High-volume Hemodiafiltration Research Articles

The Donnan equilibrium is still valid in high-volume HDF.

Clinical studies have shown that hemodiafiltration reduces morbidity and mortality of dialysis patients compared to hemodialysis alone. This is attributed to its superior middle molecule clearance compared to standard hemodialysis. However, doubts arose as to whether a high convective flux through the dialyzer membrane has an influence on the equilibrium concentration of small ions, especially that of sodium. Due to the presence of negatively charged impermeable proteins on the blood side, the Gibbs-Donnan effect leads to an asymmetric distribution of membrane permeable ions on both sides of the membrane. In thermodynamic equilibrium, the concentrations of those ions can easily be calculated. However, the convective fluid flow leads to deviations from thermodynamic equilibrium. In this article, the effect of a convective flow on the ion distribution across a semipermeable membrane is analyzed in a theoretical model. Starting from the extended Nernst-Planck equation, including diffusive, convective, and electrostatic effects, a set of differential equations is derived. An approximate solution for flow speeds up to 0.1 ms-1 as well as a numerical solution are given. The results show that in any practical dialysis setting the convective flow has negligible influence on the electrolyte concentrations.

Dialysis modality and quality of life: more answers yet more questions

Persons with end-stage kidney disease treated with dialysis experience distressing reductions in quality of life and increased mortality. Few large, randomized trials in nephrology have reported on health-related quality of life. Rose etal. report beneficial effects of high-volume hemodiafiltration versus high-flux hemodialysis on secondary end points of health-related quality of life in the CONVINCE trial (Comparison of High Dose Hemodiafiltration with High Flux Hemodialysis Trial). These results raise questions regarding hemodiafiltration as a potential modality to preserve health-related quality of life in end-stage kidney disease.

Randomized trial demonstrating no translocation of intact intestinal bacteria during hemodialysis or hemodiafiltration

IntroductionThe low incidence of intradialytic hypotension (IDH) in high-volume (HV) hemodiafiltration (HDF) may help maintaining gut perfusion during treatment. Preservation of gut endothelial integrity would limit or prevent bacterial translocation and subsequent systemic inflammation, which may contribute to the low mortality rate in HV-HDF. MethodsForty patients were cross-over randomized to S-HD, cool HD (C-HD) and HDF (low-volume [LV] and HV, convection volumes 15 L resp. ≥23 L/session), each for 2 weeks. Quantitative assessment of microbial DNA (mDNA) in blood was performed before and after dialysis by 16S-23S interspace profiling after DNA isolation. The intradialytic acute phase response (APR) was evaluated by high-sensitivity CRP (hs-CRP), IL-6 receptor (IL-6R), soluble CD14 (sCD14) and vascular-cell-adhesion molecule-1 (VCAM-1). Differences between modalities were primary objectives. ResultsMDNA was absent in all samples. IL-6R, sCD14, and VCAM-1 increased equally in all modalities (median increase resp.: 12.5%, 14.0%, 14.8%, P<0.05). Hs-CRP increased only in C-HD and HV-HDF (median increase: 12.6%, P<0.05). After correction for hemoconcentration, most APR-markers decreased (median: sCD14 -11.3% and VCAM-1 -14.4% in all modalities; IL-6R -13.4% in C-HD, LV- and HV-HDF; P<0.05). Hs-CRP only decreased in C-HD (-13.5%, P=0.004). Conclusions1) Circulating mDNA could not be demonstrated; 2) while in the crude analysis a similar APR was noted in all modalities, individual markers remained stable or declined after correction for hemoconcentration; 3) as neither bacterial translocation nor an APR was observed in either modality, it is highly unlikely that the superior survival of HV-HDF is explained by superior preservation of gut integrity.

