Wound dressing

An apparatus for the treatment of a wound by applying negative pressure to the wound, the apparatus comprising:

• a wound contact layer comprising a plurality of perforations through the wound contact layer that allows for fluid to pass there through;
• a porous layer disposed over the wound contact layer configured to allow transmission of fluid away from a wound site and distribute negative pressure, through the wound contact layer, over the entire portion of the wound site being treated;
• an absorbent material configured to form a reservoir for fluid removed from the wound site, the absorbent material being disposed over the porous layer;
• a cover layer configured to cover the absorbent material, wherein the absorbent material acts as a waste container to collect and store all liquid removed from the wound site below the cover layer;
• a hole in the cover layer;
• a filter positioned at the hole in the cover layer, wherein the filter is configured to permits gas to pass through and to prevent the passage of liquid past itself;
• a pump configured to apply negative pressure to the wound site through the perforations in the wound contact layer and through the porous layer and configured to draw fluid from the wound site into the absorbent material, wherein the pump is configured to apply negative pressure directly to a zone entirely below the absorbent material through a fluid path that does not contact the absorbent material.