Bi-national survey of Korea and Japan related to the injection site for ultrasound-guided stellate ganglion blocks and anatomic comparisons using cadaver dissection

The aims of this study were to investigate the current clinical practice of ultrasound (US)guided stellate ganglion block (SGB) using a bi-national survey of Korea and Japan, and to clarify the anatomical relation of the cervical sympathetic trunk with the prevertebral fascia at the level of cervical vertebrae. The current clinical practice of US-guided SGB in Korea and Japan was investigated using an Internet survey, which received 206 (10.2%) replies from Korea and 97 (8.8%) replies from Japan. The survey questionnaire addressed the actual clinical practice for US-guided SGB, including where the tip of the injection needle is placed. Additionally, 16 half necks of 8 embalmed cadavers were used in an anatomical study. An in-plane needle approach technique and administering 5 ml of local anesthetic were preferred in both countries. However, the type of local anesthetic differed, being lidocaine in Korea and mepivacaine in Japan. The final position of the needle tip also clearly differed in an US image, being predominantly positioned above the prevertebral fascia in Korea (39.3%) and under the prevertebral fascia in Japan (59.8%). In all of the anatomic dissections, the cervical sympathetic trunk was over the prevertebral fascia at the level of the sixth vertebra and under the prevertebral fascia at the level of the seventh vertebra. These results are expected to improve the knowledge on the current clinical practice and to suggest future studies.