Method for making a polyvinyl acetal sponge packing for use in the nasal, sinus and otic cavities

摘要

Nasal, sinus and otic packings exhibiting a less adherent surface when in contact with tissue and being less traumatic on removal are prepared. In a first embodiment, polyvinyl acetal foamed packing material undergoes a surface modification imparting a non-adherent hydrogel coated surface. The surface modification is accomplished after final processing and fabrication of the packing product shape. The packing material is subjected to either an atomized spray of an aqueous solution of ethyl alcohol or a polyvinyl acetate/polyvinyl alcohol copolymer. In another embodiment, a foamed polyvinyl acetal material is produced by crosslinking polyvinyl alcohol with an organic compound containing two hydroxyl reactive groups in the presence of an inert gas. An aqueous solution containing polyvinylpyrrolidone is mixed into the reaction during crosslinking. The recovered sponge material foam product is cut or molded into a packing thereby resulting in the production of a packing having a uniformly dispersed gel throughout and as an outer hydrogel coating. Nasal, sinus and otic packings prepared by these methods exhibit a less adherent surface upon contact with tissue and are far less traumatic to the tissue upon removal.