AN EVALUATION OF 2 CONCENTRATIONS OF HYALURONIDASE FOR SUPPLEMENTATION OF PERIBULBAR ANESTHESIA

We studied the effect of the addition of hyaluronidase to a mixture of lignocaine 2% and bupivacaine 0.75% for peribulbar anaesthesia in 60 patients presenting for elective intra-ocular surgery. Using a randomi zed, double-blind design, patients were allocated to one of three grou ps: no hyaluronidase (group A) (n = 20); hyaluronidase 50 iu.ml(-1) (g roup B) (n = 20); hyaluronidase 150 iu.ml(-1) (group C) (n = 20). The speed of onset of the block, the presence of akinesia, analgesia and t he need for supplementary injections were assessed. The addition of 15 0 iu.ml(-1) of hyaluronidase resulted in a mean (SEM) time to akinesia of 9.2 (0.9) min compared to 10.9 (0.9) min in the control group and 10.7 (1.1) min in those receiving the lower dose. Fewer patients in gr oup C required a further injection (20%) than those in groups A (40%) or B (45%). None of the findings were statistically significant. Hyalu ronidase was not associated with any complications.