23
Complications of Stellate Ganglion Block (SGB)

Serdar Erdine MD, FIPP¹ and Peter S. Staats MD, MBA²

¹ Medical Faculty of Istanbul University, Istanbul Pain Center, Istanbul, Turkey
² World Institute of Pain, Atlantic Beach, FL, USA

Introduction

Stellate ganglion block (SGB) is one of the most common various sympathetic blocks used for the diagnosis and treatment of pain in the head and upper extremity. As a diagnostic tool, it is intended to separate sympathetically mediated pain states. If a patient has sustained relief with sympathetic blockade, consideration of repeated blocks is appropriate. If no relief is noted, alternative therapies are considered. As a therapeutic tool, it can provide limb salvage, long-term pain relief and improve perfusion.

Anatomy Location, Formation and Size of the Stellate Ganglion [1]

The stellate ganglion is 2.5 cm long, 1 cm wide and 0.5 cm thick and lies in front of the interspace between C7 and T1 vertebral bodies (Figures 23.1 and 23.2).

**Figure 23.1** This 3D-CT scan shows the course of the stellate ganglion. (*Source*: Courtesy of Raj, P. and Erdine, S. 2012 [1].)

**Figure 23.2** To identify the uncinate process. (*Source*: Courtesy of Raj, P. and Erdine, S. 2012 [1].)

Stellate ganglion is intimately related to the transverse processes and the prevertebral fascia anteriorly, the subclavian artery superiorly, the posterior aspect of the pleura posteriorly and the initial portion of the vertebral artery anteriorly.

Anatomically, the stellate ganglion is medial to the scalene muscles and lateral to the longus colli muscle. Other significant structures in close proximity to the stellate ganglion are the subclavian artery, inferior thyroid artery, intercostal arteries, and recurrent laryngeal nerve.

The vertebral artery transverses over the stellate ganglion and enters the vertebral foramen and is located posterior to the anterior tubercle of C6. The nerve roots of the brachial plexus, including C6, C7, C8, and T1, lie posterior to the respective tubercles (Figures 23.3–23.5).

**Figure 23.5** The superior, middle, and inferior cervical ganglion. (*Source* Courtesy of S. Erdine.)

**Figure 23.3** This 3D-CT scan shows the close relation between the vertebral artery and stellate ganglion. (*Source*: Courtesy of Raj, P. and Erdine, S. 2012 [1].)

**Figure 23.4** This MRI shows the structures in close proximity with the stellate ganglion. (*Source*: Courtesy of Raj, P. and Erdine, S. 2012 [1].)

Indications

Pain Syndromes

Complex regional pain syndrome type I and type II
Vascular headaches
Cluster headaches
Acute herpes zoster (shingles)
Postherpetic neuralgia
Phantom limb pain
Painful neoplastic disorders
Postradiation neuritis
Intractable angina pectoris not responsive to more conservative options
Pain from cranial nerve disorders.

Vascular Insufficiency

Raynaud’s disease
Raynaud’s phenomenon
Frost bite
Vasospasm
Occlusive vascular disease
Embolic vascular disease (upper extremity arterial embolism)
Scleroderma
Hyperhidrosis
Ventricular arrhythmias
Inadvertent intra-arterial injection.

Contraindications

Local or systemic infection
Coagulopathy
Asthma (relative contraindication)
Pneumothorax and or pneumonectomy on the contralateral side; if a pneumothorax occurs on the opposite side of an existing pneumothorax it can be life threatening
Contralateral phrenic nerve injury
Recent myocardial infarction
Contralateral recurrent laryngeal nerve injury with vocal cord paralysis
Previous anterior lower cervical surgery (relative)
Patient refusal.

Technique

There are multiple approaches for SGB or lesioning:

Blind
Fluoroscopic
Ultrasonographic approach

Fluoroscopic Approach to the Stellate Ganglion

With the cervicothoracic ganglion (stellate ganglion lies between the C7 and T1 levels), the most commonly used approach is the C6 or C7 paravertebral approach depending on volume to drive the anesthetic to the stellate ganglion. This approach helps mitigate the risks of pneumothorax.

The patient is placed in supine position on the table, the head is fixed by adhesive tape, an intravenous (IV) access is obtained, oxygen is administered by a nasal canula and vital signs are monitored.

The C-arm is placed in posteroanterior view first and the vertebral body of C6 or C5 is identified (Figure 23.6). The target is the junction of the transverse process. After infiltrating the skin over the entry point with local anesthetic, a 5–10 cm needle with an extension line is directed to the target point until a bony contact is made either at a transverse process or the anterior surface of the vertebral body (Figure 23.7). The needle should stay on the ventrolateral side of the vertebral body. Using ultrasound (US), the tissue plane and indeed the cervicothoracic ganglion itself can be visualized, as well as vertebral inferior thyroid arteries and the venous system.

**Figure 23.7** The needle should stay on the ventrolateral side of the vertebral body.

The longus colli muscle is located over the lateral aspect of the vertebral body and is on the medial aspect of the tranverse process. Care should be taken to stay on the bone, to avoid injection into the longus colli muscle. If a paresthesia of the upper extremity is elicited during needle placement, one must assume the needle has penetrated too deeply and encountered a nerve root of the brachial plexus. The needle should be withdrawn and repositioned. After the aspiration test, if it is negative, inject 3–5 ml of contrast material under uninterrupted live imaging at C6–T1 level. If blood is aspirated, the needle should be repositioned (Figure 23.8).

**Figure 23.8** Spread of the contrast material in PA view.

Then, the C-arm is turned laterally. The contrast material should spread in the retropharyngeal space anterior to the longus colli and anterior scalene muscles (Figure 23.9).

**Figure 23.9** Spread of the contrast material in lateral view.

If an irregular image appears, then the contrast material is injected into the muscle. If there is a resistance to injection, one should suspect that the needle is within the periosteum of the bone. If the needle is advanced medially or deeper, there is a risk of entering the epidural or subarachnoid space. The contrast material should be checked for appearance in the epidural or subarachnoid space. After confirming the correct placement of the needle, 5 ml of 0.5 % bupivacaine or 1% lidocaine is injected. If planned, radiofrequency (RF) lesioning is performed as described previously [1].

One should avoid the use of neurolytic solutions in non-cancer pain.

**Figure 23.6** The target is the junction of the vertebral transverse process. A lateral view (Figure 23.12) is used to count the vertebral levels.

**Figure 23.12** Recurrent laryngeal nerve [2].

Ultrasound Approach to the SGB

US has more recently been advocated for performance of SGB. Since the vascular supply is not identified with traditional radiographic images, use of US can identify possible vascular interference with accessing the sympathetic chain. Similar techniques are used, however, US is used as the guide (Figures 23.10 and 23.11).