Is Expanded Hemodialysis an Option to Online Hemodiafiltration for Small- and Middle-Sized Molecules Clearance?

BACKGROUND: Recent evidence suggests a better reduction rate of some uremic toxins with expanded hemodialysis (HDx). METHODS: Prospective study including 8 hemodialysis patients. We divided the study in 2 phases; within the first one, we assigned 4 patients (group 1) to undergo online hemodiafiltration with a PF 210H dialyzer, and the other 4 patients (group 2) to undergo HDx with the high retention onset Theranova 500 dialyzer during 24 sessions. Later, during the second phase and after a washout period, the same patients were switched to receive HDx (group 1) and HDF (group 2). RESULTS: No differences were found in the Urea and ß2-microglobulin reduction ratio. However, in the case of myoglobin, the reduction ratio with HDF was 35 vs. 60% with HDx (p < 0.001). Similarly, in the case of prolactin, the reduction ratio with HDF was 45 and 61% with HDx (p < 0.001). CONCLUSIONS: We conclude that HDx is not inferior to online hemodiafiltration in the clearance of small and middle molecules and could be superior in the clearance of larger middle molecules.

Expanded home hemodialysis: case reports.

Among the different hemodialysis (HD) strategies, the short daily hemodialysis performed at home (SDHHD) provides clinical benefits to the patient. Expanded hemodialysis (HDx) employs cutoff medium membranes that exhibit greater clearance capacity of uremic toxins of medium-high molecular weight. This case series study reported the results of seven patients who were transferred to expanded hemodialysis at home (HHDx), from December 2017 to March 2019, over a 12-month follow-up period. The AK-98 monitor and Theranova 400 membrane (Baxter International Inc., Deerfield, IL, USA) were used. The main outcome measures were blood analytical values and drug consumption. The blood levels of ß2-microglobulin were significantly reduced (p = 0.0082), while maintaining albumin levels with less use of phosphorus binders. Regarding the safety profile, technique-related adverse events were not reported. According to the results of the current study, HHDx was a safe technique, which additionally had the ability to provide benefits to patients due to its greater purification capacity. Further studies, especially multicenter ones, with a greater number of patients are needed to confirm these results.

Advanced Chronic Kidney Disease Units in Spain: a national survey on standards of structure, resources, results and patient safety. / Unidades de Enfermedad Renal Crónica Avanzada en España: una encuesta nacional sobre los estándares de estructura, recursos, resultados y seguridad del paciente.

BACKGROUND AND OBJECTIVE: Recently, the Advanced Chronic Kidney Disease Units (UERCA, in Spanish) have been developed in Spain to offer a better quality of life to patients with advanced chronic kidney disease (ACKD), improving their survival and reducing morbidity in this phase of the disease. Nowadays, there is not much evidence in the Spanish and international literature regarding the structure and how to achieve these objectives in the UERCA. From the ERCA working group of the Spanish Society of Nephrology (SEN), this project is promoted to improve care for ERCA patients through the definition of quality standards for the operation of the UERCA. MATERIAL AND METHODS: An initial proposal for quality standards concerning the operation of the UERCA was configured through consultation with the main sources of references and the advice of an expert working group through face-to-face and telematic meetings. Base on this initial proposal of standards, a survey was conducted and sent it via email to 121 nephrology specialist and nursing professionals with experience in Spanish UERCA to find out, among others, the suitability of each standards, that is, its mandatory nature or recommendation as standards. The access to the survey was allowed between July 16th, 2018, until September 26th, 2018. RESULTS: A total of 95 (78.5%) professionals participated out of the 121 who were invited to participate. Of these, 80 of the participants were nephrology specialists and 15 nursing professionals, obtaining a varied representation of professionals from the Spanish geography. After analyzing the opinions of these participants, the standards were defined to a total of 68, 37 of them (54.4%) mandatory and 31 of them (45.5%) recommended. Besides, it was observed that the volume of patients attended in the UERCA is usually above 100 patients, and the referral criteria is generally below 25-29 mL/min/1.73 m2 of glomerular filtration. CONCLUSIONS: This work constitutes a first proposal of quality standards for the operation of UERCA in Spain. The definition of these standards has made it possible to establish the bases for the standardization of the organization of UERCA, and to subsequently work on the configuration of a standards manual for the accreditation of ERCA Units.

