A piece of foam with an open cell structure is introduced into the wound and a wound drain is placed with lateral perforations on top. The entire area is covered with a transparent adhesive membrane, which is firmly fixed to healthy skin around the wound margin. When the exposed end of the drain tube is connected to a vacuum source, fluid is withdrawn from the wound through the foam into a reservoir for later disposal.It is necessary to cover the wound bed with a soft polyvinyl alcohol foam sponge, a non-stick oil-emulsion dressing (for exame, Johnson and Johnson), a contact layer (such as Mepitel), a thin layer of amorphous hydrogel (can be Intrasite Gel), or a calcium alginate (such as Sorbsan) before application of the gray sponge. Avoid the use of Vaseline, which is too oily and can alter the adhesion of the VAC cloth.
