Lumbar Sympathetic Nerve Block
A lumbar sympathetic nerve block is administered to both diagnose and treat pain in the lumbar (lower) region of the spine. It is used to determine whether the lumbar sympathetic nerves, which carry pain impulses from the lower extremities, are the cause of the pain, and, in some cases, serves to eliminate that pain altogether. During the procedure, medication is injected into or around the lumbar sympathetic nerves on one side of the body.
Underlying conditions for which a lumbar sympathetic block may be considered include the following:
- Complex regional pain syndrome
- Herpes zoster (shingles)
- Peripheral vascular disease
When successful, the injections reduce pain, inflammation, abnormal skin color and sweating, and improve the patient‘s mobility.
Lumbar Sympathetic Nerve Block Procedure
Receiving a lumbar sympathetic nerve block injection takes only a few minutes, although the patient will likely spend a few hours in an outpatient surgical setting or doctor‘s office. These hours include the time needed for preparation, positioning and recovery. During the procedure, the patient lies facedown, and a local anesthetic is administered. In most cases, patients are also sedated to minimize anxiety. Once the local anesthetic has numbed the skin, the injection is administered.
The injection contains an anesthetic to numb the inflamed area. Sometimes it also contains a corticosteroid to reduce inflammation, or clonidine, a hypotensive agent. These medications are added to provide long-lasting pain relief. Immediately after receiving an injection, a patient may experience warmth in the leg, but the sensation disappears quickly.
Risks of a Lumbar Sympathetic Nerve Block
Although receiving a lumbar sympathetic nerve block is a safe, there is a risk of complications, which includes infection at the injection site, nerve damage, bleeding, or leakage of spinal fluid.
Recovery from a Lumbar Sympathetic Nerve Block
After a lumbar sympathetic nerve block procedure, a patient usually returns home after a few hours, and is able to return to work the next day. The effectiveness of a lumbar sympathetic nerve block varies. Some patients experience permanent relief, whereas others experience relief for only a few weeks or months, and require additional treatment.
If the block relieves the patient‘s pain, a series of injections may be administered to provide long-lasting relief. If the block does not relieve pain, radiofrequency ablation may be considered.
Sympathetic Nerve Block
The sympathetic nervous system is responsible for regulating involuntary body functions, including blood flow, heart rate, digestion and perspiration. Sympathetic nerves spread outward from the spine, and, when compromised, can cause pain in various parts of the body. A sympathetic-nerve block is an injection of medication into whichever of these nerves is causing the pain. It works by numbing the nerve, which interrupts the pain signals the nerve is sending to the brain. It is used both to diagnose damage of and treat pain caused by the sympathetic nerves.
Uses for Sympathetic-Nerve Blocks
There are a number of uses for sympathetic nerve blocks; two of the most common are therapeutic and diagnostic. A therapeutic nerve block is used to treat pain; it typically contains a local anesthetic. Nerve blocks used to treat chronic pain can work for up to 6 to 12 months, and can be repeated as needed.
A diagnostic nerve block is designed to determine the cause of pain; an anesthetic is injected only for the amount of time it takes to pinpoint the area causing the issue.
Sympathetic-Nerve-Block Treatment Areas
Injections of sympathetic nerve blocks are given near various areas of the spine. Types of blocks include stellate blocks, which target the upper spine‘s sympathetic nerves, including those that run to the chest, arms, neck and head; lumbar blocks, which target the lower spine‘s sympathetic nerves, including those that run to the legs and feet; and thoracic-region blocks, which target the mid-spine‘s sympathetic nerves, including those that run to the abdomen.