Theoretical and Pre-Clinical Models of Vacuum Assisted Closure

Vacuum Assisted Closure (VAC) has changed how physicians treat complex and chronic wounds. For over 20 years, we have studied the mechanism of action of these devices in both an academic based research laboratory and in an industry-based laboratory.We performed a literature review of the theoretical and pre-clinical published studies from the two labs which related to the biomechanics of open pore reticulated polyurethane interfaces.The VAC device applies a direct mechanical interface to the wound surface. The interaction of the foam under suction with the wound surface causes surface deformation and cell stretch. The suction removes fluid from the tissues. There are increases in angiogenesis with better vessel morphology than standard dressings. The effect is dependent on the pore size of the foam, the pressure of application and the waveform of application. Undoubtedly, patient factors such as age, diabetes and radiation affect the response.Pre-clinical studies can help in the design and optimization of mechanical-based wound healing devices. Current work on the effects of these devices on lymphatics and scarring are areas of active investigation.