Humoral Response after Three Doses of mRNA-1273 or BNT162b2 SARS-CoV-2 Vaccines in Hemodialysis Patients.

The COVID-19 pandemic continues to be a worldwide health issue. Among hemodialysis (HD) patients, two-dose immunization schemes with mRNA vaccines have contributed to preventing severe COVID-19 cases; however, some have not produced a sufficient humoral response, and most have developed a rapid decline in antibody levels over the months following vaccination. This observational, prospective, multi-center study evaluated the humoral response in terms of presence and levels of IgG antibodies to the receptor-binding domain of the S1 spike antigen of SARS-CoV-2 (anti-S1-RBD IgG) to the third dose of SARS-CoV-2 mRNA vaccines, either the mRNA-1273 (Moderna) or BNT162b2 (Pfizer), in 153 patients from three dialysis units affiliated to Hospital Clínic of Barcelona (Spain). Most hemodialysis patients responded intensely to this third vaccine dose, achieving the seroconversion in three out of four non- or weak responders to two doses. Moreover, 96.1% maintained the upper limit or generated higher titers than after the second. BNT162b2 vaccine, active cancer, and immunosuppressive treatment were related to a worse humoral response. Every hemodialysis patient should be administered a third vaccine dose six months after receiving the second one. Despite the lack of data, immunosuppressed patients and those with active cancer may benefit from more frequent vaccine boosters.

Efficacy and safety of the Clearum dialyzer.

The Clearum dialyzer, built by Medtronic, became commercially available in several European countries in 2020, but there are still no reports of in vivo data. The aim of this study was to evaluate the efficacy and risk of hypoalbuminemia of this dialyzer compared with previously evaluated hemodialysis (HD), expanded hemodialysis (HDx), and postdilution hemodiafiltration (HDF) treatments. A prospective study was carried out in 15 patients. Each patient underwent seven dialysis sessions: FX80 Cordiax in HD, Clearum HS17 in HD, Phylther 17-SD in HDx, Theranova 400 in HDx, Phylther 17-G in postdilution HDF, Clearum HS17 in postdilution HDF, and FX80 Cordiax in postdilution HDF. The reduction ratios of urea, creatinine, ß2 -microglobulin, myoglobin, prolactin, α1 -microglobulin, α1 -acid glycoprotein, and albumin were compared intraindividually. Dialysate albumin loss was also measured. Comparison of dialysis techniques revealed no differences between small molecules, but HDx and HDF were significantly higher than HD with medium and large molecular weights. The Clearum dialyzer in HDF obtained similar results to FX80 Cordiax in HDF, was slightly superior to Phylther 17-G in HDF, and was statistically superior to both dialyzers in HDx. Albumin losses with the Clearum dialyzer were among the lowest, both in HD and HDF treatments. The highest global removal score (GRS) values were obtained with the helixone and Clearum dialyzers in HDF, with similar results both in HD and HDF. In addition, the GRS values with HDx treatments were statistically significantly higher than those with HD. The new Clearum dialyzer has excellent behavior and tolerance in HD and HDF. Its adequate permeability has been proven with its maximal performance in HDF, which could represent an upgrade versus its predecessor polyphenylene dialyzers.

SARS-CoV-2 Infection in a Spanish Cohort of CKD-5D Patients: Prevalence, Clinical Presentation, Outcomes, and De-Isolation Results.

INTRODUCTION: COVID-19 is a highly contagious disease that has easily spread worldwide. Outpatient maintenance hemodialysis seems to entail an increased risk of contagion, and previous reports inform of increased mortality among this population. METHODS: We retrospectively analyzed clinical and laboratory parameters, outcomes, and management once discharged of CKD-5D patients infected with SARS-CoV-2 from our health area. RESULTS: Out of the 429 CKD-5D population, 36 were diagnosed with SARS-CoV-2 infection (8%): 34 on in-center hemodialysis and 2 on peritoneal dialysis. Five were asymptomatic. The most common symptom was fever (70%), followed by dyspnea and cough. History of cardiovascular disease and elevation of LDH and C-reactive protein during admission were associated with higher mortality. Thirteen patients died (36%), 8 patients were admitted to an ICU, and survival was low (38%) among the latter. The mean time to death was 12 days. Most discharged patients got negative rRT-PCR in nasopharyngeal swabs within 26 days of diagnosis. However, there is a portion of cured patients that continue to have positive results even more than 2 months after the initial presentation. CONCLUSIONS: Patients on dialysis have an increased mortality risk if infected with SARS-CoV-2. Preventive measures have proven useful. Thus, proper ones, such as universal screening of the population and isolation when required, need to be generalized. Better de-isolation criteria are necessary to ensure an appropriate use of public health resources.

