Abstract: ［Abstract］ Objective To observe the clinical efficacy and safety of the three different concentrations of mepivacaine hydrochloride during lumbar plexus block for patients undergoing single lower limb surgery. Methods Seventy-five adult patients with ASA Ⅰ- Ⅱ ，undergoing single lower limb surgery，were randomly divided into 3 groups including 0.25% ， 0.5% and 0.75% （n=25）， according to the concentration of mepivacaine. All patients were performed lumbar plexus block guided by ultrasound and nerve stimulator. 35 ml of 0.25% mepivacaine was injected in group 0.25% ，35ml of 0.5% mepivacaine in group 0.5% ，and 35 ml of 0.75% mepivacaine in group 0.75%. The onset time，duration，blocking extent and the occurrence of adverse events were recorded after lumbar plexus block. Results The onset time of sensory block in the three groups was 23.7±3.8 min，15.5±3.4 min，10.2±3.1 min，respectively， with significant difference between any two groups（P<0.01）. The duration of sensory and motor block in group 0.75% were longer than that of group 0.5%（P<0.01）. The onset time of motor block in group 0.75% was shorter than that of group 0.5%（P<0.01）. The blocking extent of group 0.5% or group 0.75% was greater than that of group 0.25%（P<0.05），with no significant difference between group 0.5% and group 0.75% . All patients in group 0.5% or group 0.75% completed the surgery only under nerve complete the surgery for poor outcome of nerve blockade. No complications such as local anesthetic poisoning， epidural block， postoperative neurological dysfunction were observed. Conclusion Mepivacaine hydrochloride can be used safely and effectively in lumbar plexus block for adult patients undergoing single lower limb surgery. And the concentration of 0.5%- 0.75% can achieve satisfactory blocking outcomes.

Key words: mepivacaine hydrochloride, concentration, lumbar plexus block, efficacy, safety

摘要： ［摘要］ 目的 观察三种浓度的盐酸甲哌卡因用于下肢手术患者腰丛阻滞的临床效果和安全性。方法 选择择期行单侧膝关节镜手术的成年患者 75 例，ASA Ⅰ～Ⅱ级，根据局麻药浓度的不同，分 0.25%组、0.5%组和 0.75%组，每组 25 例。三组均在超声和神经刺激仪引导下行单侧腰丛阻滞，分别注入浓度为 0.25%、0.5%、0.75% 的盐酸甲哌卡因 35 mL。观察腰丛阻滞的起效时间、持续时间、阻滞范围和并发症的发生情况。结果 0.25%组、0.5%组、0.75%组的感觉阻滞起效时间分别为 23.7±3.8 min、15.5±3.4 min、10.2±3.1 min，组间两两比较有统计学差异（P<0.01）。0.75%组感觉阻滞和运动阻滞的持续时间长于 0.5%组（P<0.01），运动阻滞的起效时间快于 0.5%组（P<0.01）。0.75%组和0.5%组的阻滞范围评分大于0.25%组（P<0.05），0.75%、0.5%组之间无统计学差异。0.75%、0.5%两组均在神经阻滞下完成手术；0.25%组的阻滞效果不佳，有 11 例患者（44%）需改为全身麻醉才完成手术。三组患者均未出现局麻药全身中毒、硬膜外阻滞、术后神经功能障碍等并发症。结论 盐酸甲哌卡因可安全有效地用于成年患者腰丛阻滞，0.5%～0.75%的浓度可获得满意的阻滞效果。

关键词: 腰丛阻滞, 盐酸甲哌卡因, 浓度, 安全性, 有效性