5-Year Mortality Outcomes of High-Volume Hemodiafiltration in Mexico: Insights from Real-World Data

5-Year Mortality Outcomes of High-Volume Hemodiafiltration in Mexico: Insights from Real-World Data

Switching from acetate to citrate dialysate in a central concentrate delivery system for high-volume online hemodiafiltration: a retrospective cohort study

Interest in citrate-based dialysate (Cit-D) is growing due to its benefits, including anticoagulation and dialysis efficacy. However, research on safety and efficiency of Cit-D in high-volume hemodiafiltration (HDF) via central concentrate delivery system (CCDS) is scarce. This study aimed to investigate the safety and efficacy of Cit-D when switching from acetate-based dialysate (Acet-D) in high-volume HDF via CCDS. This is a retrospective analysis of 28 patients who underwent post-dilution online HDF via CCDS, who switched from Acet-D to Cit-D. The study period was divided into 3 periods for analysis: 12 weeks using Acet-D (AD period), the first 12 weeks using Cit-D (CD-1 period), and the second 12 weeks using Cit-D (CD-2 period). We collected the laboratory, dialysis, and safety parameters in each period from electrical medical records. After switching from Acet-D to Cit-D, heparin dosage decreased by 17%, whereas the incidence of complications did not increase. Kt/VBUN and urea reduction ratio increased by 4.6% and 2.1%, respectively. Pre-dialysis beta2-microglobulin concentration decreased after using Cit-D. The corrected calcium levels decreased in the CD-1 period compared to the AD period, but in CD-2, they subsequently increased to levels similar to those observed during the AD period. Symptomatic hypocalcemia did not occur, and there was no significant difference in the incidence of hyperparathyroidism. Endotoxin levels and the bacterial culture of ultrapure dialysate were unremarkable throughout all periods. These results might suggest that Cit-D could potentially offer advantages over Acet-D, such as reducing the heparin dose and increasing dialysis efficiency, in patients undergoing high-volume HDF using CCDS.

Advancing high-volume hemodiafiltration: from concept to CONVINCE

Advancing high-volume hemodiafiltration: from concept to CONVINCE

Controversy on the CONVINCE study findings: the PRO take.

The CONVINCE study, recently published in the New England Journal of Medicine, reveals a groundbreaking 23% reduction in the relative risk of all-cause mortality among end-stage kidney patients undergoing high convective volume hemodiafiltration. This significant finding challenges the conventional use of high-flux hemodialysis and offers hope for improving outcomes in chronic kidney disease patients. While some controversies surround the study's findings, including concerns about generalizability and the causes of death, it is essential to acknowledge the study's design and its main outcomes. The CONVINCE study, part of the HORIZON 2020 project, enrolled 1360 patients and demonstrated the superiority of hemodiafiltration in reducing all-cause mortality overall, as well as in specific patient subgroups (elderly, short vintage, non-diabetic, and those without cardiac issues). Interestingly, it was shown that hemodiafiltration had a protective effect against infection, including COVID-19. Future research will address sustainability, dose scaling effects, identification of subgroups especially likely to benefit and cost-effectiveness. However, for now, the findings strongly support a broader adoption of hemodiafiltration in renal replacement therapy, marking a significant advancement in the field.

