低电流神经刺激诱发股四头肌肌颤搐辅助超声引导腰丛阻滞的效果

Efficacy of quadriceps femoris fasciculation induced by low-current nerve stimulation when used to assist ultrasound-guided lumbar plexus block

【摘要】目的评价低电流神经刺激诱发股四头肌肌颤搐辅助超声引导腰丛阻滞的效果。方法选择行单侧膝关节镜手术患者100例，性别不限，年龄18～45岁，ASA分级I或Ⅱ级，体重50～85kg。采用随机数字表法分为2组（n=50）：神经刺激器辅助超声组（su组）和超声组（u组）。2组均采用“三叶草”法超声引导腰丛阻滞，SU组穿刺时连接神经刺激器，电流强度0．35mA，频率1Hz，诱发股四头肌肌颤搐后注射0．5％罗哌卡因0．4ml／kg，U组通过超声判断针尖达腰丛神经后注射0．5％罗哌卡因O．4ml／kg。记录穿刺时间、进针深度、阻滞起效时间和有效情况，采用改良膝关节评分法评估运动阻滞程度，阻滞后24h内记录并发症的发生情况。结果与u组比较，SU组阻滞起效时间缩短，有效率升高，运动阻滞程度加重（P〈0．05），穿刺时间和进针深度差异无统计学意义（P〉0．05）。2组均未见相关并发症发生。结论低电流（0．35mA）神经刺激诱发股四头肌肌颤搐辅助定位，可改良超声引导腰丛阻滞的效果。

Objective To evaluate the efficacy of quadriceps femoris fasciculation induced by low- current nerve stimulation when used to assist ultrasound-guided lumbar plexus block. Methods One hun- dred patients of both sexes, aged 18-45 yr, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ , weighing 50-85 kg, scheduled for elective unilateral knee arthroscopy, were selected and randomly divided into 2 groups （n= 50 each） using a random number table： ultrasound assisted by nerve stimulator group （group SU） and ultrasound group （group U）. The ＂shamrock method＂ was used to perform the ul- trasound-guided lumbar plexus block in two groups. In group SU, the nerve stimulator with current 0.35 mA and frequency 1 Hz was used in the process of puncture, and 0.5% ropivacaine 0.4 ml/kg was admin- istrated when quadriceps femoris fasciculation was induced. In group U, when the tip of the nerve stimula- ting needle was located around the lumbar plexus, which was confirmed by ultrasound, 0.5% ropivacaine 0.4 ml/kg was administrated. The time of puncture, depth of needle insertion, onset time of block and ef- fective block were recorded. Motor block was assessed using the modified knee score, and the development of complications was recorded within 24 h after block. Results Compared with group U, the onset time of block was significantly shortened, the rate of effective block was increased, the degree of motor block was aggravated （P〈0.05） , and no significant change was found in the time of puncture or depth of needle in- sertion in group SU （P〉0.05）. No complications were observed in two groups. Conclusion Low-current （0.35 mA） nerve stimulation-induced quadriceps femoris tasciculation when used to assist location can im- prove the efficacy of ultrasound-guided lumbar plexus block.