Comparison of citrate dialysate in pre- and post-dilution online hemodiafiltration: effect on clot formation and adequacy of dialysis in hemodialysis patients

BACKGROUND

Citrate dialysate (CD) has been successfully used in conventional hemodialysis and continuous renal replacement therapy; however, no study has compared pre- and post-dilution online hemodiafiltration (oL-HDF). Therefore, we aimed to investigate the efficacy of citrate anticoagulation for oL-HDF and the metabolic changes and quality of life of patients on hemodialysis treated using both modes.

METHOD

Eight dialysis patients were treated with CD containing 0.8 mmol of citric acid for 4 weeks in each phase. Visual clotting scores were investigated as the primary endpoints. Adequacy of dialysis, laboratory parameters, and quality of life were measured as secondary objectives.

RESULTS

The mean clotting scores in the pre-dilution mode were significantly lower than those in the post-dilution mode and in all phases except the heparin-free phase (p < 0.001 in the baseline phase, p = 0.001 in phase 1, and p = 0.023 in phase 2). The values of Kt/V in both modalities were comparable except during the baseline phase, in which the values of pre-dilution were significantly greater than post-dilution (2.36 ± 0.52/week vs. 1.87 ± 0.33/week;95% CI -0.81 to -0.19, p = 0.002). The patient's quality of life regarding their physical activity level was significantly higher in the post-dilution mode than in the pre-dilution mode at baseline and in phase 1 (p = 0.014 and 0.004 at baseline and in phase 1, respectively). Metabolic changes did not differ between the two modes.

CONCLUSION

Citrate dialysate decreased or prevented anticoagulation in both pre- and post-dilution modes of oL-HDF without significant side effects and had comparable adequacy of dialysis.

High volume online hemodiafiltration: a global perspective and the Brazilian experience

Online hemodiafiltration (HDF) is a rapidly growing dialysis modality worldwide. In Brazil, the number of patients with private health insurance undergoing HDF has exceeded the number of patients on peritoneal dialysis. The achievement of a high convection volume was associated with better clinical imprand patient - reported outcomes confirming the benefits of HDF. The HDFit trial provided relevant practical information on the implementation of online HDF in dialysis centers in Brazil. This article aims to disseminate technical information to improve the quality and safety of this new dialysis modality.

Experience with Tandem Pre-Dilution Online Hemodiafiltration and Centrifugal Plasma Exchange in Pretransplant Desensitization for Abo-Incompatible Kidney Transplantation: A Case Report

BACKGROUND

In the use of therapeutic plasma exchange (TPE) as antibody removal therapy for ABO-incompatible (ABOi) kidney transplantation, it is technically possible to perform online hemodiafiltration (OHDF) and TPE simultaneously for patients who are receiving OHDF. In this study, we report tandem therapy of pre-dilution OHDF and centrifugal plasma exchange (cTPE), instead of membrane plasma exchange, which is the mainstay of TPE in Japan.

METHODS

A total of 14 sessions of tandem cTPE and pre-dilution OHDF were performed as preoperative antibody removal therapy for 6 ABOi kidney transplant recipients. cTPE intra-circuit pressure, decreased antibody titer, and adverse events were evaluated. The study was carried out following the ethical standards of the Declaration of Helsinki and Istanbul. Donors were not prisoners or individuals who were coerced or paid.

RESULTS

The tandem therapy was completed safely in 12 of the 14 sessions, with no problems such as pressure upper and lower limit alarms or circuit coagulation. In 2 sessions, the tandem therapy had to be interrupted due to coagulation on the dialysis circuit side. Antibody titers were reduced by a median of 3-fold for both IgG and IgM. There was no acute antibody-associated rejection.

CONCLUSIONS

In preoperative apheresis therapy for ABOi kidney transplantation, tandem therapy of pre-dilution OHDF and cTPE may be a useful treatment option that can be performed safely and results in sufficient reduction of antibody levels.

A pilot study of intensive short-time continuous renal replacement therapy to substitute maintenance hemodialysis during transitional period of COVID-19

INTRODUCTION

There is a lack of perfect solutions for maintenance hemodialysis (MHD) in patients with a high transmission risk of SARS-CoV-2.

METHODS

MHD patients with a high risk of SARS-CoV-2 transmission from April 1 to June 30, 2022, were recruited. We performed 4-h continuous renal replacement therapy with Prismaflex dialysis machine and ST100 suite using continuous venovenous hemodiafiltration (CVVHDF) mode with a fluid exchange volume of 8000 mL/h.

RESULTS

Forty-five MHD patients were included with a median dialysis age of 91 months. Overall spKt/V reached 0.96 ± 0.19. Urea reduction ratio was 50.29 ± 7.60% with the ultrafiltration of 2.18 ± 0.79 kg. Dry weight was significantly inversely correlated with spKt/V (R = -0.563, p < 0.001). Female gender was a significant positive factor of spKt/V. Preheating of replacement solution using an incubator solved the complication of shivering in most patients.

CONCLUSION

Intensive short-time CVVHDF may be considered as an alternative for routine MHD during COVID-19 transitional period.

The short-term effect of hemodialysis on the level of high-sensitive cardiac troponin T - A systematic review

INTRODUCTION

Patients with end-stage renal disease (ESRD) have an increased risk of cardiovascular disease, but interpreting cardiac troponin is difficult in this population. The effect of renal replacement therapy (RRT) is important to consider when interpreting serial cardiac troponin T (cTnT) results for patients with ESRD suspected of acute coronary syndrome (ACS). The aim of this systematic review is to answer how low-flux hemodialysis (LF-HD), high-flux hemodialysis (HF-HD), and hemodiafiltration (HDF) affect the blood concentration of high-sensitive cardiac troponin T (hs-cTnT).

METHOD

Several databases were searched and identified records were evaluated independently by two of the authors. Pre- and postdialysis hs-cTnT concentrations together with other relevant data were extracted from the included studies. The quality (potential bias and applicability issues) were assessed for each of the included studies.

RESULTS

The literature search identified 2,540 records and 15 studies were included. The relative pre- to postdialysis change of hs-cTnT varied from -41 to 29%. LF-HD increased the hs-cTnT concentration with relative changes between 2 and 17%. HDF decreased the concentration with relative changes from -41% to -9%. Both increases and decreases were seen for HF-HD (-16% to 12%).

DISCUSSION/CONCLUSION

In this systematic review, we found LF-HD to increase the hs-cTnT concentration and HDF to decrease the concentration. Results for HF-HD and unspecified HD are more heterogeneous. Because of the differences between the included studies, a meta-analysis was not meaningful. This systematic review can help with the assessment of patients with ESRD suspected of ACS in relation to hemodialysis/HDF treatment.

Removal performance of pre- and post-dilution online hemodiafiltration using identical hemodiafilters in the same patients

Online hemodiafiltration (OHDF) for renal replacement therapy has two modes: pre- (pre-OHDF) and post-dilution OHDF (post-OHDF). To elucidate the precise differences between the two modes, a clinical study was performed using the same polysulfone hemodiafilters in the same patients. Eight patients were treated with ABH™-22PA for 6 weeks: 3 weeks of pre-OHDF (with substitution volumes of 24, 36, and 48 L) and 3 weeks of post-OHDF (6, 8, and 10 L). The reduction ratios of urea, uric acid (UA), creatinine (CRE), inorganic phosphorus (iP), beta-2-microglobulin (β2-MG), and alpha-1-microglobulin (α1-MG) were evaluated. The removal amounts of β2-MG, α1-MG, and albumin were also evaluated by analyzing the spent dialysis fluids. The types and numbers of adverse events (AEs) and device malfunctions were recorded. The reduction ratios of urea, UA, CRE, iP, and β2-MG were comparable among all conditions, while that of α1-MG tended to be slightly higher in post-OHDF than in pre-OHDF. The removal amounts of α1-MG and albumin in pre-OHDF and post-OHDF were significantly greater with the maximum substitution volume than with the minimum volume. However, the selective removal indices, which were obtained by dividing the amount of α1-MG removed by the albumin level, tended to be slightly higher in pre- than in post-OHDF. No device-related AEs or device malfunctions occurred in either mode. No significant differences in inflammatory responses, evaluated by high-sensitivity C-reactive protein and interleukin-6, were observed. This study provides removal performance and safety data regarding the application of ABH-22PA for pre- and post-OHDF.

