KDOQI Clinical Practice Guideline for vascular access: 2019 update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidencebased guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research

Thermal disinfection in hemodialysis using the A0 concept as dispenser. / Desinfección térmica en hemodiálisis usando el concepto A0 como dosificador.

Patients with chronic kidney disease in the hemodialysis program are exposed to large amounts of water, as this constitutes about 96% of the dialysis fluid. It is known that the use of better quality water decreases the state of chronic inflammation in dialysis patients. Disinfection as part of water treatment plays an important role in meeting the established quality standards; currently, heat disinfection is highly recommended, however its dose is not clearly established in the literature. The objective of this review is to know what is available in the literature on the dose of heat disinfection that should be used in hemodialysis and to present our experience with this method at a set dose of 12.000 A0.

Saúde incorpora procedimento de hemodiálise para pacientes em trânsito

Medida é uma antiga demanda dos estados e municípios e é voltada para pacientes que precisam de hemodiálise fora da cidade em que normalmente fazem o tratamento

[The role of pharmacist in a telemedicine collaboration in hemodialysis: Water bacteriological quality monitoring]. / Rôle du pharmacien dans un partenariat de télémédecine en hémodialyse : la surveillance microbiologique de l'eau.

OBJECTIVES: In French health centers, the pharmacist is responsible for the quality of hemodialysis fluids. In an insular hospital, it is difficult to make bacteriological controls because of the lack of an environmental laboratory. Alternative choices of methods must be seek to facilitate water control and ensure the security of hemodialysis for patients. Controlling the microbiological risk is an essential condition for the good operation of a telemedicine partnership in dialysis. METHODS: A review of the different methods that has been tried is presented. The hospital has experienced since 2014 a microorganism detection test by ATPmetry. An overview of the results is discussed. RESULTS: The usability of this technique allows quarterly controls on the water treated by reverse osmosis and on fluids after one and two ultrafiltrations from every generator. Cases of non-compliance were due to false positives, which were squashed by verification control in 50% of the cases, and the other non-compliances were fixed by corrective actions. CONCLUSIONS: The ATPmetry technique permits the collection of rapid results and verification of the effectiveness of the corrective actions immediately after their implementation. This method has been undertaken in a routine use instead of the reference technique (bacteriological cultures). Assuming a constant vigilance in the quality of dialysis fluids that is a part of a quality approach, the pharmacist is at the heart of the telemedicine partnership developed in hemodialysis on the island.

Estudio de la eficacia de sellado en el periodo interdialítico largo para catéteres de hemodiálisis disfuncionantes / Study of sealing efficiency in the long interdialytic period for dysfunctioning hemodialysis catheters

El sellado de los catéteres venosos tunelizados con distintas soluciones se ha utilizado tanto en la prevención como en el tratamiento de complicaciones, sin embargo, no existe la solución ideal. El objetivo del estudio es comparar las complicaciones de de los catéteres disfuncionantes con diferentes pautas de sellado de fin de semana, Urokinasa 10.000 UI vs TauroLock(TM)-U25.000, así como eficacia dialítica de los mismos. Se trata de un estudio observacional longitudinal de cohorte en el que se analizan los casos de infección, trombosis y funcionalidad del catéter tunelizado. Se incluyen sólo los pacientes con catéter disfuncionante que tenían previamente prescrita una pauta de sellado con urokinasa en el periodo interdialítico largo. El periodo de estudio fue de cuatro meses; dos con sellado con 10.000 UI de Urokinasa y dos con sellado de TauroLock(TM)-U25.000. Las medias de Urokinasa vs Taurolidina: flujo sanguíneo, PV, recirculación, KT (53.3/55L), manipulación y dosis extra de urokinasa fueron mejor en el periodo de Taurolock, aunque no se encontraron diferencias estadísticamente significativas. La media de PA es cercana a la significación (p=0.067) mejor también en el periodo de Taurolock. Hubo una diferencia en la media de KT favorable al periodo de Taurolock que no tiene significación estadística y es exclusivo de los pacientes que no necesitaron urokinasa extra. La principal limitación de nuestro estudio es el tamaño muestral que puede ser el responsable en parte, de la ausencia de significación estadística. Son necesarios estudios con mayor número de pacientes (AU)

