Often, a group of nerves – called a plexus or ganglion – causes pain to an area of the body. This pain can be “turned off” by using a specific injection that blocks the pain signal from reaching the brain. This is called a nerve block.
Nerve blocks are injections used to treat chronic pain when ineffective medications or other treatments cause negative side effects. They allow a damaged nerve proper time to heal, provide temporary pain relief, and can be used to identify a specific cause of pain. Oftentimes, your physician will perform a test block with a local anesthetic. If you have positive results and pain relief from the test block, your doctor will move forward with an injectable nerve block.
Why are Nerve Block Injections Used?
Nerve blocks are used for a variety of purposes. Patients with acute or chronic pain may receive a nerve block injection for temporary pain relief. Since pain is such an individual experience, nerve blocks are also used to help physicians diagnose the source of pain by measuring the patient’s response to the injection. This helps determine a treatment plan.
Other purposes for nerve blocks are:
- To predict the outcome of any given treatment. Prognostic nerve blocks are performed to determine if a more permanent treatment (surgery) would be more successful in treating pain.
- To avoid surgery, in some cases.
- To prevent additional pain from a procedure or surgery that can cause negative side effects, such as phantom limb pain.
Types of Nerve Blocks
Since nerve blocks can be used for various purposes to help reduce, treat, and prevent pain, it is no surprise that there are many different types of nerve blocks.
The benefit of nerve blocks is that they can be used in almost every body area to treat pain. Because of this, there are different nerve block types. No area of pain should be treated equally. Here are few types of nerve blocks that are available:
- Therapeutic nerve block contains a local anesthetic to control acute pain.
- Prognostic nerve blocks: These are used to help your physician predict the effectiveness and outcome of a given treatment.
- Diagnostic nerve block: This block contains an anesthetic that helps relieve pain and helps pain specialists determine the root cause of chronic or acute pain.
- Sympathetic nerve block: This type of block is used to determine if there is any type of damage or injury to the sympathetic nerve chain – the network of nerves that extends the length of the spine.
- Preemptive nerve blocks: These types are meant to prevent pain after a surgery that can cause issues like phantom limb pain.
How are Nerve Blocks Performed?
Nerve block injections use imaging guidance – such as fluoroscopy or CT scans – to guide the needle into the injection site. This allows the physician to place the needle in the most accurate location for the injection to be most beneficial. Depending on the patient’s needs, the syringe will be filled with medication.
A small needle will be inserted through the skin and directed towards the injection site. A small amount of contrast material may be used to confirm needle placement in the appropriate location. The injection itself will be administered with a syringe much like one used for a routine vaccination. The doctor will fill the syringe from a small vial of medication. The type of medication used depends on individual patient needs.
This is typically performed as an outpatient procedure and only take a few minutes to administer.
Your physician will position you on the table or surface to allow access to the site to be injected. Using imaging guidance, the doctor will identify where the needle needs to be placed. In some cases, more than one injection may be required, depending on the area of pain that needs to be covered. The medication will go into effect quickly, but the doctor will have you stay in the office to ensure no immediate and unexpected side effects.
Side Effects and Risks of Nerve Blocks
Nerve blocks are safe; however, like any procedure and injection, risk is always involved. Typically, nerve blocks carry fewer side effects than other types of medication.
Some side effects include:
- Injection site soreness and tenderness
- Damage to nerves
- Elevated blood sugar
- Horner’s syndrome
Nerve blocks provide temporary relief from pain and the results can vary from patient to patient. Speak to your doctor about your options for relieving your pain so you can determine a course of action. Nerve blocks are among various anesthetics used to treat pain caused by a group of nerves.