Effects of nutritional supplementation stabilizing muscle mass loss in older patients on hemodiafiltration

BACKGROUND & AIMS

Malnutrition is common in older individuals with end-stage renal disease on maintenance dialysis. Whether nutritional supplementation may improve skeletal muscle mass (SMM) and survival rate in this population is uncertain. We aimed to analyze the effect of a year of nutritional supplementation on muscle mass and survival rate in older patients on hemodiafiltration.

METHODS

In this observational study, older patients (≥65 years old) on maintenance hemodiafiltration were selected to receive nutritional counselling + nutritional supplementation (N = 85, Supp+) or nutritional counselling alone (N = 47, Supp-) and followed for 1 year. The outcomes were a change in SMM and sarcopenia diagnosis. The secondary outcome was 1-year mortality rate. Nutritional parameters included calf circumference, body mass index, anthropometric measurements, subjective global assessment, and handgrip strength (HGS). Data were evaluated using GLM for repeated measures with adjustment for covariates (age and diabetes).

RESULTS

Malnutrition was found in 50.8% of patients. At baseline, patients from the Supp+ group were older and had worse nutritional parameters including hand grip strength, calf circumference, anthropometric findings and sarcopenia (all p values < 0.05). During the follow-up, there was no significant change in sarcopenia (from 50.8% to 58.3%, p = 0.108), and there was a more pronounced decrease in the SMM index in the Supp-group (p = 0.049), with a significant intervention interaction (p = 0.030). Twenty deaths occurred, 7 (35%) in the Supp- and 13 (65%) in the Supp+ group (p = 0.540). SMM index (relative risk 0.90, p = 0.030) and age (relative risk 1.07, p = 0.046) were independently associated with higher mortality rates.

CONCLUSION

Nutritional supplementation in older and malnourished individuals undergoing hemodiafiltration mitigates the loss of the SMM index and benefits survival rate.

Severe disseminated infection by hypermucoviscous Klebsiella pneumoniae successfully treated by intensive therapy with continuous hemodiafiltration using AN69ST: A case report and review of the literature

Klebsiella pneumoniae (Kpn) is one of the most common gram-negative bacilli causing lung, urinary tract, and biliary tract infections. However, as a distinct entity from classic Kpn, hypervirulent Kpn causing liver abscess, endophthalmitis, and lung abscess with poor prognoses has been reported mainly in East and Southeast Asia since the mid-1980s. Although the definition of hypervirulent Kpn is unclear, the hypermucoviscosity of Kpn is considered an important feature of hypervirulence. We present a case of emphysematous pyelonephritis accompanied by septic shock and acute kidney injury caused by hypermucoviscous Kpn infection that was successfully treated by intensive treatment. A 70-year-old woman with type 2 diabetes mellitus was diagnosed with emphysematous pyelonephritis, and string test-positive Kpn was detected in blood and urine cultures and percutaneous catheter drainage fluid from the renal pelvis. The patient was treated with intensive therapies including antibiotics, ventilator management, and continuous hemodiafiltration (CHDF) using AN69ST, which can absorb cytokines. During the course of treatment, the infection was complicated by pyogenic spondylitis, which was cured by antimicrobial therapy, and the patient was transferred to another hospital for rehabilitation on day 119 after admission. Hypermucoviscous Kpn infection often has a severe course, and it is important to initiate multidisciplinary treatment at an early stage, including rifampicin, which is expected to inhibit the viscosity of hypermucoviscous Kpn. In the current case, immediate CHDF using AN69ST was also considered a life-saving treatment because it improved both volume overload and neutrophil-activated hypercytokinemia.

Early clinical observation of supra-hemodiafiltration with endogenous reinfusion in the treatment of uremic pruritus

BACKGROUND

To evaluate the clinical efficacy of supra-hemodiafiltration with endogenous reinfusion (Supra-HFR) for pruritus in uremic maintenance hemodialysis (HD) patients and explore the possible mechanism.

METHODS

This study prospectively included 60 patients with uremia who underwent maintenance hemodialysis and developed pruritus. Patients were randomly divided into a study group (30 cases) and a control group (30 cases). Patients in the study group underwent dialysis once a week with Supra-HFR and twice a week with HD. The group received HD dialysis 3 times a week. Visual analog scales (VAS) scores, 5-D itch scale scores, and 12-Item Pruritus Severity Scale (12-PSS) were used to evaluate the itching degree of patients. Quality of life was assessed using KDTA and SF-36 scores. Blood levels of hypersensitive C-reactive protein, calcium ion (Ca2+), phosphorus ion (P3+ ), free parathyroid hormone (iPTH), and β2-microglobulin (β2-MG) were compared between the two groups before treatment and at follow-up 24 weeks after treatment.

RESULTS

Before treatment, there was no significant difference in VAS, 5-D itch scale, and 12-PSS score between the study group and the control group (all p > 0.05). After 24 weeks of treatment, the VAS score of the study group (2.82 ± 0.91) was significantly lower than that of the control group (7.47 ± 1.32, p < 0.001), the 5-D itch scale score of the study group (9.47 ± 2.34) was significantly lower than that of the control group (18.53 ± 4.02, p < 0.001), the 12-PSS score of the study group (11.20 ± 1.81) was significantly lower than that of the control group (16.47 ± 2.09, p < 0.001). KDTA of the study group (64.17 ± 8.07 vs. 47.83 ± 13.46, p < 0.001) and SF-36 scores (65.37 ± 6.28 vs. 55.90 ± 14.28, p = 0.002) were significantly higher than that in the control group. The levels of hs-CRP, P3+ , iPTH, and β2-MG in the study group after treatment were lower than those before treatment, and lower than those in the control group after treatment (all p < 0.05).

CONCLUSIONS

The Supra-HFR can effectively reduce the itching symptoms of uremia patients and improve their quality of life.

Dual dialyzer hemodiafiltration: A new extracorporeal dialysis treatment modality for patients with end-stage kidney disease

BACKGROUND

The introduction of high flux (HF) hemodialyzers and their application in single dialyzer hemodiafiltration (sdHDF) for patients on extracorporeal dialysis (ECD) therapy has improved the extraction of uremic toxins, including the low molecular weight protein (LMWP) beta 2 microglobulin (β2M, 11.6 kDa). Similar increases in the extraction of protein-bound uremic toxins (PBUT) and larger LMWP (15-50 kDa) remain elusive. High concomitant losses of albumin prohibit the use of medium cutoff (MCO) or protein-losing hemodialyzers for sdHDF to increase the extraction of these molecules by convective transfer.

METHODS

A new extracorporeal dialysis treatment modality, dual dialyzer hemodiafiltration (ddHDF), has been designed together with a mathematical model to compare its predicted performance to that of sdHDF in the extraction of solute. The extra process that distinguishes ddHDF from sdHDF is the secondary ultrafiltration and partial reinfusion of the effluent hemodiafiltrate from the primary hemodialyzer. This allows MCO and protein-losing hemodialyzers to be used to increase the extraction of both LMWP and PBUT without excessive concomitant loss of albumin.

