Utilidad del sistema de recirculación de adsorbentes moleculares en la falla hepática: "diálisis hepática" / Usefulness of the molecular adsorbent recirculating system in liver failure: "liver dialysis"

INTRODUCCIÓN. La falla hepática ya sea aguda o crónica reagudizada representa un reto para el clínico ya que sus complicaciones conllevan una gran mortalidad, esto se ve aún más complicado ya que las opciones terapéuticas son limitadas, incluso muchas veces no se puede acceder a un programa de trasplante hepático oportuno que mejore la sobrevida de estos pacientes, es así que se ha desarrollado un sistema de "diálisis" hepática conocido como sistema de recirculación de adsorbentes moleculares el cual hace un efecto de detoxificación para eliminar sustancias que generan una noxa en el cuerpo humano. OBJETIVO. Entender la utilidad del sistema recirculante molecular adsorbente en la falla hepática, conocer sus indicaciones y complicaciones. METODOLOGÍA. Se realizó una revisión de la literatura con un enfoque descriptivo, retrospectivo cualitativo no experimental, de documentos que tratan sobre la utilización del sistema MARS para tratar la falla hepática, con evidencia desde el año 2004 hasta el 2021. La revisión bibliográfica se llevó a cabo en bases de datos como Pubmed, Embase, BVS, Google Scholar y Elsevier. RESULTADOS. Se identificaron 30 artículos que cumplieron criterios de inclusión de un grupo original de 343 artículos revisados. Se ha determinado que la evidencia sobre este sistema está compuesta sobre todo por reportes de caso y son pocos los ensayos controlados aleatorizados que empleen su uso, sin embargo, se ha podido determinar que este sistema es un puente al trasplante renal mientras se estabiliza al paciente en la Unidad de Cuidados Intensivos, disminuye los marcadores de falla hepática. CONCLUSIÓN. En Latinoamérica su uso es casi nulo de ahí la necesidad de entender el mecanismo de este novedoso sistema.

INTRODUCTION. Hepatic failure, whether acute or chronic, represents a challenge for the clinician since its complications entail a great mortality, this is even more complicated since the therapeutic options are limited, even many times it is not possible to access a timely liver transplant program to improve the survival of these patients, Thus, a hepatic "dialysis" system known as molecular adsorbent recirculation system has been developed, which has a detoxification effect to eliminate substances that generate a noxa in the human body. OBJECTIVE. To understand the usefulness of the molecular adsorbent recirculating system in liver failure, to know its indications and complications. METHODOLOGY. A literature review was performed with a descriptive, retrospective qualitative non-experimental qualitative approach, of papers dealing with the use of the MARS system to treat liver failure, with evidence from 2004 to 2021. The literature review was conducted in databases such as Pubmed, Embase, BVS, Google Scholar and Elsevier. RESULTS. Thirty articles were identified that met inclusion criteria from an original group of 343 articles reviewed. It has been determined that the evidence on this system is mainly composed of case reports and there are few randomized controlled trials that employ its use, however, it has been determined that this system is a bridge to renal transplantation while the patient is stabilized in the Intensive Care Unit, decreasing the markers of liver failure. CONCLUSIONS. In Latin America its use is almost null, hence the need to understand the mechanism of this novel system.