The sealing of the tunneled venous catheters with different solutions has been used both in prevention and in the treatment of complications, however, there is no ideal solution. The aim of the study is to compare the complications of dysfunctional catheters with different weekend sealing patterns, Urokinase 10,000 IU vs TauroLock(TM) -U25,000, as well as dialytic efficacy of both substances. A longitudinal observational cohort study in which the cases of infection, thrombosis and functionality of the tunneled catheter were analyzed. Only patients with a dysfunctioning catheter who had previously prescribed a sealing pattern with urokinase in the long interdialytic period were included. The study period was four months; two months sealed with 10,000 IU of Urokinase and the other ones, sealed with TauroLock (TM) -U25,000. Urokinase vs Taurolidine averages: blood flow, venous pressure, recirculation, KT (53.3 / 55L), manipulation and extra doses of urokinase were better in the Taurolock period, although no statistically significant differences were found. The mean arterial pressure is close to the significance (p = 0.067), also better in the Taurolock period. There was a difference in the KT mean, favorable to the Taurolock period, which has no statistical significance and is exclusive to patients who did not require extra urokinase. The main limitation of our study is the sample size that may be partly responsible for the absence of statistical significance. Studies with more patients are necessary (AU)

Japan's Support of Hemodialysis in Southeast Asia.

BACKGROUND: With continuing economic development in the developing countries of Southeast Asia, the numbers of dialysis facilities and patients are increasing every year. However, dialysis-related devices tend to be provided with financial support from developed countries and/or donations from nonprofit organizations, and some donated devices are disposed of, without attempts at repair, when they break down. Device management and dialysate quality can also be problematic. SUMMARY: To help address these issues, Japan started to provide technical guidance and support for dialysate purification in these countries. As a result, dialysate quality improved and local medical staff can now perform dialysis therapy using purified dialysate. At the same time, education was provided to staff, and their improved knowledge and skills have contributed to appropriate device maintenance, ensuring the dialysate used is of sufficient quality. Currently, approaches for human resource development are being actively provided in these countries through cooperation with local academic societies or other organizations in the field. Key Messages: A review of the current status of management of dialysis-related devices and dialysate quality in developing countries reveals that financial support and donations for medical devices alone are insufficient and the development of local human resources is crucial. Nurturing and training of clinical engineers, who directly operate today's advanced medical devices for patients, as well as device maintenance and management are urgent issues to address.

Preparation and Quality Management of Fluids for Hemodialysis.

BACKGROUND: In 2008, the Japanese Society for Dialysis Therapy (JSDT) proposed a standard for the quality of fluids for hemodialysis. The standard was geared toward Japan, where the central dialysis fluid delivery system is routinely used. After establishment of the standard, dialysis fluid quality was markedly improved in facilities across the country. Moreover, the number of on-line hemodiafiltration patients dramatically increased. SUMMARY: However, the 2008 standard specifies only microbiological qualities and does not cover toxic chemicals. The basis of toxic chemical management depends on the source water and water treatment equipment for hemodialysis, but no standard applies to water treatment equipment as a medical device. Specifications for the equipment were, for the most part, entrusted to individual manufacturers. Key Messages: The JSDT is investigating revision of its standard for dialysis fluid quality for hemodialysis to add control standards for toxic chemicals and water treatment equipment, with the aim of achieving quality of dialysis water superior to that of terminal dialysis fluid.

Guideline for dialysate quality of Spanish Society of Nephrology (second edition, 2015). / Guía de gestión de calidad del líquido de diálisis (LD) (segunda edición, 2015).

