Abstract: ［Abstract］ Objective〖HTSS〗〓To investigate application of different doses of mivacurium for bronchial foreign body removal in children with different ages.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓One hundred  children undergoing removing bronchial foreign body were enrolled. All the children were randomly divided into four groups according to their age and the initial dosage of mivacurium（n=25）. Ⅰa and Ⅰb group(child group,1-3 years old): respectively intravenous injection of mivacurium 0.15 mg/kg and 0.20 mg/kg when induction of anesthesia; Ⅱa and Ⅱb group(older child group,3-5 years old): respectively intravenous injection of mivacurium 0.15 mg/kg and 0.20 mg/kg when induction of anesthesia. The muscle relaxation time index was observed and recorded which including the onset time, clinical duration, RI,TOFr75 and TOFr 90. MAP, HR and blood oxygen saturation were observed and recorded at the time of preinserting the bronchoscopy and after inserting the bronchoscopy. The mirror satisfaction rates, the operation time and occurrence of adverse reactions also were recorded.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓Compared with Ⅰa , Ⅱa group, there were significantly shortened inⅠb and Ⅱb group in ThDmax, ThD75 and ThD90(P＜005). Comparison with groupⅠa, Ⅰb, the ThDmax was obviously prolonged inⅡa and Ⅱb group(P＜005).There were no difference in the time of clinical action, RI, TOFr75 and TOFr90(P＞005). The satisfaction rates of the four groups were 96.0%, 100.0%, 88.0% and 96.0% in inserting mirror, respectively. There was no significant difference in the four groups(P＞005). There were no significant difference in MAP, HR and blood oxygen saturation before and after bronchoscope after injection of mivacurium chloride(P＞005). The incidence rate of skin flushing was no significant difference(P＞005). Low blood pressure and bronchospasm were not observed in the four groups.
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓It was found that the onset time for children was obviously shorter than that for the elder ones when the same doses of mivacurium were used during the anesthesia induction. While, there were not differences between the two groups of children on the muscle relaxation effect. 0.15 mg/kg mivacurium can offer a satisfactory muscular relaxant effect for the children undergoing removing bronchial foreign body.

Key words: trachea, foreign bodies, mivacurium, child