For wound culture collection, which tissue should the swab contact?

• A. Necrotic tissue
• B. Edge skin only
• C. Viable tissue
• D. Air exposure

Answer: (C)

Sampling wound cultures aims to identify bacteria actively involved in the infection, which reside in viable tissue of the wound bed. A swab should be placed on living, perfused tissue at the base of the wound to capture organisms that are actually causing tissue damage and are responsive to antibiotics. Necrotic tissue may harbor bacteria, but they are not representative of the ongoing infection and sampling there can yield misleading results; debridement may be needed first to expose viable tissue. Sampling only edge skin risks collecting surface skin flora rather than the pathogens in the wound, and exposure to air provides no tissue to sample. Thus, the swab should contact viable tissue.