[Kinetics of phosphorus in individuals on regular dialysis therapy]

In eight subjects with hyperphosphataemia included in regular dialyzation treatment repeatedly phosphorus kinetics (iP) were assessed based on changes in serum concentrations and the amount of iP removed from the organism during every dialysis (D). The serum concentration of iP before dialysis (HD) was on average 3.06 (+/- 0.81) mmol/l and D was on average 55.6 (+/- 10.0) mmol. The value of D calculated per body weight (D/BW) was on average 0.76 (+/- 0.15) mmol/kg. As the differences of predialysis serum concentrations of iP after consecutive HD sessions did not exceed the range of error of analytical assessment of iP, the D values were considered identical with the iP value retained during the interdialysis interval (R). Between values of D/BW and R/BW resp. and the difference of iP serum concentrations at the beginning and end of the interdialyzation interval a significant direct correlation was found (r = 0.715, p < 0.001). From an analysis of this correlation ensues that if the predialysis serum concentration is not to exceed the upper range of the normal value (1.7 mmol/l), the retention of iP in the interdialysis interval must not significantly exceed the value of 0.57 mmol/kg. At the end of the interdialysis interval iP was distributed in the organism in such a way that the extracellular space contained on average 0.38 (+/- 10) from the total retained amount and the remaining portion penetrated into deeper body compartments.(ABSTRACT TRUNCATED AT 250 WORDS)