Total intravenous anesthesia with remifentanil-propofol given by target-controlled infusion in elderly patients

Objective To compare the effects of total intravenous anesthesia (TIVA) with remifentanil and propofol given by target-controlled infusion(TCI) between young and elderly patients.Methods Forty ASAⅠ-Ⅲpatients (24 male,16 female) undergoing elective orthopedic operation were studied after written informed consent.The patients were divided into 2 groups according to the age (n=20 each):groupⅠ＜65 yr and groupⅡ≥65 yr.After lactated Ringer's solution 5 ml·kg~(-1) was infused and preoxygenation (T_1) the target effect-site concentration of remifentanil was set at 1.0 ng·ml~(-1) and increased to 4.0 ng·ml~(-1)(T_2) in increments of 1.0 ng·ml~(-1).Then TCI of prepofol was started at target plasma concentration of 1μg·ml~(-1) which was increased to 4.0μg·ml~(-1)(T_3) in increments of 1.0μg·ml~(-1).After tracheal intubation (T_4) and before skin incision (T_5) the target plasma concentration of remifentanil and propofol were reduced to 3.0 ng·ml~(-1) and 3.0μg·ml~(-1) respectively. Anesthesia was maintained with remifentanil and propofol.MAP,HR,AAI,BIS,the incidence of adverse effects, the supplementary drugs used,emergence index,VAS score after extubation (T_6) and upon arrival in the ward were recorded.Results The decrease in BIS value was significantly larger at T_2 and T_3 in groupⅡthan in groupⅠ(P＜0.01).The MAP and HR were higher at T4 and Ts in groupⅠthan in groupⅡ.The incidence of bradycardia and the number of ephedrine and atropine administration were significantly higher in groupⅡthan in groupⅠ(P＜0.05).At loss of consciousness the target plasma concentration of propofol was (2.5±0.7)μg·ml~(-1) in groupⅠand (1.2±0.5)μg·ml~(-1) in groupⅡ.The effect-site concentration of remifentanil was (3.5±0.4) ng·ml~(-1) in groupⅠand (3.3±0.4) ng·ml~(-1) in groupⅡ.Conclusion Anesthesia with TCI of remifentanil-propofol can provide satisfactory depth of anesthesia for orthopedic operation.The incidence of adverse effects was low and emergence from anesthesia is quick.Attention should be paid to the changes in BP and HR.