The Comparison Of Bispectral Index And Cerebral State Index During The Remifentanil Anaesthesia With Propofol And Evalulation Of Memory

Objective: To investigate the effect of remifentanil with aniso-effective-site concentration propofol and comparison of bispectralindex(BIS) and cerebral state index(CSI), and evaluating explicit andimplicit memory during anaesthesia with propofol by target-controlledinfusion(TCI).Methods: 105 ASAâ… -â…¡patients of either sex, aged 18-50 yr,undergoing the selective operation with general anaesthesia (90patients)and local anaesthesia operation(15 patients) were randomlyassigned to one of seven groups of 15; group A₀, A=2.0μg.ml^-1(effective-site concentration of propofol by TCI); group B₀, B=4.0μg.ml^-1;group C₀, C=6.0μg.ml^-1 and control group=D (local anaesthesia operation).The patients of test group were induced with TCI ofpropofol at the target4.0μg.ml^-1. After the paitients slept, infused 2% Lidocaine 2ml throughthyrocricoid membrane into trachea, gived muscle relaxant VecuroniumBromide and intubated tracheal catheter. Then adjusted effective-siteconcentration to 2.0μg.ml^-1,4.0μg.ml^-1,6.0μg.ml^-1, lasting 20 minuteslater, inject 2μg.kg^-1 remifentanil and infuse 0.2μg.kg^-1.min^-1 continuouslywith micro pump in A,B,C groups. And in A₀, B₀, C₀ groups infusedwith normal sodium. The auditory stimulus was given 15 min later. Thepatients of control group D were given the auditory stimulus beforeoperation. The value of MAP,HR,BIS and CSI were recorded at timepoints T₀(before anaesthesia),T₁(after intubated 3min), T₂(beforeinfused),T₃(after infused 5min), T₄(after infused 10min),T₅(after infused15min and before auditory stimulus),T₆(after auditory stimulus). Six hours after the patients have recovered consciousness. The memoryfunction test were performed by another doctor.Results: In A,B,C groups, the MAP and HR of T₃ decreasedobviously, compared with that of T₂(before infused), the differences havestatistical significance (P＜0.05), then recovered gradually at 10minT₄(after infused 10min),T₅(after infused 15min), T₆(after auditorystimulus), there are no statistical significance compared with T₂ (P＞0.05),and the MAP and HR of T₃,T₄,T₅ and T₆ in A₀,B₀,C₀ groups have nostatistical significance compared with controlled groups (P＞0.05). In A,Bgroups, the value of BSI and CSI of every time points after remifentanilinfused decreased obviously, compared with that of T₂ and controlledgroups, the differences have statistical significance (P＜0.05), but in Cgroup the value of BSI don't decrease(P＞0.05), and the value of CSIdecreased yet(P＜0.05). The negative linear correlation were foundbetween BIS and CSI with effective-site concentration of propofol,r=-0.948,-0.951 respectively((P＜0.05, n=60).InA,A₀,B,B₀,C,C₀groups, there were no explicit memory, the muddy identified hearing rateof the patients of group A₀ was no significant difference compared to thecontrolled group D(P＞0.05), and that of group A,B,B₀,C,C₀ decreasedsignificantly compared to the control groupD(P＜0.01). The cutoff pointsof BIS and CSI for implicit memory were 46 and 45 respectively whenthe implicit memory disappeared at 4.0μg.ml^-1 level of effective-siteconcentration of propofol.Conclusion: (1)The value of BIS and CSI with effective-siteconcentration of propofol have negative linear correlation; (2)Remifentanil can strengthen the anaesthetic effect of propofol and reduceintra-operative awareness. BIS performed as well as CSI in terms ofpredicting depth of anaesthesia, but CSI is better than BIS in predicting deeper depth of anaesthesia at 6.0μg.ml^-1 level of effective-siteconcentration of propofol. (3) The implicit memory disappeared at4.0μg.ml^-1 level, the cutoff points of BIS and CSI for implicit memorywere 46 and 45 approximately.