Effect Of Different Concentrations Of Sevoflurane Combined With Propofol Anesthesia On The Rocuronium-induced Neuromuscular Blockade

Objective To investigate the effect of different concentrations of sevoflurane combined with propofol anesthesia on the rocuronium-induced neuromuscular blockadeMethod Sixty-seven ASA I or II patients of both sexes, aged 20-65 years, height155-180 cm, weight 55-90 kg for elective abdominal operation were studied. All of the patients were randomly allocated to three groups according to random number table:propofol combined 0.5 Minimum alveolar concentration(MAC)end-tidal concentration of sevoflurane(group I, 24 cases), propofol combined 0.75 MAC end-tidal concentration of sevoflurane(group II, 20 cases),propofol combined 1MAC end-tidal concentration of sevoflurane(group III, 23 cases). All those patients were given midazolam 0.05mg/kg, sufentanil 0.3?g/kg, etomidate 0.3mg/kg for anesthesia induction. Rocuronium was given through the T1 mode of Closed-loop muscle relaxant infusion system and infused by 2ED95(0.6mg/kg). After tracheal intubation,different concentrations of sevoflurane inhalation combined with closed-loop intravenous propofol(Cp 0.5-5?g/ml) anesthesia, the propofol was given using target-controlled infusion(TCI). Intraoperative the BIS value was maintained at45-55. Sevoflurane was stopped inhalation about 30 min before operation finished,propofol and remifentanil were continue tagert-controlled infusion until end of operation.The following variables were recorded:averaged consumption dosage of rocuronium, recovery index(T1 recovery time from 25% to 75%), averaged consumption dosage of propofol and remifentanil.Statistical analysis The software SPSS 17.0 was used in analyzing measurement data, which was expressed as mean±standard deviation.One-Way ANOVA analysis was used to compare the mean of multiple groups.Tukey test was used for multiple comparisions between groups.Counting data was compared with Chi-Square test.P<0.05 was considered statistically significant.Results(1) The averaged consumption dosage of rocuronium in group I, II and III were 9.7±1.4ug·kg?1·min?1, 7.5±1.0ug·kg?1·min?1, 6.9±1.1ug· kg?1·min?1respectively.The consumption of rocuronim in group III was less as compared withgroup II and group I, the difference was statistically significant(P < 0.05).There were statistically significant difference between group I and group II(P < 0.05).(2) The recovery index in group I, II and III were 8.9±2.6, 8.9±2.5, 9.9±3.1 minutes respectively. There weren't difference among the three groups(P > 0.05).(3) The averaged consumption dosage of propofol in group I, II and III were 5.3±1.8,4.5±1.2, 2.2±0.7mg·kg?1·h?1. There was significant difference of propofol consumption between group I and III(P < 0.05), the same trend was found between group II and III(P < 0.05).There wasn't difference between group I and II(P > 0.05).(4) The averaged consumption dosage of remifentanil in group I, II and III were4.1±1.1, 3.9±0.8, 2.5±0.9ug·kg?1·h?1. There was significant difference of remifentanil consumption between group I and III(P < 0.05), the same trend was found between group II and III(P < 0.05).There wasn't difference between group I and II(P>0.05).Conclusion The averaged consumption dosage of rocuronium under 1MAC sevoflurane inhalation combined with propofol anesthesia was decreased 29%compared with 0.5MAC sevoflurane inhalation, and decreased 8% compared with0.75 MAC sevoflurane inhalation.The averaged consumption dosage of rocuronium under 0.75 MAC sevoflurane inhalation group was decreased 23% compared with0.5MAC sevoflurane inhalation.Under the sevoflurane combined with propofol anesthesia, the recovery index was no difference when the sevoflurane was stopped at about 30 min before the operation finished.