Axillary block by "selective" injections at the nerves involved in surgery using a peripheral nerve stimulator: a comparison with a "standard" triple-injection technique.

Background and Objectives: A triple-injection technique (injections at the median, musculocutaneous, and radial nerves) for axillary block affords a high incidence of complete block (all the nerves below the elbow). However, in certain surgeries, only 1 or 2 nerves are involved in the surgical field. The aim of this prospective randomized study was to test the effectiveness of surgical anesthesia of a "selective" approach in which only the nerves involved in surgery were electrically located and injected. Methods: Three types of surgery were selected. Type 1 included surgery on the fifth finger, type 2 included superficial surgery (without bone involvement) on the palm or on the dorsum of the hand, and type 3 included any surgery on the first 3 fingers. For each type, 138 patients were enrolled and divided into 2 groups: group SEL in which only the nerves involved in the surgical field (1 or 2) were located and injected and group TNS in which a standard triple-nerve stimulation technique was used. Results: A lower rate of surgical anesthesia (84% vs 92%; P Conclusions: A standard triple-nerve stimulation technique seems to be preferable to the selective approach even when a limited number of nerves are involved in the surgical field.