Abstract

Background and objective: The axillary brachial plexus block is one of the entry level blocks suitable for novices. Studies about the minimum number of blocks required to achieve competency for neuraxial and epidural anaesthesia exist but data is astray for proficiency in an ultrasound-guided axillary brachial plexus block. The objective of this study was to quantify the number of blocks required by a novice to successfully perform an ultrasound-guided axillary brachial plexus block independently. In addition we aimed to identify the obstacles faced by novice during block performance which leads to its failure or the need for an intervention by an expert.

Methods: The novice trainee was given an introductory training on sono-anatomy of the axillary brachial plexus by an experienced anaesthetist. The trainee was instructed about criteria for failure and success at each procedure along with instruction to use the in-plane technique for axillary brachial plexus block. An ultrasound guided axillary brachial plexus block by multiple injection technique was performed. Whenever the expert anaesthesiologist realised any commitment error by the novice anaesthesiologist which could compromise the patient safety and could cause actual patient harm the procedure was taken over by the expert.

Results: A total of thirty-seven blocks were performed by single novice anaesthesiologist on patients who were scheduled to undergo axillary brachial plexus blocks for orthopaedic or plastic surgery of hand, wrist or forearm. Out of the thirty-seven cases 14 cases were categorized as failure since it required intervention by a supervisor whereas 23 cases were performed by novice independently. The trainee faced number of challenge such as (1) identification of sono-anatomy of brachial plexus at axilla, identification of radial nerve was reviewed to be the most difficult out of all structures with a difficulty of 16% in radial nerve, 10% in musculocutaneous nerve and 8% in both median and ulnar nerve. Other challenges include (2) needle guidance to the nerve, (3) difficulty in drug placement.

Conclusion: Attainment of proficiency in independently performing axillary brachial plexus blocks would require a minimum of 23 supervised blocks with main obstacle being identification of sono-anatomy of axilla.

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