2011 JSDT Standard on the Management of Endotoxin Retentive Filter for Dialysis and Related Therapies

Effectiveness of combination of heat water disinfection, continuous water circulation, and minimalized dead space for dialysis piping in maintaining ultrapure dialysis fluid and preventing biofilm formation in a central dialysis fluid delivery system

Various benefits have been attached to purifying the dialysis fluid used for hemodialysis therapy. The central dialysis fluid delivery system can treat approximately 50 dialysis patients simultaneously and is convenient to operate. In contrast, the dialysis fluid supply piping is complicated, and bacterial growth can cause biofilms. This study aimed to develop sustainable cleaning strategies to solve the complicated dialysis fluid piping, which is a weakness of the central dialysis fluid delivery system, and provide ultrapure dialysis fluid for a long term. Combination of heat water disinfection, continuous water circulation, and minimalized dead space in the dialysis piping were designed for a central dialysis fluid delivery system and used in a clinic for 6 years. As an index of water purification, endotoxin concentrations and microbial colony counts in reverse osmosis water and dialysis fluid were measured. In addition, we performed scanning electron microscopy of the silicon tube surface that had been used for 5 years to confirm the presence or absence of biofilm formation. For 6 years, endotoxin concentrations and microbial colonies were not detected in reverse osmosis water and dialysis fluid using the multiple-patient dialysis fluid supply equipment. The purity of the dialysis fluid was maintained. No biofilm formation was observed by scanning electron microscopy. Combination of heat water disinfection, continuous water circulation, and minimalized dead space designs for dialysis piping can supply ultrapure dialysis fluid with minimal biofilm formation in the piping in the long term.

Particulates formed in dialysis fluid: effect of silica in tap water

Background

A fluid commonly used for dialysis in Japan is prepared from two dialysate concentrates and dialysis water. Silicon (Si) from tap water is reported in dialysis water as suspended insoluble particulate matters. We aimed to examine the source of insoluble particulate matters in the online prepared substitution fluid and to examine effects of the silica (SiO2) of tap water on the SiO2 of dialysis water.

Method

Based on the number of particles and particle size distribution in online prepared substitution fluid, we evaluated particle diameters and constituent elements of particles in online prepared substitution fluid. To identify sources of insoluble particulate matters in the online prepared substitution fluid, we measured particle diameters and constituent elements of particles adhering to the surface of hollow fiber of the final endotoxin-retentive filter (ETRF) and to the inner surface of the housing of the final ETRF and measured SiO2 in tap water, dialysis water, and commercial sterile substitution fluid.

Results

Si-containing particles accounted for 83% of 30 particles detected in the final ETRF (the hollow fibers and the housing) and the online prepared substitution fluid sampled from the final ETRF. The large variability in the SiO2 in tap water depending on the geographic regions. The SiO2 in dialysis water was 0.4–0.7 mg/L. Si was not detected in particles in the commercial sterilized substitution fluid, and the commercial sterile substitution fluids contained SiO2 at 0.1 mg/L.

Conclusion

We presume that insoluble particulates in online prepared substitution fluid were calcium and magnesium precipitated from dialysate and Si precipitated from dialysis water. Moreover, variation in the SiO2 in tap water is a factor affecting the SiO2 level in dialysis water. If the formation of silicates in the online prepared substitution fluid is considered and the target SiO2 in dialysis water is to be set ≤ 0.1 mg/L, SiO2 in tap water available in hospitals and dialysis centers should be known before specifications of instruments for dialysis fluid preparation are determined.

Particulates formed in online prepared substitution fluid- Effect of acetic acid cleaning on endotoxin retentive filters

INTRODUCTION

There is no standard for insoluble particulate matters in dialysate. We evaluated the insoluble particulate matters in online prepared substitution fluid.

METHODS

We evaluated particle diameters and constituent elements of particles in online prepared substitution fluid and the final endotoxin retentive filter (ETRF).

RESULTS

The measurement results with particles in the online prepared substitution fluid and particles attached to the final ETRF revealed that Ca-containing particles accounted for 11 particles and Si-containing particles accounted for 19 particles of 30 particles detected in the online prepared substitution fluid and the final ETRF.

CONCLUSION

We presume that insoluble particulates in online prepared substitution fluid were Ca and Mg precipitated from dialysate and Si precipitated from dialysis water. Even if two ETRFs were connected in series, these particles were formed in the final ETRF.

Choices in hemodialysis therapies: variants, personalized therapy and application of evidence-based medicine

