Comparison of levobupivacaine 0.5% or bupivacaine 0.5% both in a mixture with lidocaine 2% for superficial extraconal blockade

Abstract

Purpose:To evaluate the quality and efficacy of Peribulbar blockade for superficial extraconal anesthesia with levobupivacaine 0.5% versus bupivacaine 0.5%, both combined with lidocaine 2% for patients undergoing phacoemulsification.Materials and Methods:In this prospective, double blind study, 150 patients were randomly divided into two groups: group-1 received a Peribulbar block (PB) with a mixture of evobupivacaine 0.5% and lidocaine 2% while group-2 received a PB with a mixture of bupivacaine 0.5% and lidocaine 2%. The block was performed by insertion of a short needle (15 mm) in infra-temporal space just above inferior orbital notch. An initial volume of 6 9 ml of either mixture was injected until total upper eyelid drop. Akinesia score was assessed at 2, 5, and 10 min after the block. The degree of pain was assessed by a verbal rating scale immediately after block, at the end of surgery and 4 h postoperatively. The patients and surgeons were asked to rate their satisfaction level of the quality of block postoperatively. Data were analyzed with the unpaired, two-tailed t-test and the Chi-square test as appropriate. P < 0.05 was considered statistically significant.Results:There were no significant differences between groups with respect to the akinesia score (P = 0.2) at 2, 5, and 10 min, the number of supplementary injections (P = 0.84) and initial and total required volume of local anesthetics (P = 0.80 and 0.81, respectively). There was no significant difference between the groups regarding surgeon and patient satisfaction (P = 0.53 and P = 0.74, respectively). Similarly the verbal rating scales assessed at three different occasions were not significantly different between the groups (P > 0.05 all cases). The need for additional intra-operative topical anesthetic was also similar between the groups. (P = 0.69).Conclusions:Superficial extra-conal block with a mixture of levobupivicaine 0.5% and lidocaine 2% or bupivicaine 0.5% and lidocaine 2% provides similar block quality and efficacy.