Thornton C, Konieczko K, Jones J G, Jordan C, Doré C J, Heneghan C P
Division of Anaesthesia, Clinical Research Centre, Harrow, Middlesex.
Br J Anaesth. 1988 Mar;60(4):372-8. doi: 10.1093/bja/60.4.372.
Previous studies have shown a dose-related effect of a number of general anaesthetic agents on the early cortical waves in the auditory evoked response (AER). In this study the effect of surgical stimulation on these waves was examined in 11 patients anaesthetized with thiopentone, nitrous oxide and halothane and paralysed with pancuronium. The inspired nitrous oxide concentration and end-tidal halothane concentration were held constant at 70% and 0.3%, respectively, and baseline AER recordings were made. Following surgical stimulation there was a progressive and significant increase in the amplitude of waves Nb and Pb/Pc. Unambiguous autonomic responses were seen in three patients, but these were not significantly correlated with changes in the AER. We conclude from this, and previous studies, that the amplitude of cortical waves in the AER are sensitive not only to anaesthetic concentration but also to surgical stimulation. The AER may, therefore, provide a useful index of depth of anaesthesia, that is the balance between the effects of surgical stimulation and anaesthetic depression on central nervous system activity.
以往的研究表明，多种全身麻醉药对听觉诱发电位（AER）中的早期皮质波有剂量相关效应。在本研究中，对11例接受硫喷妥钠、氧化亚氮和氟烷麻醉并用泮库溴铵麻痹的患者，检查了手术刺激对这些波的影响。吸入氧化亚氮浓度和呼气末氟烷浓度分别保持在70%和0.3%不变，并进行AER基线记录。手术刺激后，Nb波和Pb/Pc波的振幅逐渐显著增加。在3例患者中观察到明确的自主反应，但这些反应与AER的变化无显著相关性。我们从本研究及以往研究得出结论，AER中皮质波的振幅不仅对麻醉浓度敏感，而且对手术刺激也敏感。因此，AER可能提供一个有用的麻醉深度指标，即手术刺激和麻醉抑制对中枢神经系统活动影响之间的平衡。
