A wound dressing includes a chamber (12) defining a treatment space (14) and at least one opening (20) 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 (31) extends through the chamber and into the treatment space and defines a plurality of openings (35) 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 (37) extending to different regions of the treatment space.
