EEG fractal dimension combined with burst suppression ratio as a measure of depth of anesthesia

Abstract

This paper proposes an alternative index for the monitoring of depth of anesthesia. The study was carried out on 6 EEG recordings acquired during surgery under general anesthesia. Induction was provided by propofol, anesthesia was then maintained either with propofol or with sevoflurane under BIS control. The proposed FDSR parameter, combination of Higuchi’s fractal dimension and burst suppression ratio, is able to distinguish among different clinical states and detected two episodes of intraoperative awareness not highlighted by BIS. Moreover, due to its low computational complexity, FDSR is more suitable than BIS for real-time implementation. In conclusion, FDSR is a promising index for the monitoring of depth of anesthesia and the reduction of the incidence of intraoperative awareness.