国产PES14LF聚醚砜透析器对血液透析患者疗效和安全性的临床随机对照试验

目的 评价国产PES14LF聚醚砜低通量透析器对维持性血液透析（MHD）患者的疗效和安全性。 方法 选择上海两家医院72例MHD患者为研究对象,进行随机平行对照试验。试验组采用国产PES14LF透析器,对照组采用德国F6聚砜膜透析器。检测透析器尿素、肌酐、磷清除率和下降比率,以及试验前后实验室指标。观察及记录不良反应。 结果 两组间尿素、肌酐清除率差异均无统计学意义。试验组磷清除率显著大于对照组[（144.57±27.83） ml/min比（117.15±22.77） ml/min,P < 0.05]。试验组尿素下降比率大于65%。两组间尿素、肌酐、磷下降比率差异均无统计学意义。两组间尿素清除有效率和尿素下降比有效率差异均无统计学意义。两组治疗前后实验室评价指标均无明显变化,不良事件少而程度轻,无不良反应。结论 国产PES14LF聚醚砜低通量透析器临床使用安全、有效。     

个性化干预对MHD患者透析充分性的影响

目的：探讨个性化干预措施对维持性血液透析患者透析充分性的影响。方法：选择维持性血液透析患者尿素清除数（Kt/V）小于1.2的患者53例，根据体重、内瘘条件、血液再循环、透析时间、透析器、液体状况等原因，分别进行个性化干预。结果：53例维持性血液透析患者干预后血流量（244.53±24.224）ml/min较干预前（223.40±22.87）ml/min显著增加，透析器膜面积干预后（1.71±0.13）m2较干预前（1.66±0.17）m2也显著增加。患者的Kt/V干预后（1.35±0.19）较干预前（1.07±0.10）显著改善。结论：通过采取个体化干预措施能显著改善维持性血液透析患者的透析充分性。     

霉酚酸酯对糖尿病大鼠肾脏基质金属蛋白酶9、转化生长因子β1表达的影响

目的 探讨霉酚酸酯（MMF）对糖尿病（DM）大鼠肾脏的保护作用及其机制。 方法 将实验动物分为正常对照组、DM组及MMF治疗组。MMF组给予MMF(15 mg/kg,口服,1次/d) 治疗。8 周后检测各组大鼠尿蛋白量（24 h）、内生肌酐清除率（Ccr）、血糖;HE染色观察肾脏病理改变;免疫组化及RT-PCR法检测肾组织中基质金属蛋白酶9（MMP-9）、转化生长因子β1（TGF-β1）的表达。 结果 DM组大鼠血糖[（22.18±3.36） mmol/L比（6.40±0.87）mmol/L]、尿蛋白量（24 h）[（26.80±0.82） mg比（6.64±1.42） mg]、Ccr[（0.220±0.380） ml/min比（0.098±0.015） ml/min]显著高于对照组（P ＜ 0.05）。MMF组的尿蛋白量（24 h）[（16.17±1.15） mg]、Ccr[（0.220±0.380） ml/min比（0.207±0.377） ml/min]均显著低于DM组（P ＜ 0.05）。与DM组比较,MMF组肾小球肿大、系膜细胞增生显著减轻。肾组织中MMP-9在对照组表达较多,主要在肾小球系膜细胞胞质内及肾小管上皮细胞,DM组表达较弱,MMF组介于两组之间,组间差异均有统计学意义（P < 0.05）。TGF-β1在正常对照组大鼠肾组织有少量表达,在DM组表达较强,在MMF组介于两组之间,组间差异亦均有统计学意义（P < 0.05）。 结论 MMF可降低DM大鼠尿蛋白排泄、Ccr,减轻早期肾小球肥大,此作用可能与MMF上调肾组织中MMP-9表达、下调TGF-β1的表达、减少系膜外基质的沉积有关。     

