How should wound culture be obtained?

• A. Swab old drainage to avoid contamination
• B. Swab into wound bed; aspirate drainage from inner wound; never swab old drainage or skin
• C. Sample from surrounding skin only
• D. Only aspirate drainage

Answer: (B)

When you need a wound culture, the goal is to capture the bacteria that are actively present in the wound tissue and draining fluid, not those on the skin surface or in old drainage. Sampling from the wound bed and extracting drainage from inside the wound provides organisms that reflect the current infection, guiding effective treatment. Swabbing old drainage or surrounding skin tends to pick up skin flora and contaminants, which can mislead results and lead to inappropriate therapy. If there is purulent material inside the wound, aspirating that drainage helps obtain a representative sample from the wound interior. If there isn’t drainage, tissue biopsy or curettage of the wound bed may be needed to get a proper specimen.