Neural Complications of Axillary Plexus Block

Abstract

Neural complications following axillary plexus blocks have a reported incidence of less than 2%, while the corresponding figure for supraclavicular plexus blocks varies between 2.2 and 7.5%. This difference may depend on trauma to the nerves during the search for paresthesias, [1,3] which is obligatory in supraclavicular blocks but not in axillary blocks. To test this idea, we studied the incidence of neural complications after axillary blocks performed with or without searching for paresthesias [8] (Table 1). In one group of 290 patients, paresthesias were used to locate the axillary plexus, in the other group of 243 patients, the pulsations of the axillary artery were used to ensure correct placement of the injection needle within the neurovascular sheath. Signs of postblock nerve lesion were found in eight patients (2.8%) in the paresthesia group and in two patients (0.8%) in the nonparesthesia, or artery group, in both of which there were reports of accidental paresthesias during the block procedure. This difference supports the impression that searching for paresthesia may injure nerves and thus increase the risk of postblock nerve lesions.