The effect of high-flux hemodialysis on renal anemia

BACKGROUND: Anemia is an important predictor of mortality and morbidity in patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD). Erythropoietin (EPO) is an expensive drug, which increases the cost of therapy. In addition, anemia persists in 20-30% of cases despite EPO treatment. In this study, which depended on the idea that the clearance of moderate and high molecular weight erythropoiesis inhibitors leads to an improvement in terms of anemia, we aimed to investigate the effect of high-flux dialysis on anemia and EPO requirement in patients undergoing HD. METHODS: The study included 48 patients with ESRD on chronic HD treatment who could not reach the target hemoglobin (Hb) level, despite treatment with at least 200 IU/kg/week subcutaneous EPO. Patients were randomized into two groups and HD was performed with polysulphone low-flux dialyzer (Fresenius F6 HPS) or polysulphone high-flux dialyzer (Fresenius F60) for 6 months. RESULTS: Although the EPO doses were significantly lower (p<0.001) in the high-flux dialysis group, Hb levels showed a significant increase (p<0.001). In the low-flux dialysis group, Hb levels showed no significant increase, despite the steady increase in EPO doses. In the high-flux group, the reduction of beta2-microglobulin (b2-MG) and phosphorus levels during dialysis was significantly higher when compared to the low-flux group (p<0.001). During the follow-up period, while b2-MG levels decreased significantly in the high-flux group (p<0.05), there was an increase in the low-flux group (p<0.05). Kt/V(urea) values showed no significant difference throughout the study. CONCLUSIONS: Our results suggest that high-flux dialysis use is effective and this can be an alternative method in terms of controlling renal anemia and reducing the cost of therapy. These beneficial effects of high-flux dialysis are probably mediated by the improved clearance of moderate and high molecular weight toxins.     

Pathologic fractures in dialysis-associated amyloidosis

A correlation could be demonstrated between four pathological femoral neck fractures in patients who regularly underwent hemodialysis; cystic bone deposits of beta-2-microglobulin amyloid were also found. The characteristic symptom complex includes painful arthralgia of the shoulder, carpal tunnel syndrome, pain in the hip and recurrent knee effusions. The first step in the diagnostic procedure is to demonstrate cystic defects in skeletal radiographs. Then a biopsy of the cystic bone lesion is needed for histological verification of beta-2-microglobulin. The surgical treatment is total joint replacement or augmented composite osteosynthesis due to poor regeneration capacity in the amyloid bone lesion.     

Convection-enhanced high-flux hemodialysis

Internal filtration contributes to convective clearance in high-flux hemodialysis but its contribution is limited by low pressure gradients. Therefore, a modification using a conventional dialyzer was conceived to enhance internal filtration and backfiltration (BF) rates. The modified dialyzer includes two longitudinal independent regions for blood flow, which were created by redesigning dialyzer caps. Blood pressures remained higher than dialysate pressures in one region and lower in the other region, allowing continuous internal filtration and BF in these respective regions. Modified and conventional dialyzers were compared in terms of pressure gradients and solute clearances. Thus, our experiments involved two groups: the modified dialyzer group and the conventional dialyzer group. A renal failure model was established using a dog weighing 25-30 kg by renal artery and vein ligation. With the exception of the dialyzers, experimental conditions were identical in the two groups. The pressure gradients between blood and dialysate were much higher for the modified dialyzer than for the conventional dialyzer. No significant differences were observed with respect to small solute clearances between the two groups, but mid-range solute clearances were significantly higher in the modified group. More optimization is required before the devised unit can be used clinically. However, the devised unit offers a straightforward means of regulating internal filtration and BF rates.     

Warning of high-flux hemodialysis.

