Abstract

An increasing number of patients undergoing surgery or with acute or chronic pain receive nerve blocks for analgesia currently. The continued popularity of regional anesthesia will depend upon a high success rate of the blocks. The peripheral nerve stimulator (PNS) can aid in achieving this success rate. This review article describes the electrophysiology of peripheral nerve stimulation, desirable characteristics of nerve stimulators, efficacy of presently available nerve stimulators and sheathed and unsheathed needles. Furthermore, success with the use of the nerve stimulator requires sound knowledge of anatomy of the region to be blocked and innervation of the muscle groups involved in addition to learning the correct techniques of peripheral nerve stimulation. Failure of nerve blocks using PNS is usually due to incorrect techniques of nerve stimulation.