A stellate ganglion block is a medical procedure involving an injection of medication into a specific nerve cluster in the neck. This therapeutic intervention aims to alleviate certain types of pain and address various conditions that involve the sympathetic nervous system. It serves as a method to temporarily interrupt nerve signals, potentially providing relief from discomfort and improving function in affected areas of the body. The procedure is typically performed by pain management specialists.
Understanding the Stellate Ganglion
The stellate ganglion is a collection of sympathetic nerves located on either side of the voice box in the neck. These nerves are part of the sympathetic nervous system, which regulates involuntary bodily functions like blood flow, heart rate, and sweating.
The stellate ganglion controls these functions in the head, neck, upper chest, and upper extremities, including the arm. By influencing blood vessel constriction and dilation, it affects blood supply to these regions. It helps maintain balance within the body’s involuntary responses.
How the Block Works
A stellate ganglion block involves injecting a local anesthetic, and sometimes a steroid, near the stellate ganglion in the neck. This injection temporarily blocks the sympathetic nerve signals that pass through this ganglion. The medication spreads around the nerves, interrupting their usual activity.
This interruption of nerve signals can lead to several therapeutic effects. It may reduce pain, decrease swelling, improve blood flow, and normalize sweating in the affected areas. This temporary blockade allows for a resetting of nerve activity, which helps alleviate symptoms.
Conditions Treated with Stellate Ganglion Block
A stellate ganglion block is often used to treat conditions characterized by sympathetic nervous system dysfunction or chronic pain in the upper body. One common application is for Complex Regional Pain Syndrome (CRPS), a chronic pain condition often presenting with burning sensations, numbness, tingling, and skin changes in the arm or hand. It is also used for causalgia (intense burning pain).
The procedure may also provide relief for phantom limb pain, a sensation of pain in a limb that has been amputated. Additionally, it can be used for certain vascular conditions that affect blood flow in the upper extremities, such as Raynaud’s syndrome, scleroderma, and frostbite. Some studies also explore its use for post-herpetic neuralgia (nerve pain after shingles) and persistent hot flashes.
What to Expect During and After the Procedure
Before a stellate ganglion block, patients will have their blood pressure checked and may be asked to sign a consent form. An intravenous (IV) line might be started, especially if sedation is requested. Patients typically lie on their back on an X-ray table, and the neck area is cleansed with an antiseptic solution.
During the procedure, a physician will identify the injection site using imaging guidance for precise needle placement. A thin needle is then inserted to inject the local anesthetic near the voice box. The injection takes only a few minutes, with the medication taking 10 to 20 minutes to take full effect. Patients are monitored for a period, typically 40 to 60 minutes, in a recovery area, where pulse, blood pressure, and temperature are observed. Common temporary side effects on the same side as the injection can include a droopy eyelid, a bloodshot eye, nasal congestion, and a warm sensation in the arm, usually lasting about 4 to 6 hours.
Potential Considerations
While generally safe, a stellate ganglion block carries some potential considerations, though complications are infrequent. Rare risks include infection, bleeding, nerve damage, or a collapsed lung (pneumothorax). There is also a slight risk of the medication entering a blood vessel, potentially leading to a seizure, or affecting adjacent nerves, causing temporary arm numbness.
The procedure may not be recommended for individuals with an active infection, a fever, high blood pressure, or those currently taking blood thinners. The effects are temporary, and pain relief duration varies among individuals. For some conditions, a series of blocks administered 1 to 2 weeks apart may be recommended for more prolonged relief.