Evaluation du statut martial des hémodialyses suivis au CNHU-HKM de Cotonou

Introduction : Le but de ce travail est d'évaluer l'état martial des hémodialysés du CNHU-HKM de Cotonou. Patient et Méthodes : Il s'agit d'une étude transversale à visée descriptive et analytique, réalisée en janvier 2017 dans l'Unité d'Hémodialyse du Centre National Hospitalier et Universitaire Hubert Koutoukou MAGA (CNHU-HKM). Ont été inclus, les patients hémodialysés chroniques, en dialyse de plus de 3 mois et âgés d'au moins 18 ans, sans pathologie intercurrente et non hospitalisés dans les 4 dernières semaines. L'évaluation de l'anémie a porté sur l'hémoglobine (g/dl), la ferritinémie (ng/ml) et le coefficient de saturation de la transferrine (CST). L'analyse des données a été faite au moyen des logiciels Excel 2013 et SPSS ver 8.0. Résultats : Au total, 190 hémodialysés ont été retenus, l'âge moyen était de 48,81±12.7 avec un sex-ratio de 1,71 et une ancienneté en dialyse de 68,25± 59,5 mois. Le taux moyen d'hémoglobine était de 8,6 ± 1,8 g/dl avec une ferritinemie moyenne de 1056,60± 1388,60 µg/l. La prévalence de l'anémie était de 91,6%. Parmi les patients, 23,7% avaient une ferritinemie entre 300 et 500 ng/dl et 66,8% avaient une ferritinemie élevée. Le CST était bas chez 69 patients soit 36,3% .Tous nos patients étaient sous EPO 4000 ui/semaine et la pluspart ont une supplémentation en fer. Discussion et Conclusion: Le pourcentage de nos patients répondant aux recommandations concernant l'anémie chez les hémodialysés est strictement inferieur aux données de la littérature. La ferritinemie de la moyenne de nos patients est supérieur aux normes, ce qui pourrait les exposer aux complications d'une surcharge ferrique

Effect of a rosmarinic acid supplemented hemodialysis fluid on inflammation of human vascular endothelial cells

Chronic systemic inflammation and repetitive damage of vascular endothelia by incompatible dialysis system are probable causes of cardiovascular disease in patients on dialysis. The present study aimed to assess in vitro biocompatibility and anti-inflammatory effect of hemodialysis fluid supplemented with rosmarinic acid (RA) using human umbilical vein endothelial cells (HUVEC). HUVECs (5×106 cells/mL) were pre-exposed to 1 μg/mL of lipopolysaccharides (LPS) and incubated with RA-supplemented hemodialysis fluid (HDF). Cytotoxicity was assessed qualitatively by morphologic assessment and quantitatively by MTT assay. Expressions of proinflammatory mediators were assessed using quantitative real-time PCR and production of NO was quantified. Phosphorylation of AKT and nuclear localization of nuclear factor kappa B (NF-κB) were examined using western blotting. Exposure of HUVECs to RA-supplemented HDF had no influence on morphology and viability. Inhibition of proinflammatory mediator production in HUVECs by RA supplementation to HDF was significant in a dose-dependent manner. Exposure to RA-supplemented HDF resulted in a decrease in nitric oxide synthase expression and reduction of NO production in LPS-stimulated HUVECs. RA supplementation of HDF suppressed Akt activation in LPS-stimulated HUVECs. In addition, the level of cellular IκB was increased in parallel to a reduced nuclear translocation of NF-κB in LPS-induced endothelial cells. Our results suggest that RA-supplemented HDF is biocompatible and significantly suppressed inflammation induced in endothelial cells. In this respect, the use of HDF supplemented with RA could alleviate inflammation and improve long-term treatment of patients with renal failure on dialysis. Further clinical studies are required to confirm the effects.

The Effect of Dialysate Flow Rate on Dialysis Adequacy and Fatigue in Hemodialysis Patients

PURPOSE: In this single repeated measures study, an examination was done on the effects of dialysate flow rate on dialysis adequacy and fatigue in patients receiving hemodialysis. METHODS: This study was a prospective single center study in which repeated measures analysis of variance were used to compare Kt/V urea (Kt/V) and urea reduction ratio (URR) as dialysis adequacy measures and level of fatigue at different dialysate flow rates: twice as fast as the participant’s own blood flow, 500 mL/min, and 700 mL/min. Thirty-seven hemodialysis patients received all three dialysate flow rates using counterbalancing. RESULTS: The Kt/V (M±SD) was 1.40±0.25 at twice the blood flow rate, 1.41±0.23 at 500 mL/min, and 1.46±0.24 at 700 mL/min. The URR (M±SD) was 68.20±5.90 at twice the blood flow rate, 68.67±5.22 at 500 mL/min, and 70.11±5.13 at 700 mL/min. When dialysate flow rate was increased from twice the blood flow rate to 700 mL/min and from 500 mL/min to 700 mL/min, Kt/V and URR showed relative gains. There was no difference in fatigue according to dialysate flow rate. CONCLUSION: Increasing the dialysate flow rate to 700 mL/min is associated with a significant nicrease in dialysis adequacy. Hemodialysis with a dialysate flow rate of 700 mL/min should be considered in selected patients not achieving adequacy despite extended treatment times and optimized blood flow rate.

