A wound therapy apparatus for enhancing healing of a wound includes a wound dressing configured for placement over the wound to define a reservoir over the wound in which a wound contact fluid may be maintained by forming a substantially fluid-tight seal around the wound. An elastic bladder member defined by or within the wound dressing is expandable to exert a pressure on the wound contact fluid within the reservoir. A fluid system is in fluid communication with the reservoir for selectively delivering the wound contact fluid to the reservoir, and a pressure system is in fluid communication with the bladder member for delivering a compressed liquid or gas to the bladder member to effect expansion in the bladder member.
