Percutaneous access device

A percutaneous access device implantable in humans for periods of up to a year or longer to permit access to the body through the skin comprising:

• a main body including a substantially flat, disk-shaped skirt and a neck integral with and substantially normal to said skirt, said neck and skirt formed of a biocompatible polyurethane and including a bore therethrough to accommodate a tube;
• to a lower
• a first porous bed surrounding and attached portion of said neck and extending along a portion of the upper surface of said skirt adjacent to said neck, said first porous bed being formed of a polyurethane material which is the reaction product of dicyclohexyl methane diisocyanate, polytetramethylene ether glycol, and 1,4 butane diol and including a multiplicity of interconnected pores having a size in the range of about 50-125 microns so that upon implantation of the skirt just below the dermis, said pores permit downgrowth of epidermal cells through said bed at a controlled rate substantially without allowing wicking of body fluids upward to a point external to the body;
• and
• a second porous bed forming a junction on said skirt with one end of said first bed, said second porous bed attached to and covering the portion of the skirt not overlain by said first bed and including pores of a size in the range of about 400-800 microns so as to permit infiltration of fibroblasts and formation of collagen in said pores;
• said beds promoting the formation of a stable, tight, infection-free biologic seal between said beds and adjoining tissue.