During the debridement/cleaning phase of wound healing, which factor can impair the process?

• A. Necrotic tissue
• B. Infection
• C. Hypoxia
• D. Excessive scar tissue

Answer: (C)

During the debridement/cleaning phase, the body relies on inflammatory cells such as neutrophils and macrophages to clear dead tissue and hostile organisms. These cells need adequate oxygen to function effectively because their antimicrobial activity depends on the oxidative burst that uses oxygen to kill microbes. When tissue is hypoxic, this respiratory burst is blunted, phagocytosis slows, and debris clearance becomes less efficient. The result is slower cleaning of the wound and a higher chance that bacteria persist, delaying healing. In brief, enough oxygen is essential for immune cells to do the work of debridement; without it, the cleaning phase is impaired.