Lu I-Chen, Hsu Hung-Te, Soo Lee-Ying, Lu David Vi, Chen Tai-I, Wang Jhi-Joung, Chu Koung-Shing
Department of Anesthesiology, Kaohsiung Medical University Chun-Ho Memorial Hospital, Kaohsiung, Taiwan, ROC.
Acta Anaesthesiol Taiwan. 2007 Jun;45(2):73-8.
Surface anatomic landmarks have traditionally been used to locate the brachial plexus in the interscalene groove. Head rotation can affect the orientation of neck vessels and may possibly affect the brachial plexus. The optimal degree of head rotation has been specified for better internal jugular vein cannulation but not for interscalene brachial plexus block. The purpose of this study was to evaluate the influence of head rotation on interscalene brachial plexus block.
We simulated the needle insertion in interscalene approach to brachial plexus with the ultrasound probe to mimic the needle in the manner of actual block in 53 volunteers. Ultrasound-derived measurements were recorded to evaluate the influence of head rotation on the approach including deviation from the imitative needle path to plexus center, depth of brachial plexus and vessel intersection.
Medial deviation of the imitative needle path to the center of brachial plexus was found from all angles of head rotation. Increased head rotation angle of 0 degree, 15 degrees, 30 degrees, 45 degrees and 60 degrees from the midline was associated with increasing medial deviation. The brachial plexus became more superficial if head rotation was over 30 degrees than within the realm of 15 degrees. The likelihood of the stimulated needle path intersecting the internal jugular vein was lower than 5% for head rotation within 30 degrees and would become significantly higher for head rotation over 45 degrees.
Whenever we perform interscalene brachial plexus block, the head rotation angle should not exceed 30 degrees. The measured medial deviation of surface landmark should be considered when it is used to approach interscalene brachial plexus.
传统上，体表解剖标志用于在斜角肌间隙定位臂丛神经。头部旋转会影响颈部血管的方向，可能也会影响臂丛神经。已明确了最佳头部旋转角度以利于更好地进行颈内静脉置管，但尚未明确用于斜角肌臂丛神经阻滞的最佳头部旋转角度。本研究的目的是评估头部旋转对斜角肌臂丛神经阻滞的影响。
我们用超声探头模拟在斜角肌间隙进行臂丛神经阻滞时的进针情况，对53名志愿者以实际阻滞的方式模拟进针。记录超声测量结果，以评估头部旋转对进针路径的影响，包括从模拟针道到神经丛中心的偏差、臂丛神经深度和血管交叉情况。
在所有头部旋转角度下，均发现模拟针道向臂丛神经中心内侧偏移。从中线开始，头部旋转角度增加0度、15度、30度、45度和60度时，内侧偏移随之增加。如果头部旋转超过30度，臂丛神经会比在15度范围内时更表浅。头部旋转30度以内时，刺激针道与颈内静脉交叉的可能性低于5%，而头部旋转超过45度时，该可能性会显著增加。
在进行斜角肌臂丛神经阻滞时，头部旋转角度不应超过30度。使用体表标志进针时，应考虑测量得到的内侧偏移。
