US Patent 9913757 Vacuum wound therapy wound dressing with variable performance zones

A dressing for an open wound includes a cover layer dimensioned for positioning relative to a wound bed. The cover layer permits an evacuation of the space around the wound bed such that a sub-atmospheric pressure may be established to stimulate healing and facilitate the removal of fluid from the wound. Multiple performance zones in the cover layer allow the wound dressing to remain in position through repeated cycles of evacuation without placing undue strain on the wound bed. An outer peripheral zone may include a high peal-strength adhesive while an intermediate zone may include a shear resistant adhesive. A central zone may be devoid of any coating to maximize moisture transmission through cover layer.