Effects of different sevoflurane induction on hemodynamics in elders

Objective To compare the effects of sevoflurane incremental and high concentration rapid inhalation induction on hemodynamics in elders.Methods Forty aged over 65 years patients undergoing general anesthesia were equally randomized into incremental sevoflurane induction group(IS)and high concentration rapid sevoflurane induction group(RS).In IS group,patients were inspired sevoflurane from 2% to 5% via increasing 1% sevoflurane every 3 breaths.The initiation concentration of sevoflurane was 5% in RS group.The time of eyelash reflex loss,the time of BIS decreased to 60,and the incidence of cough/body move were also recorded.HR,SBP,DBP,MAP,SpO2,and BIS were measured before the induction(T1),at the beginning of inspiration(T2),1 min(T3),2 min(T4),5 min(T5)after inspiration,at the time of intubation(T6),and 1 min(T7),5 min(T8)after the intubation.Results There were 2 cases occurring cough or body move in RS group and 1 case in IS group.The time of eyelash reflex loss in RS group was significantly faster than in IS group [(64.2±33.7)s vs(138.0±82.7)s](P0.05).The time of BIS decreased to 60 in RS group was shorter than in IS group [189.1±28.7)s vs(232.2±36.8)s](P0.05).BIS decreased after 1 min sevoflurane inhalation in RS group and 5 min in IS group respectively.At the beginning of sevoflurane inspiration and after inspiration 1,2 min,BIS in RS group were significantly lower than in IS group(P0.05).Conclusion Sevoflurane inhalation induction has little effect on the hemodynamics in elders.The time of high concentration rapid sevoflurane inhalation induction is shorter than incremental sevoflurane inhalation induction.BIS decreased 1 min after sevoflurane inhalation in RS group.