ISSN: 2155-6148
Mattias Casutt, Kathrin Job, Jonas Beutler, Jan Duwe, Patrick Veit and Christoph Konrad
Background: The case series illustrates the spread of local anesthetic resulting from a standardized singleinjection technique of intermediate cervical plexus block before carotid endarterectomy.
Methods: 14 consecutive patients scheduled for elective carotid endarterectomy were included. Standardized intermediate cervical plexus block was performed on the level of C5/C6 at the posterior border of the sternocleidomastoid muscle. A mixture of 20ml Ropivacaine 0.75%, 20ml Prilocaine 1% and 8ml Iopromidum (iodine-concentration 300mg/ml) was injected. The direction of the injection was defined as cranial, medial and caudal behind the sternocleidomastoid muscle in a depth of 1-1.5cm. Subsequently, after 30minutes, a CT-scan of the head and neck region and upper thorax was completed to evaluate the distribution of the injectate in a threedimensional reconstruction.
Results: The spread of the injectate ranged from the top edge of cervical vertebral body 1 to the bottom edge of thoracic vertebral body 3. The reproduced volume of 75260(5407)mm³ (SD) possessed a maximal craniocaudal spread of 125(24)mm in the sagital plane 81(13)mm and in the coronal plane 43(13)mm. The minimal distance to the skin was 0.9(1.0)mm. The patients judged the block to be sufficient under our protocol. Therefore, no patient required conversion to general anesthesia.
Conclusion: Intermediate cervical plexus block is associated with an extensive spread of injectate that transverses the deep cervical fascia. The distribution pattern and the sensory and motor blockade level of this intermediate cervical plexus block seems to be sufficient for surgery and is of minor risk compared to the deep cervical plexus block.