Treatment of surgical sutures with antiseptic or antibiotic to reduce suture contamination in strabismus surgery: an in vitro experiment

摘要

Purpose: Bacterial contamination of suture material has been reported following strabismus surgery even with current standard prevention techniques of surgical field sterilization and disinfection with povidone iodine. Pretreatment of these sutures with antiseptic or antibiotics may reduce the bacterial load and theoretically further reduce incidence of endophthalmitis following strabismus surgery. The purpose of this study is to determine if treatment of sutures used in strabismus surgery with antibiotic or antiseptic can significantly reduce suture contamination. Methods: This was an in vitro experiment designed to compare suture contamination following exposure to stock solutions of bacteria. Sutures (6-0 polyglactin) were divided in four groups: untreated (control) group 1, povidone iodine treated group 2, gentamicin 2.5% solution treated group 3, and gentamicin ophthalmic ointment treated group 4. Treated sutures were soaked in the antibiotic or antiseptic for 5 minutes. Suture from each group was exposed to a bacterial solution of 5.0 log concentration of four types of bacteria (S. pneumoniae, S. aureus, S. epidermidis, and H. influenzae), sonicated, and cultured on blood agar and chocolate agar plates. Growth at 24 hours was measured in colony forming units. Results: The untreated control, gentamicin 2.5% solution treated, and gentamicin ophthalmic ointment treated groups had growth after exposure to each of the four bacterial solutions. The povidone iodine 10% treated group did not demonstrate any growth which was found to be statistically significantly different (p0.0001). As analyzed by the Kruskal-Wallis Exact Test, the relative growth among the other treatment groups was not found to be statistically significant (p=0.8432). Conclusions: Contamination of suture during strabismus surgery has been reported and is the suspected mechanism of infection for post-operative endophthalmitis following strabismus surgery. Lack of bacterial growth from the povidone iodine treated suture group is an important finding because this suggests pretreating sutures with antiseptic will decrease suture contamination and theoretically rates of infectious endophthalmitis following strabismus surgery.