年龄因素对右美托咪定镇静效应的影响

Effects of age factors on sedation induced by dexmedetomidine

目的 评价年龄因素对右美托咪定镇静效应的影响.方法 择期拟行下肢或下腹部手术患者139例,年龄18～103岁,体重指数≤30 kg/m2,根据年龄分为4组：Ⅰ组（18岁≤年龄≤44岁,n=40）、Ⅱ组（45岁≤年龄≤59岁,n=38）、Ⅲ组（60岁≤年龄≤89岁,n=39）和Ⅳ组（≥90岁,n=22）.蛛网膜下腔注药后20 min,经10 min静脉输注1μg/kg右美托咪定.记录右美托咪定的起效时间和镇静持续时间,记录低氧血症、心动过缓及低血压等不良反应的发生情况.结果 4组镇静起效时间和心动过缓发生率差异无统计学意义（P＞0.05）.与Ⅰ组比较,Ⅱ-Ⅳ组镇静持续时间延长（P＜0.05）;与Ⅱ组和Ⅲ组比较,Ⅳ组镇静持续时间延长（P＜0.05）.Ⅳ组低氧血症和低血压的发生率较Ⅰ-Ⅲ组升高（P＜0.05）.结论 右美托咪定的镇静效应受年龄因素影响,特别是对于≥90岁的患者右美托咪定的镇静时间延长,不良反应发生增多.

Objective To evaluate the effects of age factors on sedation induced by dexmedetomidine.Methods One hundred and thirty-nine patients,aged 18-103 yr,with body mass index ≤ 30 kg/m2,scheduled for elective surgeries on lower abdomen or lower extremities,were divided into4 groups according to the age：group Ⅰ （18 yr≤age≤44 yr,n=40）;group Ⅱ （45 yr≤age≤59 yr,n=38）;group Ⅲ （60 yr≤age≤89 yr,n=39）;group Ⅳ （≥90 yr,n=22）.A catheter was placed in the subarachnoid space at L3,4 interspace,and ropivacaine 10-20 mg was injected via the catheter.At 20 min after ropivacaine injection,dexmedetomidine 1 μg/kg was infused via a pump over 10 min.The onset time and duration of sedation were recorded,and the occurrence of adverse effects such as hypoxemia,bradycardia and hypotension was observed.Results There was no significant difference in the onset time of sedation and incidence of bradycardia among the 4 groups （P〉0.05）.Compared with group Ⅰ,the duration of sedation was significantly prolonged in Ⅱ-Ⅳ groups （P〈0.05）.Compared with Ⅱ and Ⅲ groups,the duration of sedation was significantly prolonged in group Ⅳ （P 〈 0.05）.The incidence of hypoxemia and hypotension was significantly higher in group Ⅳ than in Ⅰ-Ⅲ groups （P〈0.05）.Conclusion Dexmedetomidine-induced sedation is influenced by age factors,the duration of sedation induced by dexmedetomidine is prolonged,and the occurrence of adverse effects is increased,especially if the patients ≥ 90 yr of age.