| 摘要 |
A method and apparatus for calculating the mass of a composition in a fluid volume or efficiency of exchange of said composition with an exchange fluid, especially urea in the body of a dialysis patient. Calculations are based on total mass of urea in the body. The concentration cd of urea in the effluent dialysate is measured, and the total removed mass U of urea is calculated by integrating the product of the urea concentration cd and the dialysate flow Qd. The momentary relative efficiency of the removal (K/V) is determined essentially by calculating the slope of the logarithm of the concentration curve and the momentary mass is determined therefrom. Then, the pre-treatment mass of urea in the body can be determined very accurately. Moreover, the momentary relative efficiency in any point is determined by using the removed urea U. The dialysis dose is calculated by integrating the momentary efficiencies. |
