A wound dressing includes a chamber defining a treatment space and at least one opening communicating with the treatment space. In one embodiment, a plurality of channels are defined on an inner wall of the chamber. In another embodiment, a tube extends through the chamber and into the treatment space and defines a plurality of openings in a portion of the tube extending into the treatment space. In yet another embodiment, a tube extends through the chamber and into the treatment space and comprises a plurality of branches extending to different regions of the treatment space.