The extent of removal of the uremic toxins in hemodialysis (HD) therapies depends primarily on the dialysis membrane characteristics and the solute transport mechanisms involved. While designation of ‘flux’ of membranes as well toxicity of compounds that need to be targeted for removal remain unresolved issues, the relative role, efficiency and utilization of solute removal principles to optimize HD treatment are better delineated. Through the combination and intensity of diffusive and convective removal forces, levels of concentrations of a broad spectrum of uremic toxins can be lowered significantly and successfully. Extended clinical experience as well as data from several clinical trials attest to the benefits of convection-based HD treatment modalities. However, the mode of delivery of HD can further enhance the effectiveness of therapies. Other than treatment time, frequency and location that offer clinical benefits and increase patient well-being, treatment- and patient-specific criteria may be tailored for the therapy delivered: electrolytic composition, dialysate buffer and concentration and choice of anticoagulating agent are crucial for dialysis tolerance and efficacy. Evidence-based medicine (EBM) relies on three tenets, i.e. clinical expertise (i.e. doctor), patient-centered values (i.e. patient) and relevant scientific evidence (i.e. science), that have deviated from their initial aim and summarized to scientific evidence, leading to tyranny of randomized controlled trials. One must recognize that practice patterns as shown by Dialysis Outcomes and Practice Patterns Study and personalization of HD care are the main driving force for improving outcomes. Based on a combination of the three pillars of EBM, and particularly on bedside patient–clinician interaction, we summarize what we have learned over the last 6 decades in terms of best practices to improve outcomes in HD patients. Management of initiation of dialysis, vascular access, preservation of kidney function, selection of biocompatible dialysers and use of dialysis fluids of high microbiological purity to restrict inflammation are just some of the approaches where clinical experience is vital in the absence of definitive scientific evidence. Further, HD adequacy needs to be considered as a broad and multitarget approach covering not just the dose of dialysis provided, but meeting individual patient needs (e.g. fluid volume, acid–base, blood pressure, bone disease metabolism control) through regular assessment—and adjustment—of a series of indicators of treatment efficiency. Finally, in whichever way new technologies (i.e. artificial intelligence, connected health) are embraced in the future to improve the delivery of dialysis, the human dimension of the patient–doctor interaction is irreplaceable. Kidney medicine should remain ‘an art’ and will never be just ‘a science’.

Occurrence and fate of endotoxin activity at drinking water purification plants and healthcare facilities in Japan

Occurrence of residual endotoxin activity (ET) in dialysis water and also tap water as its source is a matter of great concern to medical professionals conducting dialysis therapy at healthcare facilities (HCFs). The present study was performed to determine the occurrence and fate of the ET at selected Japanese drinking water purification plants and HCFs between 2014 and 2016. Chemical coagulation and sedimentation, rapid sand filtration, and membrane filtration were highly effective to decrease both ET dissolved in water (free-ET) and ET bound to cells/particles (bound-ET). Moderate decreases in bound-ET and limited decreases in free-ET were observed by chlorination and ozonation. Bacterial activated carbon filtration was a major cause of significant increases in endotoxin activity during the course of drinking water purification process. Levels of residual ET in water supplied to HCFs were strongly affected by their source waters and the configurations of water purification processes served. Microbial regrowth on the premises, from water tanks to faucets at HCFs could also contribute to ET increases in tap water.

Utility of Ultrasonography of the Median Nerve With a High-Frequency Probe for the Diagnosis of Dialysis-Related Carpal Tunnel Syndrome

This cross-sectional study aimed to determine the utility of ultrasonography with improved resolution using a high-frequency probe for dialysis-related carpal tunnel syndrome (CTS). This study targeted 125 hemodialysis patients at our hospital. A 12 MHz probe was placed on the carpal tunnel area to identify the median nerve. The compression rate of the nerve was calculated by measuring the smallest diameter of the compressed nerve and largest diameter of the unaffected part. To quantify CTS symptoms, we determined the presence of Tinel's sign, measured pinch strength, and used questionnaires to assess numbness and pain. The association of these clinical data with the compression rate was examined. Mean compression rate was 12.1 ± 1.1%. The compression rate cutoff value for those positive with Tinel's sign was 25%, (sensitivity and specificity were 0.80 and 0.91, respectively), and that for those with a history of CTS surgery was 25% (sensitivity and specificity were 0.67 and 0.89, respectively). Multiple regression analysis identified duration of dialysis, β2-microglobulin(β2-Mg) concentration, positivity for Tinel's sign, history of CTS surgery, and pinch strength as independent compression rate determinants. Notably, compression rates were significantly higher in patients with a ≥4-year duration of dialysis and a β2-Mg level of 20 mg/L or more. The compression rate of the median nerve measured by an improved ultrasound device significantly correlated with clinical symptoms, medical history, and serological features associated with dialysis-related CTS. Because ultrasonography is non-invasive, the examination might be a simple method especially for early diagnosis of dialysis-related CTS.

Japanese society for dialysis therapy renal data registry-a window through which we can view the details of Japanese dialysis population

The Japanese Society for Dialysis Therapy (JSDT) collects the clinical data from all the facilities to create a nation-wide registry system named JSDT Renal Data Registry (JRDR). This survey was begun in 1966 as a form of facility survey. Patient survey started in 1983. More than 95% of facilities respond to the survey on the basis of voluntary work of facility staffs. Therefore, JRDR has the longest history and the most comprehensive coverage. As for the prevalent patients, 304,856 patients are treated by dialysis therapy in Japan as of the year 2011. The demographics of the Japanese dialysis population have been markedly changing in terms of age, primary diagnoses and dialysis vintage. The mean age of prevalent population reaches 66.55 years at the end of 2011. The increase in the numbers of dialysis population is due to the growth of those older than 65 years old. Patients with the vintage longer than 20 years account for 8% of the entire population. Around 38 thousands patients started their dialysis treatments, whereas 31 thousands deceased. The disease burden of cardiovascular diseases as well as infection is substantial due to the demographic changes. Many evidences have been reported from the data obtained from JRDR to date. These findings covers a wide range of dialysis practice and are utilized for the development of JSDT guidelines. Therefore, JRDR has provided indispensable and fundamental data of Japanese dialysis population.