Overview

A peripheral nerve block is a shot of numbing medicine near a specific nerve or group of nerves. It can be used to numb a part of the body (often an arm or a leg) for a procedure. It may also help control pain after the procedure.

Types of nerve blocks

Some common types of peripheral nerve blocks include:

• Femoral nerve block. It's done with an injection into the groin area to numb the femoral nerve. It numbs most of the leg.
• Popliteal nerve block. It's done with an injection into the back of the knee to numb the sciatic nerve. It numbs most of the lower leg and foot.
• Brachial plexus block. It's done with an injection into a group of nerves (called the brachial plexus) between the spine and shoulder. The shot is usually given in the neck or just above the collarbone. It numbs the shoulder, arm, and hand.

How it's done

The doctor may use ultrasound or another method to help guide the needle that will be used for the nerve block.

After finding the right spot, the doctor uses a tiny needle to numb the skin. Then the doctor puts the nerve block needle into the numbed area and injects numbing medicine near the nerves. If you are awake, you may feel some pressure. But you should not feel pain.

The nerve block is often used with general anesthesia or with medicine that makes you feel relaxed or sleepy during the procedure. Or the nerve block may be all that's needed. In that case, you can stay awake without feeling pain.

How to prepare

You will get a list of instructions to help you prepare. Your anesthesia specialist will let you know what to expect when you get to the hospital, during the surgery, and after.

You'll be told when to stop eating and drinking.

If you take medicine, you'll be told what you can and can't take before surgery.

You'll be asked to sign a consent form. The form says that you know the risks of anesthesia. Before you sign, your specialist will talk with you. You'll discuss the best type for you. And you'll learn the risks and benefits of that type.

Many people are nervous before they have surgery. Ask your doctor about ways to relax before surgery.

What to tell your doctor

Tell the specialist about any health problems (such as sleep apnea). Also talk about any past surgeries and if a family member had problems with anesthesia. Let them know if you're pregnant or if you smoke, drink alcohol, or use drugs. Give them a list of all medicines, vitamins, and herbal products you take.

Risks

Problems after a nerve block are not common. There is a small risk of nerve damage, infection, or bleeding. In rare cases, the medicines used can cause more serious problems, such as heart and breathing problems.