Peribulbar block for cataract surgery: a prospective double-blind study of two local anesthetics.

We carried out a prospective double-blind study to compare the effectiveness of 2% lidocaine hydrocarbonate (54 patients) and 2% lidocaine hydrochloride plus 0.5% bupivacaine hydrochloride (46 patients) in achieving peribulbar block of the orbit in patients undergoing cataract surgery. A total of 150 IU of hyaluronidase was added to each syringe before injection. Anesthesia was done with a total of 6 mL injected into the periphery of the orbit and a further 3 to 4 mL injected for seventh cranial nerve block. A successful block, defined as akinesis of the globe at 4 minutes after injection, was achieved in 94% of the patients, with no difference between the two groups. Two minor complications (transient lateral rectus paresis and a small retrobulbar hematoma) were observed. We recommend this method of peribulbar block as it has a rapid onset and its use may lead to a reduced occurrence of the central nervous system complications associated with retrobulbar block.