RESULTS

Data from the mathematical model show that ddHDF could increase the extraction of smaller and larger LMWP by an extra 102% and 220%, respectively, compared to standard HF sdHDF, while restricting the loss of albumin to 0.83 g per hour of treatment. In using albumin as a recyclable carrier molecule for the extraction of PBUT from plasma ddHDF has the potential to increase PBUT reduction ratios (RR's) to 49% by convection alone. Even higher RR's are possible if the dialysate volume flow rate can be increased beyond 600 mL/min.

CONCLUSION

ddHDF provides an opportunity for a step change increase in the level of extraction of both larger LMWP and PBUT in patients with end-stage kidney disease.

Removal of Middle Molecules and Dialytic Albumin Loss: A Cross-over Study of Medium Cutoff and High-Flux Membranes with Hemodialysis and Hemodiafiltration

Key Points

HDF and MCO have shown greater clearance of middle-size uremic solutes in comparison with HF dialyzers; MCO has never been studied in HDF. MCO in HDF does not increase the clearance of B2M and results in a higher loss of albumin.

Background

Middle molecule removal and albumin loss have been studied in medium cutoff (MCO) membranes on hemodialysis (HD). It is unknown whether hemodiafiltration (HDF) with MCO membranes provides additional benefit. We aimed to compare the removal of small solutes and β 2-microglobulin (B2M), albumin, and total proteins between MCO and high-flux (HFX) membranes with both HD and HDF, respectively.

Methods

The cross-over study comprised 4 weeks, one each with postdilutional HDF using HFX (HFX-HDF), MCO (MCO-HDF), HD with HFX (HFX-HD), and MCO (MCO-HD). MCO and HFX differ with respect to several characteristics, including membrane composition, pore size distribution, and surface area (HFX, 2.5 m2; MCO, 1.7 m2). There were two study treatments per week, one after the long interdialytic interval and another midweek. Reduction ratios of vitamin B12, B2M, phosphate, uric acid, and urea corrected for hemoconcentration were computed. Dialysis albumin and total protein loss during the treatment were quantified from dialysate samples.

Results

Twelve anuric patients were studied (six female patients; 44±19 years; dialysis vintage 35.2±28 months). The blood flow was 369±23 ml/min, dialysate flow was 495±61 ml/min, and ultrafiltration volume was 2.8±0.74 L. No significant differences were found regarding the removal of B2M, vitamin B12, and water-soluble solutes between dialytic modalities and dialyzers. Albumin and total protein loss were significantly higher in MCO groups than HFX groups when compared with the same modality. HDF groups had significantly higher albumin and total protein loss than HD groups when compared with the same dialyzer. MCO-HDF showed the highest protein loss among all groups.

Conclusions

MCO-HD is not superior to HFX-HD and HFX-HDF for both middle molecule and water-soluble solute removal. Protein loss was more pronounced with MCO when compared with HFX on both HD and HDF modalities. MCO-HDF has no additional benefits regarding better removal of B2M but resulted in greater protein loss than MCO-HD.

Improved β2-Microglobulin and Phosphorous Removal with Expanded Hemodialysis and Online Hemodiafiltration versus High-Flux Hemodialysis: A Cross-Over Randomized Clinical Trial

INTRODUCTION

Expanded hemodialysis (HDx) is expected to provide enhanced permeability of medium-sized molecules, selective solute retention, and better internal retrofiltration. The primary objective of this study was to compare the efficiency for removal of β2-microglobulin with 3 different extracorporeal therapies (ETs): high-flux hemodialysis (HF), online hemodiafiltration (OL-HDF), and HDx. The secondary objective was to evaluate the efficiency of removal of other uremic toxins, including urea, phosphate, CRP, IL-6, IL-10, TNF-⍺, indoxyl sulfate, and p-cresol.

METHODS

This single-center, randomized, and cross-over study was performed. Patients were randomized to determine the initial modality of treatment, each period lasted 4 weeks and between one modality and another, there was a washout period of 1 week. Reduction ratios (RRs) of different-size molecules and albumin were calculated for the different ET.

RESULTS

Twenty-two patients were included, β2-microglobulin RR was greater during both OL-HDF and HDx as compared to HF (RR 62% vs. 73% vs. 27%, respectively, p = <0.0001), and there was no significant difference between HDx and OL-HDF (p = 0.09). A decrease in serum phosphate levels was observed in the HDx and OL-HDF periods, contrary to an increase in HF (-0.79 mg/dL vs. -1.02 mg/dL vs. + 0.11 mg/dL, respectively, p = <0.0001). There was no difference in RRs of other molecules (BUN, CRP, IL-6, IL-10, TNF-⍺, indoxyl sulfate, and p-Cresol). There was no decrease in serum albumin in any ET.

CONCLUSION

HDx provides enhanced removal of β2-microglobulin and phosphate as compared to HF, and similar efficacy as with OL-HDF. HDx should be considered an alternative to chronic convective therapies.

Correlation between nerve conduction changes and BETA-2 microglobulin concentration in chronic kidney disease patients on hemodialysis combined with hemodiafiltration online

This study aimed to investigate the correlation between beta-2 microglobulin (B2M) concentration and some nerve conduction indices and evaluate the changes in some nerve conduction indices after treatment with hemodialysis (HD) combined with hemodiafiltration online in end-stage renal disease patients. From July 2021 to July 2022, a cross-sectional study was conducted on 80 end-stage renal disease patients on HD at Can Tho General Hospital, Viet Nam. All the patients had B2M testing and nerve conduction measurements. Patients with nerve conduction disorders were treated and remeasured after 6 months to evaluate the treatment results. At baseline, there was a moderate negative correlation between B2M and the tibial nerve and motor branch of the ulnar conduction velocity (V) (r = -0.305 and -0.315, P < .05). There was a moderate positive correlation between B2M and motor latency of the tibial and peroneal nerve (r = 0.434 and 0.440, P < .05). After 6 months of using the combination of HD and hemodiafiltration online, the V (31.3 ± 7.96 up to 44.88 ± 9.67 m/s) and the amplitude (A) (1.71 ± 1.16 up to 2.61 ± 1.51 mV) of the peroneal nerve increased, the motor latency decreased (8.21 ± 2.65 down to 5.23 ± 3.58 ms). With the tibial nerve, motor conduction V increased from 30.53 ± 8.05 m/s to 43.56 ± 8.99 m/s and the A increased from 5.04 ± 3.16 mV to 7.75 ± 4.45 mV. With the ulnar nerve, the A increased, and motor latency decreased after 6 months. The nerve conduction indices also improved significantly in the median nerve.

High-Flux dialyzer 2.6 m2 is promising for free light chains removal in high-flux hemodialysis and in hemodiafiltration

Immunoglobulin light chains are classified as middle molecule uremic toxins and its removal through effective dialyzer is needed with less albumin loss. This study assessed the free light chains (FLC) removal using dialyzer surface area (SA) 2.6m2 in high-flux dialysis (HF-HD) versus hemodiafiltration (HDF) and its relation to cumulative dialysate albumin loss. This pilot cross-over study included 25 patients who underwent hemodialysis (HD) using dialyzer surface area 2.6m2 on HF-HD followed by online post-dilution HDF with washout period of 2 weeks using high-flux dialyzers (max 2.0 m2 SA). All patients were subjected to single session measurement of dialysate albumin every hour and pre/post dialysis levels of FLC Kappa (Κ) and Lambda (λ) by ELISA. Dialyzer (SA) 2.6m2 showed a significant reduction in post-dialysis kappa and lambda level in comparison to pre-dialysis level on HF-HD and hemodiafiltration (P<0.001). HDF showed higher kappa and lambda FLC reduction ratio (45.16 ± 6.53 %, 28.68 ± 4.36 %, respectively compared to HF-HD (29.52 ± 6.38 %, 19.48 ± 1.96, respectively, P<0.001 for both). Patients on HDF dialysis had significant total albumin loss in dialysate [median (IQR) 2.97; 1.98 - 3.37 gm] compared to HF-HD [median (IQR) 0.67; 0.49 - 1.13 gm] (P <0.001). In conclusion, high-flux dialyzer 2.6 m2 (SA) may be effective in free light chains removal especially with online post-dilution hemodiafiltration with acceptable albumin loss.

