Effects Of Different Target-controlled Concentrations Of Sufentanil On The MAC_BAR Of Sevoflurane In Patients With Carbon Dixoide Pneumoperitoneum Stimulus

Objective:To observe the effects of sufentanil infusion with different plasma target-controlled concentrations on the MAC_BARAR of sevoflurane?the minimum alveolar concentration that blocking the hemodynamic response?.Methods:125 patients,aged18-65 years,with American Society of Anesthesiologists physical status?-?,undergoing laparoscopic cholecystectomy,were enrolled in this study.All the patients were randomly divided into 5 groups?S₀,S₁.S₂,S₃,S₄?.with the different sufentanil plasma target concentrations?0.1,0.3,0.5,0.7ng/ml?.individually.All the patients were induced by propofol 2-4mg/kg,remifentanil 2ug/kg,.After the patient's consciousness disappeared,0.6mg/kg of rocuronium was injected to complete tracheal intubation.Then beginning to target infusion of sufentanil according to the given concentration.Sevoflurane was inhaled to maintain anesthesia according to its preseted end-tidal concentration.When the target control concentration of sevoflurane and the end-tidal sevoflurane concentration were maintained stable more than 20min,the pneumoperitoneum was began to established,the MAC_BARAR of sevoflurane was measured by using the up and down and sequential method.Simultaneously,the epinephrine and norepinephrine concentrations in the blood were also determined at corresponding time.Results:1.The MAC_BARAR of sevoflurane in group S₀,S₁,S₂,S₃ and S₄groupwere?5.33�0.13?%,?4.53�0.08?%,?2.86�0.15?%,?2.23�0.10?%,?2.13�0.08?%,which decreased by 15%?4.53%?,46%?2.86%?,60%?2.23%?and 61%?2.13%?when sufentanil was target controlled infusion with a plasma concentration of 0.1,0.3,0.5 or 0.7 ng/ml,respectively.But the decreased degree of sevoflurane MAC_BARAR was no significant difference between the two groups with 0.5 ng/ml and 0.7ng/ml of sufentanil plasma concentrations.2.No significant difference was found in concentration of epinephrine or norepinephrine among all the groups before pneumoperitoneum stimulation?p>0.05?.and also no significant difference was found after pneumoperitoneum stimulation?p>0.05?.In each grounp,There was no significant difference in the epinephrine or norepinephrine concentration between before and after pneumoperitoneum stimulation?p>0.05?.Conclusion:1,Increasing the plasma target sufentanil concentration can decrease the MAC_BARAR of sevoflurane.A capping effect of the decrease of sevoflurane's MAC_BARAR occurred when the sufentanil target control concentration was higher than 0.5ng/ml.2,When the depth of anesthesia could be inhibited the hemodynamics response to pneumoperitoneum stimulation in half patients,the changes of epinephrine or norepinephrine concentrations would be no significant difference during pneumoperitoneum stimulation no matter the target controlled sufentanil concentration how to change.