In order to estimate the influence of flux on plasma refilling during hemodialysis (HD), prospective crossover studies were performed in 10 HD patients with low-flux and high-flux dialyzers. Hematocrit was continuously monitored to assess changes in blood volume. In addition, plasma osmolarity and total protein concentration were measured. Intradialytic reductions in body weight (-5 +/- 1 vs -5 +/- 1%) and plasma osmolarity (-5 +/- 1 vs -5 +/- 1%) were similar in both conditions. Although mean blood pressure remained unchanged in either state, the decrease in blood volume was larger in high-flux HD (-13 +/- 2 vs -10 +/- 2%, p<0.05). In spite of greater contraction in blood volume during high-flux HD, total proteins were increased equally between low-flux and high-flux HD (11 +/- 4 vs 11 +/- 4%). Our data that although high-flux HD failed to induce significant drops in blood pressure, it elicited greater magnitude of decreases in blood volume, implicate the judicious application of high-flux HD.     

Effects of high-flux hemodialysis on oxidant stress

BACKGROUND: Neutrophil oxygen radical production is increased in end-stage renal disease (ESRD) patients and it is further enhanced during dialysis with low-flux cellulosic membranes. This increased oxygen radical production may contribute to the protein and lipid oxidation observed in ESRD patients. We tested the hypothesis that high-flux hemodialysis does not increase oxygen radical production and that it is not associated with protein oxidation. METHODS: Neutrophil oxygen radical production was measured during dialysis with high-flux dialyzers containing polysulfone and cellulose triacetate membranes. Free sulfhydryl and carbonyl groups and advanced oxidation protein products were measured to assess plasma protein oxidation. RESULTS: Pre-dialysis, neutrophil oxygen radical production was significantly greater than normal and increased significantly as blood passed through the dialyzer in the first 30 minutes of dialysis. Post-dialysis, however, neutrophil oxygen radical production had decreased and was not different from normal. Pre-dialysis, significant plasma protein oxidation was evident from reduced free sulfhydryl groups, increased carbonyl groups, and increased advanced oxidation protein products. Post-dialysis, plasma protein free sulfhydryl groups had increased to normal levels, while plasma protein carbonyl groups increased slightly, and advanced oxidation protein products remained unchanged. CONCLUSIONS: The results of this study show that neutrophil oxygen radical production normalizes during high-flux dialysis, despite a transient increase early in dialysis. This decrease in oxygen radical production is associated with an improvement in some, but not all, measures of protein oxidation.     

Intraocular pressures during high-flux hemodialysis

The intraocular pressures of 16 patients with end stage renal failure treated with high-flux dialysis were measured before and during a high-flux dialysis treatment. The patients were selected so as not to have glaucoma or history of glaucoma. Intraocular pressures did not change significantly in any patients during or following a high-flux hemodialysis treatment. These data suggest that high-flux hemodialysis does not result in increases in intraocular pressure nor does it precipitate acute glaucoma in well-dialyzed patients undergoing intermittent in-center hemodialysis.     

高通量血液透析与低通量血液透析的透析效果比较

目的 比较高通量血液透析(HFHD)、低通量血液透析(LFHD)对维持性血液透析患者的综合疗效.方法 32例维持性血透患者,随机分为高通量血液透析组(n=16)和低通量血液透析组(n=16),分别每2周透析5次,每次4.5h.分别于首次透析前、透析后取血检测患者血清BUN、Cr、K+、Na+、Ca2+、P3++、β2-MG、Alb及iPTH.同时观察患者的临床症状变化情况.治疗1年后复查并比较上述指标.结果 高通量透析组对iPTH及β2-MG的清除高于低通量血液透析组(p＜0.05).两组Urea、Cr清除率及KT/V值无统计学差异(p＞0.05),透析前后两组K+、Na+、Ca2+、P3+无统计学差异(p＞0.05).高通量透析组患者的临床症状较低通量透析组明显改善,血清白蛋白变化无明显差异(p＞0.05).结论 高通量血液透析对中大分子物质的清除明显优于低通量血液透析,并能改善患者的临床症状,不会引起蛋白质过多的丢失,对小分子物质清除与低通量血液透析具有同样的效果.     

