Madler C, Keller I, Schwender D, Pöppel E
Institute of Anaesthesiology, University of Munich, Germany.
Br J Anaesth. 1991 Jan;66(1):81-7. doi: 10.1093/bja/66.1.81.
There is evidence from neuropsychological and psychophysical measurements that sensory information is processed in discrete time segments. The segmentation process may be described as neuronal oscillation at a frequency of 30-40 Hz. Stimulus-induced neuronal oscillations of this frequency are found in the middle latency range of the auditory evoked potential (AEP). We have studied the effect of different end-tidal concentrations of isoflurane on auditory evoked 30-40 Hz neuronal oscillations. We studied 13 patients undergoing intra-abdominal urological and gynaecological procedures. AEP were recorded in the awake state and during end-expiratory steady state isoflurane concentrations of 0.3, 0.6 and 1.2 vol%. These incremental doses of isoflurane caused a stepwise decrease in frequency of oscillations. The decrease in oscillation frequency and sometimes the disappearance of oscillatory components may be interpreted as suppression of sensory information processing. The measurement of auditory evoked neuronal oscillations in the AEP appears to be a promising tool to monitor both sensory information processing capacity and depth of anaesthesia.
神经心理学和心理物理学测量的证据表明，感觉信息是在离散的时间段内进行处理的。这种分割过程可以描述为频率为30 - 40赫兹的神经元振荡。在听觉诱发电位（AEP）的中潜伏期范围内发现了这种频率的刺激诱发神经元振荡。我们研究了不同呼气末异氟烷浓度对听觉诱发的30 - 40赫兹神经元振荡的影响。我们研究了13例接受腹部泌尿外科和妇科手术的患者。在清醒状态以及呼气末异氟烷浓度分别为0.3、0.6和1.2体积%的稳态期间记录AEP。这些递增剂量的异氟烷导致振荡频率逐步降低。振荡频率的降低以及有时振荡成分的消失可以解释为感觉信息处理受到抑制。测量AEP中的听觉诱发神经元振荡似乎是监测感觉信息处理能力和麻醉深度的一种有前景的工具。