A randomized controlled study on the effects of acetate-free biofiltration on organic anions and acid-base balance in hemodialysis patients.

Metabolic acidosis correction is achieved by the transfer of bicarbonate and other buffer anions in dialysis. The aim of this study was to evaluate changes in the main anions of intermediary metabolism on standard hemodiafiltration (HDF) and on acetate-free biofiltration (AFB). A prospective, in-center, crossover study was carried out with 22 patients on maintenance dialysis. Patients were randomly assigned to start with 12 successive sessions of standard HDF with bicarbonate (34 mmol/L) and acetate dialysate (3 mmol/L) or 12 successive sessions of AFB without base in the dialysate. Acetate increased significantly during the standard HDF session from 0.078 ± 0.062 mmol/L to 0.156 ± 0.128 mmol/L (P < 0.05) and remained unchanged at 0.044 ± 0.034 mmol and 0.055 ± 0.028 mmol/L in AFB modality. Differences in the acetate levels were observed at two hours (P < 0.005), at the end (P < 0.005) and thirty minutes after the session between HDF and AFB (P < 0.05). There were significantly more patients above the normal range in HDF group than AFB group (68.1% vs 4.5% P < 0.005) postdialysis and 30 minutes later. Serum lactate and pyruvate concentrations decreased during the sessions without differences between modalities. Citrate decreased only in the AFB group (P < 0.05). Acetoacetate and betahydroxybutyrate increased in both modalities, but the highest betahydroxybutyrate values were detected in HDF (P < 0.05). The sum of postdialysis unusual measured organic anions (OA) were higher in HDF compared to AFB (P < 0.05). AFB achieves an optimal control of acid-base equilibrium through a bicarbonate substitution fluid. It also prevents hyperacetatemia and restores internal homeostasis with less production of intermediary metabolites.

Experiencia en hemodiálisis domiciliaria en España / Spanish home hemodialysis experience

Resumen Antecedentes: existe actualmente un interés creciente, a nivel mundial, por las posibilidades que ofrece la hemodiálisis domiciliaria, la cual se encuentra más extendida en países del norte de Europa, Canadá, Reino Unido, Estados Unidos, Australia y Nueva Zelanda. En España, ha crecido de manera muy lenta, excepto en determinadas regiones como la provincia de Castellón, donde hemos puesto especial interés en la expansión de las técnicas dialíticas domiciliarias. Objetivo: describir la experiencia en el programa de hemodiálisis domiciliaria del Hospital General de Castellón. Metodología: estudio descriptivo de los pacientes incluidos en el programa de hemodiálisis domiciliaria del Hospital General de Castellón, desde su inicio en enero del 2008 hasta diciembre del 2017. Resultados: en su conjunto, entrenamos a 41 pacientes, de los que 36 llegaron a hemodializarse en casa (régimen corto-diario). La edad de los pacientes era 58,3±13,4 años; y el índice de Charlson, 4,1±1,6. 62 % de los pacientes eran hombres, 25,6 % padecían diabetes mellitus; 15,4 % tenían diagnóstico de insuficiencia cardíaca y 32 % eran portadores de fístula de hemodiálisis. El 38,5 % de los pacientes en edad laboral estaba activo. Obtuvimos una supervivencia técnica considerando el evento muerte+fallo técnico, censurando el trasplante, del 79,4 % al año, 75,2 % a los 2 años y 42,1 % a los 5 años. En el análisis univariante, resultaron determinantes la edad, la presencia de diabetes mellitus y la presencia de insuficiencia cardíaca. En el análisis multivariante, solo se mantuvo la insuficiencia cardíaca. Las reducciones semanales de fósforo y beta-2-microglobulina fueron significativamente mayores con hemodiálisis corta diaria, en comparación con la hemodiafiltración on-line. La hemodiafiltración on-line fue superior en la reducción semanal a partir de los 17 800 daltons para la mioglobina. Conclusiones: la hemodiálisis domiciliaria es una técnica posible que ofrece al paciente una adecuada reinserción sociolaboral, buenos niveles de reducción semanal de toxinas urémicas y una aceptable supervivencia técnica en el tiempo.

