Patent ID: 6979306

Claim:
A hemodialysis site sensor attachable to at least one of a blood line and a fistula needle for alerting medical personnel of the leakage of blood from an access site where the fistula needle enters into a patient's body and dislodgment of the fistula needle from the access site, the hemodialysis site sensor comprising: a base membrane layer made of a medical-grade, biocompatible material and including an upper side, a lower side adherable to skin of the patient, and one or more holes disposed therein to allow the passage of blood and vapor therethrough; a second membrane layer including an upper side, a lower side, and one or more holes disposed therein to allow the passage of blood and vapor therethrough; a third membrane layer including an upper side and a lower side; an electrical connection adapted to be electrically coupled to an analytical circuit and including a first sensing array disposed between the upper side of the base membrane layer and the lower side of the second membrane layer, a second sensing array disposed between the upper side of the second membrane layer and the lower side of the third membrane layer, and resistively connected to the first sensing array; a disconnection mechanism attachable to at least one of the blood line and the fistula needle and severing the electrical connection upon dislodgment of the fistula needle from the access site; wherein an electrical signal sent through the electrical connection changes when blood contacts at least one of the sensing arrays or the electrical connection is severed by the disconnection mechanism, causing the analytical circuit to actuate an alarm notifying medical personnel of partial or total dislodgment of the fistula needle from the access site.