The Clinical Study Of Narcotrend In Monitoring The Depth Of Sevoflurane Anesthesia

Objective Narcotrend is a new anesthetic depth monitor on the basis of EEG analysis, at present there is few clinic study on NCT for the anesthetic depth monitor of inhalation anesthesis. Therefore, the feasibility of NCT for the anesthetic depth monitor was studied during different concentrations of sevoflurane and the sevoflurane induced tracheal intubation.Method 75 ASA I - II patients, 20-49years old, undergoing gynecological operations with tracheal intubation were randomly divided into five groups(n=15) , according to different final concentration of sevoflurane. They are 0 MAC,0.6 MAC,0.8 MAC,1.0 MAC,1.3 MAC. After sevoflurane combined with rocuronium induced tracheal intubation, except group one, regulated other four groups patients' endexpiratory concentration of sevoflurane to the goal numbers, then kept for 15mins , recorded the numbers of NCT,BIS in all patients at this moment.30 patients in the same conditions were randomly divided into two groups(n=15), single drug group(sevoflurane) and combination group (sevoflurane and rocuronium). Patients in single drug group were induced with sevoflurane with the primary concentration of 8% till the final endexpiratory concentration reached to 2MAC for three minutes, then tracheal intubation was in progress, and continued to observe the indicators for three minutes. Patients in combination group gone through almost the same progress except the intravenous injection of rocuronium (2ED₉₀ 0.6mg/kg) after the loss of eyelash reflex. The NCT,BIS and hemodynamic were recorded during the whole process.Result In the first part, NCT and BIS in groups from 0.6MAC to 1.0MAC were lower than that in 0MAC group (P<0.05); increasing with the endexpiratory concentrations of sevoflurane, the NCT and BIS declined, but the declined extents were getting small. And NCT and BIS in 1.0MAC group were lower than in 0.8 MAC, but the difference was insignificant (P>0.05) ; the NCT in 0.6MAC,0.8MAC and 1.0MAC groups were higher than BIS in the same group (P<0.05 ) , but lower than BIS in 1.3MAC group (P<0.05) . The correlation coefficient between concentration of sevoflurane and NCT was 0.975 and determination coefficient was 0.950 (P<0.05 ) ; The correlation coefficient between concentration of sevoflurane and BIS was 0.972 and determination coefficient was 0.945 (P<0.05 ) .In the second part, there were no significant differences of NCT,BIS,MAP and HR between the two groups before tracheal intubation (P >0.05 ) . The NCT and BIS increased obviously than that before tracheal intubation (P<0.05), but were less than 60; there were no significant changes of NCT and BIS in combination group (P>0.05 ). The MAP and HR after tracheal intubation were higher than that before tracheal intubation (P<0.05), but the increasing extents in single drug group were bigger than that in combination group (P<0.05).Conclusions 1. NCT may be used as a good indicator for sevoflurane induced anesthetic depth monitoring; and NCT may be better than BIS as an anesthetic depth monitoring indicator in the high endexpiratory concentrations of sevoflurane induced anesthesia. 2. NCT may reflect the changes of anesthetic depth result from the nociceptive stimulus of tracheal intubation in sevoflurane induced anesthesia,; when combined with rocuronium, NCT can not reflect the changes of anesthetic depth result from the nociceptive stimulus of tracheal intubation.