PERIPHERAL NERVE BLOCKS OF THE TRUNK
Superficial Cervical Plexus Block
The superficial cervical plexus block provides cuta-neous analgesia for surgical procedures on the neck, anterior shoulder, and clavicle. It is helpful to iden-tify and avoid the external jugular vein. The cervi-cal plexus is formed from the anterior rami of C1–4, which emerge from the platysma muscle posterior to the sternocleidomastoid (Figure 46–60). It supplies sensation to the jaw, neck, occiput, and areas of the chest and shoulder.
The patient is positioned supine with the head turned away from the side to be blocked. The ster-nocleidomastoid muscle is identified and its lateral edge marked. At the junction of the upper and mid-dle thirds, a short (5-cm) block needle is inserted,
directed cephalad toward the mastoid process, and 5 mL of local anesthetic is injected in a sub-cutaneous plane. The needle is turned to advance it in a caudad direction, maintaining a path along the posterior border of sternocleidomastoid. An additional 5 mL of local anesthetic is infiltrated subcutaneously.