全麻诱导气管插管期间病人听觉诱发电位指数及心血管反应的变化

Changes in auditory evoked potential index during endotracheal intubation

目的观察听觉诱发电位指数(AAI)在全麻诱导气管插管过程中的变化及静脉注射利多卡因或地卡因喷喉对气管插管反应的影响。方法拟全麻诱导气管插管的择期病人36例,ASA分级及Mallampati插管分级均为Ⅰ或Ⅱ级,年龄19～55岁,随机分为3组(n=12),即对照组(C组)、利多卡因静脉组(L组)和地卡因喷喉组(T组),诱导药物和剂量相同,当AAI达10左右时,C组直接行气管插管,L组和T组患者分别在气管插管前给予1%利多卡因静脉注射和1%地卡因喷喉,记录气管插管前后1 min的AAI、血压、心率及开始插管距肌松药注入的时间。结果三组AAI值、血压及心率在全麻气管插管后1 min明显升高,T组AAI的升高幅度明显高于其他两组(P<0.05);L组的血压和心率升高幅度明显低于其他两组(P<0.05)。结论听觉诱发电位指数是反映气管插管反应的敏感指标,静脉注射利多卡因可减小气管插管的心血管反应。

Objective To investigate the changes in auditory evoked potential index (AEPI) during endotracheal intubation and the effects of intravenous lidocaine or topical anesthesia of larynx and vocal cords with tetracaine on intubation response. Methods Thirty-six patients classified as ASA physical status and Mallampati intubation status I or II , aged 19-55 yr scheduled for elective surgery under general anesthesia were randomly divided into 3 groups with 12 patients in each group: (1) control group (C) ; (2) intravenous lidocaine group (L) and (3) topical tetracaine group (T). The patients were premedicated with intramuscular atropine 0.01 mg·kg-1 and phenobarbital 0.1 g. Anesthesia was induced with midazolam 30 μg · kg-1, fentanyl 3 μg · kg-1 and propofol 1.5-2.0 mg·kg-1 . Direct vision tracheal intubation was performed at 3 min after vecuronium 0.1 mg·kg-1 . In group L 1 % lidocaine 1 mg · kg-1 was given i. v. after propofol injection. In group T the suproglottic area and vocal cords were sprayed with 1% tetracaine 3-5 ml before intubation. All intubations were performed by the same anesthesiologist. BP, HR, SpO2 and AAI value were recorded 1 min before and 1 min after intubation. The time between vecuronium injection and tracheal intubation was also recorded.Results AAI value, MAP and HR significantly increased after endotracheal intubation in all 3 groups. The increase in AAI value in group T was significantly larger than that in group C and L. The increase in MAP and HR in group L after intubation was significantly smaller in group L than in group C and T. There was no significant difference in MAP and HR between group C and T after intubation. Conclusion AAI is more sensitive than MAP and HR in terms of detecting the increase in AAI value induced by responses to tracheal intubation. Neither intravenous lidocaine nor tetracaine topical anesthesia of vocal cords inhibits the intubation. Intravenous lidocaine can attenuate the cardiovascular response to intubation.