A Best Practice Guideline about Dialysis fluid purity was developed under the leadership of the Spanish Society of Nephrology in 2004. The second edition revised Guideline considered new evidences and International Standard. The Guideline has established recommendations for standards for preparing dialysate: water, concentrates and hemodialysis proportioning systems. This Guideline is based on the ISO13959, European Pharmacopoeia, the Real Farmacopea Española, the AAMI Standards and Recommended Practices, European Best Practice Guidelines for Haemodialysis, literature reviews, according to their level of evidence, and the opinion of the expert Spanish group. Two levels of quality of water were defined: purified water and high purified water (ultra pure) and for dialysate: ultra pure dialysate. Regular use of ultra pure dialysate is recommended for all type of hemodialysis to prevent and delay the occurrence of complications: inflammation, malnutrition, anaemia and amiloidosis. Water, concentrates and dialysate quality requirements are defined as maximum allowable contaminant levels: chemicals (4.1.2), conductivity, microbial and endotoxins (4.1.1): Monitoring frequency, maintenance and corrective actions were specified. Methods of sampling and analysis were described in appendix (anexos). For microbiological monitoring, R2A medium is recommended, incubated during 7-14 days at a temperature of 17-23°C. The dialysate quality assurance process involves all dialysis staff members and requires strict protocols. The physician in charge of hemodialysis has the ultimate responsibility for dialysate quality. All suggestions and questions about this Guideline are wellcome to www.senefro.org.

The choice of dialysate bicarbonate: do different concentrations make a difference?

Metabolic acidosis is a common complication of chronic kidney disease; it is typically caused by the accumulation of sulfate, phosphorus, and organic anions. Metabolic acidosis is correlated with several adverse outcomes, such as morbidity, hospitalization, and mortality. Thus, correction of metabolic acidosis is fundamental for the adequate management of many systemic complications of chronic kidney disease. In patients undergoing hemodialysis, acid-base homeostasis depends on many factors including the following: net acid production, amount of alkali given by the dialysate bath, duration of the interdialytic period, and residual diuresis, if any. Recent literature data suggest that the development of metabolic alkalosis after dialysis may contribute to adverse clinical outcomes. Our review is focused on the potential effects of different dialysate bicarbonate concentrations on hard outcomes such as mortality. Unfortunately, no randomized studies exist about this issue. Acid-base equilibrium is a complex and vital system whose regulation is impaired in chronic kidney disease. We await further studies to assess the extent to which acid-base status is a major determinant of overall survival in patients undergoing hemodialysis. For the present, the clinician should understand that target values for predialysis serum bicarbonate concentration have been established primarily based on observational studies and expert opinion. Based on this, we should keep the predialysis serum bicarbonate level at least at 22 mmol/l. Furthermore, a specific focus should be addressed by the attending nephrologist to the clinical and nutritional status of the major outliers on both the acid and alkaline sides of the curve.

Dialysis fluid endotoxin level and mortality in maintenance hemodialysis: a nationwide cohort study.

BACKGROUND: The quality of dialysis fluid water might play an important role in hemodialysis patient outcomes. Although targeted endotoxin levels of dialysis fluid vary among countries, evidence of the contribution of these levels to mortality in hemodialysis patients is lacking. STUDY DESIGN: Retrospective cohort study using data from the Japan Renal Data Registry, a nationwide annual survey. SETTING & PARTICIPANTS: 130,781 patients receiving thrice-weekly in-center hemodialysis for more than 6 months were enrolled at 2,746 facilities in Japan at the end of 2006. None of the patients changed facility or treatment modality during 2007. PREDICTOR: Highest endotoxin level in dialysis fluid reported by each facility during 2006. Patients were categorized by facility endotoxin level into the following groups: <0.001, 0.001 to <0.01, 0.01 to <0.05, 0.05 to <0.1, and ≥0.1EU/mL. Age, sex, dialysis vintage, diabetes mellitus as a primary cause of end-stage renal disease, Kt/V, normalized protein catabolic rate, dialysis session duration, serum albumin, and hemoglobin were measured as potential confounders. OUTCOME: All-cause mortality, censored by transplantation; withdrawal from dialysis treatment; or end of follow-up. RESULTS: Of 130,781 hemodialysis patients, 91.2% had facility endotoxin levels below the limit set for dialysis fluid in Japan (<0.05EU/mL). During a 1-year follow-up, 8,978 (6.9%) patients died of all causes. The rate of all-cause mortality at 1 year was highest in the ≥0.1-EU/mL category (88.0 deaths/1,000 person-years). Patients in the ≥0.1-EU/mL group exhibited an increased risk of all-cause mortality of 28% (95% CI, 10%-48%) compared to the <0.001-EU/mL group. LIMITATIONS: Endotoxin level in dialysis fluid is reported as categorical data. No information about variation in endotoxin levels in dialysis fluid over time. CONCLUSIONS: Higher facility endotoxin levels in dialysis fluid may be related to increased risk for all-cause mortality among hemodialysis patients. Correcting this modifiable facility water management practice might improve the outcome of hemodialysis patients.

