Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, UK.
Center of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Br J Anaesth. 2020 Jul;125(1):67-76. doi: 10.1016/j.bja.2020.03.014. Epub 2020 Apr 24.
Subcortical structures, including the basal ganglia, have been proposed to be crucial for arousal, consciousness, and behavioural responsiveness. How the basal ganglia contribute to the loss and recovery of consciousness during anaesthesia has, however, not yet been well characterised.
Twelve patients with advanced Parkinson's disease, who were undergoing deep brain stimulation (DBS) electrode implantation in the subthalamic nucleus (STN), were included in this study. Local field potentials (LFPs) were recorded from the DBS electrodes and EEG was recorded from the scalp during induction of general anaesthesia (with propofol and sufentanil) and during tracheal intubation. Neural signatures of loss of consciousness and of the expected arousal during intubation were sought in the STN and EEG recordings.
Propofol-sufentanil anaesthesia resulted in power increases in delta, theta, and alpha frequencies, and broadband power decreases in higher frequencies in both STN and frontal cortical areas. This was accompanied by increased STN-frontal cortical coherence only in the alpha frequency band (119 [68]%; P=0.0049). We observed temporal activity changes in STN after tracheal intubation, including power increases in high-beta (22-40 Hz) frequency (98 [123]%; P=0.0064) and changes in the power-law exponent in the power spectra at lower frequencies (2-80 Hz), which were not observed in the frontal cortex. During anaesthesia, the dynamic changes in the high-gamma power in STN LFPs correlated with the power-law exponent in the power spectra at lower frequencies (2-80 Hz).
Apart from similar activity changes in both STN and cortex associated with anaesthesia-induced unresponsiveness, we observed specific neuronal activity changes in the STN in response to the anaesthesia and tracheal intubation. We also show that the power-law exponent in the power spectra in the STN was modulated by tracheal intubation in anaesthesia. Our results support the hypothesis that subcortical nuclei may play an important role in the loss and return of responsiveness.
皮质下结构，包括基底节，被认为对觉醒、意识和行为反应至关重要。然而，基底节在麻醉期间意识丧失和恢复中的作用尚未得到很好的描述。
本研究纳入了 12 例接受深部脑刺激（DBS）电极植入丘脑底核（STN）的晚期帕金森病患者。在全身麻醉（异丙酚和舒芬太尼）诱导和气管插管期间，从 DBS 电极记录局部场电位（LFP），从头皮记录脑电图（EEG）。在 STN 和 EEG 记录中寻找意识丧失和插管时预期觉醒的神经特征。
异丙酚-舒芬太尼麻醉导致 delta、theta 和 alpha 频率的功率增加，以及较高频率的宽带功率降低，在 STN 和额皮质区均如此。这伴随着 STN-额皮质相干性仅在 alpha 频带（119 [68]%；P=0.0049）增加。我们观察到气管插管后 STN 的时间活动变化，包括高 beta（22-40 Hz）频率的功率增加（98 [123]%；P=0.0064）和较低频率（2-80 Hz）功率谱中的幂律指数变化，而在额皮质区则没有观察到这些变化。在麻醉期间，STN 中的高 gamma 功率的动态变化与较低频率（2-80 Hz）的功率谱中的幂律指数相关。
除了与麻醉引起的无反应性相关的 STN 和皮质的类似活动变化外，我们还观察到 STN 对麻醉和气管插管的特定神经元活动变化。我们还表明，STN 中功率谱的幂律指数在麻醉期间受气管插管调节。我们的结果支持这样一种假设，即皮质下核可能在反应性的丧失和恢复中起重要作用。
