麻醉药对嗅觉阈值和嗅觉识别能力的影响
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Nighttime Extubation Does Not Increase Risk of Reintubation, Length of Stay, or Mortality: Experience of a Large, Urban, Teaching Hospital.
背景与目的
麻醉药可引起患者术后认识、味觉和嗅觉功能障碍。我们旨在探讨异氟醚、七氟醚、丙泊酚和区域阻滞麻醉对患者术后嗅觉阈值、嗅觉识别和受激素调节的联想记忆的影响。
方 法
共纳入164名患者，年龄＞50岁，ASA分级I-ll，采用随机单盲法分为四组：异氟醚组、七氟醚组、丙泊酚组和区域阻滞组。于术前12h(T0)、术后3h(T1)、离院时或术后第3天（T2)时点进行心理、嗅觉阈值和嗅觉识别测试；于T0和T1时点进行血浆褪黑素水平的检测。采用宾夕法尼亚大学气味辨别试验（UPSIT)，正-丁醇和嗅觉辨别进行嗅觉阈值的测试。实验数据采用单因素方差分析， Kruskal-Wallis 或 Mann-whitney检验。
结 果
与T0时点比较，七氟醚组患者在T1时点（术后3h)嗅觉识别评分显著降低（中位数为19.5 vs 22,P=0.01）。与其他三组比较，七氟醚组血浆褪黑素水平显著降低（17.34 ± 4.8 pg/ml vs 23.2 ± 3.5 pg/ml; P<0.001）。
结 论
七氟醚引起短期嗅觉识别障碍，伴随血浆褪黑素水平降低，可能与体液机制有关。
原始文献摘要
Saravanan B,Kundra P, Mishra SK,et al.Effect of anaesthetic agents on olfactory threshold and identification – A single blinded randomised controlled study[J].Indian J Anaesth
Backgrand: Anaesthetics are implicated in cognitive dysfunction, taste and odour deficits in the postoperative period. We aimed to assess the effect of isoflurane, sevoflurane, propofol and regional anaesthesia on the olfactory threshold, olfactory identification and endocrine regulation of associative memory in the postoperative period.
Metheds: In this observer-blinded randomised controlled study, 164 patients (>50 years) with the American Society of Anesthesiologists I and II status were randomised into one of four groups to receive regional anaesthesia, general anaesthesia with sevoflurane, general anaesthesia with isoflurane and total intravenous anaesthesia with propofol. Hindi Mental State Examination, olfactory threshold and olfactory identification were tested at 12 h preoperatively (T0), at 3 h postoperatively (T1) and at the time of discharge or postoperative day 3 (T2). In addition, serum melatonin levels were estimated at T0 and T1. The olfactory threshold was tested with n-butyl alcohol and olfactory identification with the University of Pennsylvania Smell Identification Test (UPSIT). Data were analysed using the one-way analysis of variance, Kruskal-Wallis or Mann-whitney tests.
Results：The olfactory identification scores were lower with patients receiving sevoflurane-based anaesthesia at 3 h postoperatively (T1) when compared to preoperative (T0) (median 19.5 vs. 22; P = 0.01). This was accompanied by a significant postoperative reduction of plasma melatonin levels in sevoflurane group when compared to other groups (17.34 ± 4.8 pg/ml vs 23.2 ± 3.5 pg/ml; P < 0.001).
Conclusion: Sevoflurane was associated with short-term olfactory identification impairment with a concomitant reduction in melatonin levels illustrating a possible humoral mechanism.
麻醉学文献进展分享
贵州医科大学高鸿教授课题组
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