Ultrasound-guided deep cervical plexus block is useful in the diagnosis and treatment of painful conditions subserved by the nerves of the deep cervical plexus, including posttrauma pain of the neck and supraclavicular fossa. This technique is also used to provide surgical anesthesia in the distribution of the deep cervical plexus for lesion removal, laceration repair, thyroid biopsy and thyroidectomy, deep lymph node biopsies and excisions, plastic surgery procedures of the neck, and carotid endarterectomy. Ultrasound-guided deep cervical plexus block may also be useful in the diagnosis and palliation of some cervical dystonias. Neurodestructive procedures of the deep cervical plexus may be indicated for pain of malignant origin that fails to respond to conservative measures.

The deep cervical plexus arises from fibers of the primary ventral rami of the first, second, third, and fourth cervical nerves (Fig. 22.1). Each nerve divides into an ascending and a descending branch providing fibers to the nerves above and below, respectively. This collection of nerve branches makes up the cervical plexus, which provides both sensory and motor innervation (Fig. 22.2) The most important motor branch of the cervical plexus is the phrenic nerve. The plexus also provides motor fibers to the spinal accessory nerve and to the paravertebral muscles and deep muscles of the neck. Each nerve, with the exception of the first cervical nerve, provides significant cutaneous sensory innervation. Terminal sensory fibers of the deep cervical plexus contribute fibers to the greater auricular and lesser occipital nerves. The fibers of the deep cervical plexus are in close proximity to the carotid artery and internal jugular vein, which provide excellent landmarks when performing ultrasoundguided deep cervical plexus block (Fig. 22.3).

The patient is placed in the supine position with the head turned away from the side to be blocked. Eleven milliliters of local anesthetic is drawn up in a 12-mL sterile syringe, and 40 to 80 mg of depot steroid is added to the local anesthetic if there is thought to be an inflammatory component to the patient’s pain symptomatology. The posterior border of the sternocleidomastoid muscle at the level of the superior thyroid cartilage (corresponding to approximately the C4 level) is then identified, and the skin overlying the area is prepped with antiseptic solution. A high-frequency linear ultrasound transducer is then placed over this point in a transverse oblique position at essentially a right angle to the posterior border of the sternocleidomastoid muscle (Fig. 22.4). At this point, the ultrasound transducer is slowly moved medially until the carotid artery and internal jugular vein are identified and their positions confirmed with power Doppler (Fig. 22.5). It is at this point that the deep cervical plexus is blocked utilizing an in-plane approach by placing a 22-gauge, 3½-inch styletted spinal needle at the posterior border of the sternocleidomastoid muscle and advanced under the tapered belly of the muscle toward the carotid artery keeping the needle tip above the more lateral internal jugular vein (see Figs. 22.3 and 22.6). When the needle tip is in proximity to the lateral border of the carotid artery, the stylet is removed, and after gentle aspiration, 9 to 10 mL of solution is injected in incremental doses under real-time ultrasound imaging. The needle is removed, and pressure is placed on the injection site to avoid hematoma or ecchymosis.