Comparison of neuromuscular blocking effects of different doses of cisatracurium in children

Objective To determine the neuromuscular effects of different doses of cisatracurium in children,so as to investigate the suitable anesthesia induction dose and its influence on cardiovascular system.Methods Fory-five male and female(American Society of Anesthesiologists class Ⅰ-Ⅱ) patients,aged 2-8 years,who were scheduled for elective surgery under general anesthesia,were randomly assigned to three groups according to the doses of cisatracurium: group Ⅰ(0.10 mg/kg),groupⅡ(0.15 mg/kg),and group Ⅲ(0.20 mg/kg).Anesthesia was induced with midazolam 0.2 mg/kg,fentanyl 2 μg/kg,and propofol 2-4 mg/kg,and maintained with N2O/ O2(50/50),2% sevoflure and continuous infusion of propofol.Neuromuscular block was assessed by monitoring the electromyographic response of the adductor pollicis to supramaximal train-of-four(TOF) stimulation.Onset time(time from cisatracurium administration to maximal depression of first twitch response ),duration of peak effect(time from cisatracurium administration to 5% recovery of T1),duration of clinical action(time from cisatracurium administration to 25% recovery of T1),duration of total action(time from cisatracurium administration to 95% recovery of T1) and recovery index(recovery of T1 from 25% to 75%) were recorded.The hemodynamic changes as well as symptoms such as erubescence and brochial spasm were also observed.Results There was no difference in the conditions of tracheal intubation among the three groups.There was no difference in the hemodynamic changes after the injection of cisatracurium between the three groups.The onset time periods in group Ⅱ and group Ⅲ were apparently shorter than that in group I,whereas there was no significant difference between group Ⅱ and group Ⅲ.The durations of peak effect,the durations of clinical action and durations of total action in three groups were significantly different.There was no difference in recovery index among the three groups.Conclusion Cisatracurium at 0.15 mg/kg is optimal when midazolam,fentanyl and propofol are used for induction of pediatric anaesthesia.(Shanghai Med J,2010,33: 156-158)