Validation of a Protocol for Continuous Hemodiafiltration with Regional Citrate Anticoagulation with Omni®

INTRODUCTION

Omni® (B Braun, Melsungen, Germany) is able to run continuous renal replacement therapy (CRRT) in continuous veno-venous hemofiltration (CVVH), hemodialysis (CVVHD), and hemodiafiltration (CVVHDF) modes. However, to date, there is no validated protocol to guide the use of Omni® in CVVHDF mode with regional citrate anticoagulation (RCA).

METHODS

We designed a protocol for CVVHDF-RCA tailored for Omni®. This protocol was tested in patients included in an observational study conducted in our center between January and March 2021. For all study patients, we collected baseline characteristics, laboratory results, CRRT circuit lifespan as well as plasma and effluent samples at 12, 24, 48, and 72 h of CRRT circuit initiation. At each study time point, we computed urea, creatinine, and β2-microglobulin clearance as well as effluent/blood ratios. Data from circuits in CVVHDF-RCA mode are compared with those in standard therapy (CVVHD-RCA) with the same device.

RESULTS

We analyzed ten circuits (5 patients) in CVVHDF-RCA mode and 32 (13 patients) in CVVHD-RCA mode. No adverse events related to the therapy were observed. In CVVHDF-RCA mode, median circuit running time was 68 (IQR 8.1) hours versus 46 (IQR 9.0) in CVVHD mode, p = 0.053. Therapy adaptations (dialysate rate and/or blood flow) were required in one (10%) circuit (15.6% in CVVHD mode, p = 0.56). Compared to CVVHD, CVVHDF was able to achieve similar clearance and effluent/blood ratio for urea, creatinine, and β2-microglobulin across the entire duration of circuit lifetime.

CONCLUSION

The proposed protocol for CVVHDF-RCA for Omni® was associated with similar circuit lifetime, number of required adaptations and clearances to standard CVVHD-RCA. It appears to be safe and feasible.

[Model selection and curative effect judgment criteria for artificial liver in the treatment of liver failure]

Artificial liver is one of the effective methods to treat liver failure. Patients with liver failure are critically ill and have great individualized differences. Therefore, the specific program for the treatment of liver failure with artificial liver should be individualized. The commonly used non-biological artificial liver models include simple plasmapheresis, double filtration plasmapheresis, plasma filtration with dialysis, double plasma molecular adsorption system, molecular absorbent recirculating system, hemodiafiltration, continuous venovenous hemodiafiltration, hybrid, etc. The curative effect should be properly judged from patient's symptoms, laboratory test indicators, survival rate and other aspects after artificial liver therapy.

Hemodiafiltration Improves Low Levels of Health-Related Quality Of Life (Qol) and Nutritional Conditions of Hemodialysis Patients

We compared the effects on the nutritional condition and health-related quality of life (HR-QoL) of the treatment of patients with on-line hemodiafiltration (OL-HDF) and conventional hemodialysis (CHD) using a superflux dialyzer. In total, 47 maintenance (M) HD patients were treated by CHD with a high-flux dialyzer for the first 4 months (1st CHD) and were then switched to predilution OL-HDF for the next 4 months (OL-HDF), after which CHD was resumed for the last 4 months (2nd CHD). We assessed the clinical parameters, fat mass value, muscle mass value, and HR-QoL. In patients with low serum albumin levels, these levels significantly (p < 0.05) increased in the OL-HDF period. Moreover, the fat mass values significantly (p < 0.05) increased in patients with decreased fat mass values in the OL-HDF period. Although there was no significant difference in the patients with higher scores of physical functioning, role physical, vitality, and social functioning, patients with lower scores in the 1st CHD period had significantly increased (p < 0.05) in the OL-HDF period. In this crossover study, we revealed that OL-HDF treatment significantly improved the nutritional conditions and HR-QoL scores compared with the improvement observed after CHD with a superflux dialyzer, especially for maintenance hemodialysis patients with malnutrition and a low QoL.

A Loading Micafungin Dose in Critically Ill Patients Undergoing Continuous Venovenous Hemofiltration or Continuous Venovenous Hemodiafiltration: A Population Pharmacokinetic Analysis

BACKGROUND

In this study, the authors aimed to compare the pharmacokinetics (PK) of micafungin in critically ill patients receiving continuous venovenous hemofiltration (CVVH, 30 mL·kg-1·h-1) with those of patients receiving equidoses of hemodiafiltration (CVVHDF, 15 mL·kg-1·h-1 + 15 mL·kg-1·h-1) and determine the optimal dosing regimen using the developed model.

METHODS

Patients with septic shock undergoing continuous renal replacement therapy and receiving a conventional dose of 100 mg micafungin once daily were eligible for inclusion. Total micafungin plasma concentrations from 8 CVVH sessions and 8 CVVHDF sessions were subjected to a population PK analysis using Pmetrics. Validation of the model performance was reinforced by external validation. Monte Carlo simulations were performed considering the total ratio of free drug area under the curve (AUC) over 24 hours to the minimum inhibitory concentration (MIC) (AUC0-24/MIC) in plasma.

RESULTS

The median total body weight (min-max) was 94.8 (66-138) kg. Micafungin concentrations were best described by a 2-compartmental PK model. No covariates, including continuous renal replacement therapy modality (CVVH or CVVHDF), were retained in the final model. The mean parameter estimates (SD) were 0.96 (0.32) L/h for clearance and 14.8 (5.3) L for the central compartment volume. External validation confirmed the performance of the developed PK model. Dosing simulations did not support the use of standard 100 mg daily dosing, except for Candida albicans on the second day of therapy. A loading dose of 150 mg followed by 100 mg daily reached the probability of target attainment for all C. albicans and C. glabrata, but not for C. krusei and C. parapsilosis.

CONCLUSIONS

No difference was observed in micafungin PK between equidoses of CVVH and CVVHDF. A loading dose of 150 mg is required to achieve the PK/PD target for less susceptible Candida species from the first day of therapy.

Recent advances in dialysis membranes

PURPOSE OF REVIEW

Improvement in hemodialysis treatment and membrane technology are focused on two aims: the first one is to achieve a better control of circulating uremic solutes by enhancing removal capacity and by broadening molecular weight spectrum of solutes cleared; the second one is to prevent inflammation by improving hemocompatibility of the global dialysis system.

RECENT FINDINGS

Despite impressive progresses in polymers chemistry few hazards are still remaining associated with leaching or sensitization to polymer additives. Research has focused on developing more stable polymers by means of additives or processes aiming to minimize such risks. Membrane engineering manufacturing with support of nanocontrolled spinning technology has opened up membrane to middle and large molecular weight substances, while preserving albumin losses. Combination of diffusive and enhanced convective fluxes in the same hemodialyzer module, namely hemodiafiltration, provides today the highest solute removal capacity over a broad spectrum of solutes.

SUMMARY

Dialysis membrane is a crucial component of the hemodialysis system to optimize solute removal efficacy and to minimize blood membrane biological reactions. Hemodialyzer is much more than a membrane. Dialysis membrane and hemodialyzer choice are parts of a treatment chain that should be operated in optimized conditions and adjusted to patient needs and tolerance, to improve patient outcomes.

