| [ Summary ] |
Internal filtration enhanced hemodialysis (IFEHD), defined as a type of HD therapy using a dialyzer designed for enhanced internal filtration / backfiltration (IF / BF), is expected to have a higher solute removal efficiency than that with conventional HD. This is because enhanced IF flow rate increased convective transport of the solute in addition to diffusive transport. Several kinds of monitoring techniques, such as Doppler ultrasonography, have been introduced to measure internal filtration flow rates (QIF). This is, however, a bit complicated because an ultrasonic instrument and a probe slider in the water bath are required as special equipments. A simple estimation of maximum QIF value, based on analytical study, was introduced in this paper. We assume that the value of mean transmembrane pressure (TMP) is about one-fourth the value of that on the arterial side, TMP (0), because the mean positive TMP region has half-length of the dialyzer and half of the height of the TMP profile. The QIF value could be estimated as UF x TMP (0) where UF indicates the ultrafiltration coefficient. The time decay ratio for the QIF value seemed to be precisely estimated with this method. |