Improvement of Decisions Regarding Hemodialysis Patients by Urea Kinetic Modeling

Abstract

The potentials for improving decisions about adequacy of dialysis (AD) and daily protein intake (DPI) by urea kinetic modeling (UKM) were examined. Four nephrologists evaluated AD, DPI, and metabolic stability in 62 patients. UKM was done three times; but the results were not revealed. Clinicians' decisions were then compared with UKM measures of effective dialysis (Kt/V) and protein catabolic rate (pcr). Detection of inadequately treated patients by the clinicians was poor (28%, Kt/V less than 1.0; and 40%, Kt/V less than 0.9). Specificities of the clinicians' decisions were 0.96 and 0.92, respectively. Combining pcr and consensus decisions, 59 patients could be assigned a probable DPI. Using this as "gold standard," the average clinician detected 77% of 13 low DPIs. Single or triple pcr determinations alone detected 77% or 62%, respectively. Specificities were 0.91, 0.85, and 1.0. Simulated decision making suggested that combining pcr with clinical evaluation in a logical way would lead to detection of most patients with low DPI. Qualitative data from individual patient cases causing controversies are presented and discussed. It is concluded the UKM should be used routinely to assess the adequacy of dialysis and daily protein intake.