Abstract: A system and method for determining the dry weight wgtdry(t) of a patient at a time t by determining the extracellular water volume ECV(t) and the weight Wgt(t) of the patient at time t and by deriving the dry weight wgtdry(t) of the patient from an intersection of a function derived from the determined ECV(t) and Wgt(t) values with a previously established extracellular water volume (ECV) against dry weight (wgtdry(t)) reference relation representing healthy subjects. To obtain more accurate results it is also proposed to take into account a compartmental mass correction ?m(t). The invention also relates to a device for deriving the dry weight wgtdry(t).

Abstract: The invention makes use of a certain compartmental model to relate various measurement data from a patient to these compartments which in turn enable conclusions about the hydration and/or nutrition status of the patient to be drawn. According to the invention a method is provided for determining the volume ECVhydr(t) of a body compartment of a patient at a time t comprising the steps of determining at least one anthropometric measure X(t) of the patient at the time t, determining the extracellular water volume ECV(t) of the patient at the time t, determining the intracellular water volume ICV(t) of the patient at the time t, deriving the extracellular water volume ECVbasic(t) of a first compartment with weight Wbasic(t) of the patient at the time t by using X(t), deriving the extracellular water volume ECVsec(t) of a second compartment of the patient at the time t by using ICV(t), and deriving ECVhydr(t) as the extracellular water volume of a third compartment of the patient with weight Whydr(t).

Abstract: The invention relates to a method and a device for monitoring the fluid status of a patient with kidney failure. In case of renal failure all forms of ingested fluid accumulate in body tissues causing increased stress on the circulatory system. This surplus fluid has to be removed during a dialysis treatment by ultrafiltration of the blood. The amount of this surplus fluid or the weight corrected for this surplus fluid, i.e. the dry weight, is an important parameter for managing the fluid status of a dialysis patient.