Plasma bupivacaine concentrations following lumbar epidural anaesthesia in children.

Plasma levels of bupivacaine were measured following lumbar epidural administration of 3 mg/kg of 0.5% plain solution in sixteen children. The peak levels were generally between 1.0 and 2 micrograms/ml, the highest being 2.9 micrograms/ml. No manifestations of toxicity were observed. There was a significant positive correlation between peak plasma levels and increasing age.