Impact of locking solutions on conditioning biofilm formation in tunnelled haemodialysis catheters and inflammatory response activation.

INTRODUCTION: The surface of tunnelled cuffed catheters provides an optimal environment for the development of biofilms, which have recently been described as conditioning films because of the presence of adherent biological materials. These biofilms are associated with infection and thrombosis and potentially increase patients' inflammatory response. These complications could be reduced by the use of locking solutions. OBJECTIVE: To analyse biofilm formation, using confocal and electron microscopy, in tunnelled cuffed catheters locked with three different solutions and to determine the relationship between these solutions and inflammatory response. STUDY DESIGN: This prospective study included 35 haemodialysis patients with tunnelled cuffed catheter removal for non-infection-related reasons. The participants were divided into three groups according to the lock solution used: (1) heparin 1: 5000 IU; (2) citrate 4%; and (3) taurolidine 1.35%, citrate 4% and heparin 500 IU (taurolock); in the latter group, 25,000 IU taurolidine-urokinase was used in the last weekly session. All tunnelled cuffed catheters were cultured, and the inner surface was evaluated with confocal and electron microscopy. The inflammatory profile of included patients was determined at tunnelled cuffed catheter removal. RESULTS: There were no differences in clinical or demographic variables between the three subgroups. Biofilm thickness was lower in the taurolidine group than in the citrate 4% and heparin groups (28.85 ± 6.86 vs 49.99 ± 16.56 vs 56.2 ± 15.67 µm, respectively; p < 0.001), as was biofilm volume (1.01 ±1.18 vs 3.7 ± 2.15 vs 5.55 ±2.44, µm3, respectively; p < 0.001). The mean interleukin-6 value was 39%, which was 50% lower than in the citrate and heparin groups, but without significance differences. CONCLUSION: Our results show that biofilms were found in all tunnelled cuffed catheters, but the thickness and volume were significantly lower in tunnelled cuffed catheters locked with taurolidine solution. Therefore, the type of locking solution used in tunnelled cuffed catheters should maintain tunnelled cuffed catheter sterility and prevent catheter-related bloodstream infections. No significant difference was observed in the inflammatory profile according to the type of locking solution.

Determining factors for hemodiafiltration to equal or exceed the performance of expanded hemodialysis.

The aim of the study was to compare expanded hemodialysis (HDx) with hemodiafiltration (HDF) at different infusion flows to identify the main determinants, namely blood flow (Qb), replacement volume, infusion flow (Qi), ultrafiltration flow (Quf ), filtration fraction (FF), and the point at which the effectiveness of HDF equals or exceeds that of HDx. We conducted a prospective, single-center study in 12 patients. Each patient underwent 12 dialysis sessions: six sessions with Qb 350 and six with Qb 400 mL/min; with each Qb, one session was with HDx and five sessions were with FX80 (one in HD, and four with Qi 50, 75, 90/100 mL/min or autosubstitution in postdilution HDF). The reduction ratios (RR) of urea, creatinine, ß2 -microglobulin, myoglobin, prolactin, α1 -microglobulin, α1 -acid glycoprotein, and albumin were compared intraindividually and the global removal score (GRS) was calculated. The mean replacement volume with Qb 350 mL/min was 13.77 ± 0.92 L with Qi 50 mL/min, 20.75 ± 1.17 L with Qi 75, 23.83 ± 1.92 L with Qi 90, and 27.51 ± 2.77 L with autosubstitution. Similar results were obtained with Qb 400 mL/min, and the results were only slightly higher with Qi 100 mL/min or in autosubstitution. The GRS was positively correlated with replacement volume with Qb 350 (R2  = 0.583) and with Qb 400 (R2  = 0.584); with Quf with Qb 350 (R2  = 0.556) and with Qb 400 (R2  = 0.604); and also with FF with Qb 350 (R2  = 0.556) and with Qb 400 mL/min (R2  = 0.603). The minimum convective volume in HDF from which it is possible to overcome the efficacy of HDx was 19.2 L with Qb 350 and 17.6 L with Qb 400 mL/min. The cut-off point of Quf at which HDF exceeded the effectiveness of HDx was 80.6 mL/min with Qb 350 and 74.1 mL/min with Qb 400 mL/min. The cut-off point at which FF in HDF exceeded the effectiveness of the HDx was 23.0% with Qb 350 and 18.6% with Qb 400 mL/min. In conclusion, this study confirms the superiority of postdilution HDF over HDx when replacement volume, convective volume, Quf , or FF exceeds certain values. Increasing the Qb in postdilution HDF manages to increase the convective dose and more easily overcome the HDx.

