Clinical efficacy and pharmacokinetics of 1% ropivacaine and 0.75% bupivacaine in peribulbar anaesthesia for cataract surgery

Peribulbar anaesthesia with 1% ropivacaine and 0.75% bupivacaine, both with hyaluronidase, was assessed in a prospective, randomised, double-blind stu dy of 100 patients undergoing cataract surgery Pharmacokinetic data were ob tained from 22 subjects. Akinesia of the globe developed slightly more rapi dly in the ropivacaine group, but this difference was only statistically si gnificant at 2 min after injection of the local anaesthetic. Lid akinesia w as significantly more complete ill the ropivacaine group. There were Ilo di fferences between the groups with respect to peri-operative analgesia or du ration of akinesia. The dose-adjusted maximum concentration of ropivacaine was approximately twice that of bupivacaine with significantly higher value s of the area under the concentration-time curves. No drug-related adverse effects were observed. We conclude that there are no clinically significant differences in the quality of the sensory and motor block between 1% ropiv acaine and 0.75% bupivacaine when used for peribulbar anaesthesia.