Evaluation of periocular pathogens in ophthalmic surgery

Purpose. A three-part study was performed to evaluate commonly used "non-sterile" peri-operative supplies, using laboratory culture techniques. Methods. Part one: Povidone-Iodine 5% (Betadine) scrubs were performed on 8 patients undergoing cataract extraction. Each patient had three eyelashes harvested pre- and post-operatively. These eyelashes were cultured. Part two: Five rolls of non-sterile adhesive tape (Transpore, 3M) were left in an operating room for one week. The adhesive and non-adhesive sides from each roll were cultured. Part three: Five sterile eye pads were removed from their packaging using sterile technique and cultured. All specimens were cultured on blood and chocolate agar plates and thioglycolate broth. Results. Four of eight patients had growth of microorganisms at 48 hours from eyelashes removed before the Betadine prep. Only one of eight patients was culture positive at 48 hours from eyelashes removed after the Betadine prep. This patient was culture negative prior to the scrub. Only one of six adhesive-side tape cultures had no growth. Four of five non-adhesive side tape cultures had growth of microorganisms including Staphylococcus, Bacillus, and other species. The five sterile pads had no growth. Conclusion. Betadine effectively decreases periocular microbial flora. Our study shows, however, that the application of adhesive tape to the eyelid may introduce pathogens into a culture-negative environment.