.011, p=0.024, respectively). Conclusion: The results of this study are that TEA performed for analgesia has no effect on cerebral oxygen saturation (ScO₂) and hemodynamics during SLV during the intraoperative period.