#672 Intradialytic hypotension and adverse symptoms are not related

Abstract Background and Aims Intradialytic hypotension (IDH) is the most common side-effect of intermittent hemodialysis (HD). Yet, its definition lacks consensus about the magnitude of blood pressure (BP) drops, occurrence of adverse symptoms (AS) and/or interventions. Generally, BP is measured twice/hour, while additional readings are carried out when AS arise. Consequently, AS became a prerequisite for the diagnosis of IDH, both in the National Kidney Disease Outcomes Quality Initiative (KDOQI) and in the European Best Practice Guideline (EBPG). Yet, a large study on the associations between 8 IDH definitions and mortality, showed that an absolute nadir systolic blood pressure (SBP) &amp;lt;90 mmHg or &amp;lt;100 mmHg (with a pre-dialysis SBP &amp;lt; 160 mmHg or SBP ≥160 mmHg resp.) is most strongly associated with mortality. Neither AS nor interventions were related to outcome. Due to the absence of reliable studies, however, it is still unclear whether IDH and AS are related. Therefore, 1) the occurrence of (a)symptomatic IDH was evaluated according to the nadir-based definition; 2) relations between real-time AS and IDH were explored; 3) associations between IDH-susceptibility and physical intradialytic patient-reported outcome measures (PID-PROMS) were analysed. Methods Forty HD patients were cross-over randomized to standard HD (S-HD), cool HD (C-HD), low-(LV) and high-volume (HV) hemodiafiltration (HDF), each for two weeks. Every second week, BP was measured every 15 minutes during treatment. While AS were monitored real-time, PID-PROMS were documented after each modality with a modified dialysis symptom index [mDSI] questionnaire. The occurrence of symptomatic and asymptomatic IDH, defined as a SBP &amp;lt; 90 or 100 mmHg (depending on the pre-dialysis SBP), was evaluated. For each presentation of AS, we assessed its association with blood pressure by examining concurrent IDH using both the KDOQI/EBPG definitions and the nadir-based definition (Fig. 2). Patients were stratified into tertiles of IDH (IDH-prone, IDH-intermediate and IDH-resistant). The frequency and severity of discrete symptoms, recovery time and total symptom-burden were compared using logistic regression models and Kruskal-Willis tests. Results In 458 sessions, 222 IDH-episodes occurred of which 98% were asymptomatic. While nursing records revealed 24 real-time AS, 54% was BP-related and 17% fulfilled the nadir-based criteria, leaving 46% of AS unrelated to IDH (Fig. 2). IDH-prone patients experienced headaches more frequently (p = 0.01), and perceived dizziness (p = 0.05) and shivering (p &amp;lt; 0.01) more severely. No associations were found between IDH-susceptibility and symptom-burden, recovery time, or other discrete side-effects. Conclusions 1) Most IDH-episodes are asymptomatic; 2) Conversely, 46% of AS occur without IDH and (3) PID-PROMS are completely independent of IDH-susceptibility. 4) Symptom-based definitions severely underestimate IDH, when compared to a nadir-based IDH definition.

#1094 Hemodiafiltration improves solute clearance without increasing water consumption: an educational bench model for the dialysis ward

Abstract Background and Aims Recently, the positive results of the CONVICE trial have raised the question whether the improved outcome of postdilution high volume HDF (oHDF-p) compared to high flux HD (hfHD) requires increased water consumption. From mathematical modelling it can be shown that oHDF-p always leads to higher low molecular clearance than hfHD at equal total dialysate consumption Qd_tot = Qd_dial + Qs (Qd_dial: dialysate flow through the dialyzer, Qs: substitution flow). This has also been shown in a clinical trial (Mesic et al, HDI 15, p. 522-529). However, mathematical modelling might not be intuitive for everyone, and clinical trials are always influenced by multiple confounders. To add a more intuitive way of reasoning, a simple educational bench model was designed based only on equipment easily available in a standard dialysis clinic which allows to compare dialysis efficiencies based on the urea concentrations as surrogate parameter. Since the fundamental task of dialysis is to cleanse blood from uremic solutes, the treatment modality which at equal resource utilization reduces solute concentration most is the more efficient one! Method Dialysis treatments were simulated in single pass setup using a Fresenius 5008S machine (Fig. 1). Blood inlet was simulated as a fixed urea concentration of 170 mg/dL in dialysate from a 110 L reservoir “cbi”. Treatment parameters were set such that they correspond to effective values in in-vivo treatments: As the mass transfer coefficient is always much higher in vitro with water than in vivo with blood, a small high-flux dialyzer (Fresenius FX40) was used. Blood flow Qb was set to 300 mL/min, corresponding to the in vivo blood water flow for Qb_set ∼ 350 mL/min. Alternating experiments in oHDF-p and hfHD were carried out in triplicate with Qd_tot=400 mL/min and 300 mL/min. This resulted in the settings HDF400, HD400, HDF300 and HD300 (cf. Fig. 1). Qs was set to 100 ml/min in oHDF-p. In each setting the fluid from blood and dialysate outlet were collected (recipients “cbo” and “cdo”, resp.) for 8 min. To be independent of the machine accuracy of set flow rates, sample volumes were measured by weighing, and effective flow rates of blood Qb_eff and total dialysate Qd_tot_eff were calculated. Samples were taken into monovettes from “cbi”, “cbo” and “cdo”. Urea concentrations cbi, cbo and cdo were determined by sending the samples to two commercial clinical labs who delivered consistent results. Blood and dialysate side urea clearances were calculated as KUB= Qb_eff*(cbi-cbo)/cbi and KUD=Qd_tot_eff*cdo/cbi. Results The table in Fig. 1 includes the measure values of Qb_eff and Qd_tot_eff for each setting. Blood and dialysate outlet concentrations (cbo and cdo, resp.) and calculated blood and dialysate side clearances are shown in Fig. 2. Lab results in repeated settings were highly reproducible with a SD &amp;lt; 2 mg/dL. Switching from hfHD to oHDF-p at equal Qd_tot always decreased cbo, corresponding to a higher clearance in oHDF-p. Reducing total dialysate flow from 400 to 300 ml/min caused a slight decrease in clearance in both modalities. KUB and KUD were in good agreement, showing that urea mass balance was well controlled in the experiment. Conclusion The educational bench model demonstrates the superior low molecular clearance of oHDF-p compared to hfHD at equal Qd_tot, reflected by lower urea cbo values in oHDF-p. Although the clinical outcome advantage of oHDF-p is rather related to middle molecular clearance, the model shows that the improved treatment quality of oHDF-p can be provided with no extra resource utilization compared to hfHD, and that dialysis adequacy as measured by urea clearance is even increased despite of the fact that a part of Qd_tot is deviated as substitution fluid. As moderately reducing Qd_tot in many cases only results in acceptable clearance reductions, the automated adjustment of both dialysate and substitution flow rates for oHDF-p could improve patient outcome at even reduced resource utilization.