高通量血液透析对维持性血液透析患者营养状况的影响

目的 探讨高通量血液透析（high-flux hemodialysis,HFHD）对维持性血液透析（maintain hemodialysis,MHD）患者营养状况的影响。方法 将MHD的终末期肾脏疾病患者48例,随机分为低通量血液透析（low-flux hemodialysis,LFHD）组和高通量血液透析（high-flux hemodialysis,HFHD）组,每组24例。分别于治疗前和治疗后24周检测血红蛋白（Hb）、血浆白蛋白（Alb）、转铁蛋白（transferrin,TRF）、营养不良-炎症评分（malnutrition inflammation score,MIS）等观察指标。结果 2组治疗前比较,Hb、Alb、TRF、MIS无统计学差异（P〉0．05）;HFHD组治疗后Hb、Alb、TRF较其治疗前增高,MIS较其治疗前降低（P〈0．05）;2组治疗后,HFHD组Hb、Alb、TRF较LF-HD组增高,MIS较LFHD组降低（P〈0．05）。结论 HFHD可有效改善MHD患者的营养状况。     

血液透析患者应用高通量透析的临床疗效观察

目的 比较高通量透析与低通量透析对透析患者的治疗效果.方法 40例维持性血液透析患者采用自身对照的方法,间断接受高通量透析及低通量透析治疗,总计48周.观察治疗过程中临床症状的改善情况,比较2种透析方式单次透析的效果,以及治疗过程中β2微球蛋白、C反应蛋白、白细胞、血清总补体水平的变化趋势.结果 高通量透析期间临床症状缓解明显,且对β2微球蛋白的清除能力明显优于低通量透析,而对于小分子物质的清除能力比较差异无统计学意义(P＞0.05).治疗过程中患者的C反应蛋白有下降趋势,但无统计学意义(P＞0.05),白细胞、血清总补体水平无明显变化.结论 高通量透析能有效地清除β2微球蛋白,从而改善维持性血液透析患者的临床症状及预后.     

血液透析患者应用高通量透析的临床疗效观察

Objective To observe the effect between high-flux dialysis and low-flux dialysis in hemodialysis patients. Methods Forty maintenance hemodialysis patients adopted high-flux dialysis and low-flux dialysis alternatively for 48 weeks by self-control. The symptoms of patients and single-pass effect of each type were observed in the course of therapy. At the same time, β2-microglobulin, C-reactive protein,leucocyte and total complement in blood serum were detected. Results The high-flux dialysis was much better than low-flux dialysis at improving clinical symptoms and the clearance of β2-microglobulin. However,there was no statistical significance in the clearance of micromolecular substances between two kinds of dialysises(P＞0.05). The level of C-reactive protein had a declining trend, however, without statistical significance( P ＜ 0. 05). Leucocyte and total complement in blood serum didn't change obviously. Conclusion The high-flux dialysis can clear β2-microglobulin efficaciously. So it contributes to improve the clinical symptoms and prognosis of maintenance hemodialysis patients.     

Effective removal of methotrexate by high-flux hemodialysis

The purpose of the present study was to examine the clearance of methotrexate (MTX) by high-flux hemodialysis (HD) in pediatric oncology patients. We present three patients who experienced nephrotoxicity and prolonged exposure to toxic MTX concentrations following high-dose infusions during treatment for osteogenic sarcomas. Each patient was successfully treated with high-flux HD, followed by carboxypeptidase G2 (CPDG2) in two cases. Minimal systemic toxicity occurred. We review the literature and discuss guidelines for early and aggressive treatment for this complication of high-dose MTX therapy. Clinically important removal of MTX depends upon prompt initiation of HD after detection of nephrotoxicity and delayed clearance of MTX. Therapy is indicated in cases where compassionate use of CPDG(2) may not be available, or while awaiting its delivery.     

