The Science of V.A.C. Therapy
VAC therapy and Macrostrain
The GranuFoam is mainly air so its contracts in response to negative pressure. Contraction of the foam can exaggerate contraction of the wound.
VAC therapy and Microstrain
It has been hypothesized from an in vitro model that tissue deformation stretches individual cells, thereby promoting proliferation in the wound microenvironment. The micromechanical forces may stimulate wound healing by promotion of cell division, angiogenesis and local elaboration of growth factors.
Saxena, V., 2004. Vaccum-assisted closure: microdeformations of wound and cell proliferation. Plastic Reconstructive Surgery. 2004;114:1086-1096
Cellular level
An in vitro wound model compared the cellular response to an open-celled reticulated foam (V.A.C. GranuFoam) under pressure to gauze under pressure. In this model GranuFoam under pressure showed less cell death, greater cell proliferation and migration, and less apoptosis (programmed cell death) than gauze under pressure.
McNulty, A. et al, (2007). Effects of negative pressure wound therapy on fibroblast viability, chemotactic signaling, and proliferation in the provisional wound (fibrin) matrix. Wound Rep. Reg. 2007;1-9