Hydrogel wound dressing

A composite wound dressing comprising a layer consisting essentially of hydrogel adapted for absorption of exudation from said wound;

• an adhesive material for adhering the dressing to the skin surrounding the wound;
• an outer oxygen- and vapor-permeable layer for permitting transpiration of liquid from said dressing to ambient air;
• and a removable vapor impermeable sheet material releasably secured on the outer surface of said oxygen- and vapor-permeable layer;
• said adhesive material being present in a layer between said outer layer and said hydrogel layer, said hydrogel layer having smaller surface dimensions than said adhesive layer, whereby said adhesive layer has free surface areas extending beyond the periphery of said hydrogel layer for adhering said dressing to the skin.

A wound dressing adapted for preventing pooling of wound exudate and for promoting healing comprising, in order:

• (a) a layer consisting essentially of hydrogel for placement on a wound, said hydrogel being characterized as being wound friendly and for absorbing and acting as a reservoir for wound exudate, said hydrogel further being characterized as being fluid-permeable whereby said exudate can diffuse, at least in part, through said hydrogel layer toward the outer surface of said dressing;
• (b) an intermediate layer disposed over said hydrogel layer and having greater dimension than said hydrogel layer whereby portions of said intermediate layer extend beyond the periphery of said hydrogel layer, said extended portion of said intermediate layer having an adhesive surface for adhering said dressing to the skin, wherein said adhesive surface comprises a pressure-sensitive absorbent adhesive, said intermediate layer comprising a tacky hydrogel or hydrocolloid adhesive, said tacky hydrogel or hydrocolloid adhesive characterized as having a greater absorbent capacity than does the hydrogel of said hydrogel layer underlying said intermediate layer;
• said underlying hydrogel layer is characterized as being more wound friendly and consequently more suitable for direct wound contact than the tacky hydrogel or hydrocolloid adhesive of greater absorbent capacity;
• said intermediate layer having sufficient moisture permeability to permit at least a portion of wound exudate to diffuse therethrough to the outer surface of said dressing;
• and
• (c) an outer oxygen- and vapor-permeable layer adapted for transpiration of at least a portion of fluid diffusing through said dressing.