Diagnostic accuracy of the defining characteristics of the excessive fluid volume diagnosis in hemodialysis patients / Acurácia diagnóstica das características definidoras do diagnóstico volume de líquidos excessivo de pacientes em hemodiálise / La exactitud diagnóstica de las características definidoras del diagnóstico volumen de líquidos excesivo de pacientes en hemodiálisis

Objective: to evaluate the accuracy of the defining characteristics of the excess fluid volume nursing diagnosis of NANDA International, in patients undergoing hemodialysis. Method: this was a study of diagnostic accuracy, with a cross-sectional design, performed in two stages. The first, involving 100 patients from a dialysis clinic and a university hospital in northeastern Brazil, investigated the presence and absence of the defining characteristics of excess fluid volume. In the second step, these characteristics were evaluated by diagnostic nurses, who judged the presence or absence of the diagnosis. To analyze the measures of accuracy, sensitivity, specificity, and positive and negative predictive values were calculated. Approval was given by the Research Ethics Committee under authorization No. 148.428. Results: the most sensitive indicator was edema and most specific were pulmonary congestion, adventitious breath sounds and restlessness. Conclusion: the more accurate defining characteristics, considered valid for the diagnostic inference of excess fluid volume in patients undergoing hemodialysis were edema, pulmonary congestion, adventitious breath sounds and restlessness. Thus, in the presence of these, the nurse may safely assume the presence of the diagnosis studied.

Objetivo: avaliar a acurácia das características definidoras do diagnóstico de enfermagem volume de líquidos excessivo da NANDA Internacional, em pacientes submetidos à hemodiálise. Método: trata-se de um estudo de acurácia diagnóstica, com delineamento do tipo transversal, realizado em duas etapas. A primeira envolveu 100 pacientes de uma clínica de diálise e um hospital universitário do Nordeste do Brasil, investigando-se sobre a presença e ausência das características definidoras do volume de líquidos excessivo. Na segunda etapa, estas características foram avaliadas por enfermeiros diagnosticadores, que julgaram a presença ou ausência do diagnóstico. Para análise das medidas de acurácia foram calculados sensibilidade, especificidade e valores preditivos positivo e negativo. Aprovado pelo Comitê de Ética em Pesquisa sob o protocolo nº 148.428. Resultados: o indicador mais sensível foi o edema e os mais específicos foram congestão pulmonar, ruídos respiratórios adventícios e agitação. Conclusão: as características definidoras mais acuradas, consideradas válidas para a inferência diagnóstica do volume de líquidos excessivo em pacientes submetidos à hemodiálise são edema, congestão pulmonar, ruídos respiratórios adventícios e agitação. Assim, na presença destas, o enfermeiro poderá traçar, com segurança, a presença do diagnóstico estudado.

Objetivo: evaluar la exactitud de las características definidoras del diagnóstico de enfermería volumen de líquidos excesivo, de la NANDA Internacional, en pacientes sometidos a hemodiálisis. Método: se trata de un estudio de exactitud diagnóstica, con diseño de tipo transversal, realizado en dos etapas. En la primera participaron 100 pacientes de una clínica de diálisis y un hospital universitario del Noreste de Brasil; se investigó la presencia y ausencia de las características definidoras del volumen de líquidos excesivo. En la segunda etapa, estas características fueron evaluadas por enfermeros diagnosticadores, los que juzgaron la presencia o ausencia del diagnóstico. Para analizar las medidas de exactitud fueron calculados: sensibilidad, especificidad y, valores predictivos positivo y negativo. Estudio aprobado por el Comité de Ética en Investigación con el protocolo nº 148.428. Resultados: el indicador más sensible fue el edema y los más específicos fueron: congestión pulmonar, ruidos respiratorios agregados y agitación. Conclusión: las características definidoras más exactas, consideradas válidas para la inferencia diagnóstica del volumen de líquidos excesivo, en pacientes sometidos a hemodiálisis fueron: edema, congestión pulmonar, ruidos respiratorios agregados y agitación. Así, en la presencia de estas características, el enfermero podrá detectar, con seguridad, la presencia del diagnóstico estudiado.

