A randomized cross-over study with objective quantification of the performance of an asymmetric triacetate and a polysulfone dialysis membrane using different anticoagulation strategies

Detection and Scoring of Extracorporeal Circuit Clotting During Hemodialysis

Maintaining patency of the extracorporeal hemodialysis (HD) circuit is a prerequisite to perform HD. Unfractionated heparin and low-molecular-weight heparins are the most used anticoagulants in maintenance HD, but their administration comes with a major trade-off of bleeding complications. This narrative review article discusses technical factors impacting on HD circuit patency, such as tubings, dialyzer membranes, priming practices, and treatment settings. Strategies for monitoring extracorporeal circuit clotting during and after treatment are also reviewed, as these are essential tools for optimizing anticoagulation.

Association between anticoagulation strategy and quality of life in chronic hemodialysis patients

Prevention of clotting in hemodialysis (HD) is a concern, but tools to monitor anticoagulation strategies as well as data on bleeding and its impact on quality of life (QoL) are scant. In this prospective longitudinal observational study, bleeding tendency in 70 HD patients was scored with ISTH-BAT and HAS-BLED at week 0, 4, and 8. Patient's limbs were visually scored for bruises and hematomas, and Quality of Life (QoL) was assessed using EQ5D-3L and Visual Analogue Scale (VAS) questionnaires. At week 0, the used hemodialyzer was scanned in a micro-CT scanner to quantify the number of patent fibers. Bleeding scores were 0 [0; 1] and 3 [2; 4] for ISTH-BAT and HAS-BLED, and visual scoring showed 2 [0; 4] bruises/hematomas. QoL was 0.85 [0.77; 1.00] for EQ5D and 70 [60; 80] for VAS. Fiber patency was 81 [70; 90]%, but was not associated with anticoagulation dose (p = 0.103). Patients in the highest tertile of anticoagulation dose had a worse VAS score (p = 0.027), and patients identified as having bleeding tendency by ISTH also had a worse VAS score (p = 0.010). This supports our postulate that in maintenance HD patients the current personal anticoagulation dose regimens may be too high, leading to more mainly minor bleeding that may negatively impact health related quality of life.

Standardization of Nomenclature for the Mechanisms and Materials Utilized for Extracorporeal Blood Purification

In order to develop a standardized nomenclature for the mechanisms and materials utilized during extracorporeal blood purification, a consensus expert conference was convened in November 2022. Standardized nomenclature serves as a common language for reporting research findings, new device development, and education. It is also critically important to support patient safety, allow comparisons between techniques, materials, and devices, and be essential for defining and naming innovative technologies and classifying devices for regulatory approval. The multidisciplinary conference developed detailed descriptions of the performance characteristics of devices (membranes, filters, and sorbents), solute and fluid transport mechanisms, flow parameters, and methods of treatment evaluation. In addition, nomenclature for adsorptive blood purification techniques was proposed. This report summarizes these activities and highlights the need for standardization of nomenclature in the future to harmonize research, education, and innovation in extracorporeal blood purification therapies.

Assessment of the Influence of Asymmetric Triacetate Cellulose Membrane on the Rate of Removal of Middle Molecular Weight Uremic Toxins in Patients Treated with Postdilution Online Hemodiafiltration

BACKGROUND: Postdilution online hemodiafiltration (OL-HDF) effectively removes uremic toxins of middle molecular weight from the blood of patients with end-stage chronic kidney disease. The rate of removal of uremic toxins depends on the type of dialysis membrane, blood flow rate (Qb), net ultrafiltration flow rate (Qnuf), and total convective volume (Vconv). AIM: The aim of this study was to examine the efficacy of asymmetric triacetate cellulose dialysis membrane in patients on post-dilution OL-HDF. METHODS: Thirty-five patients treated with post-dilution OL-HDF hemodiafiltration for at least 3 months were examined. The main parameters for assessing the efficiency of removal of uremic toxins of middle molecular weight are the concentration of β2-microglobulin (β2-M) and interleukin-6 (IL-6) in serum before and after a single session of post-dilution OL-HDF. The followings were used for statistical analysis: Kolmogorov–Smirnov test, Student’s T test for bound samples and Wilcoxon test. RESULTS: The average Vconv was 20.90 ± 3.30 liters/session. The β2-M reduction index during a single session of postdilution OL-HDF was 71.10 ± 6.39%, the IL-6 reduction index was 43.75 ± 15.60%, and the albumin reduction index was 4.55 ± 2.31%. CONCLUSION: The asymmetric triacetate cellulose dialysis membrane effectively removes β2-M and IL-6 during a single session of postdilution OL-HDF. The β2-M reduction index is ∼70%, the IL-6 reduction index is ∼40%, and albumin loss is <4.0 g/4 h. The examined dialysis membrane and dialysis modality prevent the development of amyloidosis associated with dialysis, microinflammation and reduce the risk of developing atherosclerotic cardiovascular diseases in the population of patients treated with regular hemodiafiltration.

Impact of intradialytic fiber clotting on dialyzer extraction and solute removal: a randomized cross-over study

Previous studies revealed the importance of biocompatibility, anticoagulation strategy, and dialysis mode and duration on fiber blocking at the end of a hemodialysis session. The present study was set up in ten hemodialysis patients to relate fiber patency to dialyzer extraction and removal of small and middle molecules. With only 1/4th of the regular anticoagulation dose, and using a Solacea 19H and FX800 CorDiax dialyzer, fiber patency was quantified using 3D micro-CT scanning for different dialysis durations (i.e. 60, 120 and 240 min). While Solacea showed enhanced fiber patency in all test sessions, fiber blocking in the FX800 CorDiax did not follow a linear process during dialysis, but was rather accelerated near the end of dialysis. Dialyzer extraction ratios were correlated with the percentages of open fibers. While the fiber blocking process affected extraction ratios (i.e. for phosphorus and myoglobin in the FX800 CorDiax), it had only minor impact on the removal of toxins up to at least 12 kDa.

Biocompatibility of Surface-Modified Membranes for Chronic Hemodialysis Therapy

Hemodialysis is a life-sustaining therapy for millions of people worldwide. However, despite considerable technical and scientific improvements, results are still not fully satisfactory in terms of morbidity and mortality. The membrane contained in the hemodialyzer is undoubtedly the main determinant of the success and quality of hemodialysis therapy. Membrane properties influence solute removal and the interactions with blood components that define the membrane’s biocompatibility. Bioincompatibility is considered a potential contributor to several uremic complications. Thus, the development of more biocompatible polymers used as hemodialyzer membrane is of utmost importance for improving results and clinical patient outcomes. Many different surface-modified membranes for hemodialysis have been manufactured over recent years by varying approaches in the attempt to minimize blood incompatibility. Their main characteristics and clinical results in hemodialysis patients were reviewed in the present article.