Individualizing the use of negative pressure wound therapy for optimal wound healing: a focused review of the literature.

Currently available research suggests that negative pressure wound therapy (NPWT) creates a moist wound healing environment, drains exudate, reduces tissue edema, contracts the wound edges, mechanically stimulates the wound bed, and influences blood perfusion at the wound edge, which may lead to angiogenesis and the formation of granulation tissue. Although no clear evidence is available that NPWT accelerates wound healing compared to other interventions or that one form of NPWT is better than another, preclinical research suggests that the most commonly used dressings, level of negative pressure, and application mode (continuous, intermittent, or variable) may not be optimal for all patients. To summarize available literature related to these NPWT choices, pertinent literature published between 2005 and 2010 was reviewed. Preclinical study results suggest that the maximal biological effect of NPWT at the wound edge often can be achieved at -80 mm Hg and that foam dressings may be advantageous for large defect wounds, whereas gauze dressings may be more suitable for smaller wounds or when scar formation or pain is a concern. Preclinical research results also suggest that intermittent or variable pressure application has a better effect on granulation tissue formation than continuous application. The variable pressure mode maintains a negative pressure environment at lower pressure settings without dramatic fluctuations inherent to intermittent (on-and-off) pressure. Prospective, controlled clinical studies are needed to compare NPWT to other advanced wound care protocols of care and to ascertain the effect of various NPWT methods and regimens on outcomes of care.