高通量透析对尿毒症患者营养状态的影响

目的 观察高通量透析对尿毒症患者营养状态的总体影响.方法 使用主观综合营养评估得分(SGA)、人体测量指标及血清生化指标等方法对33例患者进行营养评估,观察高通量透析前后患者营养状态的变化.结果 (1)SGA评分:组间差异无统计学意义,均为A级,但营养状态同为A级的患者,有更多的题目选择“A”选项,且选择“明显改善”选项的患者数增多;(2)人体测量指标:高通量透析治疗6个月后,TSF、MAC测量值显著上升(P＜0.05),体重、BMI、MAMC组间差异无统计学意义,营养不良分级发生变化,有更多的以体重为衡量指标的中度营养不良患者转变为轻度营养不良;(3)生化检测指标:高通量透析3个月后,血清CHOL和LDL显著下降(P＜0.05),血清PA、ALB、TG和HDL无显著性变化;高通量透析治疗6个月后,与高通量透析治疗前相比,血清ALB、HDL显著上升,血清CHOL、LDL显著下降(P＜0.05),PA、TG组间差异无统计学意义.结论 高通量血液透析可改善维持性血液透析尿毒症患者的营养状态.     

高通量透析对维持性血液透析患者血压的影响

高通量透析既能清除低分子毒素,也能清除部分中大分子毒素.本研究采用交叉试验设计,旨在比较高通量透析与低通量透析对维持性血液透析(血透)患者血压的影响.     

高通量血透对血浆同型半胱氨酸和超敏C反应蛋白的影响

研究表明高同型半胱氨酸血症与ESRD患者心血管疾病的发生率和病死率有关。尿毒症患者普遍存在微炎症状态。并可能是导致动脉粥样硬化性心脑血管疾病的原因之一。有关高通量透析（HFD）对尿毒症患者血浆同型半胱氨酸（tHCY）及微炎症状态影响的研究不多。本研究旨在通过观察HFD和普通血液透析（HD）对维持性血液透析（MHD）患者血浆LHCY、超敏C反应蛋白（hsCRP）和氨基酸（AAs）浓度的影响，探讨HFD的安全性及临床应用价值。     

Effect of high-flux hemodialysis on quality of life and neuropsychological function in chronic hemodialysis patients.

The objective was to evaluate the effect of high-flux hemodialysis on quality of life, intra- and interdialytic symptoms and neuropsychological function. The study was double-blind single cross-over with random allocation to order of treatment. The patients were stable adult hospital hemodialysis patients. Both the conventional and high-flux membranes were cellulose acetate, the dialysate was bicarbonate, and dialysate sodium was held constant. The high-flux membrane had an ultrafiltration rate of 15 ml/h/mm Hg transmembrane pressure, a B12 clearance of 88 ml/min and a beta 2-microglobulin clearance of 11.4 ml/min. The values of the conventional membrane were 3.5-5.0, 34-45 and negligible. Each treatment period was 4 months. Twenty-two patients completed both phases of the cross-over. The KT/V value was higher during high-flux than conventional treatment; 1.42 versus 1.27(p < 0.05). There were no differences between high-flux and conventional treatment with respect to quality of life. Symptoms during dialysis were less severe during high-flux than conventional treatment for 12/14 items. Only 3 items reached statistical significance (0.05 > p > 0.01) and none were clinically significant. Symptoms between dialyses were less severe during high-flux than conventional treatment for 18/20 items. No single item had a statistically significant improvement but 3 had clinically important improvement. Among the 23 neuropsychological variables, none demonstrated statistically significant changes.     

Successful treatment of life-threatening pentoxifylline intoxication by high-flux hemodialysis

High-flux hemodialysis is the method of choice for the treatment of many life threatening intoxications. Reports on intoxication with pentoxifylline are rare, and although pharmacokinetic properties of the drug suggest a potential role for hemodialysis, there are no published reports on extracorporeal treatment attempts. We report the first case of successful treatment of potentially life-threatening pentoxifylline intoxication by high-flux hemodialysis. Based on this single case, dialysis should be considered, especially in anuric patients with pentoxifylline intoxication.