[Continuous determination of the blood density during haemodialysis (author's transl)].

Application of the mechanical oscillator technique for measurement of blood density, in combination with a reference method for the determination of the absolute value of the blood volume, enables precise and continuous monitoring of fluid shifts during haemodialysis. The significant correlation between blood volume and density or plasma volume and density allows each variation in blood volume to be calculated from the blood density and the slope of the regression line for each individual patient. The possibility of taking continuous measurements and the high accuracy of the mechanical oscillator technique commends this method for the measurement of short-term and small fluid shifts.