Study of Biocompatibility of Membranes in Online Hemodiafiltration.

BACKGROUND: The biocompatibility of dialysis membranes is a determining factor in avoiding chronic microinflammation in patients under haemodialysis. Lower biocompatibility has been related to increased inflammatory status, which is known to be associated with cardiovascular events. Classically, cellulose membranes have been considered bioincompatible. A new-generation of asymmetric cellulose triacetate (CTA) membranes allows the performance of high convective transport techniques, but there have been no studies of their biocompatibility. The aim of the present study was to analyze and compare the biocompatibility characteristics of 4 membranes, including CTA, in online hemodiafiltration (OL-HDF) patients. METHODS: We included 15 patients in -OL-HDF. After a 2-week washout period with helixone membrane, each patient was treated with the 4 membranes (polyamide, polynephron, helixone and CTA) for 4 weeks in a randomized order. The other dialysis parameters were kept stable throughout the study. We studied changes in markers of the activation of the complement system, monocytes, platelets, and adhesion molecules with the 4 membranes, as well as inflammatory parameters. RESULTS: Biocompatibility was similar among the membranes. There were no sustained differences in complement activation, measured by C3a and C5a levels, or in platelet activation, determined by levels of P-selectin and platelet-derived microparticles (CD41a+). No differences were observed in activated monocyte levels (CD14+/CD16+) or in plasma levels of interleukin (IL)-1, IL-6, IL-10 or high-sensitivity C-reactive protein, although tumour necrosis factor-α levels decreased when the patients were dialyzed with CTA. No significant differences were found in markers of endothelial damage, assessed by levels of plasminogen activator inhibitor-1 and adhesion molecules (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1). CONCLUSION: The 4 membranes evaluated in this study in stable patients on OL-HDF, including the new-generation CTA, show similar biocompatibility with the methods applied.

High-permeability alternatives to current dialyzers performing both high-flux hemodialysis and postdilution online hemodiafiltration.

