Objective The aim of this study was to investigate if target-controlled-infusion of remifentanil as sole agent affect bispectal index(BIS) and auditory evoked potential index (AEPI).Methods Twenty two ASAⅠ-Ⅱpatients...Objective The aim of this study was to investigate if target-controlled-infusion of remifentanil as sole agent affect bispectal index(BIS) and auditory evoked potential index (AEPI).Methods Twenty two ASAⅠ-Ⅱpatients scheduled for elective surgery were enrolled in this study.A effect-site target-controlled infusion of remifentanil was started to increase concentration gradually , the initial remifentanil concentration was set at 2.0 ng·mL -1 and was increased by 1.0 ng·mL -1 until 8.0 ng·mL -1.At baseline and at each successive target concentration of remifentanil ,the BIS,AEPI ,observer’s assessment of alertness/sedation (OAA/S) ,hemodynamic variables and respiratory rate were recorded.Results Increasing predicted remifentanil effect-site concentration(CeREMI) decreased BIS value,compared with 0 ng·mL -1,the mean values of BIS were significantly reduced from 4.0 ng·mL -1(P<0.05).No significant difference in AEPI values were found.There was great variation existing in reaction to remifentanil in patients.BIS value decreased obviously in 9 patients(≤70)but in another 10 patients remained unchanged(≥90).In 9 remifentanil-sensitive patients,the spearman correlation coefficient of BIS mean value between CeREMI was -0.715 and between OAA/S was 0.705.However,in another10 remifentanil-insensitive patients,we had not found any correlation in BIS mean value between CeREMI or OAA/S. Conclusion We conclude that at the concentration used in clinical practice,great variation exists in patients’ reaction to remifentanil.Whether remifentanil affects BIS or not depend on if it produce sedative effect in patients.We have to consider the individual difference of BIS in remifentanil application.展开更多
文摘Objective The aim of this study was to investigate if target-controlled-infusion of remifentanil as sole agent affect bispectal index(BIS) and auditory evoked potential index (AEPI).Methods Twenty two ASAⅠ-Ⅱpatients scheduled for elective surgery were enrolled in this study.A effect-site target-controlled infusion of remifentanil was started to increase concentration gradually , the initial remifentanil concentration was set at 2.0 ng·mL -1 and was increased by 1.0 ng·mL -1 until 8.0 ng·mL -1.At baseline and at each successive target concentration of remifentanil ,the BIS,AEPI ,observer’s assessment of alertness/sedation (OAA/S) ,hemodynamic variables and respiratory rate were recorded.Results Increasing predicted remifentanil effect-site concentration(CeREMI) decreased BIS value,compared with 0 ng·mL -1,the mean values of BIS were significantly reduced from 4.0 ng·mL -1(P<0.05).No significant difference in AEPI values were found.There was great variation existing in reaction to remifentanil in patients.BIS value decreased obviously in 9 patients(≤70)but in another 10 patients remained unchanged(≥90).In 9 remifentanil-sensitive patients,the spearman correlation coefficient of BIS mean value between CeREMI was -0.715 and between OAA/S was 0.705.However,in another10 remifentanil-insensitive patients,we had not found any correlation in BIS mean value between CeREMI or OAA/S. Conclusion We conclude that at the concentration used in clinical practice,great variation exists in patients’ reaction to remifentanil.Whether remifentanil affects BIS or not depend on if it produce sedative effect in patients.We have to consider the individual difference of BIS in remifentanil application.