Experience in using thermal disinfection to remove viable bacteria and endotoxins in centraly distributed reverse osmosis water.

INTRODUCTION: The water used for dilution of hemodialysis concentrates has to meet official quality recommendations regarding microbiology and chemical parameters. To avoid chemical use and to simplify treatments, hot water has been used to control microbial contamination of water distribution systems. In this study we evaluated the efficacy of heat disinfection in maintaining the quality of dialysis water generated by reverse osmosis (RO). METHODS: During the first part of the study, we consecutively used (1) continuous water circulation, (2) daily heat disinfection and (3) a combination of daily heat disinfection and weekly chemical disinfection while checking bacterial count and endotoxin level every 4-5 weeks. During the second part of the study, we continued using daily heat disinfection while checking bacterial count and endotoxin level on weekly basis. RESULTS: The endotoxin levels at all sampling points of the water treatment system were lower than 0.005/ ml throughout the study. The application of heat disinfection alone reduced bacterial levels but an escape phenomenon occurred. After an interval of 21 days, an exponential increase of bacterial count was noted and cultures from the RO unit revealed growth of Pseudomonas fluorescence. The addition of chemical disinfection was successful in eliminating micro-organisms. Throughout this study, micro-organisms and endotoxins were not detectable in dialysate fluid and substitution fluid in dialysis monitors. CONCLUSION: The isolation of a thermo-sensitive organism from the RO unit after a period of relying on thermal disinfection suggests the existence of dead space in the RO unit that is not adequately exposed to heat but is accessible to chemical disinfection. .

Standardising dialysate potassium does not increase patient risk.

BACKGROUND: Rapid intradialytic potassium shifts during haemodialysis have been associated with increased mortality and morbidity. Standardising dialysate potassium to 2 mmol/l may decrease the potassium shift. OBJECTIVE: To examine the effect of standardising dialysate potassium to 2 mmol/l for all chronic dialysis treatments. DESIGN: Pre- and post-intervention comparison of monthly serum potassium. PARTICIPANTS: Ninety-seven individuals, of whom 56 patients could be matched across both data collection periods. METHODS: Serum potassium data were categorised based on a target range 3.5-6.0 mmol/l. Overall pre- and post-intervention mean scores were compared using a paired samples t-test. Data for patients routinely prescribed dialysate potassium 1 mmol/l pre-intervention (n = 6) underwent paired samples t-test to compare their mean serum potassium pre- and post-intervention. RESULTS: There was no statistically significant change in serum potassium post-intervention. The majority of patients remained within the target range, including the subset of patients who had a history of high serum potassium during the pre-intervention period. CONCLUSIONS: A standard potassium dialysate of 2 mmol/l may reduce intradialytic serum potassium shifts and may assist in standardising safer work practices.

Hemodialysis and water quality.

Over 383,900 individuals in the U.S. undergo maintenance hemodialysis that exposes them to water, primarily in the form of dialysate. The quality of water and associated dialysis solutions have been implicated in adverse patient outcomes and is therefore critical. The Association for the Advancement of Medical Instrumentation has published both standards and recommended practices that address both water and the dialyzing solutions. Some of these recommendations have been adopted into Federal Regulations by the Centers for Medicare and Medicaid Services as part of the Conditions for Coverage, which includes limits on specific contaminants within water used for dialysis, dialysate, and substitution fluids. Chemical, bacterial, and endotoxin contaminants are health threats to dialysis patients, as shown by the continued episodic nature of outbreaks since the 1960s causing at least 592 cases and 16 deaths in the U.S. The importance of the dialysis water distribution system, current standards and recommendations, acceptable monitoring methods, a review of chemical, bacterial, and endotoxin outbreaks, and infection control programs are discussed.

