Povidone-iodine before lidocaine gel anesthesia achieves surface antisepsis

Viscous lidocaine interferes with ocular surface antisepsis. The current study was designed to evaluate the impact on surface antisepsis of different application sequences with lidocaine gel and povidone-iodine solution.

Blood agar plates inoculated with Staphylococcus epidermidis were treated with varying sequences of 2% lidocaine gel and 5% povidone-iodine solution. The plates were then incubated at 37°C for 24 hours and bacterial growth was determined.

Plates on which povidone-iodine was applied alone or prior to lidocaine gel demonstrated no bacterial growth regardless of whether the antiseptic was retained on the plate for 5 seconds or for 30 seconds. There was no statistically significant difference between bacterial growth on plates not treated with povidone-iodine and on plates treated with lidocaine gel alone or prior to povidone-iodine (P = .553 and P = .485, respectively).

Povidone-iodine effectively reduces bacterial counts when applied alone or prior to lidocaine gel. Lidocaine gel was confirmed to be a barrier to antisepsis when administered prior to povidone-iodine.