[Peridural anesthesia with bupivacaine-CO2 and bupivacaine-HCl. A comparative study].

Carbonated bupivacaine and bupivacaine hydrochloride were used for epidural anaesthesia in patients undergoing surgery of the lower extremities. Thirty patients received 20 ml 0.5% bupivacaine hydrochloride and 32 patients 20 ml 0.42% carbonated bupivacaine. Carbonated bupivacaine had a more rapid onset of action and spread of both sensory and motor blockade than its hydrochloride salt. The differences were statistically significant.