Comparison of Ultrasound-Guided Axillary Brachial Plexus Block Techniques: Perineural Injection versus Single or Double Perivascular Infiltration

Purpose: We compared three methods of ultrasound-guided axillary brachial plexus block, which were single, and double perivascular (PV) infiltration techniques, and a perineural (PN) injection technique. Materials and Methods: 78 patients of American Society of Anesthesiologists physical status I-II undergoing surgery of the forearm, wrist, or hand were randomly allocated to three groups. 2% lidocaine with epinephrine 5 mu g/mL was used. The PN group (n=26) received injections at the median, ulnar, and radial nerve with 8 mL for each nerve. The PV1 group (n=26) received a single injection of 24 mL at 12-o'clock position of the axillary artery. The PV2 group (n=26) received two injections of 12 mL each at 12-o'clock and 6-o'clock position. For all groups, musculocutaneous nerve was blocked separately. Results: The PN group (391.2 +/- 171.6 sec) had the longest anesthetic procedure duration than PV1 (192.8 +/- 59.0 sec) and PV2 (211.4 +/- 58.6 sec). There were no differences in onset time. The average induction time was longer in PN group (673.4 +/- 149.6 sec) than PV1 (557.6 +/- 194.9 sec) and PV2 (561.5 +/- 129.8 sec). There were no differences in the success rate (89.7% vs. 86.2% vs. 89.7%). Conclusion: The PV injection technique consisting of a single injection in 12-o'clock position above the axillary artery in addition to a musculocutaneous nerve block is equally effective and less time consuming than the PN technique. Therefore, the PV technique is an alternative method that may be used in busy clinics or for difficult cases.