联机在线尿素清除率监测对高通量血透充分性评价的研究

目的：通过血液透析机的在线尿素清除率监测系统（OCM）动态监测以比较高通量血液透析和低通量血液透析对维持性血液透析（MHD）患者的透析充分性以及对中分子物质清除的疗效.方法：80例患者随机分为高通量血液透析组（HFHD组）和低通量血液透析组（LFHD组）,HFHD组使用FX60高通量聚砜膜透析器,LFHD组使用F7低通量聚砜膜透析器,同时使用OCM进行动态监测,比较两组到达设定的Kt/V目标值所需的时间及透析结束时的Kt/V值,同时检测治疗前后血磷（P3＋）、甲状旁腺激素（PTH）、β2微球蛋白（β2-MG）等指标,透析治疗1年后复测并比较上述指标.结果：HFHD组对P3＋、PTH和β2-MG清除明显高于LFHD组（P＜0.01）,一年以后两组比较差异有统计意义（P＜0.01）.结论：HFHD行维持治疗的透析充分性与LFHD差异无统计学意义,但HFHD组对P3＋、PTH和β2-MG的清除效果较LFHD组效果好,HFHD优于LFHD.     

小剂量日间非卧床腹膜透析对残肾功能较好的糖尿病终末期肾病患者的疗效

目的　研究小剂量日间非卧床腹膜透析（DAPD）和小剂量持续非卧床腹膜透析（CAPD）对残肾功能较好的糖尿病终末期肾病（ESRD）患者的疗效。 方法 病情稳定、残肾功能较好（rGFR≥5 ml/min,且尿量≥750 ml/d）的40例糖尿病ESRD患者入选。按数字随机法分为小剂量DAPD组20例和小剂量CAPD组20例。DAPD组透析处方为1.5 L或2 L,3次/d,每次留腹3～4 h,夜间干腹。CAPD组透析处方为1.5～2 Ｌ,3次/d,或1.5 L,4次/d,夜间留腹。在研究开始及6个月后,分别计算两组腹膜尿素氮清除率（Kt/V）、残肾Kt/V、每周总Ｋt/V、Ccr、rGFR等指标;测定24 h尿蛋白量、24 h腹透液蛋白、血清白蛋白、空腹血糖、糖化血红蛋白及胰岛素剂量;用改良主观综合性营养评估法（SGA）评估患者营养状况。 结果 共35例患者完成研究。两组患者年龄、性别、体质量指数、透析龄、透析液肌酐/血肌酐（D/Pcr）等基线值差异无统计学意义。6个月后,CAPD组胰岛素剂量和24 h腹透液丢失蛋白明显高于DAPD组,分别为（33.6±10.9） U/d 比（20.6±6.2） U/d（P < 0.05）和（11.13±4.95） g比（5.66±2.88） g（P < 0.01）,而血清白蛋白明显低于DAPD组[（29.7±4.2） 比（36.5±3.9） g/L,P < 0.05]。DAPD组与CAPD组相比,24 h净超滤量为（554±187） ml比（309±177） ml,24 h尿量为（1090±361） ml比（750±258） ml,rGFR为（8.21±2.40） ml/min比（4.88±2.11） ml/min,DAPD组均显著高于CAPD组（均P < 0.05）。 结论 对于残肾功能较好的糖尿病ESRD患者,小剂量DAPD较小剂量CAPD能更好地控制血糖,改善营养状态及保护残肾功能。     

血清胱抑素C对糖尿病肾病早期诊断的意义

目的：评价血清胱抑素C（Cys-C）,对糖尿病肾病患者早期诊断的价值。方法：应用颗粒增强免疫比浊法测定50例健康体检者和198例糖尿病患者的Cys-C、血清肌酐（Scr）、β2微球蛋白（β2-MG）浓度,同时测量198例患者尿肌酐（UCr）、尿微量白蛋白（MAlb）根据尿量计算出内生肌酐清除率（Ccr）以及24h尿微量白蛋白,并进行比较分析。结果：早期糖尿病肾病组Cys-C（1.63±0.87）、β2-MG（2.60±1.07）和临床糖尿病肾病组的Cys-C（2.29±1.18）、β2-MG（3.19±1.43）均较单纯糖尿病组Cys-C（0.91±0.21）、β2-MG（1.59±0.42）和正常对照组的检测结果明显增高,差异有统计学意义（P〈0.01）;单纯糖尿病组Cys-C、β2-MG、Scr和Ccr检测结果和正常对照组比较差异无统计学意义。早期糖尿病肾病组中,Cys-C、β2-MG和Ccr、Scr阳性率分别为75.4%（46/61）、88.5%（54/61）、32.8%（20/61）、4.9%（3/61）;临床糖尿病肾病组中,Cys-C、β2-MG和Ccr、Scr阳性率分别为87.5%（49/56）、91.1%（51/56）、66.1%（37/56）、50%（28/56）。Cys-C与β2-MG的相关系数,差异有统计学意义（r=0.8418,P〈0.01）。结论：胱抑素C用于评价糖尿病患者的肾功能状况,其特异性好于β2-MG,灵敏度高于Ccr、Scr,是的一个能较好反映肾小球滤过率的指标,对糖尿病肾病早期诊断具有重要的临床意义。     

