Results:
The Flow diagram is shown in Fig. 2 . Three patients refused to
intervention management after entering the operating room, four patients
were excluded for surgery method changed, and two were lost to
follow-up. Finally, enrolled 78 patients in the study: 25 patients in
high concentration group, 24 patients in middle concentration group, 28
patients in low concentration group.
No differences in age, BMI, HR and
MAP among the three groups (Table 1 ).
3.1 Primary endpoint
Concentration-change data for each patient received by the
up-and-down treatment were performed
in Fig. 3 (A, B, C). According to up-and-down method and probit
analysis, REM EC50 1.82 ng/mL (95% CI 0.94 to 2.27 ng/mL) in high
group, 2.96 ng/mL (95% CI 2.75 to 3.14 ng/mL0) in middle group, 5.14
ng/mL (95% CI 4.86 to 5.47 ng/mL) in low group (Fig. 3 D).
There was also no significant difference in MAP, HR, PSI and BIS related
to surgery among the three groups (Fig. 4 ), but compared with
middle and low group, the change of MAP and HR of high group were more
obvious at T4.
Operation duration, hospital day, VAS score in the first day after
sugery did not make imparity among three groups, however, the dose of
REM made statistical significance (P<0.05). Compared with
other two group,the incidence of adverse events, the extubation and
lengths of PACU stay in middle group was shortest (Table. 2 ). All
three groups denied intraoperative awareness and hyperpathia, no
postoperative delirium occurred.
3.2 Secondary endpoints
The analgesic response of REM can be obtained by DSA (Figure. 5 ),
EEG changes caused by different concentrations of REM were analyzed. It
can be seen that the slow delta wave (0.5-4HZ) and alpha wave (8-12HZ)
in a is more obvious than b in every part of the figure.
The area under the ROC curve (Fig. 6 ) for the PSI and BIS after
incision were 0.953 ± 0.02 and 0.888 ± 0.04, respectively, it was
confirmed that the two indexes could predict the consciousness state of
patients, and PSI was more sensitive than BIS.