Most high-flux dialyzers can be used in both hemodialysis (HD) and online hemodiafiltration (OL-HDF). However, some of these dialyzers have higher permeability and should not be prescribed for OL-HDF to avoid high albumin losses. The aim of this study was to compare the safety and efficacy of a currently used dialyzer in HD and OL-HDF with those of several other high permeability dialyzers which should only be used in HD. A prospective, single-center study was carried out in 21 patients. Each patient underwent 5 dialysis sessions with routine dialysis parameters: 2 sessions with Helixone (HD and postdilution OL-HDF) and 1 session each with steam sterilized polyphenylene, polymethylmethacrylate (PMMA), and medium cut-off (MCO) dialyzers in HD treatment. The removal ratios (RR) of urea, creatinine, ß2 -microglobulin, myoglobin, prolactin, α1 -microglobulin, α1 -acid glycoprotein, and albumin were compared intraindividually. A proportional part of the dialysate was collected to quantify the loss of various solutes, including albumin. Urea and creatinine RRs with the Helixone-HDF and MCO dialyzers were higher than with the other 3 dialyzers in HD. The ß2 -microglobulin, myoglobin and prolactin RRs with Helixone-HDF treatment were significantly higher than those obtained with all 4 dialyzers in HD treatment. The ß2 -microglobulin value obtained with the MCO dialyzer was also higher than that obtained with the other 3 dialyzers in HD treatment. The myoglobin RR with MCO was higher than those obtained with Helixone and PMMA in HD treatment. The prolactin RR with Helixone-HD was significantly lower than those obtained in the other 4 study sessions. The α1 -microglobulin and α1 - acid glycoprotein RRs with Helixone-HDF were significantly higher than those obtained with Helixone and PMMA in HD treatment. The albumin loss varied from 0.54 g with Helixone-HD to 3.3 g with polyphenylene. The global removal score values ((UreaRR + ß2 -microglobulinRR + myoglobinRR + prolactinRR + α1 -microglobulinRR + α1 -acid glycoproteinRR - albuminRR )/6) were 43.7% with Helixone-HD, 47.7% with PMMA, 54% with polyphenylene, 54.8% with MCO and 59.6% with Helixone-HDF, with significant differences. In conclusion, this study confirms the superiority of OL-HDF over HD with the high-flux dialyzers that allow both treatments. Although new dialyzers with high permeability can only be used in HD, they are in an intermediate position and some are very close to OL-HDF.

Improved Control of Secondary Hyperparathyroidism in Hemodialysis Patients Switching from Oral Cinacalcet to Intravenous Etelcalcetide, Especially in Nonadherent Patients.

BACKGROUND: Etelcalcetide is a novel second-generation calcimimetic that, because of its intravenous administration, could improve treatment adherence in secondary hyperparathyroidism (SHPT). The aim of this study was to evaluate the effectiveness of etelcalcetide compared with that of cinacalcet in controlling SHPT in patients under hemodialysis. METHODS: A prospective observational study was performed in 29 patients with SHPT under hemodialysis who switched from cinacalcet to etelcalcetide with a follow-up of 6 months. A survey was conducted of adherence to the oral calcimimetic. The primary end-point of the study was to assess whether etelcalcetide was more effective than cinacalcet in controlling SHPT. RESULTS: After the switch of treatment, none of the patients developed clinical intolerance or new adverse effects. Etelcalcetide was more effective than cinacalcet in controlling intact parathyroid hormone (iPTH), with an overall decrease in iPTH levels that was significant from the second month. Average calcium levels remained within the normal range, with a higher percentage of hypocalcemia with etelcalcetide (6.9 vs. 13.8%), which was asymptomatic in all cases. Patients who were nonadherent to cinacalcet (38%) showed a significant reduction in calcium and iPTH during follow-up with etelcalcetide. The adherent group (62%) also showed a trend to lower iPTH levels reaching statistical significance after 5 months of follow-up. The dose conversion factor for the switch from cinacalcet to etelcalcetide was etelcalcetide/session = 0.111*mg cinacalcet/day + 0.96, R2 = 0.57. CONCLUSIONS: Etelcalcetide was more effective than cinacalcet in this patient population, especially in the nonadherent subgroup, leading to better SHPT control without adverse effects.

A phase 1b randomized, placebo-controlled clinical trial with SNF472 in haemodialysis patients.

