What is the sympathetic nervous system and what is a sympathetic block?
The sympathetic nervous system is half of your body’s unconscious nervous system. The other being the parasympathetic nervous system. The sympathetic nervous system is involved in the body’s “fight or flight” response. It is how your body protects itself in times of stress.
Sometimes the sympathetic nervous system can become dysfunctional due to a disease process or injury. If this dysfunction causes pain it can be termed “sympathetically mediated pain” or sympathetic pain. Some conditions that are implicated in sympathetic pain include Complex Regional Pain Syndrome (CRPS) or by the older term of Reflex Sympathetic Dystrophy (RSD). A sympathetic block can be employed to hopefully blunt this dysfunctional firing of the nervous system. This can hopefully improve pain and improve function.
What are some signs and symptoms of CRPS/RSD?
A patient suffering from CRPS/RSD will most likely have reduced range of motion in the affected extremity due to painful nerves. There might be any combination of the following as well. Swelling, skin color changes, hair/nail loss or fragility, temperature change, the pain might be described as burning, the skin might become hypersensitive.
How is the procedure performed?
Most commonly the sympathetic chain injected is in the neck or lower back. The injection in the neck is near the Stellate (star shaped) Ganglion and can be performed to help with CRPS pain in the upper extremity. In the back it is in the lumbar sympathetic chain that is injected to help with CRPS in the lower extremity. The injection is performed under fluoroscopic assistance in the procedure suite. Xray guidance is needed to ensure accurate placement and to verify that there is no uptake into blood vessels like arteries or veins. The injection is usually performed by injecting local anesthetic into the area where these sympathetic nerves are located. The action of the local anesthetic is to blunt the firing of the nerves that are causing this specific type of nerve pain.
What should I expect after my injection?
The local anesthetic might start helping the day of the injection. Our hope is that the local anesthetic might last for weeks at a time and the injection might need to be repeated as needed to allow pain relief. With the pain relief there should be improved function and the ability to tolerate physical therapy and improved range of motion.
How often should I have the injection repeated?
Injections to help with pain from CRPS might need to be repeated as often as weekly until symptoms improve and function increased. The frequency depends on how you respond to the injection.
Are there things I should look for after having this procedure?
Of course, you can call our office for any question you might have, there are certain “red flag” warnings that you should call us, or if after hours you should go to your nearest ER. These would include severe or worsening pain, fever over 101, new or worsening weakness, injection site redness or drainage.