Pilot study to investigate differences in middle molecules, oxidative stress and markers of peripheral vascular disease in patients treated by high flux haemodialysis and haemodiafiltration

Background

Dialysis patients have an increased risk of mortality. Recently treatment with haemodiafiltration (HDF) has been reported to reduce mortality, particularly cardiovascular mortality, compared to standard high-flux haemodialysis (HD). However, why HDF may offer a survival advantage remains to be determined. So, we conducted a pilot study to explore differences in middle-molecules, inflammation and markers of vascular disease in patients treated by HD and HDF.

Methods

Observational cross-sectional study measuring serum β2-microglobulin (β2M), Advanced Glycosylation End Products (AGEs) by skin autofluorescence (SAF), oxidative stress with ischaemia modified albumin ratio (IMAR) and peripheral vascular disease assessment using Ankle-Brachial Index (ABI), and arterial stiffness using Cardio-Ankle Vascular Index (CAVI).

Results

We studied 196 patients, mean age 69.1 ± 12.4 years, 172 (87.8%) treated by HD and 24 (12.2%) by HDF. Age, body mass index, co-morbidity and dialysis vintage were not different between HD and HDF groups. Middle molecules; β₂M (31±9.9 vs 31.2±10 ug/mL) and SAF (2.99±0.72 vs 3.0±0.84 AU), ABI (1.06±0.05 vs 1.07±0.10) and CAVI (9.34±1.55 vs 9.35±1.23) were not different, but IMAR was higher in the HD patients (38.4±14.8 vs 31.3 ± 17.4, P = 0.035)

Conclusions

In this pilot observational study, we found patients treated by HDF had lower oxidative stress as measured by IMAR, with no differences in middle molecules. Lower oxidative stress would be expected to have diverse protective effects on the cardiovascular system Although we found no differences in ABI and CAVI, future studies are required to determine whether reduced oxidative stress translates into clinically relevant differences over time.

Status of Four Trace Elements in Elderly Patients with Online Hemodiafiltration

BACKGROUND

Essential trace elements play key roles in multiple biological systems, and hemodialysis patients are at risk for deficiency of essential trace elements. The aim of the study was to assess the essential element status in end stage renal disease patients undergoing online hemodiafiltration (online HDF) in outpatient dialysis clinic.

METHODS

A total of 28 Korean patients with regular online HDF were included. Blood samples were collected before and after one HDF session, and serum concentrations of zinc, copper, selenium, and manganese were simulta-neously measured by inductively coupled plasma mass spectrometry.

RESULTS

Selenium, zinc, copper deficiencies were observed in 71.4%, 35.8%, and 21.4%, compared with the reference range. No patients revealed manganese deficiency. After the HDF, the post-HDF level significantly increased in all trace elements, compared with the pre-HDF (11.2% for selenium, 10.7% for copper, and 6.6% for zinc). However, 50% patients were still deficient for selenium at the post-HDF.

CONCLUSIONS

Our data suggest that the patients undergoing online HDF are at an increased risk of trace element deficiency, especially for selenium.

Vancomycin Intoxication and Cefepime-induced Encephalopathy Treated by Abdominal Drainage of Massive Ascites in Addition to Online Hemodiafiltration

A patient with recurrent plasmacytoma with massive ascites exhibited vancomycin intoxication and cefepime-induced encephalopathy due to renal dysfunction. The ascitic accumulation of these drugs was suspected because of the refractory intoxicated state. To remove these drugs that had accumulated in the blood and ascites, abdominal drainage was performed in addition to online hemodiafiltration. If patients with renal dysfunction and massive ascites develop vancomycin intoxication and cefepime-induced encephalopathy that cannot be improved by drug discontinuation, physicians should suspect ascitic accumulation and evaluate the ascitic concentration. Furthermore, if a high accumulation in massive ascites occurs, physicians should perform abdominal drainage along with blood purification.

Building a hemodiafiltration system from readily available components for continuous renal replacement therapy under disasters and pandemics: preparing for an acute kidney injury surge during COVID-19

PURPOSE OF REVIEW

The novel corona virus (SARS-CoV2) has been demonstrated to cause acute kidney injury due to direct cellular toxicity as well as due to a variety of autoimmune glomerular diseases. The concept of a surge of infected patients resulting in an overwhelming number of critical patients has been a central concern in healthcare planning during the COVID-19 era.

RECENT FINDINGS

One crucial question remains as to how to manage patients with end stage renal disease and acute kidney injury in case of a massive surge of critically ill infected patients. Some publications address practical and ingenious solutions for just such a surge of need for renal replacement therapy. We present a plan for using a blood pump, readily available dialysis filter, and a prefilter and postfilter replacement fluid set up. This is in conjunction with multiple intravenous pumps to develop a simple hemofiltration apparatus.

SUMMARY

The current set up may be a readily available option for use in critical situations where the need for renal replacement therapy outstrips the capacity of traditional hemodialysis services in a hospital or region.

Single Lumen Alternating Micro-Batch Hemodiafiltration (SLAMB-HDF): A Device for Minimally Invasive Renal Replacement Therapy

Blood-based RRT, such as hemodialysis, requires access to the bloodstream and adequate blood flow to enable the requisite clearance. As such, nearly all RRT systems require two lumens, enabling a blood circuit that pulls blood from one lumen or needle and returns it via another lumen or needle. The proposed single lumen alternating micro-batch (SLAMB) technique uses a small single lumen to draw a "micro" batch of blood into a single reservoir. In the reservoir, the "batch" of blood is circulated at a high blood flow rate through a hemofilter or hemodialyzer, enabling efficient small- and middle-molecule clearance. Thereafter, the "purified" blood is returned to the patient and the cycle is repeated. Each batch comprises 20-300 ml of blood, which is adjusted to the vascular access, hemodynamic status, and size of the patient. Up to 15 cycles can be done per hour, allowing this system to achieve a blood clearance level comparable to modern continuous RRT systems. Because the system can function with a small-bore single lumen, this device can work with existing central lines, thus allowing for less invasive vascular access. Because of their size and relative simplicity, SLAMB-based systems are less expensive, smaller, and have improved portability. Lastly, a similar, manual SLAMB-hemofiltration kit, which requires no electricity or battery, can be developed at low cost (<$25) for use in austere medical conditions, thus expanding the availability of RRT for patients with AKI.

How to rescue high-dose methotrexate induced nephrotoxicity and literature review about hemodiafiltration?

Methotrexate (MTX) is a highly renal and liver toxicity drug used in hematological malignancy treatment in children and adults. High-dose methotrexate (HD-MTX) therapy may cause impairment of kidney and decrease the elimination of MTX, at the same time, the serum concentration of MTX increased. Today the treatment for preventing MTX toxicity after renal shutdown is Carboxypeptidase. We report a patient who experienced nephrotoxicity after the HD-MTX infusions during the treatment for non-Hodgkin lymphoma (NHL) and received hemodiafiltration (HDF) with large dose of leucovorin (LV) to treat MTX intoxication. LV is very potent in the prevention of neurotoxicity and administration of LV could protect the normal cells, but the dosage and duration of LV should be according to the MTX concentration. Although a large dose of LV was applied, the patient's condition did not improve. It was found that the HDF with large dose of LV to save the patient and steadily improved the patient's clinical condition.

