右美托咪定用于锁骨上臂丛神经阻滞对正中神经体感诱发电位的影响

Effect of dexmedetomidine on median nerve somatosensory evoked potential in supraclavicular brachial plexus block

目的:研究右美托咪定用于锁骨上臂丛神经阻滞对正中神经体感诱发电位的影响。方法 :择期行前臂骨折手术患者60例,随机分为罗哌卡因组(R组,n=30)和罗哌卡因复合右美托咪定组(RD组,n=30),患者均行超声引导下锁骨上臂丛神经阻滞麻醉。R组给予0.5%罗哌卡因20 m L,RD组给予含有右美托咪定1μg/kg的0.5%罗哌卡因20 m L。观察不同时间点的心率、平均动脉压及脉搏血氧饱和度等生命体征;记录感觉和运动阻滞的起效时间及持续时间;记录神经阻滞前、阻滞后48 h正中神经体感诱发电位的潜伏期和波幅;观察并记录不良反应。结果:与R组比较,RD组感觉和运动阻滞的起效时间均缩短(均P<0.05),感觉和运动持续时间均延长(P<0.05);与阻滞前比较,RD组中阻滞后48 h后正中神经体感诱发电位的潜伏期和波幅差异均无统计学意义(均P>0.05)。与阻滞前比较,RD组阻滞48 h后正中神经体感神经诱发电位的潜伏期和波幅差异均无统计学意义(均P>0.05)。结论:右美托咪定用于超声引导下锁骨上臂丛神经阻滞时,可有效增强罗哌卡因的局麻效果,且对阻滞后臂丛神经功能恢复无损害。

Objective： To investigate the effect of dexmedetomidine on median nerve somatosensory evoked potential（MNSEP） in supraclavicular brachial plexus block. Methods： A total of 60 patients scheduled for elective forearm surgery were randomized to receive ultrasound-guided supraclavicular brachial plexus block using 0.5% ropivacaine 20 m L with 1 μg/kg dexmedetomidine administered perineurally（RD group） or none（R group）. heart rate（HR）, mean arterial pressure（MAP） and pulse oxygen saturation（ Sp O2） were monitored and recorded at several time points. Patients were observed for onset and duration of sensory and motor blockade, MNSEP latency and amplitude before and 48 h after supraclavicular brachial plexus block, andadverse effects.Results： Group RD showed a statistically significant shorter time to onset of sensory and motor blockade（P0.05）. The duration of sensory, as well as motor, block was significantly prolonged in the RD group（ P 0. 05）. There was no significant difference between MNSEP latency（P 0.05）, as well as amplitude（P 0.05）, recorded respectively before and 48 h after never block.Conclusion： Dexmedetomidine has no harmful effect on brachial plexus nerve in recovering from the blockade, while providing quicker onset of anesthesia and longer duration of analgesia.