Hara Kaoru, Sakura Shinichi, Yokokawa Naomi
Department of Anesthesiology, University Hospital, Shimane University School of Medicine, Izumo, Japan.
J Anesth. 2014 Aug;28(4):524-31. doi: 10.1007/s00540-013-1746-x. Epub 2013 Nov 20.
Nerve stimulation may be combined with ultrasound imaging for a block of deeply located nerves such as the sciatic nerve in the subgluteal region. At present, it is unknown how the use of nerve stimulation affects blockade after this nerve block. We retrospectively compared the effects of the two types of motor response and those of minimal evoked current above and below 0.5 mA on ultrasound-guided subgluteal sciatic nerve block using mepivacaine or ropivacaine, two local anesthetics with different onset time and duration.
We reviewed records and video images of patients who, from April 2008 until October 2011, received ultrasound-guided subgluteal sciatic nerve block combined with nerve stimulation using 20 ml of either 1.5 % mepivacaine with 1:400,000 epinephrine or 0.5 % ropivacaine. Sensory and motor blockade data for 30 min after the block and for the duration of the blockade were gathered. Patients for whom any data were missing, the video image was poor, and/or intraneural injection was observed during the block were excluded from the study. The same data were compared in two ways: regarding the motor response pattern between the response of the tibial nerve and the common peroneal nerve, and regarding the minimal current between low current (< 0.5 mA) and high current (≥0.5 mA). The primary endpoints were the onset and duration of blockade of the sciatic nerve block.
We analyzed the data of 170 and 99 patients who received mepivacaine and ropivacaine, respectively. The progress of sensory and motor blockade as well as block duration was similar between different motor response patterns after both anesthetics. The proportion of patients who developed sensory block of the tibial nerve and motor block at 30 min was higher in the low minimal current group than in the other group receiving mepivacaine. Patients in the former group also had longer block duration. With ropivacaine, complete motor blockade was present at 30 min in a higher proportion of patients after lower minimal evoked current than after higher minimal evoked current.
When ultrasound-guided subgluteal sciatic nerve block was conducted with nerve stimulation, the motor response pattern did not markedly affect the progress of sensory or motor blockade or block duration. Lower minimal evoked current was associated with faster onset in sensory and motor block and longer block duration after mepivacaine and faster onset in motor block after ropivacaine. The clinical significance of this, however, has yet to be determined.
神经刺激可与超声成像相结合，用于阻滞深部神经，如臀下区域的坐骨神经。目前，尚不清楚神经刺激的使用对该神经阻滞后的阻滞效果有何影响。我们回顾性比较了两种运动反应类型以及0.5 mA上下的最小诱发电流对使用甲哌卡因或罗哌卡因（两种起效时间和持续时间不同的局部麻醉药）进行超声引导下臀下坐骨神经阻滞的影响。
我们回顾了2008年4月至2011年10月期间接受超声引导下臀下坐骨神经阻滞并结合神经刺激的患者的记录和视频图像，这些患者使用了20 ml的1.5%甲哌卡因加1:400,000肾上腺素或0.5%罗哌卡因。收集了阻滞后30分钟以及整个阻滞期间的感觉和运动阻滞数据。任何数据缺失、视频图像不佳和/或在阻滞期间观察到神经内注射的患者被排除在研究之外。以两种方式比较相同的数据：关于胫神经和腓总神经反应之间的运动反应模式，以及关于低电流（<0.5 mA）和高电流（≥0.5 mA）之间的最小电流。主要终点是坐骨神经阻滞的起效时间和持续时间。
我们分别分析了170例接受甲哌卡因和99例接受罗哌卡因患者的数据。两种麻醉药不同运动反应模式后的感觉和运动阻滞进展以及阻滞持续时间相似。低最小电流组在30分钟时出现胫神经感觉阻滞和运动阻滞的患者比例高于接受甲哌卡因的另一组。前一组患者的阻滞持续时间也更长。使用罗哌卡因时，较低最小诱发电流组在30分钟时完全运动阻滞的患者比例高于较高最小诱发电流组。
在进行超声引导下臀下坐骨神经阻滞并结合神经刺激时，运动反应模式并未显著影响感觉或运动阻滞的进展或阻滞持续时间。较低的最小诱发电流与甲哌卡因后感觉和运动阻滞的更快起效以及更长的阻滞持续时间相关，与罗哌卡因后运动阻滞的更快起效相关。然而，其临床意义尚待确定。