#1277 Comparing advanced glycation end products removal in super high-flux hemodialysis versus high-volume hemodiafiltration: a randomized, crossover study

Abstract Background and Aims Expanded hemodialysis using super high-flux membrane, is a promising therapy for effectively clearing middle molecule uremic toxins. However, its impact on advanced glycation end products (AGEs), which is related to an increase in cardiovascular mortality [1], remains inconclusive. Previous studies demonstrated that AGEs increased over time in patients treated with high-flux hemodialysis (HD) [2, 3] while remaining stabilized in online hemodiafiltration (ol-HDF) [3]. This study aims to compare the longitudinal tissue AGEs measured by skin autofluorescence (SAF) between super high-flux hemodialysis (SHF-HD) and high-volume post-dilution ol-HDF. Method In this open-label prospective cross-over 24-week trial, twenty-two prevalent HD patients were randomly assigned to undergone two sequences of 24-week treatment periods: SHF-HD followed by high-volume postdilution ol-HDF or vice versa, with a 4-week wash-out period with high-flux HD between. SAF was measured at baseline and 24 weeks. Midweek pre-HD measurements of beta-2 microglobulin (B2M), serum albumin, normalized protein catabolic rate (NPCR) and Kt/V were obtained every 8 weeks. The amount of dialysate albumin was collected by continuous sampling of spent dialysate method and determined by immunoturbidimetric assay Results Seventeen out of twenty-two patients completed the study. At baseline, SAF levels (3.88 ± 0.14 vs 3.99 ± 0.14 AU, p = 0.463) and pre-HD B2M (22.66 ± 1.41 vs 21.09 ± 1.41 mg/L, p = 0.228) were similar between the SHF-HD and ol-HDF groups. After 24 weeks, SAF levels showed no significant change in SHF-HD (from 3.88 ± 0.14 to 3.91 ± 0.14 AU, p = 0.846) and ol-HDF (from 3.99 ± 0.14 to 3.95 ± 0.14 AU, p = 0.796), with a mean difference of change 0.06 (95% CI −0.34, 0.47, p = 0.75). Similarly, mid-week pre-HD serum B2M at 24 weeks exhibited no significant change in the SHF-HD group (22.66 ± 1.41 to 22.18 ± 1.47 mg/L, p = 0.722) and the ol-HDF group (21.09 ± 1.41 to 21.83 ± 1.45 mg/L, p = 0.577), with a mean difference of change −1.22 (95% CI −4.94, 2.49, p = 0.519). The spKt/V urea did not exhibit any notable differences. Furthermore, pre-HD levels of all small uremic toxins after the 24-week periods did not differ between both groups. Nutritional status measured by serum albumin and NPCR were comparable despite higher dialysate albumin loss in postdilution ol-HDF group (0.82 ± 0.04 vs 1.92 ± 0.12 g, p &amp;lt; 0.001 in SHF-HD and ol-HDF, respectively) Conclusion After 24 weeks of treatment, SHF-HD demonstrated levels of AGEs, pre-HD serum B2M, and serum albumin comparable to high-volume ol-HDF. If high-volume postdilution ol-HDF is not feasible, SHF-HD may serve as a valuable alternative treatment for stabilizing AGEs in chronic hemodialysis patients.