Mixed hemodiafiltration reduces erythropoiesis stimulating agents requirement in dialysis patients: a prospective randomized study

BACKGROUND

Improved responsiveness to erythropoiesis stimulating agents (ESAs) in patients on on-line post-dilution hemodiafiltration (Post-HDF) compared with conventional hemodialysis (HD) was reported by some authors but challenged by others. This prospective, cross-over randomized study tested the hypothesis that an alternative infusion modality of HDF, mixed-dilution HDF (Mixed HDF), could further reduce ESAs requirement in dialysis patients compared to the traditional Post-HDF.

METHODS

One-hundred-twenty prevalent patients from 6 Dialysis Centers were randomly assigned to two six-months treatment sequences: A-B and B-A (A, Mixed HDF; B, Post-HDF). Primary outcome was comparative evaluation of ESA (darbepoetin alfa) requirement and ESA resistance. Treatments efficiency, iron and vitamins status, inflammation and nutrition parameters were monitored.

RESULTS

In sequence A, darbepoetin requirement decreased during Mixed HDF from 29.5 to 23.7 µg/month and increased significantly during Post-HDF (32.3 µg/month at 6th month) while, in sequence B, it increased during Post-HDF from 38.2 to 43.7 µg/month and decreased during Mixed HDF (23.9 µg/month at 6th month). Overall, EPO doses at 6 months on Mixed and Post-HDF were 23.8 and 38.4 µg/month, respectively, P < 0.01. A multiple linear model confirmed that Mixed HDF vs Post-HDF reduced significantly ESA requirement and ESA resistance (P < 0.0001), by a mean of 29% (CI 23-35%) in the last three months of the observation periods.

CONCLUSIONS

Mixed HDF decreased darbepoetin-alfa requirement in dialysis patients. This might help preventing the untoward side effects of high ESA doses, besides having a remarkable economic impact. Additional evidence is needed to confirm this potential benefit of Mixed-HDF.

Improved Outcomes in Hemodialysis/Hemodiafiltration Treatments Applying Exercise and Physiological Monitoring Techniques: Preliminary Results

End-stage renal disease affects millions of people worldwide, and the only definitive solutions are renal transplants that are not widely available. Temporary solutions are renal replacement therapies such as peritoneal dialysis, hemodialysis and hemodiafiltration. These therapies as they are applied today are just partial measures and have many drawbacks and complications such as high mortality rates and high costs due to the use of supplemental drugs and emergency room visits. Many enhancements to the therapies have been published, but they are not applied consistently in real world practice. Our work presents the results from the systematic application of several techniques to provide individualized therapies that can minimize the drawbacks and improve patient outcomes. This approach is based on the use of exercise, analysis of cardiovascular parameters, such as heart-rate variability, body composition and dry weight measurements through the use of bioimpedance and real-time monitoring of energy expenditure and nutrition intradialytically in order to provide individualized and dynamically variable therapies. Results show that patients can lead long, productive lives while maintaining a quality of life equivalent to that of a renal transplant.

Effect of Ultrafiltration on Sleep Apnea and Cardiac Function in End-Stage Renal Disease

RATIONALE

End-stage renal disease (ESRD) patients have high annual mortality mainly due to cardiovascular causes. The acute effects of obstructive and central sleep apnea on cardiac function in ESRD patients have not been determined. We therefore tested, in patients with ESRD, the hypotheses that (1) sleep apnea induces deterioration in cardiac function overnight and (2) attenuation of sleep apnea severity by ultrafiltration (UF) attenuates this deterioration.

METHODS

At baseline, ESRD patients, on conventional hemodialysis, with left ventricular ejection fraction (LVEF) >45% had polysomnography (PSG) performed on a non-dialysis day to determine the apnea-hypopnea index (AHI). Echocardiography was performed at the bedside, before and after sleep. Isovolumetric contraction time divided by left ventricular ejection time (IVCT/ET) and isovolumetric relaxation time divided by ET (IVRT/ET) were measured by tissue doppler imaging. The myocardial performance index (MPI), a composite of systolic and diastolic function was also calculated. One week later, subjects with sleep apnea (AHI ≥15) had fluid removed by UF, followed by repeat PSG and echocardiography. -Results: Fifteen subjects had baseline measurements, of which 7 had an AHI <15 (no-sleep-apnea group) and 8 had an AHI ≥15 (sleep-apnea group). At baseline, there was no overnight change in the LVEF in either the no-sleep-apnea group or the sleep-apnea group. In the no-sleep-apnea group, there was also no overnight change in MPI, IVCT/ET and IVRT/ET. However, in the sleep-apnea group there were overnight increases in MPI, IVCT/ET and IVRT/ET (p = 0.008, 0.007 and 0.031, respectively), indicating deterioration in systolic and diastolic function. Following fluid removal by UF in the sleep-apnea group, the AHI decreased by 48.7% (p = 0.012) and overnight increases in MPI, IVCT/ET and IVRT/ET observed at baseline were abolished.

CONCLUSIONS

In ESRD, cardiac function deteriorates overnight in those with sleep apnea, but not in those without sleep apnea. This overnight deterioration in the sleep-apnea group may be at least partially due to sleep apnea, since attenuation of sleep apnea by UF was accompanied by elimination of this deleterious overnight effect.

Vitamin e-loaded membrane dialyzers reduce hemodialysis inflammaging

BACKGROUND

Inflammaging is a persistent, low-grade, sterile, nonresolving inflammatory state, associated with the senescence of the immune system. Such condition downregulates both innate and adaptive immune responses during chronic disorders as type II diabetes, cancer and hemodialysis, accounting for their susceptibility to infections, malignancy and resistance to vaccination. Aim of this study was to investigate hemodialysis inflammaging, by evaluating changes of several hemodialysis treatments on indoleamine 2,3-dioxygenase-1 activity and nitric oxide formation.

METHODS

We conducted a randomized controlled observational crossover trial. Eighteen hemodialysis patients were treated with 3 different hemodialysis procedures respectively: 1) Low-flux bicarbonate hemodialysis, 2) Low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers, and 3) Hemodialfitration. The control group consisted of 14 hospital staff healthy volunteers. Blood samples were collected from all 18 hemodialysis patients just after the long interdialytic interval, at the end of each hemodialysis treatment period.

RESULTS

Hemodialysis kynurenine and kynurenine/L - tryptophan blood ratio levels were significantly higher, when compared to the control group, indicating an increased indoleamine 2,3-dioxygenase-1 activity in hemodialysis patients. At the end of the low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers period, L - tryptophan serum levels remained unchanged vs both low-flux bicarbonate hemodialysis and hemodialfitration. Kynurenine levels instead decreased, resulting in a significant reduction of kynurenine/L - tryptophan blood ratio and indoleamine 2,3-dioxygenase-1 activity, when matched to both low-flux bicarbonate hemodialysis and HDF respectively. Serum nitric oxide control group levels, were significantly lower when compared to all hemodialysis patient groups. Interestingly, low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers nitric oxide serum levels from venous line blood samples taken 60 min after starting the hemodialysis session were significantly lower vs serum taken simultaneously from the arterial blood line.

CONCLUSIONS

The treatment with more biocompatible hemodialysis procedure as low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers, reduced indoleamine 2,3-dioxygenase-1 activity and nitric oxide formation when compared to both low-flux bicarbonate hemodialysis and hemodialfitration. These data suggest that low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers lowering hemodialysis inflammaging, could be associated to changes of proinflammatory signalling a regulated molecular level.

TRIAL REGISTRATION

NCT Number: NCT02981992; Other Study ID Numbers: 20100014090. First submitted: November 26, 2016. First posted: December 5, 2016. Last Update Posted: December 5, 2016.

