A Comparison of Immediate Postop Aqueous Cultures in Phaco Patients Receiving Gatifloxacin and Moxifloxacin Preoperatively

Abstract

Abstract: : Purpose: To compare the impact of topical preoperative gatifloxacin and moxifloxacin on immediate postop aqueous cultures in patients undergoing phacoemulsification. Methods: Group I contained 100 patients randomized to receive either gatifloxacin (n=50) or moxifloxacin (n=50) 4 x day for 2 days preop, and 1 drop in the AM before surgery. Group II contained 120 patients randomized to receive either gatifloxacin (n=60) or moxifloxacin (n=60) 4 x day for 2 days preop, and 1 drop in the AM before surgery + 1 drop every 10 min x 4 in the hour prior to surgery. At the completion of surgery, aqueous specimens (0.15cc) were collected with a 30–gauge needle on a TB syringe through peripheral clear cornea and immediately deposited in blood culture media (BBL SeptiChek TSB – Trypticase Soy Broth with SPS and C0₂). Results:No positive aqueous bacterial cultures were obtained for either the gatifloxacin eyes or moxifloxacin eyes for the 100 patients in Group I. Two aqueous cultures (1.6%) were positive in the 120 aqueous specimens in Group II. One positive aqueous culture was observed in an eye that had received gatifloxacin preoperatively, and one aqueous culture was positive in an eye having received moxifloxacin preoperatively. Each positive specimen contained a single staph species. No other bacterial species were detected. The overall rate of positive aqueous cultures in the 220 patients from Groups I and II combined was less than 1% (2/220 = 0.9%). Conclusion:This in vivo study revealed no significant differences in the ability to sterilize the aqueous humor prior to and during phacoemulsification. The positive aqueous culture rate is significantly lower than what has previously been reported in the literature. The reduced positive aqueous culture rate is likely the result of 1) dramatically less aqueous contamination during collection of the specimen secondary to an improved collection technique using a fine needle through the clear cornea, and 2) a real reduction in bacterial exposure to the aqueous during phacoemulsification secondary to the increased efficacy of these two new fourth–generation fluoroquinolones.

Keywords: antibiotics/antifungals/antiparasitics • bacterial disease • aqueous