#2812 Continuous blood pressure monitoring with a finger cuff is unreliable in chronic hemodialysis patients

Abstract Background and Aims Intradialytic hypotension (IDH) is the most common complication of hemodialysis (HD), which is often related to ultrafiltration. Due to the high prevalence of cardiovascular disease (CVD), compensatory mechanisms often fail. In clinical practice, BP is measured 2x/hour, while additional readings are only performed when symptoms arise. However, since IDH defined by a nadir systolic BP (SBP)&amp;lt;90 mmHg or &amp;lt;100 mmHg (depending on pre-dialysis SBP), regardless of symptoms, is most strongly associated with mortality, current BP measurement frequency may severely underestimate the true incidence of IDH. Continuous BP-monitoring may offer a solution to this issue. The Clearsight device (CSD) is a non-invasive continuous BP-monitoring system that measures arterial pressure and waveforms through a finger cuff by photoplethysmography. Yet, a compromised peripheral circulation may hamper its reliability in HD patients. This study aims to assess the agreement between intradialytic CSD-monitoring and standard oscillometric brachial arterial pressure (oBAP) assessment. Methods 40 Chronic HD patients were cross-over randomized to 4 modalities, each for 2 weeks: [standard HD (S-HD), cool HD (C-HD), low volume hemodiafiltration (LV-HDF) and high-volume HDF (HV-HDF)]. During one session of each second week, BP and heart rate (HR) were continuously recorded with the CSD (BMEYE/Edwards Lifesciences) and every 15 minutes with a brachial arterial cuff (contralateral of the fistula or graft, if applicable). Simultaneous measurements of SBP, diastolic BP (DBP) and HR were compared with descriptive statistics (mean difference [bias, BAP minus CSD], standard deviation (SD) and range) and Bland-Altman analysis. Bias was defined as the mean difference between oBAP and CSD, and 95% limits of agreement (LA) as the mean difference ±1.96 SD. Post-hoc, patients were stratified into tertiles of unexplained missing CSD-readings, to explore whether specific patient characteristics explain failed readings. Results 75% of patients was male, with a mean age 69.7 (±13.5 years) and median dialysis vintage 3.0 years (IQR 1.0-5.8). Diabetes mellitus and CVD were present in 48% and 73%, resp. Of the 2720 paired BP-measurements, 42% CSD and 6% of oBAP-readings were missing, leaving 36% of absent CSD-readings unexplained. Bland-Altman analysis, comparing oBAP and CSD-measurements, revealed a mean bias ± LA of 13.3 ± 44.5 mmHg for SBP, a mean bias ± LA of 13.3 ± 25.5 for DBP, and a mean bias ± LA of −0.03 ± 22.9 for HR. Surprisingly, the group with a high (&amp;gt;38%) proportion of unexplained missing CSD-values was significantly younger compared to the low (&amp;lt;21%) and intermediate group (21-38%) (p = 0.015), whereas no significant differences were observed with respect to dialysis vintage, diabetes mellitus or CVD. Conclusions 1) Compared to the oBAP method, finger cuff-monitoring shows poor precision and accuracy in BP-measurements, but good accuracy and poor precision in HR-readings; 2) 1/3 of readings failed for unknown reasons. Thus, CSD-monitoring is unsuitable for intradialytic hemodynamic monitoring in chronic HD patients.

