本研究利用Three-pore model模擬在使用Icodextrin溶液的腹膜透析(peritoneal dialysis)療程中因血液中殘留一定量的Icodextrin濃度造成超濾(ultrafiltration)行為的改變。Icodextrin與傳統葡萄糖透析液相比，由於高莫耳重量的特性，Icodextrin不論在短期或長期的腹膜透析療程中都擁有良好且穩定的超濾行為。一般使用Icodextrin透析液的病人血液中Icodextrin濃度會上升。Icodextrin要從人體中排出約略需要7天左右，所以使用Icodextrin透析液的病人血液中會殘留Icodextrin濃度。在模擬結果中，殘留於血液中的Icodextrin濃度會造成腹膜透析中超濾行為降低。在使Icodextrin與葡萄糖的混合透析液的案例中可以明顯看出殘留的Icodextrin濃度會造成類似的影響。
人體系統的變化是造成腹膜透析超濾行為產生變化的眾多因素之一。本研究中討論直接淋巴吸收(direct lymphatic absorption)和微血管面積兩個因素改變所造成的影響。模擬結果發現直接淋巴吸收增加會造成超濾行為下降。血液中Icodextrin的殘留會使小幅度變化的直接淋巴吸收就可能造成腹膜透析無法發揮正常作用。微血管面積的改變在短期療程中使用Icodextrin透析液無法造成腹膜透析的作用下降。但從模擬的結果發現，在長期療程中會發現Icodextrin溶液也可能會有不良的超濾行為的產生，血液中殘留的Icodextrin濃度會造成超濾作用更大幅度的下降。

This study used a three-pore model in peritoneal dialysis (PD) ultrafiltration simulations using an icodextrin-based dialysate solution. This paper discusses the ultrafiltration profiles with residual icodextrin concentrations in blood. Due to icodextrin has a higher molecular weight than that of glucose, the peritoneal dialysis using the icodextrin solution exhibits favorable and stable ultrafiltration profiles both in short term and long-term treatment. In general, patients using icodextrin may have residual icodextrin concentrations in the blood. The icodextrin was absorbed continuously during PD. The increasing icodextrin concentration in blood caused overestimations of icodextrin permeability surface area (PS) values. Therefore, the PS values of icodextrin have to be modified in the simulations.
Body system variations are one of the factors causing the changes of ultrafiltration profiles in peritoneal dialysis. In this study, variations of direct lymphatic absorption and the vascular surface area cause the impact in both the simulations and clinical experiments. The results of the simulations showed that the increased direct lymphatic absorption diminish the effect of ultrafiltration. Due to the minor changes in direct lymphatic absorption, caused by the residual icodextrin concentration, the peritoneal dialysis may not work properly. The variations of the vascular surface area do not diminish the ultrafiltration profiles in the short-term treatment using icodextrin dialysate solution. However, simulation results show that the ultrafiltration behavior may produce less favorable effects using the icodextrin solution in the long-term dialysate treatment. The residual icodextrin concentrations cause the most significant decline among the ultrafiltrate profiles.
The result shows that the residual icodextrin concentrations of the blood cause the least favorable ultrafiltration behavior. In the case using a simple glucose dialysis solution or combined solution with glucose and icodextrin, the residual icodextrin concentrations cause similar effects.

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