US Patent 7617555 Patient support surface

A support surface is configured to support a patient thereon and has a base portion that includes an air cushion layer. The support surface also has a layer of three dimensional engineered material above the base portion. The layer of three dimensional engineered material is configured to permit air passage therethrough. The layer of three dimensional engineered material is made of a material other than foam. A cover is positioned between the layer of three dimensional engineered material and the patient to be supported. Air is forced through the layer of three dimensional engineered material.