The urea rebound phenomenon (Ru) after hemodialysis has been reported recently. The present study was made in an attempt to clarify the influence of Ru on normalized dialyser urea clearance (Kt/V'), time averaged concentration of blood urea nitrogen (TACBUN) and protein catabolic rate (PCR). A significant correlation was found between the Ru and Kt/V, while no significant correlation was seen between the Ru and PCR. These results indicate that the Ru is dependent on the efficiency of hemodialysis. The different values of Kt/V, TACBUN and PCR were calcuated using BUN values at the end of hemodialysis and 30min after dialysis, and compared. When calculating Kt/V, PCR and TACBUN using BUN values obtained immediately after hemodialysis, Kt/V and PCR were overestimated by about 15.6% and 8.5%, respectively, and TACBUN was underestimated by 4%. These results indicate the necessity of taking the Ru into account when determining whether or not the patient is receiving optimal dialysis.
Advances in the hemodialysis therapy have been made recent years. It is, however, still important for chronic hemodialysis patients to control the diet and water intake. So, in 76 patients who had been on chronic hemodialysis for more than one year, we analyzed absolute weight gain (gain during the two-day interval between two sessions of hemodialysis) and percentage of weight gain [(absolute weight gain/dry weight) × 100] in relation to normalized dialysis urea clearance (Kt/V), time averaged concentration of blood urea nitrogen (TACBUN) and protein catabolic rate (PCR), and also in relation to protein, energy, salt and potassium intake. PCR had a signifi cant correlation with both the absolute weight gain (r=0.329,P<0.01) and the percentage of weight gain (r=0.349,P<0.01). Protein, energy, salt and potassium intake also correlated significantly with bothparameters. These results suggest that weight gain is closely rlated to the amount of food intake like water intake. Dry weight (DW) cor related significantly with absolute weight gain (r=0.392,P<0.0005), while it did not correlate significantly with percentage of weight gain. This suggests that patients with large DW tend to be inappropriately restricted as to their water intake to counter weight gain acthually caused by excessive food ingestion, and that patients with small DW tend to be erroneously subjected to an excessively limited diet for the purpose of suppressing weight gain.