Comparison of lidocaine hydrocarbonate, lidocaine hydrochloride and mepivacaine in the axillary block.

Axillary block was performed on 60 patients undergoing various types of surgical procedures on the upper limb. The patients were divided randomly into three equal groups of 20 and received lidocaine hydrocarbonate 1% or lidocaine hydrochloride 1% or mepivacaine 1%, each solution containing epinephrine 1/400,000. A double-blind design was used. Lidocaine hydrocarbonate and lidocaine hydrochloride were both found to have a shorter latency of analgesia than mepivacaine. Duration of analgesia, quality of the sensory and motor block were not found to be statistically different between the three groups.