Does online high-volume hemodiafiltration offer greater efficiency and sustainability compared with high-flux hemodialysis? A detailed simulation analysis anchored in real-world data.

Recent findings, including the CONVINCE (comparison of high-dose HDF with high-flux HD) study report, suggest the superiority of high-volume hemodiafiltration (HDF) over high-flux hemodialysis (HD) in improving patients' outcomes. Despite positive patient outcomes, concerns have arisen about the potential negative environmental impact of high-volume HDF, as it may lead to increased water and dialysis fluid consumption and higher waste production. In this manuscript, we address the environmental impact of high-volume HDF, focusing on three key factors: water treatment consumption, dialysis fluid consumption, and solute efficiency markers of HD and HDF. By optimizing HDF prescription through adjustments in operational capabilities, while keeping a high blood flow (i.e.,>350ml/min) such as reducing the QD/QB ratio to 1.2 rather than 1.4 or 1.5 and incorporating automated ultrafiltration and substitution control, we demonstrate that HDF delivers a higher dialysis dose for small- and middle-molecule uremic compounds with the same dialysis fluid consumption, and at equal dialysis doses dialysis fluid consumption is reduced. This finding is supported by real-world data from 26031 patients who underwent high-volume postdilution HDF at a reduced dialysis flow (430mL/min) and achieved an effective OCMKt/V of 1.70 (where "OCM" stands for online clearance measurement, "K" represents effective dialysis clearance and "V" denotes total body water measured by multifrequency bioimpedance). In addition, simulation modeling calculations, using blood extraction coefficient, dialysate saturation coefficient and solute clearances with urea (small molecular weight) and β2-microglobulin (middle molecular weight), consistently show the superiority of postdilution HDF to HD. This holds true even with a significant reduction in dialysis flow down to 430mL/min, reflecting QD/QB ratio of 1.2. Postdilution HDF generates high ultrafiltrate flow (up to 35% of blood flow), delivering saturated ultrafiltrate to the lower solute concentration containing effluent dialysate, thus enhancing solute clearance which opens the way to reduce the dialysis flow. In conclusion, our analysis, combining simulation and real-world data, suggests that postdilution HDF could be a more environmentally friendly treatment option compared with conventional HD. Additionally, automated user-friendly functions that minimize dialysis fluid use can further strengthen this environmental benefit while enhancing efficiency.

Intradialytic cardiovascular injury is lowest in high-volume haemodiafiltration: a randomized cross-over trial in four intermittent dialysis strategies.

Intradialytic hypotension (IDH) and subsequent tissue damage may contribute to the poor outcome of chronic haemodialysis (HD) patients. While the IDH-incidence is lower in high-volume haemodiafiltration (HV-HDF) than in standard HD (S-HD), survival is better in HV-HDF. Tissue injury, as measured by extracellular vesicle (EV)-release, was compared between four modalities. Forty chronic patients were cross-over randomized to S-HD, cool-HD (C-HD), low-volume HDF (LV-HDF), and HV-HDF. Blood pressure was recorded every 15 minutes. EVs from circulating blood-cell-elements (bio-incompatibility-related) and cardiovascular (CV) tissues (CV-related), were measured before and after dialysis. The influence of modalities and IDH on the rate of change of EVs was assessed. Both crude and haemoconcentration-adjusted analyses were performed. Leukocyte and erythrocyte-derived EVs increased in all modalities. Platelet-derived EVs increased more in LV-HDF and HV-HDF (68.4 respectively 56.1×106/ml) than in S-HD (27.5×106/ml), P values for interaction were <.01 respectively .06. Endothelial-derived CD144+ (2.3×106/ml in HV-HDF and 9.8×106/ml in S-HD) and cardiomyocyte-derived Connexin-43+ (12.0 respectively 31.9×106/ml) EVs increased less in HV-HDF than in S-HD (P for interaction .03 respectively .06). Correction for haemoconcentration attenuated all changes, although the increase in platelet-derived EVs remained significant in LV-HDF and HV-HDF, and CD144+ and Connexin-43+ EVs increased most in S-HD. EV release was similar in patients with varying IDH susceptibility and in sessions with and without IDH. Most EVs increase during HD and HDF. Regarding platelet-derived EVs, HDF appears less biocompatible than HD. Considering CV-related EVs, tissue injury seems less pronounced in HV-HDF. The finding that EV release is IDH-independent needs confirmation.

