BIS指导下丙泊酚闭环靶控输注在老年患者开腹手术中的应用

Application of closed-loop target-controlled infusion of propofol guided by bispectral index in the elderly undergoing laparotomy

目的探讨BIS指导下丙泊酚闭环靶控输注在老年患者开腹手术中的应用效果。方法择期全麻下行开腹手术的老年患者60例,男38例,女22例,年龄65~80岁,ASAⅠ~Ⅲ级,随机分为两组：闭环组（A组）和开环组（B组）,每组30例。两组采用相同的诱导方式。BIS下降至60且连续15s小于或等于60时A组丙泊酚以BIS值45~55为目标自动闭环反馈输注,B组手动调节丙泊酚维持BIS在45~55之间。两组均用肌松监测反馈仪闭环输注顺阿曲库铵,手动调节瑞芬太尼。记录入室后5min（T0）、插管即刻（Tl）、插管后3min（T2）、切皮后3min（T3）、腹腔探查时（T4）、缝皮结束时（T5）的BIS值、MAP、HR,记录两组麻醉时间、拔管时间及丙泊酚、瑞芬太尼、顺阿曲库铵、阿托品、麻黄碱、乌拉地尔和硝酸甘油等使用量,统计闭环系统性能指标：总体分数（GS）,充分麻醉（40〈BIS〈60）所占时间比例。用MMSE表对两组患者术前1d、术后第3天和第5天的认知功能进行评分。结果两组患者各时点HR差异无统计学意义。T4时A组MAP、BIS明显高于B组（P〈0.05）。A组丙泊酚用量和靶控浓度明显低于B组（P〈0.05）,两组患者瑞芬太尼、顺阿曲库铵使用量,麻黄碱、阿托品、乌拉地尔、硝酸甘油的使用例数差异无统计学意义。A组术后拔管时间[（27±8）min]明显短于B组[（36±10）min]（P〈0.05）,A组GS[（28±10）分]明显低于B组[（49±11）分]（P〈0.05）,充分麻醉（40〈BIS〈60）所占时间比例A组（82%±9%）明显高于B组（67%±9%）（P〈0.05）。术后第5天MMSE,A组[（28.57±0.87）分]明显高于B组[（26.83±0.91）分]（P〈0.05）,但术后认知功能障碍的发生率差异无统计学意义。结论 BIS指导下丙泊酚闭环靶控输注用于开腹手术的老年患者,麻醉效果良好,但在腹腔探查时患者血压有波动;BIS指导下丙泊酚闭环靶控输注可很好地维持BIS在设定的范围内;可减少全身麻醉药物的使用,缩短拔管时间,减轻对术后早期认知功能的影响。

Objective To investigate the application of closed-loop target-controlled infusion（TCI）of propofol guided by BIS in the elderly undergoing laparotomy.Methods Sixty elderly patients（male 38 cases,female 22 cases,aged 65-80 years,ASA Ⅰ-Ⅲ grades）scheduled for laparotomy under general anesthesia were divided into 2groups randomly：closed-loop group（group A）and open-loop group（group B）,30 cases in each.Anesthesia induction was same in the two groups.In group A,if BIS went down to 60 and kept less than or equal to 60 for 15seconds,propofol was infused as feedback automaticly to achieve the target BIS value of 45-55.Otherwise,the BIS of group B was kept at 45-55 manually.Muscle relaxation monitors were used to conduct closed-loop infusion of cisatracurium.Remifentanil infusion rate was adjusted manually in both groups.Recorded BIS,mean arterial pressures（MAP）and heart rates（HR）on time points of 5min after inter-room（T0）,intubation（Tl）,3minutes after intubation（T2）,3minutes after skin incision（T3）,abdominal exploration（T4）and the end of the skin suture（T5）.The anesthesia duration,extubation time were recorded too.Dosage of propofol remifentanil,cisatracurium,atropine,ephedrine,urapidil and nitroglycerin were also recorded.The closed-loop system performance indexs,including global score（GS）and the percentage of adequate anesthesia time（defined as BIS between 40 and 60）were calculated.The cognitive function of the patients was evaluated by the Mini-Mental State Examination（MMSE）one day before the operation and 3,5days after the operation respectively.Results There was no significant difference in heart rate（HR）between the two groups on all time points.There was significant difference in mean arterial pressure（MAP）and BIS on T4.MAP and BIS of group A were higher than group B respectively.（P〈0.05）;The average dosage and target controlled concentration of propofol in group A were lower than those of group B（P〈0.05）.There were no significant differences in dosage of remifentanil,cisatracurium,atropine,ephedrine,urapidil and nitroglycerin between the two groups;Compared with group B,the postoperative extubation time of group A was shorter（group A27±8min vs group B 36±10min,P〈0.05）,and the global score and the percentage of adequate anesthesia time（40〈BIS〈60）of group A were better（group A 28±10vs group B 49±11,P〈0.05;group A 82%±9%vs group B 67%±9%,P〈0.05）;the MMSE score of group A 5days after surgery was higher than group B（group A 28.57±0.87 vs group B 26.83±0.91,P〈0.05）.There was no significant difference in incidence of postoperative cognitive dysfunction between the two groups.Conclusion Closed loop TCI of propofol guided by BIS in the elderly undergoing laparotomy achieved favourable effect,but blood pressure fluctuated when detecting the abdominalcavity Closed loop of propofol TCI can maintain BIS in a speficied variation.and reduce dosage of anesthetics.It also could shorten extubation time and reduce the impact on early postoperative cognitive function.