年龄因素对全麻诱导时羟考酮抑制患儿气管插管反应量效关系的影响

Influence of age factors on dose-effect relationship of oxycodone inhibiting responses to tracheal intubation during induction of general anesthesia in pediatric patients

目的评价年龄因素对全麻诱导时羟考酮抑制患儿气管插管反应量效关系的影响。方法选取拟在气管插管全身麻醉下行择期手术的患儿,性别不限,年龄6个月至6岁,ASA分级Ⅰ或Ⅱ级,BMI 12~22 kg/m^(2),根据年龄将患儿分为3组:婴儿组(I组,6~12个月)、幼儿组(Y组,>1~3岁)和学龄前儿童组(P组,>3~6岁)。所有患儿缓慢静脉注射羟考酮,2 min后静脉注射依托咪酯0.3 mg/kg及顺式阿曲库铵0.15 mg/kg,3 min后可视喉镜下行气管插管术。记录气管插管前即刻的MAP、HR和气管插管后3 min内MAP、HR的峰值。采用改良Dixon序贯法,每组羟考酮初始剂量为0.3 mg/kg,若气管插管反应阳性,则下一例患儿羟考酮剂量增加0.02 mg/kg;若气管插管反应阴性,则下一例患儿羟考酮剂量降低0.02 mg/kg。气管插管反应阳性标准:气管插管后3 min内MAP和/或HR升高且峰值升高幅度超过气管插管前水平的20%。重复以上过程,直至出现7个阴性和阳性反应交叉后停止试验。采用Probit法计算羟考酮的半数有效剂量(ED_(50))及其95%置信区间(95%CI)。结果I组、Y组、P组患儿全麻诱导时羟考酮抑制气管插管反应的ED_(50)(95%CI)分别为0.280(0.247~0.301)、0.321(0.304~0.342)、0.354(0.342~0.368)mg/kg,随着年龄的增长,患儿全麻诱导时羟考酮抑制气管插管反应的ED50逐渐升高(P<0.05)。结论对于6个月至6岁的患儿,随着年龄的增长,全麻诱导时羟考酮抑制气管插管反应的效力逐渐降低。

Objective To evaluate the influence of age factors on dose-effect relationship of oxycodone inhibiting responses to tracheal intubation during induction of general anesthesia in pediatric patients.Methods American Society of Anesthesiologists Physical Status classificationⅠorⅡpediatric patients of both sexes,aged 6 months-6 yr,with body mass index of 12-22 kg/m^(2),scheduled for elective surgery under general anesthesia with tracheal intubation,were divided into 3 groups:infant group(group I,6-12 months),young children group(group Y,>1-3 yr)and preschooler group(group P,>3-6 yr).Oxycodone was slowly injected intravenously,2 min later etomidate 0.3 mg/kg and cisatracurium 0.15 mg/kg were intravenously injected,and 3 min later endotracheal intubation was carried out with a visual laryngoscope in all the children.Mean arterial pressure(MAP)and heart rate(HR)immediately before intubation and peak MAP and HR within 3 min after intubation were recorded.The modified Dixon′s sequential method was used.The initial dose of oxycodone was 0.3 mg/kg in each group.If the response to tracheal intubation was positive,the dose of oxycodone was increased by 0.02 mg/kg in the next child;if the response to tracheal intubation was negative,the dose of oxycodone was decreased by 0.02 mg/kg in the next child.Positive response to tracheal intubation was defined as increase in MAP and/or HR and increase in the peak value exceeding 20%of the pre-intubation level within 3 min after tracheal intubation.The aforementioned process was repeated until 7 negative and positive reactions crossed,and then the test was stopped.The median effective dose(ED_(50))and 95%confidence interval of oxycodone were calculated by Probit method.Results The ED_(50)(95%confidence interval)of oxycodone inhibiting responses to the tracheal intubation were 0.280(0.247-0.301)mg/kg,0.321(0.304-0.342)mg/kg and 0.354(0.342-0.368)mg/kg in I,Y and P groups,respectively.The ED50 of oxycodone inhibiting responses to the tracheal intubation was gradually increased during induction of general anesthesia with increasing age(P<0.05).Conclusions For children aged 6 months to 6 yr,the potency of oxycodone in inhibiting responses to the tracheal intubation during general anesthesia induction gradually decreases with increasing age.