Risk of hypoglycemia during hemodialysis in diabetic patients is related to lower pre-dialysis glycemia

Objective To compare the occurrence of hypoglycemia during hemodialysis in chronic kidney disease diabetic patients who present different levels of pre-dialysis glycemia both when using dialysis solutions with and without glucose. Subjects and methods Twenty type 2 diabetic patients in maintenance hemodialysis were submitted to three dialysis sessions (at a 7-day interval each) with dialysis solutions without glucose, with glucose at 55 mg/dL, and at 90 mg/dL subsequently. Blood glucose levels were measured immediately pre-dialysis and at 4 moments during the session, and values under 70 mg/dL were considered as hypoglycemia. Results Average pre-dialysis glycemia was lower in those who presented intra-dialytic hypoglycemia than in those who did not, both in glucose-free (140.4 ± 50.7 vs. 277.7 ± 91.0 mg/dL; p = 0.005; 95%CI: 46.4 to 228.1) and in glucose 55 mg/dL (89.5 ± 10.6 vs. 229.7 ± 105.0 mg/dL; p < 0.05; 95%CI: 9.8 to 270.5). In patients with pre-dialysis glycemia under 140 mg/dL, average intradialytic glycemia was significantly lower than pre-dialysis glycemia only when using glucose-free dialysate (p < 0.0001; 95%CI: 29.9 to 56.0 - t-test). Hypoglycemia during dialysis was observed only when using glucose-free or glucose-poor dialysis solutions. Conclusions The use of glucose-free or glucose-poor dialysis solution presents a high risk of intradialytic hypoglycemia in diabetic renal patients, especially in those with presumed better glycemic control. .

Importancia sanitaria de Pseudomonas aeruginosa en agua de hemodiálisis y su desinfección / Health importance of Pseudomonas aeruginosa in hemodyalisis water and its disinfection

Introducción: la contaminación microbiológica de los sistemas de tratamiento de agua para hemodiálisis es un problema actual, sobre todo, por la persistencia de determinados microorganismos en la formación del biofilm, entre ellos Pseudomonas aeruginosa. Objetivo: actualizar los conocimientos sobre la importancia sanitaria de Pseudomonas aeruginosa y su desinfección en agua de hemodiálisis, que aporten criterios para la toma de decisiones adecuadas. Métodos: los datos se obtuvieron de organismos internacionales como son la Asociación para el Avance de Instrumentos Médicos y la Organización Internacional de Normalización, de criterios de expertos y de resultados de laboratorio y guías de trabajo. Síntesis de la información: existen diferentes manera de actuar sobre la contaminación bacteriana, uno de ellos es evitarla, que se puede lograr si ciertos elementos del sistema son mejorados para crear finalmente un flujo turbulento y evitar la presencia de biofilm, también puede lograrse con calor o con productos químicos desinfectantes que deben estar validados. Sin embargo, para evitar la presencia de Pseudomonas aeruginosa y otros microorganismos, hay que poner énfasis en la limpieza y desinfección de forma regular y preventiva de todas las partes de los sistemas de tratamiento y de distribución de agua y de las máquinas de hemodiálisis. Conclusiones: el proceso de desinfección en el caso de contaminación por Pseudomonas aeruginosa en una planta de tratamiento es casuístico, teniendo en cuenta la diversidad de sistemas de tratamiento de agua, sistemas de distribución, su tiempo de explotación y la necesidad de tomar medidas puntuales para cada una de estos(AU)

Introduction: microbiological contamination of the hemodialysis water treatment is a present problem mainly because of the persistence of certain microorganisms in the biofilm formation, such as the case of Pseudomonas aeruginosa. Objective: to update the knowledge on the health importance of Pseudomonas aeruginosa and their disinfection in hemodialysis water for adequate decision-making. Methods: data were taken from international bodies such as the Association for the Advancement of Medical Instruments, the International Standardization Organization, expert criteria and lab results as well as work guidelines. Information synthesis: there are different ways of acting upon the bacterial contamination; one of them is to prevent it. This can be accomplished if certain elements of the system are improved to create a turbulent flow that prevents the presence of biofilm; it may also be attained by using heat or disinfectant chemical products that should be validated. However, for the purpose of preventing the presence of Pseudomonas aeruginosa and other microorganisms, emphasis must be made on regular and preventive cleaning and disinfection of all the parts of the water treatment and distribution systems and of the hemodialysis equipment. Conclusions: the process of disinfection of Pseudomonas aeruginosa in a water treatment plant is casuistic, taking into account the diversity of water treatment systems, distribution systems, operating time and need of taking point measures aimed at each of them(AU)

