Haemodialysis with low dialysate flow rates: A comparison of high performance membranes and conventional membranes

Summary: We performed experimental studies to examine the effects of low dialysate flow rates on the clearance of small molecular weight substances, a middle molecular weight substance and a low molecular weight protein using a high performance membrane (HPM) and a conventional membrane (CVM). the blood flow rate was 200 mL/min and the diasylate flow rate varied between 300 and 500 mL/min. Clearance of urea and creatinine, representing small molecular weight substances, clearance of vitamin B₁₂ representing a middle molecular weight substance, and clearance of myoglobin, representing a middle molecular weight substance, and clearance of myoglobin, representing a low molecular weight protein were measured. Lowering the dialysate flow rate from 500 to 300 mL/min in the HPM decreased the clearance of urea, creatinine, vitamin B₁₂ and myoglobin by 7.2%, 8.6%, 8.4%, and 2.4%, respectively. Lowering the dialysate flow rate from 500 to 300 mL/min in the CVM decreased the clearance of urea, creatinine, and vitamin B¹² by 8.7%, 10.9%, and 10.4%, respectively. Changes in the clearance of creatinine with reduced dialysate flow rate in the HPM were significantly lower than those in the CVM ( P <0.05). Clearance of urea, creatinine, and vitamin B₁₂ in the HPM at a dialysate flow rate of 300 mL/min were higher than those of in the CVM at a dialysate flow rate of 500 mL/min. These results suggest that dialysate flow rates can be reduced and water can be effectively saved by combining a dialysate flow rate of 300 mL/min with a HPM during water shortages due to natural disasters or climate changes.     

不同钙浓度透析液对维持性血液透析患者钙磷代谢的影响

目的探讨不同钙浓度透析液对维持性血液透析(MHD)患者钙磷代谢紊乱的影响。方法溧水县人民医院157例MHD患者随机分为2组,分别采用钙浓度1.25及1.75mmol/l透析液连续进行3个月透析治疗,分别检测治疗前后血钙及血磷浓度。结果实验结束后,高钙浓度组血钙水平明显升高(P<0.05),血钙×磷浓度水平降低(P<0.05),血磷水平无明显变化(P>0.05)。结论高钙透析液能有效的提高MHD患者血钙浓度,减少钙磷代谢紊乱发生。     

低钙透析对血液透析患者血管结构和心脏功能的影响

目的观察低钙透析对维持性血液透析患者血管结构和心脏功能的影响。方法测定2007年6月至12月在安徽医科大学第三附属医院肾内科血液透析中心30例维持性血液透析（maintenance hemodialysis,MHD）患者,所有患者入组前均使用标准钙1．5mmol／L（dCa^2＋1．5）透析,透析过程平稳。入组后改用低钙1．25mmol／L（dCa^2＋1．25）透析液,余治疗方案不变。入组前及改用低钙透析液6个月后行血生化检查。采用GE ViVid 7型彩色多普勒超声诊断仪检测颈总动脉内膜-中层厚度（intima medial thickness,IMT）、左心室射血分数（left ventricular ejectian fraction,LVEF）,测量舒张早期和舒张晚期最大血流速度。并根据公式计算心脏输出指数,舒张早期和舒张晚期最大血流速度的比值（E／A）等指标。结果在使用dCa^2＋1．25透析液6个月后,患者血清钙值和钙磷乘积与使用dCa^2＋1．5透析液相比明显下降,甲状旁腺激素（parathyroid hormone,PTH）水平明显上升（P〈0．05）,有统计学差异,而其它的血清生化指标的变化无统计学差异。使用低钙透析6个月后,患者颈动脉IMT较使用dCa^2＋1．5透析液相比明显下降,（E／A）比值水平明显上升（P〈0．05）,而左心室射血分数及心脏输出指数在使用dCa^2＋1．25透析液6个月后变化无统计学差异（P〉0．05）。结论低钙透析可改善维持性血液透析患者动脉粥样硬化和动脉顺应性的下降,促进左室舒张功能,并推测其作用可能与纠正钙磷代谢紊乱有关。     

Proteomic Analysis of Peritoneal Dialysate Fluid in Patients with Dialysis-Related Peritonitis

