What is a stellate ganglion block?

Stellate Ganglion Block: Overview and Clinical Applications

A stellate ganglion block is a minimally invasive procedure that involves injecting local anesthetic near the stellate ganglion to produce sympathetic blockade of the head, neck, and upper extremity, primarily used for treating complex regional pain syndrome (CRPS) and other sympathetically mediated pain conditions. 1, 2

Anatomy and Procedure

The stellate ganglion:

• Located at the level of C6-C7 vertebrae, formed by fusion of inferior cervical and first thoracic sympathetic ganglia
• Positioned anterior to the transverse process of C7, medial to scalene muscles, lateral to longus colli muscle, esophagus, trachea, and recurrent laryngeal nerve
• Superior to subclavian artery and posterior to vertebral vessels 3

Technique options:

• Traditional landmark-based approach (paratracheal access)
• Image-guided approaches:
  • Ultrasound guidance (preferred to visualize vascular structures and soft tissues)
  • Fluoroscopy guidance
  • CT or MRI guidance (less common) 3, 2

Clinical Indications

Primary indications:

• Complex Regional Pain Syndrome (CRPS) Types I and II
• Sympathetically mediated pain in the head, neck, and upper extremity 1, 4

Secondary indications:

• Raynaud's disease
• Hyperhidrosis
• Arterial embolism in the upper extremity
• Vascular disorders affecting upper extremity circulation 4, 5

Disputed or emerging applications:

• Acute hearing loss
• Retinal arterial spasms
• Psychological disorders
• Sleep disorders
• Certain immunological conditions 5, 6

Efficacy and Duration

• The American Society of Anesthesiologists (ASA) and American Society of Regional Anesthesia (ASRA) guidelines recommend stellate ganglion blocks as components of multimodal treatment for CRPS when used in the presence of consistent improvement and increasing duration of pain relief 1
• Pain relief is typically short-term, requiring repeated procedures for sustained benefit
• Not recommended for long-term treatment of non-CRPS neuropathic pain according to ASA/ASRA guidelines 1

Complications and Safety Considerations

Potential complications include:

• Medication-related/systemic side effects (68.4% of reported complications)
• Procedure-related/local side effects (31.5% of reported complications)
• Serious but rare complications:
  • Airway obstruction from hematoma (one reported fatal case)
  • Infection (rare reports of epidural abscess)
  • Pneumothorax
  • Recurrent laryngeal nerve injury causing hoarseness
  • Intravascular injection
  • Spinal or epidural injection 2

Safety measures:

• Use of image guidance (ultrasound or fluoroscopy) to reduce complications
• Standard ASA monitoring during the procedure
• Immediate access to resuscitation equipment
• Proper patient selection and informed consent 2, 5

Current Practice Recommendations

1. Stellate ganglion blocks should be used as part of a multimodal treatment approach, not as standalone therapy
2. For CRPS, stellate ganglion blocks may be used when consistent improvement is observed with repeated blocks 1
3. Ultrasound guidance is increasingly preferred over blind technique to improve safety and efficacy 3, 2
4. Not recommended for long-term treatment of non-CRPS neuropathic pain 1
5. Patients should be informed about potential complications and alternative treatments before obtaining informed consent 5

Emerging Approaches

Novel approaches are being developed to improve safety and efficacy:

• Ultrasound-guided supraclavicular approach to stellate ganglion block
• Integration with broader pain management strategies
• Application in non-traditional conditions beyond pain management 4, 6

By understanding the indications, technique, efficacy, and safety profile of stellate ganglion blocks, clinicians can appropriately incorporate this procedure into comprehensive pain management strategies for selected patients.