Evaluation of a new method for pulse push/pull hemodialysis: comparison with conventional hemodialysis.

: The repetition of forward and backward filtration during hemodialysis (HD) increases convective mass transfer, and thus, the authors devised a method of achieving cyclic repletion of ultrafiltration and backfiltration. Hemodialytic efficiencies of the developed unit are described. The devised method, named pulse push/pull hemodialysis (PPPHD), is based on the utilization of dual pulsation in a dialysate stream. Clearances of solutes with different molecular weights were determined, and in vivo hemodialytic performance was investigated in a canine renal failure model. Urea and creatinine reduction and albumin (ALB) loss were monitored, and the results obtained were compared with those of a conventional high-flux hemodialysis (CHD). Dialysis sessions were repeated eight times for PPPHD and six times for CHD by alternating PPPHD and CHD sessions in a single animal, which remained stable throughout the experiments. Urea and creatinine reductions for the PPPHD unit were 49.2 ± 2% and 44.3 ± 3.3%, respectively, which were slightly higher than those obtained for the CHD. Total protein and ALB levels were preserved by both methods. However, in vitro results revealed that PPPHD achieved significantly greater inulin clearance than CHD. The developed PPPHD unit facilitates repetitive filtration and improves convective mass transfer during HD, without the need for external replacement infusion.