Patent attributes
An access needle for extracorporeal therapy is equipped with a mount and a sleeve having a metal or magnetic component at its distal end. The mount includes a sensor for detecting when the distal end is pressed against the mount. The sensor is a hall-effect sensor or a proximity sensor. When therapy is begun, the sleeve is rolled up and urged against the mount, exposing the needle for use with the patient. While the sleeve, and the piece of metal or magnet, remains in contact with the sensor, the needle has not been dislodged and therapy may continue. If the needle is dislodged, the sleeve pushes away from mount, moving the metal or magnet away from the sensor. The sensor notes the dislodgement and sends a signal to alert the patient or a caregiver.
