Sympathetic Nerve Block
Diagnosing the Problem
A sympathetic nerve block is a special test. It helps your doctor find the cause of your symptoms. During the test, medication is injected near your spine. This “blocks” the sympathetic nerves in that region. If these nerves are causing your problem, the injection will relieve your symptoms for a while. Your symptoms may include burning, pain, or tingling in your arms and hands or legs and feet.
To get ready for the block, do the following:
- At least a week before the block, tell your doctor what medications you take (including aspirin). Ask whether you should stop taking any of them before treatment.
- Tell your doctor if you are pregnant or allergic to any medications.
- Stop eating or drinking 8 hours before you check in for your block, or as directed.
- If asked, bring x-rays, MRIs, or other tests with you on the day of the block.
The injection is done in a hospital or surgery center. You’ll be asked to fill out some forms, including a consent form. You may also be examined. You may be given an IV (intravenous) line for fluids and medications
During the Procedure
To help you relax, medication may be given through the IV line. You will lie on an exam table on your stomach, back, or side. This depends on where you will be injected. During your block:
- The skin over the injection site is cleaned. A local anesthetic (pain medication) numbs the skin.
- Fluoroscopy (x-ray imaging) may be used to help your doctor see where the medication goes. A contrast “dye” may be added to the medication to help get a better image.
- A local anesthetic is injected near the ganglion to numb the nerves. If the sympathetic nerves are causing your problem, the temperature in your hands or feet will rise quickly. The block will relieve your symptoms for a while. Sympathetic nerve blocks may give long-term relief from symptoms. For this treatment, a few blocks are given 1 to 2 weeks apart.
After the Procedure
You will stay in recovery for about an hour. Once you can walk, you can go home. Have an adult friend or relative drive you. A neck injection may cause the eyelid on that side of your face to droop a little. Your voice may also be hoarse. These things will go away in a few hours when the anesthetic wears off. Within a day or two, your hand or foot symptoms will most likely return. The injection site may also be swollen and sore for a few days. Your doctor can tell you when it’s OK to return to work.
When to Call Your Doctor
Call your doctor if you have trouble breathing or swallowing, prolonged hoarseness, or a fever over 101°F
Risks and Complications
Risks and complications are rare, but can include:
- Bleeding or fluid leakage in the spinal cord
- Puncture of a blood vessel
- Lung puncture (pneumothorax)
The Sympathetic Nerves
The sympathetic nervous system is a network of nerves throughout your body. The nerves branch from the spine. They control some body functions, such as the closing of blood vessels. A problem with these nerves can affect blood flow. Symptoms are often felt in the hands or feet. They may hurt, burn, feel cold or be tender to the touch.
The sympathetic nervous system is controlled by bunches of nerves called ganglions. One large ganglion called the stellate ganglion, helps control nerves in the upper body. In the lower body, nerves are controlled by several ganglions that make up the sympathetic chain.
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