听觉诱发电位指数指导全凭静脉麻醉期间病人输注异丙酚的效果

Auditory evoked potential index for monitoring depth of anesthesia during propofol-remifentanil anesthesia

目的探讨听觉诱发电位指数(AAI)指导全凭静脉麻醉期间病人输注异丙酚的效果。方法择期全麻下行腹腔镜胆囊切除术病人60例,ASAⅠ或Ⅱ级,随机分为2组(n=30):试验组(Ⅰ组)和对照组(Ⅱ组)。静脉诱导气管插管后,持续输注0．2μg·kg-1·min-1瑞芬太尼以维持合适的麻醉深度。Ⅰ组通过监测AAI调节异丙酚输注速率,使AAI维持在30以下,Ⅱ组根据病人血压及心率调节异丙酚输注速率,每5分钟增减0．01 mg·kg-1·min-1异丙酚。记录气腹前(T1)、气腹后(T2)、分离胆囊(T3)、腹腔冲洗(T4)、手术结束(T5)时2组的血压、心率、AAI和输注异丙酚的速率,同时记录2组异丙酚、维库溴铵、瑞芬太尼用量、术毕睁眼时间、应答时间和拔管时间。结果2组各时间点AAI差异有统计学意义(P<0．05),与Ⅱ组相比,Ⅰ组输注异丙酚速率以及总用量减少(P<0．05)。术后24 h随访病人均无术中知晓。结论AAI指导全凭静脉麻醉输注异丙酚用于腹腔镜胆囊切除术病人,可较好的控制麻醉深度,指导合理用药,避免病人术中知晓。

Objective To investigate the feasibility of using auditory evoked potential index （AAI） to titrate the rate of propofol infusion during TIVA with propofol and remifentanil. Methods Sixty ASA Ⅰ or Ⅱ patients of both sexes scheduled for elective laparascopic cholecystectomy under general anesthesia were randomly divided into 2 groups （ n = 30 each） ： Ⅰ AAI group and Ⅱ control group. Noninvasive BP, HR, ECG, SpO2 and PET CO2 were monitored during anesthesia. Anesthesia was induced with midazolam 0.02 mg· kg^-1 , fentanyl 3-4 μg· kg^-1 and propofol 1-2 mg· kg^-1 . Tracheal intubation was facilitated with vecuronium 0.1 mg· kg^- 1. The patients were mechanically ventilated. PET CO2 was maintained at 35-40 mm Hg. Anesthesia was maintained with infusion of propofol and remifentanil and intermittent IV boluses of vecuronium. Remifentanil was infused at a constant rate of 0.2 μg·kg^-1·min^-1 . Propofol infusion rate was adjusted by AAI （Denmeter A/S Co, Denmark） in group Ⅰ . AAI value was maintained below 30. In control group propofol infusion rate was adjusted according to the change in BP and HR （ ± 15% of the baseline value before anesthesia）. The propofol infusion rate was adjusted by 0.01 mg· kg^-1. min^-1 every 5 min. The BP, HR, AAI value, propofol infusion rate were recorded before pneumoperitoneum （T1） ; after pneumoperitoneum （T2） ; the gall bladder was being isolated （T3） ; the peritoneum was being flushed （T4） and at the end of surgery （T5）. The amount of propofol, vecuronium, and remifentanil consumed, the time from the end of operation to eye-opening on command, the time from the end of operation to orientation and extubation were also recorded. Results The two groups were comparable with respect to demographic data, duration of anesthesia and the amount of remifentanil consumed. There was no significant difference in the time from end of operation to eye-opening on command, to orientation and extubation between the two groups. The propofol infusion rate was significantly slower and the total amount of propofol infused was significantly less in AAI group than in control group. No patient claimed to have awareness during operation. Conclusion Monitoring the depth of anesthesia with AAI during TIVA with propofol-remifentanil can maintain adequate and smooth anesthesia with less anesthetic and avoid intraoperative awareness.