AIMS: SNF472 is a calcification inhibitor that is being studied as a novel treatment for calciphylaxis and cardiovascular calcification (CVC). A first study showed acceptable safety and tolerability in a single ascending dose administration in healthy volunteers and a single dose administration in haemodialysis (HD) patients. This study aimed to assess the safety, tolerability, and pharmacokinetics/pharmacodynamics relationship of intravenous SNF472 in HD patients in a multiple ascending dose administration trial with 5 doses tested for 1 week (3 administrations) and 1 dose tested for 4 weeks (12 administrations). METHODS: This double blind, randomized, placebo-controlled Phase 1b study investigated the safety, tolerability, pharmacokinetics and pharmacodynamics of SNF472 after repeated administrations to HD patients for up to 28 days. A pharmacodynamic assessment was performed to evaluate the potential for SNF472 to inhibit hydroxyapatite (HAP) formation. Patients were grouped into 2 cohorts, receiving multiple ascending doses for 1 week (1 to 20 mg/kg, Cohort 1) and 1 dose of 10 mg/kg for 4 weeks (Cohort 2) of intravenous SNF472. RESULTS: Physical status, body weight, cardiorespiratory function, body temperature and laboratory parameters were in the normal range. No clinically relevant effects on heart rate or blood pressure were observed. No abnormal electrocardiogram or QTcB period were reported. The peak plasma concentration (7.6, 16.1, 46.0 and 66.9 µg/mL for 3, 5, 12.5 and 20 mg/kg, respectively) was observed at the end of the 4-hour infusion and thereafter concentrations declined rapidly with half-life between 32 and 65 min. SNF472 at 10 mg/kg inhibited dose dependently HAP crystallization in plasma samples after 28 days of treatment (78% inhibition, P < .001). CONCLUSIONS: SNF472 is safe and well tolerated in HD patients after 2 schemes: multiple ascending doses for 1 week and after repeated dosing of 10 mg/kg for 4 weeks. In both schemes, SNF472 inhibits the induction of HAP crystallization. These results provide support for the use of SNF472 as a novel treatment for CVC in end-stage renal disease.

Vancomycin hemodialysis: Clearance differences between high-flux hemodialysis and on-line hemodiafiltration.

The aim of this study was to analyze the differences between vancomycin clearance (Kd) with high-flux hemodialysis (HFHD) and on-line hemodiafiltration (OL-HDF). The OL-HDF therapy combined the diffusion and convective transport of solutes. To compare the Kd, a vancomycin loading dose of 1 g was administered intravenously post-dialysis to 11 chronic and anuric (<100 mL/24 h) hemodialysis patients, undergoing HFHD and post-dilutional OL-HDF in consecutive therapies. Additional doses of 0.5 g were administered after 45 minutes at the end of each dialysis therapy during antibiotic treatment. Blood samples were drawn from arterial and venous lines at the start of hemodialysis sessions and at the first, second, third, and fourth hours. Additional samples were drawn at 15, 30, and 45 minutes after the end of dialysis therapy. Vancomycin plasma concentration, blood urea nitrogen (BUN), creatinine, and ß2 -microglobulin were measured. The patients' hydration status was evaluated by bioimpedance analysis. The mean of vancomycin dialyzer clearance (Kddc ) calculated was 110.8 ± 15 mL/min with HFHD and 146.8 ± 13.8 mL/min with OL-HDF (P = 0.025). Significant differences were also obtained for ß2 -microglobulin clearance, Kddc 72.6 ± 15.4 mL/min with HFHD and 113.4 ± 24.2 mL/min with OL-HDF (P = 0.012), whereas no differences were found for BUN or creatinine. Additionally, to analyze differences between HFHD and OL-HDF, a variable volume dual pool mathematical model was developed to estimate the body clearance (Kdbc ), extraction mass (Me ), and inter-compartment mass-transfer coefficient (K12 ) of each molecule. A higher vancomycin Kddc with OL-HDF produced by convection improved removal of antibiotic; this can compromise achieving a therapeutic concentration target. We recommended evaluating increased loading doses of vancomycin and avoiding administration during OL-HDF to assure adequate treatment.

Mortality reduction by post-dilution online-haemodiafiltration: a cause-specific analysis.