Опыт применения высокопроницаемых мембран диализаторов в лечении политравмы

Acute kidney injury in polytrauma is a common and serious complication that significantly worsens the prognosis. Objective: to evaluate the effect of hemodialysis (HD) with high-permeability membranes on the reduction of myoglobin in polytrauma and rhabdomyolysis complicated by acute kidney injury in comparison with plasmapheresis and high-volume hemodiafiltration. Methods: 18 patients with increased creatine phosphokinase (CPK) above 5000 U/E and myoglobin above 1000 ng/ml, stage 3 AKI. The severity of polytrauma was assessed according to the AIS–ISS criteria. The patients were male, from 27 to 47 years old. Results: The average decrease in myoglobin during highflow extended hemodialysis for 2 hours was 31.25% Conclusion: High-flow extended hemodialysis is an alternative method that removes myoglobin and is superior to hemodiafiltration and plasmapheresis in its removal.

Nephrology: what's new in 2023

Molecules such as sparsentan and budesonide look promising to treat proteinuric IGA nephropathy. SLGT2 inhibitors have a prominent place in nephroprotection and could be used in the treatment of acute kidney injury due to heart failure as well. High volume hemodiafiltration compared to hemodialysis improves survival in dialysis patients. Lessening dialysate temperature does not improve hemodynamic stability during the dialysis session. Sodium bicarbonate does not seem to protect renal function in renal transplant patients. SGLT2 inhibitors may have a beneficial effect in these patients in terms of nephroprotection.

The Evolution of Hemodialysis in Chile: Is Hemodiafiltration the Next Step?

Hemodialysis began in Chile during the latter half of the 20th century, primarily targeting individuals with acute renal failure. With time, dialysis facilities emerged across diverse regions of the nation, covering hospitals and private centers. This expansion widened dialysis access to chronic patients, culminating in universal coverage through the AUGE plan. Ongoing technological improvements and the integration of pharmaceutical interventions for chronic kidney disease-related complications have notably enhanced survival rates. Nonetheless, dialysis recipients continue to confront significantly elevated mortality risks in comparison to the general population. Despite advancements, complications linked to dialysis persist, significantly affecting patients' overall quality of life. Heightened rates of hospitalization and mortality are, in part, ascribed to the inherent technical limitations of hemodialysis in efficiently clearing uremic toxins. Therefore, superior purification modalities such as high-volume hemodiafiltration need to be progressively adopted to effectively address the persistent clinical needs in the care of dialysis patients within the Chilean context.

Use of a Novel Machine Learning Tool (“DoWhy”) to Compare Mortality Risk Between High Volume Hemodiafiltration (HV-HDF) and Hemodialysis (HD) Patients in a Large Cohort from Latin America (LA)

Use of a Novel Machine Learning Tool (“DoWhy”) to Compare Mortality Risk Between High Volume Hemodiafiltration (HV-HDF) and Hemodialysis (HD) Patients in a Large Cohort from Latin America (LA)

Unveiling the Clinical Benefits of High-Volume Hemodiafiltration: Optimizing the Removal of Medium-Weight Uremic Toxins and Beyond.

Dialysis treatment has improved the survival of patients with kidney failure. However, the hospitalization and mortality rates remain alarmingly high, primarily due to incomplete uremic toxin elimination. High-volume hemodiafiltration (HDF) has emerged as a promising approach that significantly improves patient outcomes by effectively eliminating medium and large uremic toxins, which explains its increasing adoption, particularly in Europe and Japan. Interest in this therapy has grown following the findings of the recently published CONVINCE study, as well as the need to understand the mechanisms behind the benefits. This comprehensive review aims to enhance the scientific understanding by explaining the underlying physiological mechanisms that contribute to the positive effects of HDF in terms of short-term benefits, like hemodynamic tolerance and cardiovascular disease. Additionally, it explores the rationale behind the medium-term clinical benefits, including phosphorus removal, the modulation of inflammation and oxidative stress, anemia management, immune response modulation, nutritional effects, the mitigation of bone disorders, neuropathy relief, and amyloidosis reduction. This review also analyzes the impact of HDF on patient-reported outcomes and mortality. Considering the importance of applying personalized uremic toxin removal strategies tailored to the unique needs of each patient, high-volume HDF appears to be the most effective treatment to date for patients with renal failure. This justifies the need to prioritize its application in clinical practice, initially focusing on the groups with the greatest potential benefits and subsequently extending its use to a larger number of patients.

