Persistent cauda equina syndrome with no identifiable facilitating condition after an uneventful single spinal administration of 0.5% hyperbaric bupivacaine.

We diagnosed cauda equina syndrome 15 h after uneventful single spinal administration of 0.5% hyperbaric bupivacaine 12.5 mg through a 27-gauge pencil-point type needle. No preexisting neurologic disorder was recorded. There was no pain or paresthesia during needle placement or drug injection. The sensory levels were bilateral, symmetric, and caudal to T8. Resolution of most of the symptoms occurred within a few days but some foot drop persisted for 2 yr after the procedure. Bupivacaine neurotoxicity is suggested by the absence of any other identifiable cause for this neurologic deficit.