Background Topical negative pressure (TNP) therapy has become a useful adjunct in the management of various types of wounds. However, the TNP system still has characteristics of a "black box" with uncertain efficacy for many users. We extensively examined the effectiveness of TNP therapy reported in research studies. Data sources A database search was undertaken, and over 400 peer-reviewed articles related to the use of TNP therapy (animal, human, and in vitro studies) were identified. Conclusions Almost all encountered studies were related to the use of the commercial VAC device (KCI Medical, United States). Mechanisms of action that can be attributed to TNP therapy are an increase in blood flow, the promotion of angiogenesis, a reduction of wound surface area in certain types of wounds, a modulation of the inhibitory contents in wound fluid, and the induction of cell proliferation. Edema reduction and bacterial clearance, mechanisms that were attributed to TNP therapy, were not proven in basic research.

Mechanism of action, Surgical wounds, Topical negative pressure therapy,
The American Journal of Surgery
Erasmus MC: University Medical Center Rotterdam

Mouës, C.M, Heule, F, & Hovius, S.E.R. (2011). A review of topical negative pressure therapy in wound healing: Sufficient evidence?. The American Journal of Surgery (Vol. 201, pp. 544–556). doi:10.1016/j.amjsurg.2010.04.029