Effects of levobupivacaine, bupivacaine, and ropivacaine on tail-flick response and motor function in rats following epidural or intrathecal administration1

Abstract

Levobupivacaine, given epidurally or intrathecally, produces longer lasting antinociceptive action than ropivacaine at equivalent concentrations and similar motor blocking effect at lower concentrations in both epidural and intrathecal administrations. Levobupivacaine-induced prolongation of the tail-flick latency is comparable to that of bupivacaine, as is motor blocking effect at higher concentrations. The possibility of significant differential block with levobupivacaine compared with bupivacaine warrants further study.