A Comparison of a Triple-Injection Axillary Brachial Plexus Block With the Humeral Approach

Background and Objectives: This prospective, randomized, and single-blind study compared effectiveness, performance, onset, and total anesthetic time and complications of the multiple axillary block (median, radial, and musculocutaneous nerves) with the humeral approach. Methods: One hundred patients were randomly assigned to 2 groups. In group A (axillary) median, radial, and musculocutaneus nerves were located by a nerve stimulator and injections were made. In group H (humeral) all 4 terminal nerves of the brachial plexus were located and injections were made. A total of 40 mL mepivacaine of 1% was used. Results: Complete sensory block of all 6 peripheral nerves occurred in 94% and 79% of patients in groups A and H, respectively (P < .05). The time to perform the block was shorter in group A (8 ± 4 minutes v 11 ± 4 minutes; P < .001); onset time was shorter in group A (16 ± 8 minutes v 21 ± 9 minutes; P < .05); total anesthetic time was shorter in group A (24 ± 8 minutes v 33 ± 10 minutes; P < .0001). Complete motor block was greater in group A (88% v 66%; P < .05). More vascular punctures occurred in group A (22% v 8%, P < .05). Conclusion: The triple-injection axillary block was more effective than the humeral approach as it was associated with more cases of sensory and complete motor block and gave shorter performance and onset times.