The influence of dexmedetomidine on sedation and requirment of propofol during anesthesia induction / 临床麻醉学杂志

Objective To evaluate the influence of dexmedetomidine（Dex） on sedation and requirement of propofol during anesthesia induction. Methods Thirty patients（ASA Ⅰ or Ⅱ） undergoing selective operation were randomly divided into 2 groups：Dexmedetomidine group （group D,n=15） or control group （group C,n=15）. Patients in the group D received 1 μg/kg dex diluted to 10ml over 10 min by pumped infusion and patients in the group C was simply recieved normol saline at the same way.Twenty minutes after administrating the drug,patients in both groups were pumped propofol at the speed of 0.4 mg·kg-1·min-1. When holding up jaw without movement,patients received 1 μg/kg fentanyl and 0.6 mg/kg rocuronium,and endotracheal intubated 1.5 minutes later. RE,SE,Ramsay sedation scale of the patients were recorded before（T0） and after 5,10,20 minutes（T1-T3） of drug adminstration.The minimum dose and total dose of propofol during induction were recorded.Results Compared with group C and T0,RE and SE in group D decreased obviously at T1-T3 （P0.01）,while Ramsay sedation scale rised significantly （P0.01）. Compared with group C,the minimum dose and the total dose of propofol decreased obviously in group D during induction （P0.01）.Conclusion Dexmedetomidine causes sadetive without respiratory depression,and has the propofol sparing effect during anesthesia induction.

A comparison of state and response entropy versus the bispectral index values during cesarean section

BACKGROUND: This study was designed to compare the measured values between the measured EEG-entropy and BIS monitor values during general anesthesia for cesarean section. METHODS: Fourteen patients who were to undergo cesarean section were randomly selected for this study. After induction of anesthesia, desflurane was administered to achieve a steady-state end-tidal concentration of 3 vol%. The state entropy (SE), the response entropy (RE), the BIS and hemodynamic variables were collected at various time points. RESULTS: During the induction period, the SE, RE and BIS values were slightly different. However, these indices were not significantly different during the maintenance period. The SE and RE values correlated with the BIS value during general anesthesia for cesarean section. CONCLUSIONS: The changes in the SE and RE values followed a pattern that was similar to the BIS values during general anesthesia for cesarean section.

Effect of muscle relaxant on entropy during propofol anesthesia / 대한마취과학회지

BACKGROUND: The purpose of this study was to investigate whether muscle relaxant affect the values of Entropy, response entropy (RE) or state entropy (SE) during propofol anesthesia. METHODS: Eighty patients (ASA I) scheduled for elective surgery under general anesthesia were randomly assigned to four groups. Anesthesia was maintained at a SE value of 80 (80 +/- 2) using target controlled infusion (TCI) of propofol. After maintaining SE 80 for 5 min, vecuronium 0.1 mg/kg was injected intravenously in group I and same volume of normal saline was intravenously injected in group II. After maintaining SE 60 for 5 min, vecuronium 0.1 mg/kg was injected intravenously in group III and same volume of normal saline was injected intravenously in group IV. The mean arterial pressure, heart rate, SE and RE were measured before anesthetic induction and up to 5 min after vecuronium or normal saline injection in each group. RESULTS: SE and RE were not changed in group II, but significantly decreased in group I (P < 0.05, respectively). In group III and IV, SE and RE were not changed in both groups. There were no significant hemodynamic changes among the four groups. CONCLUSIONS: These results suggest that the effect of muscle relaxant on Entropy vary according to the baseline values of RE or SE during propofol anesthesia.