Gorsewski G, Dinse-Lambracht A, Tugtekin I, Gauss A
Klinik für Anästhesiologie, Universitätsklinikum Ulm, Deutschland.
Anaesthesist. 2012 Aug;61(8):711-21. doi: 10.1007/s00101-012-2045-x.
Ever since the use of ultrasound guidance in regional anesthesia became more and more popular in recent years, it seemed obvious that so-called intraneural puncture and injection of local anesthetics was much more common than previously assumed. However, neurologic damage was not seen very often. The ultrasound-guided imaging of the nerves showed that intraneural injection has to be seen as an overall term. This term must be characterized in more detail in accordance with nerve anatomy and morphology. Various studies demonstrated that if intraneural puncture occured the needle usually took a path away from the fascicles (intraneural perifascicular), while intraneural transfascicular puncture seemed relatively rare and intraneural intrafascicular placement of the needle even more uncommon. As long as the needle is placed intraneurally but in an extrafascicular fashion a safe injection and the absence of neurologic damage can be assumed. However, if nerve fascicles are affected neurologic dysfunction can occur. In studies investigating the minimal effective local anesthetic volume needed for successful nerve block, a relevant reduction of injected volume was still achieved by intentionally applying the local anesthetic circumferentially around the outermost nerve layer rather than injecting it into neural structures. As an intraneural -intrafascicular injection carries the risk of nerve injury associated with a decrease in quality of life, the potential of ultrasound guidance in regional anesthesia should be considered. Circumferential administration of local anesthetic rather than creating a single point injection appears to be advantageous.
近年来，自从超声引导在区域麻醉中的应用越来越普遍以来，所谓的神经内穿刺和局部麻醉药注射似乎比以前认为的更为常见。然而，神经损伤并不常见。神经的超声引导成像显示，神经内注射必须被视为一个总称。这个术语必须根据神经解剖学和形态学进行更详细的描述。各种研究表明，如果发生神经内穿刺，针通常会偏离束膜走行（神经内束膜周围），而神经内跨束膜穿刺似乎相对少见，针在神经内束膜内的放置则更为罕见。只要针放置在神经内但以束膜外的方式，就可以认为注射是安全的且不会发生神经损伤。然而，如果神经束膜受到影响，就可能发生神经功能障碍。在研究成功进行神经阻滞所需的最小有效局部麻醉药体积时，通过有意将局部麻醉药围绕最外层神经层周向注射而不是注入神经结构中，仍能显著减少注射体积。由于神经内束膜内注射存在神经损伤风险并会降低生活质量，因此应考虑超声引导在区域麻醉中的潜力。局部麻醉药的周向给药而非单点注射似乎更具优势。