四种不同膜材料透析器生物相容性的临床研究

目的 观察4种不同膜材料透析器临床应用过程中的生物相容性。 方法 60例维持性血液透析（MHD）患者入选,进行前瞻、随机、对照、队列研究。在基线水平所有患者均应用聚砜（PS）膜透析器透析至少3个月,随后患者按随机数字法分配入3个不同膜材质透析器组：聚醚砜膜（PES）组、三醋酸纤维素膜（CTA）组和聚甲基丙烯酸甲酯膜（PMMA）组,观察6个月。透析器无复用,在不同的时间点测定生物相容性指标进行比较。 结果 血超敏C反应蛋白（hsCRP）、白细胞介素（IL）1β、IL-13、红细胞计数、血小板计数在不同组之间及分组前（0）、3、6个月透析前后进行比较,差异均无统计学意义。透析过程中,血补体C3a、C5a水平均先升后降。PMMA组在0个月时透析0 min、15 min、240 min补体C3a为（117.92±35.99）、（183.09±57.02）、（135.20±43.08） μg/L;在3个月时分别为（96.11±30.84）、（141.48±50.70）、（115.38±37.49） μg/L;在6个月时分别为（85.05±17.28）、（146.31±41.07）、（116.69±32.95） μg/L,0个月分别与3个月、6个月间C3a水平差异有统计学意义（均P < 0.05）。3个月时PMMA组透析0 min、15 min、240 min C5a为（60.59±19.07）、（85.30±23.50）、（72.74±28.97） μg/L,PES组透析0 min、15 min、240 min C5a为（74.70±18.70）、（98.85±27.78）、（83.96±27.87） μg/L,两组间差异有统计学意义（P < 0.05）。白细胞计数（WBC,×109/L）在透析过程中先降后升。PMMA组WBC 0个月、3个月、6个月的透析0 min为（5.60±1.42）、（6.02±1.36)、（6.45±1.29）（均P < 0.05）;15 min为（4.44±0.98）、（2.32±1.11）、（2.20±1.42）（均P < 0.01）;0个月、6个月的透析30 min为（5.64±1.22）、（4.74±1.35）（P = 0.026）;60 min为（5.97±0.82）、（6.82±1.58）（P = 0.39）;240 min为（7.41±1.87）、（8.44±1.61）（P = 0.001）;3个月、6个月的透析240 min为（7.53±2.31）、（8.44±1.61）（P = 0.004）。差异均有统计学意义。 结论 4种膜材料透析器生物相容性存在一定的差异。     

141例维持性血液透析患者血清β2微球蛋白的分布及其相关因素分析

目的观察维持性血液透析患者血清β2微球蛋白的分布,并分析其相关因素。方法分析141例在我院肾脏科进行维持性血液透析患者的病历资料,包括性别、年龄、身高、体质量、24h尿量（残余尿）、透析龄、每次透析平均脱水量、血压、糖尿病史以及血常规、高敏C反应蛋白、血生化、全段甲状旁腺素、胆微球蛋白检查。结果本研究中141例维持性血液透析患者的血清β2微球蛋白均值为（46．9±15．4）mg／L,其中男性、女性患者分别为（45．6±14．7）mg／L、（50．0±16．7）mg／L（t=1．556,P=0．122）。患者平均年龄（54±12）岁,与β2微球蛋白之间无直线相关关系（r=0．021,P=0．801）。患者透析龄（68±61）个月,与胆微球蛋白之间存在直线相关关系（r=0．247,P=0．003）。根据患者24h尿量（残余尿）分组,A组〈100ml,B组100-400ml,C组〉400ml,血清β2微球蛋白分别为（52．6±15．1）mg／L、（45．4±16．2）mg／L、（39．2±11．1）mg／L,3组比较差异存在统计学意义（F=11．431,P=0．000）,线性趋势检验提示随着尿量的减少β2微球蛋白呈增加趋势（Ffortrend=22．829,Pfortrend=0．000）。根据患者是否行血液透析滤过分组,non-HDF组血清β2微球蛋白均值（51．8±16．9）mg／L,HDF组为（45．4±14．6）mg／L（t=2．138,P=0．034）。多因素线性回归模型显示,血清胆微球蛋白与是否行血液透析滤过（p=-10．015,P=0．000）、残余尿（p=-4．733,P=0．004）、肾小球滤过率（p=-1．897,P=0．002）、球蛋白（B=2．131,P=0．035）存在线性回归关系,透析龄、校正钙磷乘积、尿酸与胆微球蛋白在单因素直线回归模型中存在直线关系,但在多因素回归模型中无线性回归关系。结论本研究发现维持性血液透析患者的血清β2微球蛋白浓度明显升高,透析龄、残余尿量、是否行血液透析滤过治疗与β2微球蛋白存在相关关系,多因素线性分析显示是否行血液透析滤过、残余尿量、肾小球滤过率、球蛋白与β2微球蛋白存在线性回归关系。     

