Bedding or seat device featuring a first cushion which includes the following, a device of insuring a localized compression - decompression of the tissues around the bed sores, a device to avoid all contact with the bedsore itself, and a device to insure a continued ventilation of the bed sore, the first...http://www.google.ca/patents/US4777679?utm_source=gb-gplus-sharePatent US4777679 - Inflatable cushion with central opening
