Negative pressure wound therapy primarily achieves its effects by:

• A. Increasing tissue temperature
• B. Delivering topical antibiotics
• C. Heating tissue
• D. Removing exudate, decreasing edema, and promoting wound healing via controlled suction

Answer: (D)

Negative pressure wound therapy achieves its effects through controlled suction applied to the wound dressing, which actively manages the wound environment. By removing wound exudate, it reduces edema and interstitial fluid pressure, which helps improve microcirculation and oxygen delivery to the wound bed. The suction also produces mechanical forces—macrodeformation and microdeformation of the tissue—that draw wound edges together and stir cellular activity, stimulating fibroblast proliferation, collagen synthesis, and angiogenesis to form healthier granulation tissue. This combination of exudate removal, edema reduction, and mechanically driven tissue stimulation creates favorable conditions for wound healing while protecting the wound from contamination.