Comparison of PSD of HRV and DFA of EEG during general anesthesia

To investigate the effect of PSD of HRV and DFA of EEG on autonomic nervous system activity and central nervous activity during general anesthesia. Fifteen ASA physical status I and II patients scheduled for TAH(Total Abdominal Hysterectomy). Patients were received to sadation with sevoflurane. The PSD(power spectrum density) of HRV(heart rate variability) and DFA(detrended fluctuation analysis) of EEG were used for the analysis. These values were measured at the preanesthetic period, intubation, operation, extubation and post-anesthesia with sedation. PSD and DFA of the ECG and EEG data were assessed to quantify the frequency band and the fractal and self-similarity properties of EEG signal. At intubation stage, high-frequency(HF) power (HF 0.15-0.4 Hz) and low-frequency(LF) power (LF 0.04 -0.15 Hz) both decreased compared with preanesthesia. But detrended fluctuation analysis(DFA) was increased compared with preanesthesia. At postanesthesia, HF, LF and DFA returned to preanesthesia. In this paper, we aimed to estimate the depth of anesthesia and review the correlation PSD of HRV and DFA of EEG during general anesthesia to estimate depth of anesthesia.