People use “nerve block” as a catch-all term when, in fact, it can mean different things. Nerve blocks range from pain relief injections to a procedure that can prevent pain from starting.
But what is a nerve block, exactly?
Simply put, a nerve block, or neural blockade, is a way to block the pain messages from certain nerves in your body.
Doctors can use nerve blocks to learn the root of someone’s pain, or to provide relief from chronic pain. Doctors also use nerve blocks as a type of local anesthesia before surgery. For example, an epidural is a type of local nerve block that helps manage the pain of labor in pregnant people.
Nerve blocks can be surgical or nonsurgical. With surgical nerve blocks, doctors cut or destroy a nerve on purpose. Nonsurgical nerve blocks, or nerve block injections, are more common.
What Is a Nerve Block Injection?
A nerve block injection is a targeted way to release medication at or near a particular nerve or group of nerves causing pain. The goal of the injection is to turn off the pain signal.
The needle the doctor uses is like the one you’re used to seeing for flu shots or other vaccinations. Doctors may use imaging to help guide them in placing the needle. This imaging includes:
- Fluoroscope: A device that produces a type of video X-ray.
- Ultrasound: A device that uses sound waves to create an image.
- CT scan: A machine that takes many X-rays to create more detailed images.
Nerve block injections only provide temporary anesthetic or pain relief.
If you’re getting an epidural or nerve block to numb you for surgery, the medication works quickly but wears off soon after surgery. Some nerve block injections for pain work equally as fast, and you should feel the relief right away.
By themselves, nerve blocks usually wear off within hours. But doctors can also inject steroid medications, such as with a nerve root block injection. Steroids take longer to provide pain relief but can last for several months.
Anesthesiologists, radiologists, orthopedic surgeons, and pain management specialists can perform nerve block injections.
How Do Nerve Blocks Help?
Local nerve blocks before surgery can help anesthesiologists better control your pain. Surgeons and patients alike often prefer nerve blocks to general anesthesia because the recovery is quicker. It can mean less time in the hospital and better pain control after your surgery.
As a treatment, nerve block injections help with both chronic (long-term) and acute (short-term) pain. Doctors may suggest nerve blocks to help manage:
- Low back pain, especially sciatic nerve pain.
- Pain related to herniated disks in the back or neck.
- Migraine or other headache pain.
- Facial pain, such as from trigeminal neuralgia.
- Pain related to arthritis.
- Chronic regional pain syndrome.
- Pain related to cancer.
- Pain related to labor and delivery.
- Pain after surgery.
Nerve blocks can also be diagnostic. By targeting certain nerves and seeing if the block improves your pain, doctors can narrow down which nerves are responsible, or if nerves are responsible at all.
Nerve blocks can reduce inflammation, which can help nerves heal. Some people may need several different types of injections to manage long-term pain.
Chemical and Surgical Nerve Blocks
Some people have pain that either doesn’t respond to injections or doesn’t get any better with time. In this case, doctors may use more permanent procedures to block pain signals from nerves.
They may inject chemicals, alcohol, or thermal agents to intentionally damage/freeze the nerve. This is called a neurolytic block.
With a surgical nerve block, the surgeon clamps, removes, or destroys a damaged nerve. Doctors only do this for chronic pain that doesn’t respond to other treatments.
UPMC spine surgeons may do a sympathectomy to clamp off problem nerves (it can be reversed later). A more permanent surgery is a cervical dorsal root rhizotomy. With this, the surgeon uses radiofrequency pulses to destroy nerves related to neck pain.
Preparing for a Nerve Block
For nonsurgical nerve blocks aimed at pain relief, generally, you don’t need to do anything to prepare. (Your doctor will give you any instructions if you do.) Nerve blocks are usually outpatient.
You’ll change into a gown and the doctor will position you on your back, side, or stomach. They’ll clean the skin around the injection site and numb the site. Then, the doctor will inject the needle, with or without image guidance.
You’ll usually rest for a few minutes, to make sure the medication is working and you don’t have any nerve block side effects.
If you’re getting a regional nerve block before surgery, you’ll need to follow the pre-operative instructions your surgeon gives you. If you’re getting an epidural during labor, the anesthesiologist will explain the procedure.
Nerve Block Risks
As with any medical procedure, there are risks with nerve blocks. Bleeding and infection at the injection site are the two biggest nerve block side effects.
Your doctor may accidentally hit the wrong nerve instead of the targeted nerve. Or the medication could unexpectedly spread to other nerves.
Your doctor will review all of the risks with you.
Chronic pain can be debilitating and make everyday activities difficult. Nerve blocks may help along with other treatment and services provided at a UPMC Pain Management clinic.
Sources
Nerve Blocks. Radiologyinfo.org (Radiological Society of North America). Link.