What is a local anesthetic nerve block and when is it helpful?
A local nerve block both diagnoses and controls pain associated with a group of specific nerves. Pain relief from a local anesthetic can restore your quality of life, but they are often short-lived and must be repeated or followed by a long-acting nerve block (called a denervation).
Sometimes, these nerves supply an abdominal or pelvic organ or are special nerves called sympathetic/visceral nerves. In those cases, a nerve block can be used as a diagnostic procedure to verify if an organ is the source of pain. We begin the procedure by performing test block using a local anesthetic. If you achieve good pain relief from the local anesthetic, then we may freeze or inject a nerve block using alcohol or phenol for a denervation procedure providing long-lasting pain relief. By injecting these nerves with alcohol or phenol, the procedure interrupts pain signals for 6-12 months. When the effect wears off, the same treatment can be repeated. Nerve blocks with phenol or alcohol carry more risk of complications than local anesthetic blocks. Before any procedure, we will discuss these risks with you.
Nerve blocks may be used to:
- Determine the source of pain
- Control acute pain
- Avoid surgery
- Provide short-term pain relief after some surgeries and other procedures
- Treat chronic pain when other treatments fail or cause side effects
- Predict how pain will respond to other long-term treatments
What happens during a nerve block?
We will first start an IV so that we can administer some medication to relax you and relieve any discomfort. When using ultrasound guidance, we typically employ a simple local anesthetic at the skin. We then scrub your back with a cleaning solution while you lie positioned so that we can clearly visualize the nerve or areas where the nerves reside. We will numb a small area of skin and use ultrasound and X-ray guidance to locate the nerve and place the needle. Once we are sure that the needle is in the correct location, we will inject a medication along one or more nerves.
What happens after a nerve block?
You will rest in the recovery area for 30-60 minutes before you are discharged to go home. Your back may feel numb or weak for a few hours, but this is normal. You should start feeling some relief in about 24-72 hours but it may take 2-3 weeks in some cases.
For your own safety, you cannot drive the day of the procedure, so please plan to have someone drive you to and from your appointment. The day after the procedure, you may resume normal activities and work.