Background: From an individual participant data (IPD) meta-analysis from four randomized controlled trials comparing haemodialysis (HD) with post-dilution online-haemodiafiltration (ol-HDF), previously it appeared that HDF decreases all-cause mortality by 14% (95% confidence interval 25; 1) and fatal cardiovascular disease (CVD) by 23% (39; 3). Significant differences were not found for fatal infections and sudden death. So far, it is unclear, however, whether the reduced mortality risk of HDF is only due to a decrease in CVD events and if so, which CVD in particular is prevented, if compared with HD. Methods: The IPD base was used for the present study. Hazard ratios and 95% confidence intervals for cause-specific mortality overall and in thirds of the convection volume were calculated using the Cox proportional hazard regression models. Annualized mortality and numbers needed to treat (NNT) were calculated as well. Results: Besides 554 patients dying from CVD, fatal infections and sudden death, 215 participants died from 'other causes', such as withdrawal from treatment and malignancies. In this group, the mortality risk was comparable between HD and ol-HDF patients, both overall and in thirds of the convection volume. Subdivision of CVD mortality in fatal cardiac, non-cardiac and unclassified CVD showed that ol-HDF was only associated with a lower risk of cardiac casualties [0.64 (0.61; 0.90)]. Annual mortality rates also suggest that the reduction in CVD death is mainly due to a decrease in cardiac fatalities, including both ischaemic heart disease and congestion. Overall, 32 and 75 patients, respectively, need to be treated by high-volume HDF (HV-HDF) to prevent one all-cause and one CVD death, respectively, per year. Conclusion: The beneficial effect of ol-HDF on all-cause and CVD mortality appears to be mainly due to a reduction in fatal cardiac events, including ischaemic heart disease as well as congestion. In HV-HDF, the NNT to prevent one CVD death is 75 per year.

Effect of a postoperative exercise program on arteriovenous fistula maturation: A randomized controlled trial.

Exercises after arteriovenous fistula (AVF) creation may help to improve maturation; however, their usefulness has only been examined in indirect, non-comparative studies or small trials. Between June 2013 and November 2014, we included all ambulatory patients with stages 5-5D chronic kidney disease who were candidates for the creation of a native AVF in our center. After surgery, all patients were randomized to an exercise group or a control group with single-blind control. At 1 month postoperatively, clinical maturation (expert nurse inspection) and ultrasonographic maturation (flow >500 mL/min, venous diameter >5 mm and depth <6 mm) were assessed in all patients. A total of 72 patients were randomized, 3 were lost to follow-up, and 69 were finally analyzed. The mean age was 66.8 years (standard deviation 13.8), 70.0% were men, and 65.2% were in pre-dialysis. After surgery (42.0% had distal AVF), the patients were randomized (31 controls, 38 exercise group). At 1 month after surgery, global clinical and ultrasonographic maturation was assessed in 88.4% and 78.3% of AVF, respectively (kappa = 0.539). Non-significant differences in clinical or ultrasonographic maturation were seen between exercise and control group (94.7% vs. 80.6%, P = 0.069; 81.6% vs. 74.2%, P = 0.459). A stepwise logistic regression was performed to control previously analyzed asymmetrically distributed confounding factors (AVF localization), revealing that the exercise group showed greater clinical, but not ultrasonographic, maturation (odds ratio [OR] 5.861, 95% confidence interval: 1.006-34.146 and OR 2.403, 0.66-8.754). A postoperative controlled exercise program after AVF creation seems to increase 1-month clinical AVF maturation in distal accesses. Furthermore, exercise programs should be taken into account, especially in distal accesses.

Tunneled catheters with taurolidine-citrate-heparin lock solution significantly improve the inflammatory profile of hemodialysis patients.

Mortality and morbidity are significantly higher among patients with dialysis catheters, which has been associated with chronic activation of the immune system. We hypothesized that bacteria colonizing the catheter lumen trigger an inflammatory response. We aimed to evaluate the inflammatory profile of hemodialysis patients before and after locking catheters with an antimicrobial lock solution. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were measured in serum, and levels of mRNA gene expression of IL-6, IL-10, and TNF-α were analyzed in peripheral blood mononuclear cells (PBMC). Samples were obtained at baseline and again after 3 months' use of taurolidine-citrate-heparin lock solution (TCHLS) in 31 hemodialysis patients. The rate of catheter-related bloodstream infections (CRBSI) was 1.08 per 1,000 catheter-days in the heparin period and 0.04 in the TCHLS period (P = 0.023). Compared with the baseline data, serum levels of hs-CRP and IL-6 showed median percent reductions of 18.1% and 25.2%, respectively (P < 0.01), without significant changes in TNF-α or IL-10 levels. Regarding cytokine gene expression in PBMC, the median mRNA expression levels of TNF-α and IL-6 decreased by 20% (P < 0.05) and 19.7% (P = 0.01), respectively, without changes in IL-10 expression levels. The use of TCHLS to maintain the catheter lumen sterility significantly reduces the incidence of CRBSI and improves the inflammatory profile in hemodialysis patients with tunneled catheters. Further studies are needed to evaluate the potential beneficial effects on clinical outcomes.

