A patient supporting surface for use with a conventional operating room table having at least one pad for supporting a patient, wherein the pad has a chamber for containing a quantity of fluid. The chamber is a dual-layer, urethane envelope having an upper and lower portion. The fluid contained within...http://www.google.es/patents/US6578219?utm_source=gb-gplus-sharePatente US6578219 - Mattress overlay for operating room table
