Vacuum-assisted closure: A new method for wound control and treatment: Animal studies and basic foundation

A series of basic animal studies using a new subatmospheric pressure technique (The V.A.C.) to expedite wound healing are presented. The technique entails placing an open-cell foam into the wound, sealing the site with an adhesive drape, and applying subatmospheric pressure (125 mmHg below ambient) that is transmitted to the wound in a controlled manner. Utilizing a pig model, four studies were undertaken to determine the effect of subatmospheric pressure on laser Doppler-measured blood flow in the wound and adjacent tissue (N = 5), rate of granulation tissue formation (N = 10), clearance of bacteria from infected wounds (N = 5), and measurement of nutrient flow by random-pattern flap survival (N = 5). Blood flow levels increased fourfold when 125 mmHg subatmospheric pressure was applied. Significantly increased rates of granulation tissue formation (p less than or equal to 0.05) occurred with both continuous (63.3% +/- 26.1%) and intermittent (103% +/- 35.3%) application. Tissue bacterial counts significantly decreased (p less than or equal to 0.05) after 4 days of application. Random-pattern flap survival significantly increased (p less than or equal to 0.05) by 21% compared to controls. We determined that the application of controlled subatmospheric pressure creates an environment that promotes wound healing.