Efficacy and safety of 0.5% levobupivacaine versus 0.5% bupivacaine for peribulbar anesthesia

Abstract

Elena Pacella,1 Fernanda Pacella,1 Fabiana Troisi,2 Domenico Dell'Edera,3 Paolo Tuchetti,4 Tommaso Lenzi,1 Saul Collini21Department of Sense Organs, Faculty of Medicine and Dentistry, Rome, 2Department of Medical Surgical Sciences and Translational Medicine Sapienza, Faculty of Medicine and Psychology, Roma, University of Rome, Rome, 3Unit of Cytogenetic and Molecular Genetics, Madonna delle Grazie Hospital, Matera, 4National Institute for Health, Migration and Poverty, Rome, ItalyBackground: This randomized double-blind study examined the use of a new anesthetic agent, levobupivacaine 0.5%, which is the S(−)-enantiomer of a racemic mixture of bupivacaine, for peribulbar anesthesia and compared it with racemic bupivacaine 0.5% alone or in combination with hyaluronidase 10 IU/mL.Methods: A total of 160 patients undergoing ophthalmic surgery were randomized into four groups (n = 40 each) to receive inferotemporal peribulbar injection of levobupivacaine 0.5% (group L), racemic bupivacaine 0.5% (group B), levobupivacaine + hyaluronidase 10 IU/mL (group LH), or racemic bupivacaine + hyaluronidase 10 IU/mL (group BH) by two anesthetists and two ophthalmologists in a ratio of 25% each. Ocular akinesia and orbicularis oculi function were evaluated using a three-point scale; a value < 5 points was considered as requiring surgery, and movements were re-evaluated the day following surgery to confirm regression of the block.Results: The time to onset (12 ± 2.6 minutes versus 13 ± 2.8 minutes) and duration of anesthesia (185 ± 33.2 minutes versus 188 ± 35.7 minutes) were similar between groups L and B. Complete akinesia (score 0) was obtained more frequently when hyaluronidase was used in addition to the anesthetic, with occurrences of 72.5% versus 57.5% in group LH versus L, respectively, and 67.5% versus 45% in group BH versus B. Moderate hypotension (<30% of baseline) was observed in four patients (10%) in group L, two (5.0%) in group B, one (2.5%) in group LH, and three (7.5%) in group BH. The time to onset was significantly different between groups L and BH, B and BH, and LH and BH, and the duration of anesthesia differed significantly between groups B and LH, B and BH, and L and LH. The akinesia score differed significantly between groups L and LH and between groups B and LH (P = 0.043 and P = 0.018, respectively), and the number of patients with a score of 0 differed significantly between groups B and LH and between groups B and BH (P = 0.004 and P = 0.017, respectively).Conclusion: Levobupivacaine is a long-lasting local anesthetic with limited cardiotoxicity and neurotoxicity, and may be considered the landmark for vitreoretinal surgery in elderly patients.Keywords: bupivacaine, levobupivacaine, ophthalmic surgery, peribulbar block, regional anesthesia