The "Midhumeral" Approach to the Brachial Plexus

Abstract

In Response: We appreciate Frizelle and Moriarty's interest in our article [1] comparing a conventional axillary block and a new approach at the midhumeral level. It is encouraging to observe that they share our enthusiasm regarding this new approach. However, we would like to stress the fact that a comparison between the success rate reported by Lavoie et al. (94%) [2] and ours (54%) is not conceivable. Indeed, Lavoie et al. considered a block to be successful when the dermatomes of the nerves implicated in the surgical site were anesthetized, whereas we required that all dermatomes of the upper extremity be anesthetized. In both studies, the definition of success does not rely on the method used to assess the sensory block, as suggested by Frizelle and Moriarty. In the study of Baranowski et al. [3], there was only a nonsignificant trend toward a positive relationship between the number of nerves located by a nerve stimulator and the success rate. We, as others [4,5], found that the more nerves located, the higher the success rate of the block (87% vs 54%; four versus two nerves located in our study). The reason we compared the midhumeral approach (four stimulations) with the axillary approach (two stimulations) rather than four versus two stimulations in the axillary crease, has already been discussed in the article. Finally, we agree with Frizelle and Moriarty that technical pearls already exist with this new technique [6] and are useful improvements. The technique was named midhumeral because its first description in an American meeting (American Society of Regional Anesthesia, 1996) [7] used this term. We agree, however, that this technique would be better named the brachial or humeral canal approach in future publications. Herve Bouazia, MD Dan Benhamou, MD Department of Anesthesiology; Hopital Antoine Beclere; Clamart Cedex, France