Comparative Evaluation of Continuous Veno-venous Hemodiafiltration and Continuous Arterio-Venous Hemodiafiltration in Patients of Hepatic Failure and / or Hepatorenal Syndrome

OBJECTIVES

Continuous renal replacement therapies (CRRT) are the most favoured form of renal replacement therapies (RRT) in patients of decompensated liver cirrhosis and hepatorenal syndrome (HRS). The role of CRRT has been limited only to acute kidney injury and HRS in prior studies. We therefore aimed to evaluate the role of two different modes of CRRT- CVVHDF and CAVHDF in patients of hepatic failure and / or hepatorenal syndrome in reducing hyperbilirubinemia, uremia and fluid overload.

METHODS

30 critically ill patients of hepatic failure and /or HRS were randomly divided into two groups of 15 cases each. Group A patients received continuous veno-venous hemodiafiltration (CVVHDF), whereas group B patients underwent continuous arterio-venous hemodiafiltration (CAVHDF). The inclusion criteria were hepatic failure and / or hepatorenal syndrome (HRS) with hyperbilirubinemia and fluid overload in hemodynamically unstable patients, who were unfit for conventional hemodialysis.

RESULTS

Despite hemodynamic fragility of the subjects, both the procedures were effective in achieving biochemical and clinical improvements. There was a significant fall in blood urea, serum creatinine and serum bilirubin at the end of procedures. After mean 27.32 h of CVVHDF and 27.02 h of CAVHDF, blood urea decreased to 39.54 ± 28.6 mg/dl and 45.11 ± 31.9 mg/dl in respective groups. Serum bilirubin decreased to 7.01 ± 6.4 mg/dl and 3.21 ± 1.99 mg/dl in group A and B. All the patients had gradual and steady improvement in pH and bicarbonate concentration towards normal. Urea clearance was 24.98 ± 1.09 ml/min and 22.72 ± 1.58 ml/min respectively in the two groups, whereas bilirubin clearance was 27.77 ± 1.38 ml/min and 28.74 ± 0.3 ml/min in group A and B respectively. Ultrafiltration rate had mean value of 141.66 ± 22.33 ml/h in group A and 134.26 ± 38.71 ml/h in group B. Both the modes of CRRT were well tolerated without any new episodes of hypotension secondary to the procedures and requirement of inotropes didn't change significantly. Symptomatic relief and improvement in clinical and biochemical parameters were observed in all the cases. There were no significant differences between the results of two groups. Complication rate was less and survival was 30%.

CONCLUSION

Continuous hemodiafiltration is probably the best available modality of CRRT to treat hemodynamically unstable and critically ill patients of hepatic failure and/ or hepatorenal syndrome and it should be advocated more frequently.

[Acetate-free Biofiltration: CO2-free treatment for hemodialysis patients with hypercapnia]

In bicarbonate-dialysis the dialysate is acid, thus allowing salts to remain in their soluble form, as a result of the chemical reaction of bicarbonate with any acid that yields carbon dioxide (CO2). The residual anion, commonly acetate or more rarely citrate, reaches the patients' bloodstream. CO2 also spreads to the patients and ventilation needs therefore to be increased to avoid hypercapnia. In addition, during on-line haemodiafiltration in post-dilution mode, the dialysate - in the form of infusate - carries CO2 (and acetate) to the patient, bypassing the filtering membrane. On the contrary, in Acetate-Free Biofiltration (AFB) the dialysate is free of acid and, uniquely, is also a CO2-free bath. Despite the infusion of bicarbonate in post-dilution mode, the blood coming back from the extracorporeal circuit does not carry any burden of CO2. As a result, AFB is the recommended renal replacement therapy for patients affected by lung disease and those with CO2 retention (respiratory acidosis). Patients with some degree of ventilatory dysfunction may in fact experience acute hypercapnia (acidosis by dialysate) at the beginning of the treatment if bicarbonate-dialysis or on-line HDF is performed (and regardless of whether acetate-containing or citrate-containing bath is employed). Acidosis by dialysate is characterized by respiratory symptoms first and by haemodynamic instability later, which make it look very similar to acetate intolerance. To discriminate between these two conditions, blood gas analysis is mandatory. The presence of hypercapnia can be revealed by using the Very Simple Formula (expected pCO2 = bicarbonate + 15), thus identifying those patients that may take the most advantage of AFB.

Effects of high-volume online mixed-hemodiafiltration on anemia management in dialysis patients

Background

Anemia is a major comorbidity of patients with end-stage renal disease and poses an enormous economic burden to health-care systems. High dose erythropoiesis-stimulating agents (ESAs) have been associated with unfavorable clinical outcomes. We explored whether mixed-dilution hemodiafiltration (Mixed-HDF), based on its innovative substitution modality, may improve anemia outcomes compared to the traditional post-dilution hemodiafiltration (Post-HDF).

Methods

We included 174 adult prevalent dialysis patients (87 on Mixed-HDF, 87 on Post-HDF) treated in 24 NephroCare dialysis centers between January 2010 and August 2016 into this retrospective cohort study. All patients were dialyzed three times per week and had fistula/graft as vascular access. Patients were matched at baseline and followed over a one-year period. The courses of hemoglobin levels (Hb) and monthly ESA consumption were compared between the two groups with linear mixed models.

Results

Mean baseline Hb was 11.9±1.3 and 11.8±1.1g/dl in patients on Mixed- and Post-HDF, respectively. While Hb remained stable in patients on Mixed-HDF, it decreased slightly in patients on Post-HDF (at month 12: 11.8±1.2 vs 11.1±1.2g/dl). This tendency was confirmed by our linear mixed model (p = 0.0514 for treatment x time interaction). Baseline median ESA consumption was 6000 [Q1:0;Q3:16000] IU/4 weeks in both groups. Throughout the observation period ESA doses tended to be lower in the Mixed-HDF group (4000 [Q1:0;Q3:16000] vs 8000 [Q1:0;Q3:20000] IU/4 weeks at month 12; p = 0.0791 for treatment x time interaction). Sensitivity analyses, adjusting for differences not covered by matching at baseline, strengthened our results (Hb: p = 0.0124; ESA: p = 0.0687).

Conclusions

Results of our explorative study suggest that patients on Mixed-HDF may have clinical benefits in terms of anemia management. This may also have a beneficial economic impact. Future studies are needed to confirm our hypothesis-generating results and to provide additional evidence on the potential beneficial effects of Mixed-HDF.

Effect of online hemodiafiltration compared with hemodialysis on quality of life in patients with ESRD: A systematic review and meta-analysis of randomized trials

Background

End-stage renal disease (ESRD) is related to high morbidity, mortality, and impaired health-related quality of life. While hemodialysis (HD) is the current life-saving standard of treatment for patients with ESRD, their quality of life (QoL) remains far from desirable. Online HDF (OL-HDF), due to its convenience, could improve the QoL of patients with ESRD, however, this remains uncertain.

Objective

We aimed to assess the body of evidence of OL-HDF compared to HD regarding QoL in patients with ESRD.

Methods

We comprehensively searched in multiple data bases from their inception to February 2018. Reviewers working independently and in duplicate appraised the quality and included randomized controlled trials (RCTs) that evaluated, in patients with ESRD and HD or OL-HDF, QoL (Short Form Health Survey with 36 questions (SF-36) with physical component score (PCS) and mental component score (MCS) as well as scores about social activity, fatigue, and emotion). A meta-analysis of each outcome of interest was performed using a random-effects model.

