Comparison of l-bupivacaine 0.75% and lidocaine 2% with bupivacaine 0.75% and lidocaine 2% for peribulbar anaesthesia

Abstract

L-Bupivacaine has a safer side-effect profile than bupivacaine. We compared the efficacy of a mixture of L-bupivacaine 0.75% and lidocaine 2% with bupivacaine 0.75% and lidocaine 2% for peribulbar anaesthesia in cataract surgery. Ninety patients were allocated randomly to receive 8 ml of a mixture of equal parts of bupivacaine 0.75% and lidocaine 2% or an equal volume of L-bupivacaine and lidocaine 2%. Hyaluronidase 15 IU ml(-1) was added to both solutions. There were significant differences between the groups in clinical end-points. The median time at which the block was adequate to start surgery was 4 min (interquartile range 4-8 min) in the bupivacaine group and 8 min (5-12 min) in the L-bupivacaine group (P=0.002). Median ocular and eyelid movement scores were similarly significantly decreased in the bupivacaine group compared with the L-bupivacaine group at all times (P</=0.03). There was no difference between groups in the incidence of minor complications. A mixture of bupivacaine 0.75% and lidocaine 2% provides faster onset time than a mixture of L-bupivacaine 0.75% and lidocaine 2%.