Negative pressure wound therapy achieved by vacuum-assisted closure: Evaluating the assumptions.

Wounds and the accompanying loss of skin integrity often place a patient at increased risk for disability or death. Billions of dollars are spent each year to treat wounds and the effectiveness of these different treatments is highly variable. Following a 1997 publication describing a new treatment therapy that involved creating negative pressure over the wound, many publications have described the purported mechanism of action by which negative pressure may help wounds heal. Although this therapy appears effective, it remains unknown whether it is more effective than other wound closure techniques. In addition, although many uncontrolled, non-randomized studies describing the effectiveness of this therapy have been published, few prospective randomized trials have been conducted. Small sample sizes, variable outcome measures across studies, and significant methodological problems in the available randomized control trials further limit the conclusions that can be drawn regarding the relative effectiveness of vacuum-assisted wound closure. Analysis of these data provides weak evidence to suggest that negative pressure therapy is superior to saline gauze dressings in healing chronic wounds. Randomized controlled trials comparing healing, costs of care, patient pain, and quality-of-life outcomes of this treatment to non-gauze type dressings and other treatment modalities are needed.