Influence of rocuronium on bispectral index during different effect-site concentration of propofol

Aim To investigate whether rocuronium can affect bispcetral index during different effect-site concentration of propofol.Methods Sixty ASA Ⅰ or Ⅱpatients undergoing elective surgery were enrolled in the study,based on Ce of propofol,the patients randomly divided into four groups(R2 and R3)and(C2 and C3)(n=15).When the Ce of propofol reached 4.0 mg·L-1 and OAA/S score was below one,a laryngeal mask airway was inserted,Ce was then maintained at 2.0 mg·L-1 or 3.0 for 20min.Rocuronium 2ED950.6 mg·kg-1 was given in groups R2 and R3,normal saline(5ml)was given in the other two groups.BIS values were recorded before induction of propofol immediately(T1),injection of rocuronium or normal saline immediately(T2),TOF reaching 0(T3),the first TOF twitch of muscle recovering to 5 %(T4).The need of time was also recorded when TOF returned to T3 and T4 in groups R2 and R3.Results There was no significant difference in sex,age,body weight among four groups.There was no significant difference in the effect of different effect-site concentration of propofol on muscle relaxation of rocuronium.There was no significant difference in BIS between groups C2 and C3 when T1-T4.The BIS of T3 and T4 were significantly lower than T2 in group R2 but not in group R3,C2 and C3.Compared with the same Ce,there was no significant difference between group R2,C2 and group R3,C3.Conclusion The different effect-site concentration of propofol had no obvious effect on muscle relaxation of rocuronium,but rocuronium altered the BIS scores in moderately sedated patients but not in deeply sedated patients.The scores of BIS were decreased after a bolus 2 times ED95 of rocuronium when Ce of propofol set at 2.0 mg·L-1,but when Ce of propofol set at 3.0 mg·L-1,there were no changes in BIS scores.