Changes in regional cerebral tissue oxygen saturation during anesthesia induction in female patients undergoing breast cancer surgery

Abstract Background Although the monitoring of regional cerebral oxygen saturation (rScO 2 ) is widely used for cardiac and non-cardiac surgeries, conflicting reports regarding changes in rScO 2 during anesthesia induction remain. We designed this cohort clinical study to assess precise alterations in rScO 2 and the possible mechanism . Methods This cohort study was designed to examine changes in rScO 2 with anesthesia induced by a target control infusion of propofol from the beginning of anesthesia to 30 minutes after induction in patients undergoing breast cancer surgery. rScO 2 values from the right and left sides of patients’ foreheads were averaged to directly determine cerebral oxygenation from FORE-SIGHT data. Mean arterial pressure (MAP), heart rate (HR), partial pressure of oxygen in arterial blood (PaO 2 ), partial pressure of carbon dioxide in arterial blood (PaCO 2 ), hemoglobin concentration (Hb), and cardiac output (CO) were measured every minute until 30 minutes after anesthesia induction. Results A total of 30 female patients treated between January 2016 and April 2016 were included in this study. The average rScO 2 at 7 minutes was 81.7%, which was higher than the average rScO 2 at baseline (67.3%) and at 15 minutes (68.3%). Average rScO 2 correlated significantly with PaO 2 during the first 7 minutes of anesthesia induction. Conclusion During anesthesia induction, changes in rScO 2 , which increased to a peak value at 7 minutes, may be correlated with increases in PaO 2 , and the return of rScO 2 to baseline at 15 minutes may have occurred due to flow-metabolism coupling and balancing between white matter and gray matter.