Estudio piloto comparativo de dos soluciones de sellado en catéteres de hemodiálisis: heparina sódica al 5 por ciento frente a fibrilin® / Comparative pilot study of two haemodialysis catheter lock solutions: 5 percent heparin sodium compared to fibrilin®

El sellado de catéteres en hemodiálisis suele ser motivo de controversia entre los distintos profesionales dedicados a la hemodiálisis. El objetivo del presente estudio es comparar dos soluciones de sellado de catéter para hemodiálisis: heparina al 5% y fibrilin (heparina 20ui/ml + metil y propilparaben). Estudiamos 8 pacientes (mujeres) de 69±12 años portadoras de catéter tunelizado de 17±7 meses de duración del catéter, estables y que habían dado su consentimiento para el estudio. Inicialmente se selló con fibrilin durante un mes (12 sesiones) y posteriormente con heparina al 5% el mismo periodo de tiempo. Se registró velocidad de bomba, flujo efectivo, presión venosa, KT, necesidad de utilizar fibrinolíticos, infecciones, nº de manipulaciones, hipotensiones, recirculación, KT/V, TP, TPTA. Se compararon los estudios mediante t student. Después de dos meses de estudio se observó mayor flujo efectivo 318±23 ml/m en catéteres sellados con heparina frente a 307±17 ml/m con fibrilin (p= 0,008), menor presión venosa 147±12 mm Hg en heparina frente a 168±17 en fibrilin (p=0,006), mayor KT en heparina 43±3 litros frente a 41±4 litros en fibrilin. A pesar de estas mejores condiciones, clínicamente no supusieron diferencias en la eficacia dialítica KT/V heparina 1,56±0,2 frente a 1,59 ±0,2 en fibrilin. Si se observó un mayor nº de manipulaciones del catéter en heparina 12±0,2 frente a 9,4±1,3 en fibrilin (p=0,001). No existieron diferencias en aparición de infecciones, recirculación, necesidad de fi brinoliticos o alteraciones de coagulación. Concluimos que el sellado de catéteres de Hemodiálisis con Fibrilin es una alternativa eficaz a la heparina al 5%. No se acompaña de un mayor grado de disfunción del catéter y si de un menor nº de manipulaciones, lo que podría condicionar un menor nº de infecciones asociado a catéteres(AU)

Catheter locks in haemodialysis are usually a source of controversy among the different professionals involved in haemodialysis. The aim of this study is to compare two haemodialysis catheter lock solutions: 5% heparin and fibrilin (heparin 20ui/ml + methyl and propyl paraben). We studied 8 patients (women) aged 69±12 years with tunnelled catheters of 17±7 months’ duration, whose condition was stable and who had given their consent to the study. Initially, the fibrilin lock solution was used with the catheters for one month (12 sessions) and then 5% heparin for the same length of time. Pump speed, effective flow, venous pressure, KT, the need to use fibrinolytics, infections, number of handlings, hypotension episodes, recirculation, KT/V, TP, TPTA were measured. The results were compared using student’s t-test. After two months of study, a greater effective flow 318±23 ml/m was observed in catheters with heparin lock compared to 307±17 ml/m with fibrilin (p= 0.008), lower venous pressure 147±12 mm Hg in heparin compared to 168±17 in fibrilin (p=0,006), higher KT in heparin 43±3 litres compared to 41±4 litres in fibrilin. Despite these better conditions, they did not represent clinical differences in dialysis efficacy, KT/V heparin 1.56±0.2 compared to 1.59 ±0.2 in fibrilin. A higher number of catheter handlings was observed in heparin 12±0.2 compared to 9.4±1.3 in fibrilin (p=0.001). There were no differences in the appearance of infections, recirculation, need for fi brinolytics or coagulation alterations. We conclude that the use of fibrilin lock solution for haemodialysis catheters is an effective alternative to 5% heparin. It is not accompanied by a higher degree of catheter dysfunction but does involve less handling, which could lead to fewer catheter-associated infections(AU)

The impact of membrane permeability and dialysate purity on cardiovascular outcomes.