静脉滴注唑来膦酸24小时内对血生化、骨代谢指标的影响

【摘要】〓目的〓观察对绝经后骨质疏松症患者静脉注射唑来膦酸前后血生化、骨代谢指标的影响。方法〓本研究回顾性分析2012~2014年于我科住院部就诊、经骨密度测定证实为骨质疏松症女性患者148人。收集患者滴注唑来膦酸前及滴注24小时后血钙、血磷、血肌酐、骨代谢指标β胶原降解产物(S-CTX),总I型胶原氨基前肽(PINP)。结果〓女性患者年龄为65.98±9.53岁,注射密固达前血钙浓度为2.29±0.10 mmol/L,血磷浓度为1.13±0.15 mmol/L,血肌酐浓度为80.84±13.7 μmol/L,肌酐清除率为53.94±13.96 mL/min,S-CTX浓度为0.32±0.24 ng/mL,PINP浓度为44.98±27.89 ng/mL。注射密固达24小时血钙浓度为2.13±0.14 mmol/L,血磷浓度为1.11±0.15 mmol/L,血肌酐浓度为85.71±12.78 μmol/L,肌酐清除率为50.78±12.98 mL/min,S-CTX浓度为0.176±0.165 ng/mL,PINP浓度为45.60±26.79 ng/mL。血钙较前降低(P<0.05),其中55例患者注射后出现血钙降低,12例患者肌酐清除率低于35 mL/min,但无临床症状。血磷、血肌酐浓度明显降低(P<0.05),但前后浓度均在正常范围内。注射唑来膦酸前后骨吸收标志物S-CTX明显降低(P<0.05),骨形成标志物PINP变化不明显(P=0.65)。说明静脉滴注唑来膦酸能立刻抑制破骨细胞活性,而不能立即影响成骨细胞活性,可引起血钙降低,对血磷、肾功能影响不大。结论〓静脉滴注唑来膦酸能显著抑制骨吸收,安全有效。     

血液透析滤过对尿毒症皮肤瘙痒疗效的观察

目的：观察血液透析滤过与低通量透析对尿毒症皮肤瘙痒的疗效。方法：选择尿毒症皮肤瘙痒患者38例,随机分成观察组（HDF组）及对照组（HD组）,在德国Fresenuise 4008 S透析机上分别行血液透析滤过与低通量透析治疗,每周3次,每次4h,共观察12周;检测血尿素氮（BUN）、肌酐（Cr）、磷、β2微球蛋白（β2-M）;计算尿素清除指数（Kt/V值）;用可视模拟评分法评估瘙痒程度。结果：两组透析后BUN、Cr下降率比较无统计学意义（P〉0.05）,磷的下降率观察组为（52.64±7.82）%,优于对照组（41.20±12.17）%,P〈0.05;β2-M的下降率,观察组为（41.6±10.25）%,优于对照组（1.60±0.94）%,P〈0.05,两组Kt/V比较无统计学意义（P〉0.05）;皮肤瘙痒与治疗前比较两组均有减轻（P〈0.05）,观察组瘙痒程度评分为（2.83±1.07）分,显著低于对照组（5.65±1.71）分,P〈0.05。结论：间断血液透析滤过与低通量透析相比,在保证对小分子毒素充分清除的基础上,增加了对于大、中分子毒素的清除,可以明显减轻尿毒症患者顽固性皮肤瘙痒症状。     

Rebound kinetics of beta2-microglobulin after hemodialysis.

