title: Effect of lidocaine gel on povidone-iodine antisepsis and microbial survival.
abstract: OBJECTIVE
  To determine whether the use of lidocaine gel prior to povidone-iodine antisepsis is associated with increased microbial survival.
  
  
  METHODS
  Ophthalmology Department, Madigan Army Medical Center, Fort Lewis, Washington, USA.
  
  
  METHODS
  A standardized suspension of Staphylococcus epidermidis was used to inoculate 5 blood agar plates that served as a control. A second group of 5 blood agar plates was inoculated, and then lidocaine gel was applied to the plates. A third group of 5 blood agar plates was inoculated, lidocaine gel was applied, and then povidone-iodine 5% was applied and allowed to cover the plates. A fourth group of 5 blood agar plates was inoculated, and then povidone-iodine 5% was allowed to cover the plates. Cultures of Staphylococcus aureus, Pseudomonas aeruginosa, and Haemophilus influenza were tested in a similar fashion. Microbial growth was evaluated after 24 hours.
  
  
  RESULTS
  The number of colony forming units (CFUs) was similar in the control group and the S epidermidis, S aureus, and P aeruginosa lidocaine only and lidocaine with povidone-iodine groups. In these groups, each plate grew between 200 CFUs and 300 CFUs. In the Haemophilus influenza series, the lidocaine with povidone-iodine group had fewer CFUs than the control group. In all 4 series, the povidone-iodine only group had the least amount of CFUs, ranging from 0 to 6.
  
  
  CONCLUSIONS
  The use of lidocaine gel before application of povidone-iodine 5% resulted in decreased effectiveness of antisepsis and increased microbial survivability. The increase in microbial survivability may increase the risk for postoperative infection in ocular surgery performed under topical anesthesia.
authors.affiliation: Department of Ophthalmology, Madigan Army Medical Center, Tacoma, Washington 98431, USA. john.boden@amedd.army.mil
authors.forename: John H
authors.initials: JH
authors.lastname: Boden
authors.forename: Mary L
authors.initials: ML
authors.lastname: Myers
authors.forename: Thomas
authors.initials: T
authors.lastname: Lee
authors.forename: D Matthew
authors.initials: DM
authors.lastname: Bushley
authors.forename: Mark F
authors.initials: MF
authors.lastname: Torres
mesh_terms: D000779:Anesthetics, Local / Q000494:pharmacology*; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D001419:Bacteria / Q000254:growth & development*; D015169:Colony Count, Microbial; D005782:Gels / Q000494:pharmacology; D006193:Haemophilus influenzae / Q000254:growth & development; D008012:Lidocaine / Q000494:pharmacology*; D011206:Povidone-Iodine / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000235:genetics; D013211:Staphylococcus aureus / Q000254:growth & development; D013212:Staphylococcus epidermidis / Q000254:growth & development
chemical_list: D000779:Anesthetics, Local; D000891:Anti-Infective Agents, Local; D005782:Gels; D011206:Povidone-Iodine; D008012:Lidocaine