Modeling on-line urea sensor-measurements during hemodialysis

On-line urea concentration monitors have been recently developed for the real-time supervision of hemodialysis. The information on urea kinetics provided by on-line sensors must be interpreted taking into account also deterministic patterns related to technical characteristics of the measurement device. For this purpose the authors developed a model of urea concentration measurements performed in blood water by a recently developed sensor. Because of the tight relationship between urea measures and urea clearance, physical and physiological factors affecting dialysis efficiency are taken into account such as blood flows, filter characteristics, cardiopulmonary and access recircularisation.