BACKGROUND: Evaluation of beta2-microglobulin (beta2m) removal during hemodialysis using predialysis and immediate postdialysis plasma concentrations is only valid in the absence of postdialysis rebound. Postdialysis rebound of beta2m has not been studied extensively, and its importance in the determination of beta2m clearance is unknown. METHODS: We evaluated the kinetics of urea and beta2m in a crossover study of 10 chronic hemodialysis patients using dialyzers with similar urea mass transfer-area coefficients containing either low-flux cellulose acetate or high-flux cellulose triacetate membranes. Kinetics were examined during and following a 210 minute treatment by measuring plasma concentrations predialysis at regular intervals during therapy and at 0, 2, 10, 20, 30, and 60 minutes postdialysis. Clearances of urea and beta2m were also determined directly from the arterial and venous concentration differences across the dialyzer at 60 minutes after starting dialysis. RESULTS: By design, urea removal was similar for both low-flux and high-flux dialyzers as assessed by the urea reduction ratio and Kt/V. Postdialysis urea rebound was similar for low- and high-flux dialyzers; the rebound in the plasma urea nitrogen concentration (expressed as a percentage of the intradialytic decrease in plasma concentration) was 9.2 +/- 1.9% (mean +/- SEM) at 30 minutes postdialysis and 13.0 +/- 1.4% at 60 minutes postdialysis for a single pool urea Kt/V of 1.16 +/- 0.05. The plasma beta2m concentration increased by 11.1 +/- 3.0% during the treatment using the low-flux dialyzer but decreased by 27.1 +/- 4.0% during the treatment using the high-flux dialyzer. When using the high-flux dialyzer, the rebound of beta2m was 44.8 +/- 21.4% at 30 minute postdialysis and 45.9 +/- 15.9% at 60 minutes postdialysis. The clearance of beta2m for the high-flux dialyzer calculated from predialysis and immediate postdialysis plasma concentrations using a single-compartment model (28.2 +/- 4.4 ml/min) was higher (P < 0.05) than that determined directly across the dialyzer (18.3 +/- 2.0 ml/min). If either the 30- or 60-minute postdialysis plasma beta2m concentration was used instead, the calculated beta2m clearance (16. 5 +/- 4.8 ml/min or 15.6 +/- 2.8 ml/min, respectively) was similar to that determined directly across the dialyzer. CONCLUSIONS: Postdialysis rebound of beta2m when using high-flux dialyzers is substantial; neglecting postdialysis rebound results in an overestimation of beta2m clearance when calculated using a single-compartment model.     

Evaluation of a New Disposable Plate Dialyzer and the Adverse Effect of Recirculation Single Pass Dialysis on Clearance

A new disposable plate dialyzer (PF = Travenol Paraflo 1.0 m² 11.5 μ Cuprophan), is compared with an older device of similar design (GL = Gambro Lundia Nova 1.0 m² 13.5 μ Cuprophan). The ulcrafiltration rate (UF) relative to dialyzer pressure (DP) was greater for GL (3.90 ±. 02 DP ml/min) than for this lot of PF (2.71 ±. 01 DP ml/min). In vivo clearance of urea and creatinine in single pass for PF was 132 ± 5 ml/min and 106 ± 5 ml/min, respectively, at mean blood rate of 200 ml/min. RSP produced significantly lower urea and creatinine clearance (p<.005, <.025). These values were not significantly different from those for GL. Decrease in patient BUN and plasma creatinine during dialysis corroborated the clearance data. SP operation of these plate dialyzers is recommended since the disadvantages of RSP outweigh its advantages.     

