Department of Anesthesiology, Shimane University School of Medicine, Izumo City, Japan.
Reg Anesth Pain Med. 2012 May-Jun;37(3):289-93. doi: 10.1097/AAP.0b013e31824bde5c.
The present study was conducted to determine the incidence of unintentional intraneural injection during ultrasound-guided subgluteal sciatic nerve block using a low-frequency transducer. We also observed the effects of intraneural injection using ropivacaine and mepivacaine.
Enrolled in the study were 325 patients undergoing arthroscopic knee surgery, who each received a subgluteal sciatic nerve block under ultrasound guidance using 1.5% mepivacaine with 1:400,000 epinephrine or 0.5% ropivacaine. A block needle was inserted in-plane with the ultrasound transducer (5-2 MHz curved array) and advanced slowly under real-time ultrasound guidance until it was positioned immediately adjacent to the nerve. Twenty milliliters of either anesthetic was then injected to produce a circumferential spread. An ultrasound video was recorded and used to examine whether the local anesthetic was injected intraneurally. Sensory and motor blockade was evaluated for 30 mins after completion of the block. Duration of the block and any neurologic complications were also examined.
Intraneural injection was detected in 46 patients (16.3%; 95% confidence interval, 12.3%-20.3%). Onset of sensory and motor blockade was significantly faster in patients with intraneural injection than those without either mepivacaine or ropivacaine. Duration of sensory blockade was similar between patients with and without intraneural injection. No patient developed postoperative neurologic complications.
Unintentional intraneural injection occurred at an incidence rate of 16.3% for the ultrasound-guided subgluteal approach to the sciatic nerve. Intraneural injection of mepivacaine or ropivacaine hastened the onset of blockade but did not affect block duration, and it did not result in clinical neural injury in our small sample of patients.
本研究旨在确定使用低频换能器行超声引导下臀部坐骨神经阻滞时意外发生神经内注射的发生率，并观察罗哌卡因和甲哌卡因的神经内注射效果。
本研究纳入了 325 例行关节镜膝关节手术的患者，他们均在超声引导下使用 1.5%甲哌卡因（含 1：400，000 肾上腺素）或 0.5%罗哌卡因行臀部坐骨神经阻滞。将阻滞针与超声换能器（5-2MHz 弧形阵）平面内进针，并在实时超声引导下缓慢推进，直到其紧贴神经。然后注入 20ml 局麻药，以产生环形扩散。记录超声视频并检查局麻药是否注入神经内。阻滞完成后 30 分钟评估感觉和运动阻滞情况。还检查了阻滞持续时间和任何神经并发症。
46 例（16.3%；95%置信区间，12.3%-20.3%）患者发生神经内注射。与未使用甲哌卡因或罗哌卡因的患者相比，神经内注射患者的感觉和运动阻滞的起始时间明显更快。有神经内注射和无神经内注射患者的感觉阻滞持续时间相似。没有患者发生术后神经并发症。
超声引导下臀部坐骨神经阻滞时，意外发生神经内注射的发生率为 16.3%。甲哌卡因或罗哌卡因的神经内注射虽加快了阻滞的起始，但并未影响阻滞持续时间，且在我们的小样本患者中并未导致临床神经损伤。
