Evaluation of Brachial Plexus Nerve Variations in Axilla by Ultrasonography.

PURPOSE: The use of ultrasound in peripheral blocks has now become the gold standard. Ultrasound is a method that is easy to apply and most importantly does not carry any risk, and its only disadvantage is based on the skill and knowledge of the practitioner. Injury to vascular structures, which is the most common occurrence in peripheral block applications, has been significantly reduced by the use of ultrasound. The aim of this study is to determine the location of nerve branches and to determine the most common anthropometric parameters in the axillary fossa. In this way, the common anatomy of the axillary BP will be determined and will guide the practitioners while performing the axillary plexus block.

DESIGN: Observational Clinical Study.

METHODS: The patients were positioned with forearm abducted 90 degrees and elbow flexed 90 degrees. Using a high-frequency linear ultrasound probe, it was placed on the lateral border of the pectoralis major muscle in the transverse plane. Pulsation of the axillary artery was visualized and shifted slowly to view the nerves around the artery. The axillary vein was also visualized to facilitate the movement of the transducer and to find the nerve localization more easily. The regions on the prepared wheel were marked. At the same time, demographic information such as gender, age, weight, and height of the patients were also recorded.

FINDINGS: 248 patients, 61.3% female and 38.7% male. Our results showed that only 59% were compatible with the most common nerve locations in cadaveric dissections and the locations described in anatomy textbooks.

CONCLUSIONS: Since there are many anatomical variations, validation of nerves with a nerve stimulator as well as simultaneous visual application under ultrasound guidance will increase the success chance of axillary brachial plexus block and protect it from unwanted complications.