Saravanan Balachandar, Kundra Pankaj, Mishra Sandeep Kumar, Surianarayanan Gopalakrishnan, Parida Pradipta Kumar
Department of Anaesthesiology and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
Department of Otorhinolaryngology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
Indian J Anaesth. 2018 Aug;62(8):592-598. doi: 10.4103/ija.IJA_245_18.
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.
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.
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; = 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; < 0.001).
Sevoflurane was associated with short-term olfactory identification impairment with a concomitant reduction in melatonin levels illustrating a possible humoral mechanism.
麻醉剂与术后认知功能障碍、味觉和嗅觉减退有关。我们旨在评估异氟烷、七氟烷、丙泊酚和区域麻醉对术后嗅觉阈值、嗅觉识别及联想记忆的内分泌调节的影响。
在这项观察者双盲随机对照研究中，164例美国麻醉医师协会身体状况分级为Ⅰ级和Ⅱ级且年龄大于50岁的患者被随机分为四组之一，分别接受区域麻醉、七氟烷全身麻醉、异氟烷全身麻醉和丙泊酚全静脉麻醉。在术前12小时（T0）、术后3小时（T1）以及出院时或术后第3天（T2）进行印地语精神状态检查、嗅觉阈值和嗅觉识别测试。此外，在T0和T1时测定血清褪黑素水平。用正丁醇测试嗅觉阈值，用宾夕法尼亚大学嗅觉识别测试（UPSIT）进行嗅觉识别。使用单因素方差分析、Kruskal-Wallis检验或Mann-Whitney检验分析数据。
与术前（T0）相比，接受七氟烷麻醉的患者在术后3小时（T1）时嗅觉识别得分较低（中位数19.5对22；P = 0.01）。与其他组相比，七氟烷组术后血浆褪黑素水平显著降低（17.34±4.8 pg/ml对23.2±3.5 pg/ml；P < 0.001）。
七氟烷与短期嗅觉识别障碍相关，同时褪黑素水平降低，这说明了一种可能的体液机制。