Results

Six moderate quality RCTs met the inclusion criteria. Meta-analysis of 4 RCTs including a total of 1,209 patients showed that OL-HDF was associated with a lower yet non-significant score of PCS: MD (mean difference) -0.77 (95% CI -1.94 to 0.41, p = 0.20), and MCS: MD -1.25 (95% CI -3.10 to 0.59, p = 0.18); indicating a poorer QoL in patients on OL-HDF. Meta-analysis of 4 RCTs including a total of 845 patients showed OL-HDF was associated with a significant increase in the score of social activity compared to HD: SMD (standardized mean difference): 1.95 (95% CI 0.05 to 3.86, p = 0.04), indicating a better QoL in patients on OL-HDF; but regarding fatigue and emotion, there was no significant improvement when compared to HD by meta-analysis of 3 RCTs (133 patients).

Conclusions

The body of evidence suggests that OL-HDF does not improve QoL in patients with ESRD when compared to HD.

Acid base variables predict survival early in the course of treatment with continuous venovenous hemodiafiltration

Metabolic acid-base disorders, especially metabolic acidosis, are common in critically ill patients who require renal replacement therapy. Continuous veno-venous hemodiafiltration (CVVHDF) achieves profound changes in acid-base status, but metabolic acidosis can remain unchanged or even deteriorate in some patients. The objective of this study is to understand the changes of acid-base variables in critically ill patients with septic associated acute kidney injury (SA-AKI) during CVVHDF and to determine how they relate to clinical outcome.Observational study of 200 subjects with SA-AKI treated with CVVHDF for at least 72 hours. Arterial blood gases and electrolytes and other relevant acid-base variables were analyzed using quantitative acid-base chemistry.Survivors and nonsurvivors had similar demographic characteristics and acid-base variables on day one of CVVHDF. However, during the next 48 hours, the resolution of acidosis was significantly different between the 2 groups, with an area under the ROC curve for standard base excess (SBE) and mortality of 0.62 (0.54-0.70), this was better than APACHE II score prediction power. Quantitative physicochemical analysis revealed that the majority of the change in SBE was due to changes in Cl and Na concentrations.Survivors of SA-AKI treated with CVVHDF recover hyperchloremic metabolic acidosis more rapidly than nonsurvivors. Further study is needed to determine if survival can be improved by measures to correct acidosis more rapidly.

[A case of severe metformin-associated lactic acidosis treated with CVVHDF and regional anticoagulation with sodium citrate]

Metformin is an antidiabetic drug; used to treat type II diabetes mellitus, metformin associated lactic acidosis has an incidence of 2-9 cases / 100,000 patients / year with high mortality (30%). We have had the case of a 75-year-old woman with metabolic acidosis as a result of metformin assumption, treated by renal replacement therapy (CRRT) with continuous veno-venous hemodiafiltration (CVVHDF).

RESULTS

after a short treatment period there was a reduction in Lactates (from 16.8 mmol/L to 12.6 mmol/L) and a progressive improvement of acidosis. In 72 hours the recovery of diuresis and subsequent suspension of CRRT was achieved.

CONCLUSION

CRRT, in addition to ensuring support for renal failure and volume correction, allowed a rapid recovery from metformin-associated lactic acidosis.

High-volume continuous venovenous hemodiafiltration plus resin hemoperfusion improves severe metformin-associated toxicity

We present the case of a 42-year-old female patient who attempted suicide by taking approximately 100 tablets of metformin (500 mg). Laboratory tests revealed severe lactic acidosis with lactate levels of 24 mmol/L and pH of 7.09. The patient was treated with high-volume continuous venovenous hemodiafiltration (CVVH) and resin-sorbent hemoperfusion. Metformin concentrations were measured by high-performance liquid chromatography during CVVH and hemoperfusion treatment. Before extracorporeal treatment, the plasma metformin concentration was 208.5 mg/L. After CVVH treatment for 24 h, the plasma metformin concentration had decreased to 13.9 mg/L. Resin-based sorbent hemoperfusion plus CVVH treatment had reduced the metformin plasma concentration by 61.8% after 3 h. After 7 days, the patient's laboratory tests and clinical syndrome were improved, and she was discharged from hospital. We provide evidence that CVVH plus hemoperfusion is effective in eliminating metformins and metabolic products.

Soluble Toll-like Receptor 4: A New Player in Subclinical Inflammation and Malnutrition in Hemodialysis Patients

OBJECTIVE

Toll-like receptor 4 (TLR4) promotes inflammation in hemodialysis patients (HD). A soluble form of extracellular TLR4 (sTLR4) has been recently characterized, which showed the ability to attenuate TLR4 signalling. In this study, we describe the sTLR4 profile in regular HD patients.

SUBJECTS

In a cross-sectional study we enrolled forty prevalent HD patients (68.2 ± 16.3 years, twenty-five males) with a median dialysis vintage of 41 months. Nineteen patients were undergoing standard bicarbonate HD (BHD) and 21 patients on-line hemodiafiltration (HDF). Ten healthy sex-matched subjects constituted the controls (C).

INTERVENTION

Before and after the HD session, serum was tested for sTLR4 levels by ELISA. Moreover, clinical and biochemical data were collected, including body mass index, albumin, and C-reactive protein (CRP) levels. Body composition was expressed as a 3-compartment model, providing lean tissue index and fat tissue index (FTI).

MAIN OUTCOME MEASURE

Describe the profile of sTLR4 in HD patients, evaluating the correlations among sTLR4 levels and the main clinical characteristics, inflammatory and nutritional parameters.

RESULTS

Patients with subclinical inflammation (i.e., high CRP levels without clinical symptomatology) presented higher sTLR4 levels (0.42 ± 0.25 ng/mL) with respect to both C and not inflamed HD patients (0.23 ± 0.19 ng/mL, P < .05). There was a significant direct correlation between predialysis sTLR4 and body mass index, FTI (r = 0.55), and CRP levels (r = 0.52) and inverse correlation with lean tissue index and albumin (r = -0.4). In multivariate analysis, sTLR4 resulted directly associated with FTI (P = .038). Notably, sTLR4 levels resulted higher in bicarbonate hemodialysis versus hemodiafiltration (0.37 ± 0.18 vs. 0.19 ± 0.21 ng/mL, P < .05).

CONCLUSIONS

sTLR4 correlates with inflammatory and nutritional parameters, presenting as a new potential player in modulating subclinical inflammation in HD patients.

[Severe lactic acidosis requiring continuos haemodiafiltration in a young patient with unrecognized metabolic abnormality. Case report]

BACKGROUND

Lactic acidosis (LA) is the most common form of metabolic acidosis, defined by lactate values greater than 5 mmol/L and pH<7.34. The pathogenesis of LA involves hypoxic causes (type A) and non-hypoxic (type B), often coexisting. Identification and removal of the trigger are mandatory in the therapeutic management of LA. The case: A 38 years-old male patient entered the Emergency Ward for dyspnea, fever, vomiting and hyporexia. An important respiratory distress with hyperventilation due to severe LA was found, together with severe hypoglicemia, without renal impairment. Past medical history unremarkable, except for reported episodic hypoglicemia in the childhood, with fructose "intolerance", without any other data. No evidence of intoxications, septic shock or significant cytolysis. No drugs causing LA. The patient underwent orotracheal intubation, glucose infusion, and continuous haemodiafiltration for 36-hrs. A rapid general improvement was obtained with stabilization of acid-base balance. A diagnosis of fructose-1,6-diphosphatase deficiency was made. It is an autosomical recessive gluconeogenesis abnormality, with recurrent episodes of hypoglicemia and lactic acidosis after fasting, potentially lethal. The therapy is based on avoiding prolonged fasts, glucose infusion, and a specific diet, rich in glucose without fructose intake.

CONCLUSIONS

The presence of not-otherwise-explained lactic acidosis in young patients has to place the suspect of an underlying and unknown metabolic derangement; in these cases, the involvement of the nephrologist appears to be pivotal for the differential diagnosis of the abnormalities of the acid-base balance, and for setting the best treatment.