右美托咪定对罗哌卡因腋路臂丛神经阻滞时效的影响

目的探讨右美托咪定与局麻药罗哌卡因混合用于腋路臂丛阻滞对阻滞效果及有效时间的影响。方法择期或急诊在腋路臂丛神经阻滞下行上肢手术患者60例,ASAⅠ或Ⅱ级,随机均分为:罗哌卡因+右美托咪定组(RD组)和罗哌卡因组(R组)。以神经刺激器定位腋路臂丛神经主分支(桡神经、正中神经、尺神经和肌皮神经),RD组和R组分别注射0.375%罗哌卡因40ml+右美托咪定1ml(1μg/kg)和0.375%罗哌卡因40ml+生理盐水1ml,记录感觉和运动神经阻滞起效时间、作用时间、镇痛时间、首次疼痛VAS评分;记录入室时(T0)、阻滞后5min(T1)、10min(T2)、15min(T3)、30min(T4)、60min(T5)HR、MAP、SpO2,记录不良反应的发生情况。结果与R组比较,RD组感觉和运动阻滞起效时间缩短,作用时间及术后镇痛时间延长(P<0.05)。与R组比较,T1～T5时RD组HR减慢(P<0.05),MAP差异无统计学意义;与T0时比较,T2～T5时两组MAP下降,T1～T5时HR减慢(P<0.05),但仍在正常范围;两组患者阻滞后SpO2差异无统计学意义。RD组有5例患者心动过缓;两组患者未出现恶心、呕吐、低血压、低氧血症及局麻药中毒等不良反应。结论右美托咪定1μg/kg与局麻药混合应用于腋路臂丛神经阻滞可增强罗哌卡因的镇痛效果,缩短起效时间,延长作用时间及术后镇痛时间,但是易诱发心动过缓。

Comparison of adding dexmedetomidine to ropivacaine with ropivacaine alone for axillary brachial plexus block in upper limb surgeries

Objective To compare the efficacy of dexmedetomidine added to ropivacaine with ropivacaine alone in axillary brachial plexus block for upper limb surgeries.Methods Sixty ASA Ⅰ or Ⅱ patients scheduled for elective or emergency upper limb surgeries were randomly divided into 2 groups: group RD (n=30) and group R (n=30). The four main nerves in the axilla were identified using neural stimulation. In group RD, 40 ml of 0.375% ropivacaine+1 ml dexmedetomidine (1 μg/kg)and in group R, 40 ml of 0.375% ropivacaine + 1 ml saline were given, respectively. The onset of motor and sensory block and duration of block were recorded, HR, MAP, SpO2 were monitored. The complications were also recorded.Results Compared with group R, sensory and motor block onset times were shorter, sensory and motor blockade durations were longer in group RD (P<0.05). Duration of analgesia was longer in group RD than in group R (P<0.05). Compared with group R, the level of HR was significantly lower at T1-T5 in group RD. Compared with the baseline value, the level of HR was significantly lower at T1-T5, the level of MAP was significantly lower at T2-T5 (P<0.05). Bradycardia was observed in 5 patients in group RD.Conclusion Dexmedetomidine 1 μg/kg added to ropivacaine for axillary brachial plexus block shortens the onset time and prolongs the duration of the block and the duration of postoperative analgesia. However, dexmedetomidine may lead to bradycardia.