Lehmann K A, Krauskopf K H
Institut für Anaesthesiologie und operative Intensivmedizin, Universität zu Köln.
Anaesthesist. 1992 Jul;41(7):373-85.
Since the first case report by Winter-bottom [106], the problem of intraoperative awareness or recall has received increasing attention from patients, anaesthesiologists and, more recently, even law courts [4, 20, 21, 78]. Our own interest in awareness derives from a study with the opiate agonist tramadol as a supplement to balanced anaesthesia, which revealed an unexpectedly high incidence of about 65% of patients who could recall intraoperative music [55]. It was the aim of the present randomized double-blind study to evaluate, under identical experimental conditions, what the incidence would be with other analgesic supplements to balanced anaesthesia (fentanyl, pentazocine and ketamine). Because few reports on this subject are available in the German literature, it was felt that the result should be discussed within a comprehensive review. PATIENTS AND METHODS. A total of 60 patients (ASA I-II, age 27-66 years, weight 48-93 kg) undergoing elective gynaecological surgery of at least 90 min duration were each randomly assigned to one of three study groups (F, fentanyl; P, pentazocine; K, ketamine). Premedication was performed with diazepam 10 mg p.o. the evening before surgery and pethidine 1 mg/kg i.m.+promethazine 1.5 mg/kg i.m.+atropine 0.5 mg i.m. 60 min before anaesthesia. Induction was performed with alcuronium (2 + 8 mg), methohexital (1.5 mg/kg) and a bolus dose of the analgesic supplement (F, 5 micrograms/kg; P or K, 2 mg/kg), followed by continuous infusion (F, 2 micrograms kg-1 h-1, P or K 0.8 mg kg-1 h-1). Endotracheal intubation was performed with succinylcholine (1 mg/kg). Patients were ventilated to normocarbia using a Takaoka respirator (4 breaths/min, tidal volume 1600 ml, N2O/O2 75:25). If insufficient anaesthesia was suggested by increases in blood pressure or heart rate to more than 20% of preinduction values, excessive sweating or lacrimation, enflurane (0.5-2 vol.%) was added for short periods of time. At the end of surgery, patients were ventilated with 100% O2, and the neuromuscular block antagonized using atropine 0.5 mg and neostigmine 1 mg. Without prior announcement, tape-recorded music (Mantovani, 3 min followed by 3 min silence) was played to all patients via earphones throughout the time period between intubation and the end of nitrous oxide administration. Vegetative parameters, cumulative and relative enflurane application times and retrospective judgement of quality of anaesthesia by the anaesthesiologist were documented. Post-operative recovery and pain were monitored using verbal rating scales. Patients were interviewed immediately after extubation and on the day after surgery to determine the incidence of dreams and recollection of music. Patients were classified as amnestic if they could not recall the music, even with prompting, and partially amnestic if they remembered the music but were unable to define the time when they had heard it. No amnesia was assumed if patients recalled the intraoperative music spontaneously. Groups were statistically compared by means of analysis of variance, Mann-Wilcoxon rank sum test and chi-square test. RESULTS. Mean duration of anaesthesia was 129-134 min in the subgroups. The total analgesic supplement dose was F 614 +/- 129 micrograms, P 238 +/- 38 mg, and K 230 +/- 50 mg (mean +/- SD). Enflurane substitution was necessary in 45 patients, regardless of the type of analgesic supplement. Mean cumulative enflurane application time was 26-28% in the treatment groups, corresponding to about 20% of anaesthesia duration. The most important reasons for enflurane substitution were increases in blood pressure (mostly in groups F and P) or heart rate (K). Recovery was fastest with F, followed by P, and slowest with K. Retrospective judgement of the quality of anaesthesia by the anaesthesiologist did not differ significantly between the treatment groups. Most (93%) of the patients were satisfied with their anaesthesia; 2 patients each who received P and K were dis
自温特博特姆首次报告病例[106]以来，术中知晓或回忆问题越来越受到患者、麻醉医生的关注，最近甚至引起了法庭的关注[4,20,21,78]。我们对知晓问题的兴趣源于一项关于将阿片类激动剂曲马多作为平衡麻醉补充剂的研究，该研究发现约65%的患者能够回忆起术中音乐，这一比例出乎意料地高[55]。本随机双盲研究的目的是在相同的实验条件下，评估平衡麻醉使用其他镇痛补充剂（芬太尼、喷他佐辛和氯胺酮）时的发生率。由于德国文献中关于该主题的报道较少，因此认为应在全面综述中讨论研究结果。患者与方法。共有60例患者（ASA I-II级，年龄27 - 66岁，体重48 - 93 kg）接受至少90分钟的择期妇科手术，他们被随机分配到三个研究组之一（F组，芬太尼；P组，喷他佐辛；K组，氯胺酮）。术前用药为术前晚口服地西泮10 mg，麻醉前60分钟肌内注射哌替啶1 mg/kg + 异丙嗪1.5 mg/kg + 阿托品0.5 mg。诱导用药为阿库氯铵（2 + 8 mg）、美索比妥（1.5 mg/kg）和一剂镇痛补充剂（F组，5 μg/kg；P组或K组，2 mg/kg），随后持续输注（F组，2 μg·kg⁻¹·h⁻¹，P组或K组0.8 mg·kg⁻¹·h⁻¹）。用琥珀胆碱（1 mg/kg）进行气管插管。使用高冈呼吸机使患者通气至正常碳酸血症（4次/分钟，潮气量1600 ml，N₂O/O₂ 75:25）。如果血压或心率升高超过诱导前值的20%、出汗过多或流泪提示麻醉不足，则短时间添加恩氟烷（0.5 - 2体积%）。手术结束时，患者用100%氧气通气，并用阿托品0.5 mg和新斯的明1 mg拮抗神经肌肉阻滞。在未事先告知的情况下，在插管至氧化亚氮给药结束的整个时间段内，通过耳机向所有患者播放录制的音乐（曼托瓦尼，3分钟后沉默3分钟）。记录植物神经参数、恩氟烷累积和相对使用时间以及麻醉医生对麻醉质量的回顾性判断。使用视觉模拟评分法监测术后恢复和疼痛情况。拔管后立即和术后第一天对患者进行访谈，以确定梦境和音乐回忆的发生率。如果患者即使在提示下也无法回忆起音乐，则分类为遗忘；如果患者记得音乐但无法确定听到音乐的时间，则分类为部分遗忘。如果患者自发回忆起术中音乐，则认为没有遗忘。通过方差分析、曼 - 惠特尼秩和检验和卡方检验对各组进行统计学比较。结果。各亚组的平均麻醉持续时间为129 - 134分钟。总镇痛补充剂剂量分别为：F组614 ± 129 μg，P组238 ± 38 mg，K组230 ± 50 mg（平均值 ± 标准差）。无论镇痛补充剂类型如何，45例患者需要恩氟烷替代。治疗组恩氟烷平均累积使用时间为26 - 28%，约占麻醉持续时间的20%。恩氟烷替代的最重要原因是血压升高（主要在F组和P组）或心率升高（K组）。F组恢复最快，其次是P组，K组最慢。麻醉医生对麻醉质量的回顾性判断在治疗组之间无显著差异。大多数（93%）患者对麻醉满意；接受P组和K组治疗的患者各有2例不满意。
