Effects of different doses of mivacurium chloride on muscle relaxation time- course and hemodynamics in children with different ages / 中国医师进修杂志

ABSTRACT

Objective To observe the effect of different doses of mivacurium chloride on muscle relaxation time-course and hemodynamics in children with different ages. Methods One hundred children of selective inguinal hernia repair under general anesthesia with endotracheal intubation from January 2016 to January 2017 were enrolled, and the age was 0.5 to 6.0 years. The children were divided into low age group (0.5 to 3.0 years) and high age group (3.1 to 6.0 years) according to the age, then the children were divided into low dose group (mivacurium chloride 0.20 mg/kg) and high dose group (mivacurium chloride 0.25 mg/kg) according to the doses of mivacurium chloride. Therefore, the children were divided into low age low dose group, low age high dose group, high age low dose group and high age high dose group with 25 cases each. The mean arterial pressure (MAP) and heart rates before anesthesia (T0) and 1 min (T1), 3 min (T2), 5 min (T3), 10 min (T4) after intravenous injection of mivacurium chloride were recorded. The times of first intravenous injection of mivacurium chloride to neuromuscular block 75% (ThD75), 90% (ThD90) and maximum (ThDmax) were recorded. The recovery index (RI) was recorded. The times of last intravenous injection of mivacurium chloride to onset of muscle convulsions (Th) and muscle convulsions recovery 10% (ThR10), 25% (ThR25), 75% (ThR75), 90% (ThR90) were recorded. The times of ratio of the fourth muscle twitch to the first muscle twitch (TOFR) recovery 75% (TOFR75) and 90% (TOFR90) were recorded. Results There were no statistical difference in MAP and heart rate among 4 groups (P＞0.05). The ThD75, ThD90 and ThDmax in low age low dose group were (126 ± 40), (163 ± 59) and (192 ± 49) s, those in low age high dose group were (73 ± 15), (115 ± 41) and (142 ± 37) s, those in high age low dose group were (149 ± 38), (193 ± 44) and (221 ± 47)s, and those in high age high dose group were (105 ± 32), (138 ± 35) and (167 ± 44)s. The ThD75, ThD90 and ThDmax in low age high dose group were significantly shorter than those in low age low dose group, those in high age high dose group were significantly shorter than those in high age low dose group, those in high age low dose group were significantly longer than those in low age low dose group, those in high age high dose group were significantly longer than those in low age high dose group, and there were statistical differences (P＜0.05). There were no statistical differences in Th, ThR10, ThR25, ThD75, ThD90, RI, TOFR75 and TOFR90 among low age low dose group and low age high dose group, high age low dose group and high age high dose group (P＞0.05). Conclusions In the children of 0.5 to 3.0 years, the effect of mivacurium chloride is significantly faster than that in the children of aged 3.1 to 6.0 years. Compared with 0.20 mg/kg of mivacurium chloride, 0.25 mg/kg of mivacurium chloride has less time to display muscle relaxation effect. The recovery time is not affected by age and induction dose. Mivacurium chloride has no significant effect on hemodynamics.