Vitamin E-coated membrane dialyzer and beta2-microglobulin removal

This study was designed to test the removal of beta2-microglobulin (beta2M) in a vitamin E-modified membrane. We investigated in vivo the dialyzer (Excebrane, series EE, 1.8 m2) with respect to hydraulic permeability (Kuf), maximum ultrafiltration rate (UF max), sieving coefficient (Sc), and solute clearances in hemodialysis (HD) and in soft hemodiafiltration (HDF). Kuf was 18.4 ml/h/mmHg, UF max was 75 ml/min, and Sc for beta2M was 0.45. Clearance values at 400 ml/min of Qb in HD were 258 ml/min for urea, 201 ml/min for creatinine, and 135 ml/min for phosphate. In soft HDF, clearances were slightly higher. beta2M clearance was 26 ml/min in HD and 43 ml/min in soft HDF. In conclusion, Excebrane (series EE) procures a soft HDF with an amount of substitution fluid in post dilution mode of over 60 ml/min. Remarkable small solute clearances were obtained when the blood flow was raised to 400 ml/min. A significant reduction of beta2M is demonstrated by HDF.     

Severe dialyzer dysfunction undetectable by standard reprocessing validation tests

It is generally accepted that careful monitoring of total cell volume and ultrafiltration rates will ensure adequate function of reprocessed dialyzers. During routine urea kinetic measurements we noted that the percent of patients with clearances less than 200 ml/min increased from 5% to 48% despite adherence to these validation tests. As these patients did not have evidence of recirculation in the vascular access, possible causes of dialyzer dysfunction were investigated. Injection of methylene blue into the dialysate port revealed non-uniform flow of dialysate in dialyzers from patients with markedly reduced clearances. In vitro studies of dialyzers subjected to sequential daily reprocessing, without patient exposure, demonstrated that in vitro clearances declined in one lot but not another. The initial clearances of 218 +/- 4 ml/min fell progressively to 112 +/- 18 (P less than 0.001) after 15 reuses. No effects of reprocessing were found in a different lot (230 +/- 2 vs. 226 +/- 4 ml/min). Soaking the dialyzers from the affected lot in either the disinfectant or dialysate solution caused a decline in the clearances which was less than that of serial reuse. Although the magnitude of the problem of dialyzer malfunction with reuse is unknown, careful attention to dialyzer function is warranted in patients treated with reprocessed dialyzers.     

Effect of Reuse on Dialyzer Efficacy

The effect of reuse on dialyzer efficacy was examined by measuring blood compartment volume and dialyzer mass transfer coefficient (maximum dialyzer clearance) as a function of dialyzer use number. The 102 polysulfone dialyzers tested (F60 and HF80, Fresenius) were reprocessed on Renatron machines using peroxyacetic acid as the dual cleansing and sterilizing agent. Each dialyzer was used an average of 14.4 +/- 5.7SD times and was tested once (twice for 13/102 dialyzers) during a routine dialysis session at an arbitrary use number (7.6 +/- 5.3; range 1 to 24). The parameters tested were found to decrease only marginally with reuse, corresponding to a blood compartment volume loss of approximately 1% (R = 0.04) over a 5-week/15-use period and a decrease in dialyzer mass transfer coefficient of approximately 3% (R = 0.07 and 0.06) over the same period for urea and creatinine, respectively. It was concluded that the loss in dialyzer efficacy is negligible over the average use period of almost 5 weeks per dialyzer.     

Dialyzer-dependent changes in solute and water permeability with bleach reprocessing

The effects of bleach reprocessing on the performance of high-flux dialyzers have not been comprehensively characterized. We compared the effects of automated bleach/formaldehyde reprocessing on solute and hydraulic permeability for cellulose triacetate (CT190) and polysulfone (F80B) dialyzers using an in vitro model. Dialyzers were studied after initial blood exposure (R0) and after 1 (R1), 5 (R5), 10 (R10), and 15 (R15) reuse cycles. Ultrafiltration coefficient (K(uf)), serial clearances, and/or sieving coefficients (SCs) of urea, creatinine, vancomycin, inulin, myoglobin, and albumin were determined. Urea, creatinine, and vancomycin clearances and SCs did not significantly differ from R0 to R15 with either dialyzer. Inulin clearances and SC also did not significantly change from R0 to R15 for the CT190. However, these same values for the F80B significantly increased (P < 0.05). The inulin clearance and SC values for the CT190 dialyzer were significantly higher than those for the F80B at all stages except R15. Myoglobin clearances significantly increased over 15 reuses for both dialyzers (P < 0.01). However, CT190 myoglobin clearances were significantly higher at all stages (R0 = 37.7 +/- 9.7; R15 = 52.5 +/- 8.8 mL/min) than the F80B (R0 = negligible; R15 = 41.3 +/- 16.5 mL/min; P < 0.01). Albumin pre- and postdialysis SCs significantly increased for both dialyzers (P < 0.01). K(uf) for R0 and R15 were 52.3 +/- 3.3 and 52.6 +/- 7.6 mL/h/mm Hg for CT190 (P = not significant) and 48.8 +/- 4.4 and 87.3 +/- 7.0 mL/h/mm Hg for F80B (P < 0.0001). We conclude that bleach reprocessing significantly increases larger solute and hydraulic permeability of high-flux cellulosic and polysulfone dialyzers. This effect is more pronounced for the polysulfone membrane. Until 10 reuses or greater, the removal of solutes greater than 1,500 d is significantly compromised with the polysulfone dialyzer used in this study.     