The effects of high-flux dialysis and ultrapure dialysate on survival of hemodialysis patients are incompletely understood. We conducted a randomized controlled trial to investigate the effects of both membrane permeability and dialysate purity on cardiovascular outcomes. We randomly assigned 704 patients on three times per week hemodialysis to either high- or low-flux dialyzers and either ultrapure or standard dialysate using a two-by-two factorial design. The primary outcome was a composite of fatal and nonfatal cardiovascular events during a minimum 3 years follow-up. We did not detect statistically significant differences in the primary outcome between high- and low-flux (HR=0.73, 95% CI=0.49 to 1.08, P=0.12) and between ultrapure and standard dialysate (HR=0.90, 95% CI=0.61 to 1.32, P=0.60). Posthoc analyses suggested that cardiovascular event-free survival was significantly better in the high-flux group compared with the low-flux group for the subgroup with arteriovenous fistulas, which constituted 82% of the study population (adjusted HR=0.61, 95% CI=0.38 to 0.97, P=0.03). Furthermore, high-flux dialysis associated with a lower risk for cardiovascular events among diabetic subjects (adjusted HR=0.49, 95% CI=0.25 to 0.94, P=0.03), and ultrapure dialysate associated with a lower risk for cardiovascular events among subjects with more than 3 years of dialysis (adjusted HR=0.55, 95% CI=0.31 to 0.97, P=0.04). In conclusion, this trial did not detect a difference in cardiovascular event-free survival between flux and dialysate groups. Posthoc analyses suggest that high-flux hemodialysis may benefit patients with an arteriovenous fistula and patients with diabetes and that ultrapure dialysate may benefit patients with longer dialysis vintage.

Dialysate calcium concentration and mineral metabolism in long and long-frequent hemodialysis: a systematic review and meta-analysis for a Canadian Society of Nephrology clinical practice guideline.

BACKGROUND: Patients treated with conventional hemodialysis (HD) develop disorders of mineral metabolism that are associated with increased morbidity and mortality. More frequent and longer HD has been associated with improvement in hyperphosphatemia that may improve outcomes. STUDY DESIGN: Systematic review and meta-analysis to inform the clinical practice guideline on intensive dialysis for the Canadian Society of Nephrology. SETTING & POPULATION: Adult patients receiving outpatient long (≥5.5 hours/session; 3-4 times per week) or long-frequent (≥5.5 hours/session, ≥5 sessions per week) HD. SELECTION CRITERIA FOR STUDIES: We included clinical trials, cohort studies, case series, case reports, and systematic reviews. INTERVENTIONS: Dialysate calcium concentration ≥1.5 mmol/L and/or phosphate additive. OUTCOMES: Fragility fracture, peripheral arterial and coronary artery disease, calcific uremic arteriolopathy, mortality, intradialytic hypotension, parathyroidectomy, extraosseous calcification, markers of mineral metabolism, diet liberalization, phosphate-binder use, and muscle mass. RESULTS: 21 studies were identified: 2 randomized controlled trials, 2 reanalyses of data from the randomized controlled trials, and 17 observational studies. Dialysate calcium concentration ≥1.5 mmol/L for patients treated with long and long-frequent HD prevents an increase in parathyroid hormone levels and a decline in bone mineral density without causing harm. Both long and long-frequent HD were associated with a reduction in serum phosphate level of 0.42-0.45 mmol/L and a reduction in phosphate-binder use. There was no direct evidence to support the use of a dialysate phosphate additive. LIMITATIONS: Almost all the available information is related to changes in laboratory values and surrogate outcomes. CONCLUSIONS: Dialysate calcium concentration ≥1.5 mmol/L for most patients treated with long and long-frequent dialysis prevents an increase in parathyroid hormone levels and decline in bone mineral density without increased risk of calcification. It seems prudent to add phosphate to the dialysate for patients with a low predialysis phosphate level or very low postdialysis phosphate level until more evidence becomes available.

