CVVHDF前后稀释对不同相对分子质量溶质清除的影响

Effects of different modes of dilution during CVVHDF on the removal of different solutes with different molecular weights

目的 通过建立血液净化连续静-静脉血液透析滤过（CVVHDF）模式前、后稀释方法的体外实验,探讨该模式前、后稀释法对各种不同大小的溶质分子清除效率的影响.方法 建立等容CVVHDF前、后稀释及CVVH单循环（无稀释、无透析）对照体外实验装置,比较不同相对分子质量物质钾（K^＋）、肌酐（Cr）、万古霉素（vancomycin）、胰岛素（insulin）和白细胞介素-6（IL-6）的清除率,实验重复4次（n=4）.结果 CVVHDF后稀释法对K^＋、Cr、Vancomycin和Insulin清除率明显高于CVVHDF前稀释;CVVHDF前、后稀释对IL-6清除差异无统计学意义;对照组Insulin和IL-6实验结束时明显降低.结论 CVVHDF后稀释总体上对各种不同相对分子质量物质清除率高于前稀释,但随着相对分子质量的增大,两者间的差别缩小;对照组提示实验用滤器（AN69）对Insulin及IL-6有吸附作用.

Objective To compare the rates of clearance of different solutes during continuous veno-venous haemodiafiltration （CVVHDF） between pre-dilution and post-dilution.Methods A study in vitro was carried out using model CRRT system with AN69 filter used,which was applied to perform CVVHDF for solutes clearance.The removed amounts of different solutes including potassium ion （K ＋）,creatinine （Cr）,vancomycin,insulin,and interleukin-6 （IL-6） were determined in the groups of control （without dilution）,pre-dilution and post-dilution during CVVHDF at the same substitution fluid amount.Each group was repeated 4 times （n =4）.Results Post-dilution mode increased K ＋,Cr,vancomycin and insulin clearances significantly.There was no difference in clearance of IL-6 between the pre-and post-dilution groups.In the control group,insulin and IL-6 levels were decreased extremely.Conclusions In general,the rate of clearance using post-dilution of CVVHDF is higher than that using pre-dilution.Among high molecular weight solutes,the difference in clearance is not significant.The control group demonstrates insulin and IL-6 adsorbed by the filter.