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 < or = 0.05) occurred with both continuous (63.3 +/- 26.1%) and intermittent (103% +/- 35.3%) application. Tissue bacterial counts significantly decreased (p < or = 0.05) after 4 days of application. Random-pattern flap survival significantly increased (p < or = 0.05) by 21% compared to controls. We determined that the application of controlled subatmospheric pressure creates an environment that promotes would healing.