Electron microscopic examination of needles used in infraclavicular brachial plexus block

Abstract

Aim: The application of peripheral block is frequently used in anesthesia practice. One of the most significant complications of this procedure is peripheral nerve damage that can develop due to the needles used. The aim of this study was to determine the presence of tissue residue on the needle and to obtain information about damage to surrounding tissues during this procedure by examining the needles used in brachial plexus block with electron microscopy. Methods: This prospective-cohort study included patients who were to undergo forearm or hand surgery in the Orthopedics Clinic under anesthesia with infraclavicular brachial plexus block performed with 2 different techniques: The local anesthetic agent was administered to the subclavian artery at 6 and 9 o’clock levels in Group 1 and 2, 6 and 9 o’clock levels in Group 2. The needles used during the block were preserved in glutaraldehyde solution then examined with electron microscopy. The presence of tissue on the needles was recorded and statistical evaluations were made. Results: The needles used in two different techniques of infraclavicular brachial plexus block were examined under scanning electron microscope. The amount of tissue residue remaining on the needle in Group 1 was significantly less than that in Group 2 (P<0.001). Conclusion: When it is considered that ultrasound provides a 2-dimensional image, the fewer the number of needle manipulations made during the procedure of brachial plexus block application, the less damage will be made to the surrounding tissues, thus reducing the possibility of mechanical nerve damage.