Purpose: To determine the efficacy of reducing conjunctival bacterial flora with topical ofloxacin when given for 3 days compared with 1 hour before surgery.
Design: Prospective, randomized, controlled trial.
Participants: Ninety-two eyes from 89 patients were randomized to a control group (48 eyes) or study group (44 eyes).
Methods: All patients from both groups received topical ofloxacin 0.3% 1 hour before surgery and a 5% povidone iodine scrub of the periorbital area before surgery. The patients in the study group received additional ofloxacin four times daily for 3 days before surgery.
Main outcome measures: Conjunctival cultures were obtained at five separate time points and were inoculated in solid and liquid culture media. The presence of bacteria was determined, quantified, and identified.
Results: Forty-two percent of eyes in the control group had positive conjunctival culture immediately before surgery, compared with 19% of eyes in the study group (P < 0.05). Immediately after surgery, 34% and 14% of eyes had positive cultures in the control and study groups, respectively (P < 0.05). Quantitatively, fewer bacteria were isolated from eyes in the study group compared with those in the control group for culture samples that were obtained both before povidone iodine scrub and at the conclusion of surgery (P </= 0.05).
Conclusions: The application of topical ofloxacin for 3 days before surgery appears to be more effective in eliminating bacteria from the conjunctiva than an application of ofloxacin 1 hour before surgery.