The Effects Of Fentanyl And Sufentanil On Bispectral Index Scale And Cerebral State Index

Objective: There is a debate regarding whether opioids, just as fentanyl and sufentanil, are adequately reflected in the assessment of sedation based on derivatives of the electroencephalogram. Bispectral Index (BIS) and cerebral state index (CSI) have been used to monitor the level of sedation based on the electroencephalogram (EEG). To compare the effects of sedation of fentanyl with equivalent analgesia dose sufentanil, we use a prospective, random ,comparative, single blinded method, monitor patients with bispectral index and cerebral state index, to observe whether fentainyl and sufentanil have effects on bispectral index of patients.Methods: 50 patients (ASAⅠ-Ⅱ, male 24 and female 26, height 155～175cm, weight 55～75kg, aged 65～75years), undergoing knee jiont replacement were chosen, randomly divided into 5 groups, with 10 patients in each group. Fentanyl low dose group (group FL) received fentanyl 2ug/kg while fentanyl high dose group (group FH) received 4ug/kg; sufentanil low dose group (SL group) received sufentanil 0.3ug/kg while sufentanil high dose group (group SH) received 4ug/kg; then the placebo group (group P) received sodium chloride solution 5ml. All patients had been injected into muscles with sodium luminal 200mg and atropine 0.5mg before operation. When the patient entered the operating-room we monitored them with BP, ECG, SPO2, BIS, CSI as usral. 20 minutes later BIS, CSI, MBP, BF and HR were recorded as the basical state and at the same time OAA/S was done within 30 seconds. Then fentanyl, sufentanil and placebo were infused randomly into diffrent patients depends on different groups. The way of infusion was intravenous injection and all drugs were diluted by sodium chloride solution in 5ml. We recorded BIS, CSI, MBP, BF, HR and OAA/S again 5 minutes later. We compare the records with those we had done before. If any patient appeared cramp, severe breath inhibition or anaphylaxis should be dropped out from the tests.Result: There were no significant differences among 5 groups with respect to age, weight and height ( P>0.05). the differences of BIS, CSI, MBP, BF, HR and OAA/S were not significant among 5 groups before the drugs were infused. There were significant differences between group FL and group P with respect to BF and OAA/S ( P<0.05), BF and OAA/S in group FL were lower than that in group P. But there were no significant differences with respect to BIS, CSI, MBP, HR between group FL and group P ( P>0.05). There were significant differences between group FH and group P with respect to BF, MBP, HR and OAA/S ( P<0.05). BF, MBP, HR and OAA/S in group FH decreased significantly than that in group P. Compare groug SL with group P, the results just like those in group FL with group P. There were significant differences between group SH and group P with respect to BF and OAA/S ( P<0.05), BF and OAA/S in group SH were lower than that in group P. But there were no significant differences with respect to BIS, CSI, MBP, HR between group SH and group P ( P>0.05). The differences in group FL with in group FH, BF,MBP,HR and OAA/S were significant( P<0.05). The differences in group SL with in group SH only BF and OAA/S were significant( P<0.05). so as to group FL and group SL, there were no significant differences between them( P>0.05), but to group FH and group SH, MBP,HR were different significantly, MBP and HR in group FH decreased more lower than that in group SH.Conclusions: 1 fentanyl and sufentanil have effects of sedation and with the dose raising the effects of sedation become stronger(OAA/S shows), but its effects of sedation can not be reflected in the assessment of sedation based on BIS and CSI. 2 under the equal dose of analgesia, fentanyl changes HR and MBP much more than sufentanil but there is no sigificant difference with respect to BIS and CSI between them.