Stellate Ganglion Block

Written by Staff | 30 October 2011

When pain management with medications is unsuccessful, interventional nerve blocks can be used to treat certain types of acute and chronic pain. In nerve blocks, a combination anesthetic and steroid solution is injected into nervous tissue to reduce inflammation and block the transmission of pain signals to the brain¹.

Some nerve blocks target a specific segment of the nervous system known as the sympathetic nervous system. The sympathetic nervous system isn’t under voluntary control and contains many neural pathways that communicate pain to the brain; it also controls many “fight or flight” responses from the brain, such as increases in heart rate and pupil dilation.

A stellate ganglion block (SGB) targets clusters of sympathetic nerves, or ganglia, that participate in the communication of pain signals from the head, neck and upper extremities¹. The SGB is an important treatment for a condition known as complex regional pain syndrome (CRPS). CRPS affects the extremities with a variety of symptoms including pain, swelling, and skin and bone changes, and most commonly occurs after significantly stressful medical events such as a heart attack or stroke³. The SGB has been reported to provide effective pain relief for this condition, and may even help reverse the course of early disease. These nerve blocks have also been used to treat the painful symptoms of shingles and sympathetic dystrophy, as well as increase regional blood flow^{1, 2}.

The Procedure

The spine is divided into four major regions; the cervical (neck), thoracic (upper back), lumbar (lower back) and sacral (hip/tailbone) regions. During a stellate ganglion block procedure, the side of the neck is numbed with a local anesthetic and a needle is inserted and guided just adjacent to the lowest cervical vertebrae (C7)^{1, 2}.

To accomplish this, the patient lies on their back and slightly extends the neck allowing a doctor to feel for vertebral landmarks that will help determine proper needle insertion². Once inserted, a physician would traditionally attempt to guide the needle to the correct position based on the vertebral landmarks, however without definitive guidance there is a significant risk of injecting the anesthetic solution into an artery or other critical neck structure causing complications¹. Complications can include blocking the wrong nerves, fainting, seizures/convulsion, paralysis, heart attack, and in some cases death^{1, 2}. Instead physicians now use fluoroscopy, essentially a real-time x-ray, to safely guide the needle through internal tissues.

The procedure is generally performed every 1–4 days, and can be repeated between 6–12 times. Pain relief can last several days, however treatment is discontinued after the first or second injection if pain relief isn’t quickly experienced³.

References

1. Zhou, Y. (2008). Principles of Pain Management. Bradley: Neurology in Clinical Practice, 5th Ed. MD Consult Web site, Core Collection.
2. Wedel, D.; Horlocker, T. (2009). Blocks of the Head and Neck. Miller: Miller’s Anesthesia, 7th Ed. MD Consult Web site, Core Collection.
3. Sheon, R. (2010). Prevention and management of complex regional pain syndrome in adults. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA.