Medical dressing to treat sucking chest wound and methods of forming same

A method to form a medical dressing comprising:

• overlaying a cover layer on an intermediate layer and the intermediate layer on a base layer such that a first opening in the base layer and a second opening in the intermediate layer are aligned and the cover layer overlays the first and second openings;
• fusing together the cover layer, the intermediate layer and the base layer by applying a welding tool face to at least one of the cover layer and base layer, wherein the welding tool face extends around the first and second openings and fuses the base layer to the intermediate layer around the first and second openings and fuses the cover layer, intermediate layer and base layer around the first and second openings except at a slot extending beyond an outer edge of the cover layer and ending before an outer edge of the intermediate layer;
• and
• applying an adhesive layer on a side of the base layer opposite to the intermediate layer, wherein the adhesive layer extends around the first opening.