Prediction of levobupivacaine concentrations in neonates and infants following neuraxial rescue blocks.

Total bupivacaine concentrations greater than 2.5 mg L-1 are associated with neurotoxicity in adults. Predicted concentrations after either a repeat spinal or a caudal rescue dose of levobupivacaine 1.5 mg kg-1 1 h after spinal levobupivacaine administration are below the neurotoxic concentration threshold.