Time savings associated with C.E.R.A. once monthly: a time-and-motion study in hemodialysis centers in five European countries.

OBJECTIVE: This time-and-motion study aimed to quantify healthcare personnel time associated with routine anemia-management tasks for maintenance therapy with C.E.R.A. (continuous erythropoietin receptor activator) that treats anemia with once-monthly injections versus other erythropoiesis-stimulating agents ('Other ESAs'), including shorter-acting ESAs (epoetin alfa, epeotin beta) and darbepoetin alfa. METHODS AND DESIGN: This was a non-interventional, observational study where patients were treated for anemia according to individual center practices. Time taken to complete frequent anemia-management tasks for both groups (C.E.R.A. vs. 'Other ESAs') was recorded and potential annual time savings per patient and per center following assumed 100% uptake of C.E.R.A. once monthly were estimated. RESULTS: For 'Other ESAs', the average total time spent per patient per year on frequent anemia management-related tasks ranged from 48 minutes in Spain to 265 minutes in Poland. For C.E.R.A. once monthly, the average total time spent per patient per year ranged from 12 minutes in Spain to 39 minutes in Poland, a reduction in actual time spent of 76-89% versus 'Other ESAs'. 100% adoption of C.E.R.A. once monthly may result in average annual time savings of 26-553 hours, a reduction of 67-95% depending on center size and frequency distribution of 'Other ESAs'. LIMITATIONS: Due to variability in treatment practices between centers (differences in task, description and frequency distribution of 'Other ESAs') and the small numbers of centers participating in each country, it is difficult to generalize annual per patient time results to reflect each country. Per center results should be interpreted with caution as they were derived based on specific center sizes that may not reflect typical center sizes in the country. CONCLUSIONS: Adoption of C.E.R.A. once monthly could offer substantial time savings on frequent anemia management-related tasks versus 'Other ESAs'; allowing re-allocation of scarce resources to other aspects of patient care.

Mid-dilution hemodiafiltration: a comparison with pre- and postdilution modes using the same polyphenylene membrane.

As a change from Diapes to polyphenylene membrane in the mid-dilution filter has recently been developed, the aim of this study was to compare mid-dilution using this new dialyzer versus pre- and postdilution. The prospective study included 20 patients who underwent 4 hemodiafiltration (HDF) sessions: 1.7 m(2) polyphenylene and predilution infusion flow (Qi) 200 ml/min, 1.7 m(2) and postdilution Qi 100 ml/min, 1.9 and 2.2 m(2) mid-dilution both with Qi 200 ml/ min. The urea and creatinine reduction ratios were slightly higher in postdilution. The beta(2)-microglobulin (85.8%), myoglobin (73.6%), prolactin (67.8%) and retinol-binding protein (29.2%) reduction ratios with 1.9 m(2) mid-dilution, which was similar to 2.2 m(2) mid-dilution, were significantly higher than with the post- and predilution modes. Mid-dilution appears to be a good HDF alternative that allows a better removal of larger molecules than postdilution and, mainly, predilution. Mid-dilution using 1.9 or 2.2 m(2) dialyzers, at the same convective volume, showed a similar removal.

Optimizing the prescription of hemodiafiltration.

Hemodiafiltration with larger amounts of substitution fluid offers an optimal way to remove uremic substances. Hemodiafiltration could be indicated for all hemodialysis patients. Large observational studies have shown an association of a lower mortality risk with hemodiafiltration using more than 15 liters of substitution fluid. Specific indications should be considered because hemodiafiltration has been reported to be effective against hyperphospatemia, malnutrition, insomnia, irritability, restless-leg syndrome, polyneuropathy, anemia, itching and joint pain, and may prevent dialysis-associated amyloidosis. In this chapter, hemodiafiltration prescriptions concerning blood and dialysate fl ow, infusion rate, vascular access and frequency are detailed.