Antibacterial properties of EMLA super( registered ) and lidocaine in wound tissue biopsies for culturing

• Published in: Wound repair and regeneration Vol. 14; no. 5; pp. 581 - 585
• Main Authors: Berg, Jais O, Moessner, Belinda K, Skov, Marianne N, Lauridsen, Jorgen, Gottrup, Finn, Kolmos, Hans J
• Format: Journal Article
• Language: English
• Published: 01.09.2006
• Subjects: Escherichia coli; Pseudomonas aeruginosa; Staphylococcus aureus; Streptococcus pyogenes
• ISSN: 1067-1927; 1524-475X
• DOI: 10.1111/j.1743-6109.2006.00157.x

If a tissue biopsy from a chronic wound is sampled for culture, the antibacterial properties of local anesthetics may pose a problem in producing false-negative results. The purpose of this study was to investigate the effects of EMLA super( registered ) (AstraZeneca) and lidocaine on common wound pathogenic bacteria. An in vitro study of a total of 25 clinical isolates and ATCC reference strains of Staphylococcus aureus (including methicillin-resistant S. aureus), Escherichia coli, Pseudomonas aeruginosa, and Streptococcus pyogenes was conducted. The isolates were exposed to the local anesthetic drugs (and some of their contents separately) at 35 degree C over a 24-hour period and time-kill curves were recorded. No culture media were used and saline was used for controls. EMLA super( registered ) was found to have a rapid acting and powerful antibacterial effect and should not be used before culturing tissue samples. Lidocaine 1% was found not to inhibit the bacterial strains when exposure time was held below 2 hours. We conclude that culturing tissue from a wound biopsy is safe within 2 hours when a pure, preservative-free lidocaine 1% solution is used.