[Comparison of the effect and serum level of mepivacaine HCL and mepivacaine CO2 in axillary brachial plexus anesthesia].

The latency period and spread of axillary plexus block using 40 ml mepivacaine carbonate (1% solution) or mepivacaine hydrochloride was studied in thirty patients scheduled for surgery of the hand-forearm region. The sensory block of the nervus axillaris, musculocutaneus, radialis, medianus, ulnaris and cutaneus brachii medialis was recorded using the pin prick test every 4 min after injection and the motor block was assessed by testing the strength of the corresponding muscles. The only significant difference between the two local anaesthetic solutions was a few more frequent and faster anaesthesia of the nervus musculocutaneus after 16, 20 and 24 min. A comparison between the serum levels of the first five patients of each group showed a faster increase and a higher level after the injection of carbonated mepivacaine. Carbonated mepivacaine doesn't have any practical advantage for axillary plexus block.