The prognosis of uremia patients on continuous ambulatory peritoneal dialysis (CAPD) is related to frequent peritonitis rate. Frequent peritonitis will lead to peritoneum failure, making CAPD unfeasible. We have performed proteomic profiling of peritoneal dialysis effluent samples from a cross-section of CAPD patients with and without peritonitis in order to identify biomarkers of peritonitis. We performed 2D gel electrophoresis and surface-enhanced laser esorption/ionization time of flight mass spectrometry (SELDI-TOF MS) on peritoneal dialysis effluent from 16 subjects with peritonitis. A genetic algorithm search of principal component space revealed a group of a peak distinguishing peritonitis-positive subjects, with mass/charge (m/z) values of 11,117.4. Our analyses identified the peak at m/z 11,117.4 with an accuracy of 95% for classifying peritonitis. Mass spectrometric analysis of peritonitis PDE samples identified the 11,117.4 protein as β2-microglobulin (B2M). Using an unbiased protein profiling approach, we have validated previously reported findings of B2M as a biomarker associated with CAPD peritonitis. Prospective studies are warranted to establish additional biomarkers that would be predictive of peritoneal dialysis peritonitis. Besides, extending the study to a larger number of patients with subgroup analyses may yield additional information of the peritoneal dialysate proteins in association with dialysis adequacy, residual renal function, nutritional status, and risk of peritoneal infection.     

离子色谱法测定血液透析液中乳酸根的含量

目的：建立离子色谱法测定血液透析液中乳酸根的含量测定方法并进行方法验证,为乳酸盐透析液的质量控制和市场监管提供重要的技术参考。方法用DIONX ICS?1100离子色谱仪进行检测,色谱柱为AS9?HC柱（4 mm×250 mm）,淋洗液为9 mmol／L碳酸钠,流速1 mL／min,电导检测器,外标法定量。结果乳酸根的线性范围为5?03～80?54μg／mL（ r＝0?9999）,定量限为0?1007μg／mL,平均加样回收率为101?4％。结论该方法准确,分析时间短,样品无需前处理,不受样品中其他组分的干扰,可用于血液透析液中乳酸根的含量测定。     

High Glucose Concentrations in Peritoneal Dialysate Are Associated with All-Cause and Cardiovascular Disease Mortality in Continuous Ambulatory Peritoneal Dialysis Patients

♦ Background: The effect of high peritoneal dialysate glucose concentration (PDGC) on all-cause and cardiovascular disease (CVD) mortality in peritoneal dialysis (PD) patients is unclear.♦ Objective: Our study aimed to investigate the effect of high PDGC on all-cause and CVD mortality in continuous ambulatory PD (CAPD) patients.♦ Methods: The study enrolled 716 patients newly initiated on CAPD therapy between January 2006 and December 2010. We allocated the patients to low (<1.56%), medium (≥1.56% to <1.74%), and high (≥1.74%) average PDGC groups according to the tertile of average PDGC in the first 6 months after PD initiation. Cox regression and ordinal logistic regression were used to analyze determinants of mortality and of PDGC use respectively.♦ Results: Mean follow-up in the study cohort was 31 ± 15 months. The all-cause mortality was 4.7 events per 100 patient-years, and the leading cause of death was CVD. Patients with a higher PDGC had significantly higher cumulative rates of all-cause (log-rank p < 0.001) and CVD mortality (log-rank p < 0.001). In Cox regression analysis, high PDGC independently predicted higher all-cause (hazard ratio: 2.63; p = 0.004) and CVD mortality (hazard ratio: 2.78; p = 0.01). Compared with a lower PDGC, a higher PDGC was significantly associated with older age [odds ratio (OR): 1.02; p < 0.001], low residual renal function (OR: 0.91; p < 0.001), and high dialysate-to-plasma ratio of creatinine (OR: 28.61; p < 0.001) in ordinal logistic regression.♦ Conclusions: Higher PDGC is associated with higher allcause and CVD mortality in CAPD patients.     

