A device (26) carries a use monitoring element (82,114) that possesses a state or condition that changes in response to use of the device and that is sensed when the device is presented for use. Reuse of the device is not permitted if the use monitoring element (82, 114) indicates a prior use....http://www.google.co.uk/patents/US6733495?utm_source=gb-gplus-sharePatent US6733495 - Systems and methods for monitoring and controlling use of medical devices
