Foams may have a waterproof film covering on their top surface. Often this film covering is the same material as a transparent film dressing. The foams may also have an adhesive coating over the wound contact side or as a border on their perimeter. Foams also are available in island configurations. At least one brand of foam contains a surfactant within the foam to aid in its fluid handling properties.
Foams are an appropriate choice for managing wounds with moderate to heavy drainage.
The cellular structure of the foams allows them to absorb wound draining and pull it away from the wound bed, thereby decreasing maceration as compared to traditional absorbent gauze products. The fact that their physical bulk and softness provide a cushion and are often comforting and comfortable to the patient is an additional benefit. It may be difficult to retain a foam sheet in a gluteal fold, for example. There are several brands of extra thin foams available. These products have a top film coating that makes them waterproof and are coated on one side with a very mild adhesive.