雙重過濾血漿析離術過濾效能之比較－－Kuraray KM8800及Asahi Plasauto iQ

A Comparative Study of Filtration Efficacy in Double Filtration Plasmapheresis－Kuraray KM 8800 versus Asahi Plasauto iQ

雙重過濾血漿析離療法(double filtration plasmapheresis，DF)可以半選擇性除去血中乙＊膽鹼受體抗體，而改善重症肌無力病人之重度無力現象。DF療法之療效完全取決於血漿分離器及血漿成份分離器之過瀘效能。我們以DF療法治療24例重度重症肌無力病患，其中16例採用Kuraray公司之KM8800血漿分離機，另8例則採用Asahi公司之Plasauto-iQ血漿分離機。治療中我們連續監測血流速度、動脈壓、靜脈壓，及穿膜壓以期了解血漿分離器之過濾效能。另於療程前後各檢測血中蛋白質濃度，包括白蛋白、球蛋白、免疫球蛋白、膽固醇、脂蛋白、三酸甘油脂和血球計數，以評估血漿成份分離器之過濾性能。DF治療中，穿膜壓逐漸上升，而其它動脈壓，靜脈壓，及血流速度則相對穩定。比較兩組可以發現，Asahi組之治療初期穿膜壓與動脈壓略低於Kuraray組(p<0.001)。唯在過高之全程穿膜壓（壓力＞50mmHg）及溶血發生率上，兩組未見顯著差異。至於血漿中免疫球蛋白G及免疫球蛋白A的清除率，在Kuraray組略高於Asahi組，分別是65.4% vs. 45.6%，(p<0.005)及72.7% vs. 55.7%，(p<0.001)。因此，兩組間初期穿膜壓之差異應與動脈壓之差異有關，而與血漿分離器設計應無直接相關。至於血漿物質之清除率，血漿成份分離器之膜面積應是一重要之決定因素。

Double filtration plasmapheresis(DF)alleviates the profound weakness of patients with myasthenia gravis (MG), by semiselectively removing acetylcholine receptor antibodies. The Efficacy in DF depends on the functional capacity of both the plasma separator and the fractionator. We treated 24 MG patients with DF,using either the Kuraray KM 8800(Kuraray Co., Osaka, Japan)(n=16)or the Asahi Plasauto iQ(Asahi Medical Co., Tokyo, Japan)(n=8) plasmapheresis monitor. To evaluate the filtration efficacy of plasma separators, we monitored the blood flow rate (BF), arterial pressure (PA), venous pressure (PV), and transmembrane pressure (TMP) serially during treatment. To assess the efficiency of the plasma fractionators, we measured levels of the serum proteins, including albumin and globulin, immunoglobulin (Ig) G, IgA, IgM, cholesterol, lipoproteins, and triglycerides, and obtained complete blood counts, before and after plasmapheresis therapy. The TMP rose gradually and the PA, PV, and BF were relatively constant during DF treatment. The initial TMP and PA were significantly lower (p<0.001) in the Asahi group than the Kuraray group. However, the percentage of patients with unsatisfactory TMP levels (TMP > 50 mmHg) and hemolysis were not significantly different between the two groups. The median removal rate of IgG and IgA were significantly higher in the Kuraray group (65.4% vs 48.6%, (p< 0.005); and 72.7% vs 55.7%, (p<0.001), respectively). The differences in the TMP changes between the two groups may be related to the changes in the PA itself rather than the column design. As for the removal rate of serum protein, the surface membrane of the plasma fractionator may be a crucial factor in the treatment of DF.