Comparison of Relevance in Patient Status Index (Psi) And Spectral Edge Frequency (Sef) With End-Expiratory Sevoflurane Concentration (Etsev) During General Anesthesia Surgery

Objective. To investigate the correlation between PSI, SEF and ETSEV in patients undergoing general anesthesia. Methods. In this study, 26 general anesthesia patients (11 males and 15 females, aged 21-70 years, ASA I-III) underwent lower extremity orthopedic surgery were selected. PSI, SEF, and ETSEV were recorded by Sedline brain function monitor and PHILIPS MP20 monitor, respectively, and the difference between SEF-L and SEF-R ΔSEF was calculated. Spearman correlation analysis was used for the correlation between PSI, SEF and ETSEV, and Bland-Altman was used to analyze the consistency of SEF-L and SEF-R. Results. Spearman correlation analysis showed that PSI (r=-0.401, P=0.001), SEF-L (r=-0.705, P=0.000), and SEF-R (r=- 0.635, P=0.000) were all negatively correlated with ETSEV, and SEF was more strongly correlated with ETSEV compared to PSI. Bland-Altman analysis showed that there were 2 points outside the limits of agreement between SEF-L and SEF-R, and SEF-L remained in agreement with SEF-R. Conclusion. Under sevoflurane-maintained general anesthesia, SEF was more responsive to intraoperative depth of anesthesia changes in patients, and left and right brain SEF remained consistent.