Ropivacaine-induced grand mal convulsion after obturator nerve block

We describe a patient to whom ropivacaine 150 mg had been administered during obturator nerve blockade and developed grand mal convulsions because of inadvertent i.v. injection. Venous blood samples were taken 15, 32 and 52 min after the convulsion. The measured total plasma concentrations of ropivacaine were 4.5, 3.5 and 2.9 microg x ml(-1) respectively. The peak plasma concentration at the time of the inadvertent i.v. injection was estimated to be 6.6 microg x ml(-1). The patient recovered uneventfully.