Clinical study of appropriate concentrations of sevoflurane and propofol in elderly patients receiving laryngeal mask airway insertion

Objective To investigate the appropriate concentrations of sevoflurane inhalation and propofol target controlled infusion(TCI) in the elderly patients receiving laryngeal mask airway(LMA) insertion. Methods Sixty elderly surgical patients were randomly divided into the sevoflurane group(group S) and the propofol group(group P). According to the inhalation concentration of sevoflurane, group S was divided into group SA(5% sevoflurane) and group SB(7%sevoflurane); According to the effect compartment concentration of propofol TCI, group P was divided into group PA(target concentration of 2 μg/m L) and group PB(target concentration of 3 μg/m L). The changes of MAP, HR and Sp O2 and relevant complications before induction, immediately before LMA insertion, 1 minute after LMA insertion and 5minutes after LMA insertion were compared. Results Group PB was significantly lower than group PA in the blood pressure and heart rate(P0.05). After LMA insertion, the blood pressure and heart rates of group SA and SB increased,but the blood pressure and heart rate of group SB was significantly lower than those of group SA. Conclusion It is suggested that elderly patients receive laryngeal mask airway insertion under propofol TCI and the effect compartment concentration of propofol during laryngeal mask airway insertion be 2 μg/m L. When inserting laryngeal mask airway under sevoflurane inhalation induction, the appropriate inhalation concentration of sevoflurane is 8%.