To explore effects of hemoperfusion (HP) with different frequencies on the clearance of serum solutes in patients with maintenance hemodialysis (MHD) , and to provide a practical basis for the reasonable clinical application of HP.

By the convenient sampling method, a total of 132 patients who underwent MHD in Blood Purification Center of Beijing Friendship Hospital Affiliated to Capital Medical University were selected as research objects from January to October 2019 and they were randomly divided into group A, group B, group C and group D. Group A received high-flux hemodialysis. On the basis of group A, HP was added to group B, group C and group D respectively for once every 2 weeks, once per week and twice per week. They were observed for 12 weeks. The serum solute indexes such as calcium, phosphorus, parathyroid hormone (PTH) , C-reactive protein (CRP) , β ₂-microglobulin (β₂-MG) and malondialdehyde (MDA) and coagulation function were compared among the four groups.

In group D, 2 patients failed to complete the HP frequency of the prescribed plan in the 6th and 10th weeks respectively and were excluded, and the reasons were both gastrointestinal bleeding. Finally, a total of 31 patients in group D completed the study. All patients in group A, B and C were without bleeding and completed the study. After intervention, the indexes of phosphorus, PTH, CRP, β ₂-MG and MDA in groups B, C and D were lower than those in group A, and the differences among the 4 groups were statistically significant (P<0.05) . The calcium, phosphorus and CRP indexes of group B after intervention were lower than before intervention, and the differences were statistically significant (P<0.05) . The indexes of calcium, phosphorus, CRP, PTH, β₂-MG and MDA after intervention in group C and group D were all lower than before intervention, and the differences were statistically significant (P<0.05) .SNK-q test showed that except for group C and group D, there were statistically significant differences in blood calcium between the other two groups (P<0.05) . There were statistically significant differences in blood phosphorus between group A and Group C and between group A and Group D (P<0.05) . Among the 4 solutes including PTH, CRP, β₂-MG and MDA, there was no statistically significant difference between group A and group B, and between group C and group D (P>0.05) , while other pair comparisons showed statistically significant differences (P<0.05) . The prothrombin time in group C after intervention was higher than that before intervention, and the difference was statistically significant (P<0.05) . The prothrombin time, partial thromboplastin time and fibrinogen after intervention in group D were all higher than those before intervention, and the differences were statistically significant (P<0.05) . After intervention, the prothrombin time, partial thromboplastin time and fibrinogen in group D were higher than those in groups A, B, and C, and the differences were statistically significant (P<0.05) .

The combination of HP on the basis of high-flux hemodialysis is more conducive to clearing the serum solutes of medium and large molecules in patients, and better results can be achieved with the frequency of once a week. Excessive HP frequency may have the disadvantages of bleeding risk and high cost.

Hemodialysis; Hemoperfusion; Different frequencies; Serum solute