Comparative Clinical Performances of Tunneled Central Venous Catheters versus Arterio-Venous Accesses in Patients Receiving High-Volume Hemodiafiltration: The Case for High-Flow DualCath, a Tunneled Two-Single-Lumen Silicone Catheter.

in this retrospective single-center study, we aimed to report on the clinical performances achieved with high-flow tunneled CVCs (DualCath or DCath) and compared them with arteriovenous accesses (AVAs, e.g., AV fistula, AV graft, and Thomas Shunt) in a hospital-based dialysis unit. Sixty-eight stage 5 chronic kidney disease dialysis-dependent patients (CKD5D) receiving high volume hemodiafiltration were followed-up with for 30 months. The study consisted of two phases: baseline cross-sectional and longitudinal follow-ups of key performance indicators. Clinical performances consisting of effective blood flow and blood volume, recirculation, urea and ionic Kt/V, total Kt, ultrafiltration volume, and percent reduction in β2-M were measured monthly as part of quality control in our unit. At baseline, the effective blood flow using a DCath was close to 400 mL/min, similar to an AVA. Recirculation with a DCath (7%, 6-13%) was higher than with an AVA. The diffusive dialysis dose delivered with a DCath (spKt and eKt/V) and convective dialysis dose achieved with a DCath were slightly lower than those achieved with AVAs, but they were still much higher than is recommended by guidelines. The percent reduction in β2-M achieved with a DCath was also 4 to 10% lower than that achieved with an AVA. On longitudinal follow-up, the main clinical performance indicators of DCaths (total Kt and total ultrafiltration volume, L/session) were maintained as very stable over time and close to those achieved with AVAs. As shown in this study, high-flow DualCath tunneled two-single-lumen silicone catheters may be used to deliver high volume hemodiafiltration in a reliable and consistent manner without compromising clinical performance. These results relied on the specific design of the two silicone cannulas and the strict adherence to best catheter practices.

Comparison of the medium cutoff dialyzer and postdilution hemodiafiltration on the removal of small and middle molecule uremic toxins.

The medium cutoff (MCO) dialyzer increases the removal of several middle molecules more effectively than high-flux hemodialysis (HD). However, comparative data addressing the efficacy and safety of MCO dialyzers vs. postdilution hemodiafiltration (HDF) in Korean patients are lacking. Nine patients with chronic HD were included in this pre-post study. Patients underwent HD with an MCO dialyzer for 4 weeks, followed by a 2-week washout period using a high-flux dialyzer to minimize carryover effects, and then turned over to postdilution HDF for 4 weeks. Reduction ratios and differences in the uremic toxins before and after dialysis were calculated from the MCO dialysis, postdilution HDF, and high-flux HD. In the in vitro study, EA.hy926 cells were incubated with dialyzed serum. Compared to postdilution HDF, the MCO dialyzer achieved significantly higher reduction ratios for larger middle molecules (myoglobin, kappa free light chain [κFLC], and lambda FLC [λFLC]). Similarly, the differences in myoglobin, κFLC, and λFLC concentrations before and after the last dialysis session were significantly greater in MCO dialysis than in postdilution HDF. The expression of Bax and nuclear factor κB was decreased in the serum after dialysis with the MCO dialyzer than with HDF. Compared with high-volume postdilution HDF, MCO dialysis did not provide greater removal of molecules below 12,000 Da, whereas it was superior in the removal of larger uremic middle molecule toxins in patients with kidney failure. Moreover, these results may be expected to have an anti-apoptotic effect on the human endothelium.