Purity and stability of online-prepared hemodiafiltration fluid after storage.

BACKGROUND/AIMS: Previous studies have suggested that online hemodiafiltration (OL-HDF) fluid can be used as dialysate for continuous renal replacement therapies, and thus HDF costs can be reduced. The aims of this study were to determine the purity of OL-HDF fluid and to verify the stability of the electrolyte composition and acid-base balance during its storage. METHODS: OL-HDF fluid was collected in 70 individual bags and stored for up to 7 days. The following tests were performed daily in 10 bags: natural visible precipitation (macrocrystallization), sample collection for chemical analysis and fluid culture, limulus amebocyte lysate endotoxin test, standard culture of NALGENE® filters after passing of the fluid, and molecular analysis of bacterial DNA. RESULTS: The values of pH and pCO(2) showed a significant change starting at 24 h (p < 0.001); after 72 h, their values were beyond the measurable range. Coefficient of variation for pCO(2) was as high as 25.7%. Electrolyte composition (Na(+), K(+), Cl(-), Ca(2+) and glucose) showed a statistically significant difference over time (p < 0.05); however, their coefficients of variation were low (1.7, 1.4, 0.6, 2.3 and 0.9%, respectively), which might not be considered clinically significant. Negative results were obtained at all points by fluid and filter cultures, endotoxin test and molecular analysis. No macrocrystallization was observed at any time point. CONCLUSIONS: We demonstrate the microbiological purity of OL-HDF fluid stored for up to 7 days. The electrolyte composition was stable, except for a relevant change in pCO(2) and consequently in pH (first noted at 24 h), emphasizing the need to reassess the acid-base balance in multilayer plastic bags in future studies.

Pre-emptive replacement of water treatment components improves responsiveness to erythropoiesis-stimulating agents in maintenance haemodialysis patients: a quality improvement report.

Hypo-responsiveness to erythropoiesis-stimulating agents (ESAs) has been associated with increased mortality. We examined the effect of water treatment component replacement on declining ESA responsiveness in the absence of chemical or microbiological standards failure. Pre-emptive renewal of the water treatment system supplying 802 standard-flux haemodialysis patients resulted in a significant rise in haemoglobin from (mean ± SD) 12.1 ± 1.2 to 12.3 ± 1.0 g/dl (p < 0.0001), accompanied by a significant decrease in prescribed dose of darbepoetin alfa from 47.9 ± 27.3 to 44.7 ± 27.6 µg/week (p < 0.0001). ESA responsiveness improved significantly from 0.060 ± 0.041 to 0.055 ± 0.040 µg/kg/g · dl(-1) (p < 0.0001) and the number of patients no longer requiring ESA therapy increased threefold. These benefits were derived in the absence of haemolysis or significant changes in water quality. Renewal of water system components should be conducted even in the absence of proven microbiological and chemical failure.

The evolution of technological strategies in the prevention of dialysis water pollution: sixteen years' experience.

AIM: This report attempts to illustrate the positive impact on the quality of dialysis water produced over a 16-year period through the progressive optimization of technological procedures. METHODS: Fundamental steps included the following: elimination of polyvinyl chloride (PVC), periodical controls, introduction of stainless steel and/or polyethylene polymer and substitution of single-pass reverse osmosis (SRO) with double-pass reverse osmosis (DRO). Daily overnight automatic thermal disinfection of distribution piping rings represented the final step. RESULTS: A dramatic improvement was observed in 645 water samples obtained from distribution piping. The measures applied resulted in a significant improvement of water quality, featuring levels of colony-forming units per milliliter ranging from 247.4 ± 393.7 in the presence of PVC and SRO to 14.1 ± 28.0 with stainless steel and DRO and 2.8 ± 3.2 with cross-linked polyethylene thermoplastic polymer and DRO (p < 0.01). CONCLUSIONS: Dialysis water should be viewed by nephrologists as a medicinal product, and every effort should be made to ensure a high-quality liquid.