手术麻醉期间意识与中潜伏期听觉诱发电位的关系。

Relationship between awareness and middle latency auditory evoked responses during surgical anaesthesia.

作者信息

Aceto P, Valente A, Gorgoglione M, Adducci E, De Cosmo G

机构信息

Department of Anaesthesiology and Intensive Care, Catholic University of Sacred Heart, Rome, Italy.

出版信息

Br J Anaesth. 2003 May;90(5):630-5. doi: 10.1093/bja/aeg113.

DOI:10.1093/bja/aeg113

PMID:12697591

Abstract

BACKGROUND

Some studies support the view that meaningful auditory input can be processed by the brain during apparent surgical anaesthesia. Consequently, patients may be able to remember some information implicitly after anaesthesia as well through a 'dream-like process' (subconscious awareness). The aim of this study was to investigate the presence of subconscious awareness during anaesthesia and to examine its relationship to the mid-latency auditory evoked responses (MLAERs).

METHODS

We studied 40 patients, ASA I-II, undergoing laparoscopic cholecystectomy. General anaesthesia was induced with thiopental 5 mg kg(-1), fentanyl 3 micro g kg(-1), and vecuronium 0.08 mg kg(-1). For the maintenance of anaesthesia, patients were randomly assigned to one of four anaesthetic regimen groups: sevoflurane+air in oxygen 40%; sevoflurane+nitrous oxide 60%; isoflurane+air in oxygen 40%; and isoflurane+nitrous oxide 60%. MLAERs were recorded before anaesthesia, at 1 MAC of inhaled anaesthetic and then 30 min after awakening. An audiotape with one of four stories was played immediately after intraoperative MLAER recording. Explicit and implicit memory was assessed 24 h after awakening.

RESULTS

None of the patients had explicit recall. One of the patients from the isoflurane-air group showed implicit memory of listening to the audiotape. A dream-like process, in which they remembered implicitly the story played during anaesthesia, occurred in one of the patients from the sevoflurane-nitrous oxide group. In the patients with subconscious awareness, MLAERs were similar to that of the awake state with a Pa latency increase of less than 8.87. When there was a marked increase in Pa latency during anaesthesia, no subconscious awareness was observed. No statistically significant differences were found between Pa latency before and after anaesthesia.

CONCLUSIONS

MLAERs may help to predict subconscious cerebral processing of auditory inputs during anaesthesia.

摘要

背景

一些研究支持这样的观点，即在表面的手术麻醉期间大脑能够处理有意义的听觉输入。因此，患者在麻醉后也可能通过“梦境般的过程”（潜意识觉知）隐性地记住一些信息。本研究的目的是调查麻醉期间潜意识觉知的存在情况，并检验其与中潜伏期听觉诱发电位（MLAERs）的关系。

方法

我们研究了40例ASA I-II级接受腹腔镜胆囊切除术的患者。用硫喷妥钠5mg/kg(-1)、芬太尼3μg/kg(-1)和维库溴铵0.08mg/kg(-1)诱导全身麻醉。为维持麻醉，患者被随机分配到四个麻醉方案组之一：七氟醚+40%氧气中的空气；七氟醚+60%氧化亚氮；异氟醚+40%氧气中的空气；异氟醚+60%氧化亚氮。在麻醉前、吸入麻醉药1MAC时以及苏醒后30分钟记录MLAERs。术中MLAER记录后立即播放包含四个故事之一的录音带。苏醒后24小时评估显性和隐性记忆。

结果

所有患者均无显性回忆。异氟醚-空气组的一名患者表现出对听录音带的隐性记忆。七氟醚-氧化亚氮组的一名患者出现了梦境般的过程，即他们隐性地记住了麻醉期间播放的故事。在有潜意识觉知的患者中，MLAERs与清醒状态相似，Pa潜伏期增加小于8.87。当麻醉期间Pa潜伏期显著增加时，未观察到潜意识觉知。麻醉前后Pa潜伏期之间未发现统计学上的显著差异。