HT-ED联合UPLC-MS/MS技术分析白头翁皂苷B4的大鼠血浆蛋白结合率

目的:建立血浆中白头翁皂苷B4的分析方法,测定白头翁皂苷B4大鼠血浆蛋白结合率。方法:采用96通道高通量平衡透析系统(HTD 96b)进行透析,利用UPLC-MS/MS测定透析内外液中白头翁皂苷B4的浓度,研究白头翁皂苷B4在大鼠血浆中的血浆蛋白结合率,使用Waters XTerra MS C18色谱柱(2.1 mm×50 mm,5μm),流动相0.1%甲酸水溶液-乙腈梯度洗脱,流速0.7 m L·min~(-1),柱温40℃,进样量5μL。结果:白头翁皂苷B4在5~2 000 ng·L-1线性关系良好,其精密度RSD及准确度均8.0%,重复性RSD9.0%,稳定性的RSD均15%;提取回收率和基质效应均在80%~115%。白头翁皂苷B4在低、中、高(6,12,24 mg·L-1)3个质量浓度下大鼠血浆蛋白结合率分别为(95.32±0.37)%,(94.32±0.63)%,(88.64±0.37)%。结论:白头翁皂苷B4与大鼠血浆具有较强的蛋白结合率,且结合率不具有质量浓度依赖性。     

A study of the clinical and biochemical profile of peritoneal dialysis fluid low in glucose degradation products

♦ Objective: Although peritoneal dialysis (PD) is a widely accepted form of renal replacement therapy, concerns remain regarding the bioincompatible nature of standard PD fluid (PDF). Short-term studies of new biocompatible PDFs low in glucose degradation products (GDPs) reveal divergent results with respect to peritoneal integrity.♦ Methods: We studied 125 patients on maintenance PD who were assigned, by simple randomization, to receive either conventional or low-GDP PDF at PD initiation. Parameters of dialysis adequacy and peritoneal transport of small solutes were determined at initiation and after a period of maintenance PD at the time when serum and overnight effluent dialysate were simultaneously collected and assayed for various cytokines, chemokines, adipokines, and cardiac biomarkers. All patients were further followed prospectively for an average of 15 months from the day of serum and effluent collection to determine patient survival and cardiovascular events.♦ Results: Patients treated with conventional or low-GDP PDF were matched for sex, age, duration of dialysis, dialysis adequacy, and incidence of cardiovascular disease or diabetes. After an average of 2.3 years of PD treatment, the weekly total and peritoneal creatinine clearance, and the total and peritoneal Kt/V were comparable in the groups. However, urine output was higher in patients using low-GDP PDF despite there having been no difference between the groups at PD initiation. Patients using low-GDP PDF also experienced a slower rate of decline of residual glomerular filtration and urine output than did patients on conventional PDF. Compared with serum concentrations, effluent concentrations of tumor necrosis factor α, hepatocyte growth factor, macrophage migration inhibitory factor, interleukins 8 and 6, C-reactive protein, and leptin were found to be higher in both groups of patients after long-term PD, suggesting that the peritoneal cavity was the major source of those mediators. Compared with patients on low-GDP PDF, patients on conventional fluid showed elevated leptin and reduced adiponectin levels in serum and effluent. The effluent concentration of interleukin 8 was significantly lower in patients using low-GDP PDF. The survival rate and incidence of cardiovascular complications did not differ between these groups after maintenance PD for an average of 3.6 years.♦ Conclusions: It appears that low-GDP PDF results in an improvement of local peritoneal homeostasis through a reduction of chronic inflammatory status in the peritoneum.     

血液透析单位透析用水及透析液内毒素含量检测

目的了解某地区血液透析单位透析用水、透析液内毒素污染情况,为透析安全用水提供参考。方法采用动态比浊法对12家透析单位送检样本进行了检测。结果所检测的12家单位透析用水内毒素平均含量为0.083 EU/ml,透析液内毒素平均含量为0.392 EU/ml。不同季节检测的透析用水和透析液内毒素含量存在差异,夏秋季检测的内毒素含量高于冬春季。结论辽西地区医疗机构透析单位透析用水和透析液质量较好,但仍存在少量超标,要求应严格按标准操作规程执行,减少透析液的污染,降低内毒素含量。