A Reciprocating, Single-Needle Hemodialyzer with Bidirectional Flow of Sorbent Suspension

Previous theoretical analysis has indicated that adequate mass transfer is possible in a dialyzer with reciprocating membrane motion provided that the dialysate concentration of uremic substances is kept low. Earlier models have utilized a collection of sorbents (charcoal, urease, and a cation exchanger) constrained next to the dialyzer membranes. We have designed a new dialyzer with a sorbent suspension having free access from a reservoir to the spaces between membrane packages. At a treatment rate of 150 ml/min/m², the in vitro creatinine clearance is 75 ml/min/m², which agrees within experimental accuracy with the theoretical prediction. The creatinine clearance, flow resistance, and compliance of the dialyzer are constant during four to six hours of testing. In vivo tests have been performed during urea and creatinine infusion in a normal dog and in a dog with 3/4 nephrectomy. The in vivo creatinine clearance agrees within 10% with the in vitro clearance. Sodium, potassium, calcium, and bicarbonate fluxes are acceptable for patients in renal failure. The new design allows a higher capacity for urea and creatinine, since larger amounts of sorbent may be used.     

Dialyzer reuse: what we know and what we don't know

Despite extensive clinical experience, the effects of different reuse procedures have not been fully evaluated. The available data suggest that the effect of reuse on dialyzer performance depends upon the type of chemicals employed, the membrane type, and the size of the solute whose removal is being assessed. The effect of reuse on urea clearance is essentially defined by the residual cell volume with a total cell volume of > 80% associated with a dialyzer clearance that is within 10% of its original value. The effect of reuse on large solute clearance can be dramatic, with the procedure resulting in substantial changes in the beta2-microglobulin clearance of different dialyzers. Of note is the limited data available regarding the effect of reuse procedures on dialyzers processed more than 20 times.     

Serum Free‐Light Chain Removal by High Cutoff Hemodialysis: Optimizing Removal and Supportive Care

In multiple myeloma the predominant cause of irreversible renal failure is cast nephropathy, secondary to excess κ or λ serum free light chains (FLCs). These molecules are efficiently cleared by hemodialysis (HD) using the Gambro HCO 1100 dialyzer. To optimize the removal of FLCs by this dialyzer we have studied the effect of dialyzers in series, dialyzer change, and hemodiafiltration in 14 patients with multiple myeloma and renal failure. The clearance rates of both κ FLCs and λ FLCs were significantly increased on two dialyzers from 19 (7.3–34)–15.3 (9–28) mL/min to 47 (17–79)–35.5 (20–57) mL/min, respectively. Clearance rates of both FLCs decreased over the course of the dialysis sessions (both P < 0.001). Changing the dialyzer during a HD session increased λ FLC clearance rates (22.5 [6–41] to 37.6 [9–52] mL/min; P < 0.001) and decreased κ FLC clearance rates (39.6 [9–72] to 19 [8–59] mL/min; P < 0.003). Ultrafiltration during HD increased the clearance rates of κ FLCs (R 0.52, P < 0.01) but not λ FLCs (R ?0.25; P < 0.076). Hemodiafiltration increased the clearance rates of both κ (19 [SD 6.8] to 32 [SD 9.8] mL/min) and λ FLCs (15 [SD 7.8] to 20 [SD 7.7] mL/min). Albumin replacement requirements for 8 h of HD increased from 12 g for a single dialyzer to 45 g for two dialyzers in series (P < 0.001). Different protocols are required to optimize the removal of κ and λ FLCs in patients with myeloma and renal failure.