Topic Overview

Peripheral nerve blocks are a type of regional anesthesia. The anesthetic is injected near a specific nerve or bundle of nerves to block sensations of pain from a specific area of the body.

Nerve blocks usually last longer than local anesthesia. They are most commonly used for surgery on the arms and hands, the legs and feet, or the face.

Positioning of the needle during a nerve block may result in touching the nerve to be blocked with the tip of the needle. When this occurs, you may experience a sharp sensation like an electrical shock in the part of the body supplied by the nerve. Be sure to let your anesthesiologist know if you feel such a sensation.

Other medicines are often given with nerve blocks to make you relaxed or sleepy (sedatives) or to reduce pain. These are usually given as a pill or through a vein (intravenously, IV).

People are carefully watched during the procedure, because the anesthetics used for regional nerve blocks may affect the central nervous system, cardiovascular system, and respiratory system (airway and lungs) and may affect blood pressure, breathing, heartbeat, and other vital functions.

Nerve blocks may be most useful when the procedure:

• Can be confined to a specific region of the body that can be anesthetized with a nerve block.
• Involves large surface areas of the body where injection with a large volume of local anesthetic might cause side effects that affect the whole body.
• Involves an area of the body where injection of a local anesthetic would cause distortions that might cause problems with the surgery, such as the face.
• Can be done in a relatively short time. Nerve blocks may not last long enough for some procedures.