Abstract Background: There is currently a growing interest, worldwide, for the possibilities offered by home hemodialysis, which is more widespread in northern European countries, Canada, the United Kingdom, the United States, Australia and New Zealand. In Spain, it has grown very slowly, except in certain regions such as the province of Castellón, where we have placed special interest in the expansion of home dialysis techniques. Objective: To describe the experience in the Home Hemodialysis program of the Hospital General de Castellón. Methodology: Descriptive study of the patients included in the home hemodialysis program of the Hospital General de Castellón, from its beginning in January 2008 to December 2017. Results: As a whole, we trained 41 patients, of whom 36 came to hemodialysis at home (short-day regimen). Age 58,3±13,4 years, Charlson index 4,1±1,6, 62 % men, 25,6 % with diabetes mellitus, 15,4 % with diagnosis of heart failure, 32 % with hemodialysis fistula, 38,5 % of working-age patients were active. We obtained a technical survival considering the event death+technical failure, censoring transplant of 79,4 % a year, 75,2 % at 2 years and 42,1 % at 5 years, resulting determinants of the event in the univariate analysis: age, presence of diabetes mellitus and presence of heart failure, and only heart failure in the multivariate. The weekly reductions of phosphorus and beta-2-microglobulin were significantly greater with daily short hemodialysis with respect to on-line haemodiafiltration. Being the on-line hemodiafiltration superior in the weekly reduction from the 17800 daltons of myoglobin. Conclusions: Home hemodialysis is a possible technique that offers the patient an adequate social-labor reintegration with good levels of weekly reduction of uraemic toxins and an acceptable technical survival over time.

Evaluation of coagulation and anti-Xa factor when using a heparin-coated AN69ST® dialyser.

BACKGROUND: Hemodialysis systems are potentially thrombogenic, so it is routinely used anticoagulation. Its prescription is with risks though which the recommendations regarding the scheduled dose are still based on very different criteria. METHODS: We performed a randomized, crossover pilot study. Six patients underwent six sessions of post-dilution hemodiafiltration with polysulfone HF80® dialyzer and standard anticoagulation with nadroparin, and six sessions with heparin-coated poliacrylonitrile AN69ST® membrane without using systemic anticoagulation. Dialyser and the extracorporeal circuit clotting grade was evaluated through visual scale every hour and coagulation parameters like anti-Xa factor. Our endpoint was to assess anti-Xa activity without differences in the rate of massive clotting between the two groups. RESULTS: No complete or grade 4 dialyzer clotting occurred in any of 36 sessions with each dialyzer. A partial lower 25% (grade 1-2) dialyzer clotting was in 32 (89.7%) AN69ST® sessions and 35 (97.2%) with the usual dialyzer and upper 25% (grade 3-4) in 4 (11.1%) AN69ST® sessions and 1 (2.8%) dialysis session with heparin. Arterial chamber blood coagulation was not greater than 25% (grade 3 and 4) in any of the studied sessions and the venous chamber in only 1 (2.8%) session with the usual dialyzer and 3 (8.4%) with no differences AN69ST® between the two dialyzers. The activated partial thromboplastin time at two hours showed differences between techniques related to administration of low molecular weight heparin (33.3 ± 2.7s with polysulfone and 27.5 ± 2.3s in AN69ST®; P < 0.05) which remained significant at the end of the session (29.8 ± 2.1s with polysulfone and 27.2 ± 1.8s with AN69ST®; P < 0.05). Anti-Xa factor activity was maximal two hours after administration of nadroparin, with differences between the two dialyzers (0.46 ± 0.13 IU / ml in dialysis with polysulfone and 0.04 ± 0.04 IU / ml with AN69ST®p<0.005) and went down after 4 hours (0.17 ± 0.12 IU / ml in dialysis with polysulfone and 0.02 ± 0.03 IU / ml in AN69ST®; p<0.05). One patient in dialysis AN69ST®; had an adverse reaction characterized by generalized pruritus and was excluded from the study, by withdrawing the consent in the first session. CONCLUSION: We demonstrate the low thrombogenicity of the AN69ST®; dialyzer that allows post-dilution hemodiafiltration sessions without systemic anticoagulation, and without increasing the frequency of severe clotting events compared to HF80®; dialyzer with nadroparin and with less risk of bleeding by not modifying the anti-Xa factor activity.