麻醉是外科手术中必不可少的环节，临床中保障手术顺利进行的关键是判断并控制合适的麻醉深度，因此麻醉深度监测具有重要的临床实际意义。本项目拟针对麻醉深度监测不准确的问题，研究全身麻醉中更为深层次的脑神经机制，进而设计更合理的麻醉大脑状态监测方法。第一，在传感器空间和源空间上，利用高密度脑电从脑电微状态、功能连接和脑网络的角度去揭示全身麻醉的脑神经机制。第二，本项目提出了一种新的加权同步挤压小波双谱算法，并通过仿真研究和临床实验来验证该方法对脑电麻醉大脑状态监测准确性的提高。第三，本项目拟用线性和非线性方法来探索基于近红外光谱的麻醉大脑状态监测新方法，并依靠临床实验研究来证明其有效性及可靠性。预计该课题的研究成果能够为麻醉深度监测提供新的思路和理论基础。项目申请人已具有脑电和肌电信号处理及脑电源成像的研究经历，并已获得新算法的初步仿真研究结果和基于近红外光谱的麻醉大脑状态监测的初步临床研究结果。

Many surgical procedures would not be possible without the patient entering a state of general anesthesia. Inadequate GA may lead to intraoperative awareness with recall or to prolonged recovery and an increased risk of postoperative complications for the patient. Therefore, it is essential to monitor the depth of general anesthesia. In view of the inaccuracy of monitoring the depth of anesthesia, we will investigate the neural mechanisms of general anesthesia and further develop the reasonable methods of monitoring the brain status of anesthesia. Firstly, in sensor and source spaces, the neural mechanisms of general anesthesia were explored from the perspective of EEG microstate, functional connectivity and brain networks by using high-density EEG signals. Secondly, the weighted synchrosqueezing wavelet bispectral method was proposed to monitor the brain status of anesthesia by using EEG signals. The computer simulations and clinical experiments were employed to verify the improvement of accuracy of monitoring the brain status of anesthesia when using this proposed algorithm. Thirdly, linear and nonlinear approaches were used to develop the new methods of monitoring the brain status of anesthesia based on near-infrared spectroscopy. The clinical experiments were employed to prove the validity and reliability of new methods. It is expected that the research results of this project can provide new ideas and theoretical foundations for monitoring the depth of anesthesia. The principle investigator already had experiences about EEG and EMG signals processing and EEG source localization. Moreover, the PI has obtained some preliminary results about the computer simulations of new algorithm and the clinical investigations of monitoring the depth of anesthesia based on near-infrared spectroscopy.