The Influence Of Different Target Controlled Propofol Delivery Systems On Plasma Concentration Of Cortisol And Prolactin During Induction Of Anesthesia

Objective: To study the influence of different target controlled propofol delivery systems on plasma concentration of cortisol and prolactin during induction of anesthesia. Methods: Thirty ASA Ⅰ— â…¡ patients (17male, 13 female), aged between 20-60yr, scheduled for surgery under general anesthesia were included in this study. Body weight ranged 45 —80kg. According to the ways of propofol given by different intravenous delivery system during induction of anesthesia, the patients were randomly divided into three groups of 10 each: (G₁) the Chinese pharmacokinetic model and parameters group and (G₂) the pharmacokinetic model and parameters by Tackley group as well as (G₃) BET group of which the TCI system was set up by manual infusion using Graseby 3500 infusion pump. 3 ug·ml^-1 target plasma concentration of propofol was obtained by three steps (10/8/6). As soon as the level of sedation was assessed by no response to prodding(OAA/S≤2) intubation was facilitated with fentanyl 2 ug·kg^-1 and vecuronium 0.1mg·kg^-1 intravenously. All patients were unpremedication. Radial artery was cannulated for blood sampling. MAP and HR were continuously monitored during induction of anesthesia. Blood samples were taken before induction of anesthesia (T₀baseline), after no response to prodding (T₁), immediately intubation(T₂), 3 minutes after intubation(T₃), 5minutes after intubation(T₄), 10 minutes after intubation(T₅) to measure plasma concentration of cortisol and prolactin. Meanwhile MAP and HR valueswere recorded at time of blood sampling. Results: During induction of anesthesia, the changes of HR and MAP over time have no significant difference among three groups(P > 0 .05). The changes of cortisol and prolactin over time have significant difference among three groups(P < 0 .01). At the endpoint of Ti, the concentration of prolactin was slightly increased. However the concentration of prolactin was decreased in three groups. The level of cortisol and prolactin were elevated at the time of intubation in three groups, which was less pronounced in the Gi and markedly in the G3. Conclusion: the three target controlled propofol delivery systems have been shown to blunts the hemodynamic and stress response to laryngoscopy. The G3 group was superior to the other two groups in controlling stress response. The plasma concentration of cortisol and prolactin would be better to predict the depth of sedation.