Abstract: Apparatuses, devices, systems and methods for detecting access disconnection are provided. The present invention includes electrical contacts in fluid and electrical communication with a fluid passing between a patient and a medical system during therapy. In this regard, the present invention can use a direct-contact measurement to detect access disconnection, such as dislodgment of an access device from the patient through which fluid can flow during therapy including, for example, medication delivery, dialysis therapy and the like.

Abstract: Apparatuses, devices, systems and methods for detecting access disconnection during medical therapy are provided. The present invention includes an electric circuit coupled to, for example, a blood circuit used during dialysis therapy. The electric circuit can be adapted to inject an electrical signal into the blood circuit such that changes in an electrical value in response to access disconnection, such as needle dropout or catheter drop-out, can be effectively detected.

Abstract: An apparatus for detecting dislodgement of a needle inserted into a patient is provided comprising a sensor capable of detecting wetness due to blood and a sensor holder adapted to secure the sensor to the patient such that the sensor detects wetness due to blood loss from the patient upon dislodgement of the needle. Methods and apparatuses for detecting, monitoring and/or controlling blood loss from a patient due to needle dislodgement are also provided.

Abstract: A flow rate measurement system and method suitable for monitoring filtrate flow in a hemodialysis apparatus, provides a pair of flow meters in series at the input of a dialyzer for producing electrical signals indicative of dialysate flow rate and a pair of flow meters in series at the output of the dialyzer for producing electrical signals indicative of dialysate plus filtrate flow rate. A computer receives the flow rate signals and is programmed to calibrate each flow meter during a calibration phase to correct for any variations in each pair to thereby produce corrective scale factors. During an operational phase of the apparatus, the program monitors the flow meters and provides an alarm if any changes between the readings of either of the pairs of flow meters occurs.

Abstract: A preferred patient blood treatment system for the photoactivation of reagents in contact with a patient's blood employs an infusion pump for adding anti-coagulation reagent to the blood during extracorporeal operations. The infusion pump is preferably driven by a stepper motor and monitored by a periodic photo chopper employing a plurality of sensors. The spacing of the sensors and the spacing of the photo choppers work in concert to detect rotation of the stepper motor and to discriminate such from stutter or other characteristic nonrotational faults associated with stepper motors.