Peribulbar anesthesia for intraocular surgery comparison between three anesthetic solutions; evaluating anesthetic efficacy and ocular movements

ABSTRACT

Forty five adult patients, ASA I - III, scheduled for cataract using single medial canthus peribulbar anesthesia were randomly allocated into 3 group, group I received the standard local anesthesia mixture with no hyaluronidase, group II received standard local anesthetic mixture with hyaluronidase 15 IU/ ml and vecronium bromide 1 mg and group III received standard local anesthetic mixture containing hyaluronidase 150 IU/ ml. Patients were assessed for ocular and eyelid movement using Brahma scoring at 1,5 and 10 minutes after injection, on completion of surgery and before the discharge from day surgery unit. If after 5 minutes there was still full movement in any direction or total score of 6 or greater, supplementary anesthesia was applied via inferiolateral route with, 3-5 ml of the test solution. If after 10 minutes, the block was still inadequate, a further infenolateral injection was performed. The need for supplementary anesthesia and total volume of local anesthetic mixture were recorded. There were no statistical differences between the 3 groups as regards the demographic data. The median ocular movement scoring was significantly reduced at 5 minutes in group II and III compared to group I [P <0.05]. No statistical difference in median ocular movement score at 1, 10 minutes and at the end of surgery was found between the groups. Median eyelid movement scoring was reduced significantly at 1 and 5 minutes in group II and III compared to group I [P <0.05]. No statislical difference between the 3 groups found as regards the ocular movement scoring before the discharge from day surgery unit. The number of the patients who received supplementary anesthesia were significantly, reduced in group II and III [5 and 3] compared to group I [8 patients]. The total volume of local anesthetic mixture was significantly lower in group II and III compared to group I [P < 0.05]. There was no difference between the 3 groups as regards the visual acuity at the start of surgery or before discharge. We concluded from the study that the addition of neuromuscular blocking agent vecronium bromide 1 mg to standard local anesthetic mixture with hyaluronidase 15 IU/ ml as recommended by British National Formulary improved global akinesia and operative condition with no side effects and without too much increase in the concentration of hyaluronidase in adult patients undergoing cataract surgery using single medial canthus peribulbar anesthesia