Hyaluronidase as an adjuvant in bupivacaine-lidocaine mixture for retrobulbar/peribulbar block

Hyaluronidase 7.5 IU/mL added to the local anesthetic improves peribulbar block, but smaller concentrations have not been shown to be effective. Ln this prospective, double-blinded study, 714 consecutive ocular surgery patients were randomized into three groups: no hyaluronidase (n = 241), hyaluronidase 3.75 IU/mL (n = 244), and hyaluronidase 7.5 IU/mL (n = 229). Retrobulbar/peribulbar block was performed with two injections of a 1:1 mixture of bupivacaine 0.75% and lidocaine 2%, 6-8 mt. Patient data were collected on demographics, initial volume of local anesthetic, need for supplementary block, and akinesia of the anesthetized eye When hyaluronidase was used (3.75 or 7.5 IU/mL), the initial block was sufficient and the anesthetized eye was akinetic significantly more often than in the group without hyaluronidase. The hyaluronidase groups (3.75 and 7.5 IU/mL) did not differ significantly in any respect. We conclude that the addition of hyaluronidase 3.75 or 7.5 IU/mL improved the success of the initial. retrobulbar/peribulbar block and akinesia and reduced the need for supplementary block.