Lee Kyungsoo, Jeong Jae Hoon, Mun Cho Hae, Lee Sa Ram, Yoo Kyu Jae, Park Yong Woo, Won Yong Soon, Min Byoung Goo
Interdisciplinary Program in Biomedical Engineering, Seoul National University, Seoul, Korea.
Artif Organs. 2007 Aug;31(8):653-8. doi: 10.1111/j.1525-1594.2007.00436.x.
Internal filtration contributes to convective clearance in high-flux hemodialysis but its contribution is limited by low pressure gradients. Therefore, a modification using a conventional dialyzer was conceived to enhance internal filtration and backfiltration (BF) rates. The modified dialyzer includes two longitudinal independent regions for blood flow, which were created by redesigning dialyzer caps. Blood pressures remained higher than dialysate pressures in one region and lower in the other region, allowing continuous internal filtration and BF in these respective regions. Modified and conventional dialyzers were compared in terms of pressure gradients and solute clearances. Thus, our experiments involved two groups: the modified dialyzer group and the conventional dialyzer group. A renal failure model was established using a dog weighing 25-30 kg by renal artery and vein ligation. With the exception of the dialyzers, experimental conditions were identical in the two groups. The pressure gradients between blood and dialysate were much higher for the modified dialyzer than for the conventional dialyzer. No significant differences were observed with respect to small solute clearances between the two groups, but mid-range solute clearances were significantly higher in the modified group. More optimization is required before the devised unit can be used clinically. However, the devised unit offers a straightforward means of regulating internal filtration and BF rates.
在高通量血液透析中，内部过滤有助于对流清除，但由于压力梯度较低，其作用有限。因此，人们设想对传统透析器进行改进，以提高内部过滤和反向过滤（BF）速率。改进后的透析器包括两个用于血液流动的纵向独立区域，这是通过重新设计透析器帽来实现的。在一个区域中，血压保持高于透析液压力，而在另一个区域中则较低，从而在这些相应区域实现连续的内部过滤和BF。对改进型和传统透析器在压力梯度和溶质清除方面进行了比较。因此，我们的实验涉及两组：改进型透析器组和传统透析器组。通过结扎肾动脉和肾静脉，使用体重25-30 kg的狗建立肾衰竭模型。除了透析器外，两组的实验条件相同。改进型透析器的血液与透析液之间的压力梯度比传统透析器高得多。两组之间在小溶质清除方面未观察到显著差异，但改进组的中程溶质清除显著更高。在该设计装置能够临床应用之前，还需要更多的优化。然而，该设计装置提供了一种调节内部过滤和BF速率的直接方法。