Desempeño analítico de los métodos de control de calidad de una solución concentrada para hemodiálisis / Analytical performance of the quality control methods in a concentrated solution for hemodialysis

Objetivo: evaluar el desempeño de los métodos de cuantificación de los iones sodio, potasio, cloruro, calcio y magnesio en una solución concentrada para hemodiálisis con bicarbonato. Métodos: los cinco métodos aparecen informados en la farmacopea británica. Para la verificación del desempeño, se utilizaron los parámetros, linealidad, exactitud y precisión. Se empleó el método de placebo enriquecido utilizando niveles de 60 a 140 por ciento de la concentración nominal de cada ion. Resultados: los cinco métodos resultaron lineales en el intervalo de concentraciones evaluadas, fueron precisos y exactos, con coeficientes de variación global menor que 1,75 por ciento, y una recuperación entre 100 ± 3 por ciento. Conclusiones: los métodos de cuantificación de los iones presentes en la solución concentrada para hemodiálisis con bicarbonato, permiten obtener resultados fiables en las condiciones analíticas practicadas en esta investigación(AU)

Objective: to evaluate the analytical performance of the sodium, potassium, chloride, calcium and magnesium ions quantification methods, in a concentrated solution with bicarbonate for hemodyalisis. Methods: the five analytical methods are reported on the official British pharmacopeia. The performance evaluation was made by verifying linearity, accuracy and precision. In all cases, the enriched placebo method was used, with concentration levels from 60 to 140 percent of the standard concentration value of each ion. Results: the five methods showed linearity in the evaluated concentration range; they were accurate and precise with global variation coefficients lower than 1.75 percent, and a recovery rate of 100 ± 3 percent. Conclusions: the quantification methods for the ions present in concentrated solution with bicarbonate for hemodialysis, allows obtaining reliable results under the analytical conditions used in this research(AU)

Cálculo de Kt/V em hemodiálise: comparação entre fórmulas / Calculation of Kt/V in haemodialysis: a comparison between the formulas

INTRODUÇÃO: A qualidade da diálise oferecida aos pacientes em diálise pode ser mensurada pelo Kt/V, o qual pode ser calculado de diversas maneiras. OBJETIVO: Comparar os resultados de Kt/V obtidos por meio das fórmulas de Lowrie (L) e de Daugirdas (D) com os resultados mensurados pelo monitor de clearence on-line - Online Clearence Monitor (OCM). MÉTODO: Estudo observacional transversal com 59 pacientes em hemodiálise (HD). Os dados foram coletados na mesma sessão de diálise: (ureia pré-diálise e pós-diálise) e o resultado de Kt/V foi obtido pelo OCM da máquina Fresenius 4008S (Fresenius Medical Care AG, Bad Homburg, Alemanha). RESULTADO: Foram analisadas 95 sessões, em que prevaleceu o sexo masculino, 56% (33), com idade média de 57 + 14 anos. A hipertensão arterial com 42% (25), diabetes com 12% (7) e glomerulonefrite com 8% (5) foram as causas mais frequentes da doença renal crônica (DRC). O Kt/V médio obtido pela fórmula de L, de D e pelo OCM foi de 1,31; 1,41 e 1,32, respectivamente. A comparação entre as fórmulas de L e D mostra que há diferença estatística p = 0,008 com a correlação de Pearson de 0,950. Entre D e OCM a diferença também é significativa: p = 0,011 e r = 0,346, provavelmente devido a perda convectiva, avaliada pela equação de D e não observadas por OCM e L. A comparação entre L e OCM não foi significativa p = 0,999 e r = 0,577. CONCLUSÃO: Os dados sugerem que o OCM pode ser utilizado como um norteador para ajuste da dose de diálise em tempo real.

INTRODUCTION: The quality of delivered dialysis can be measured by the Kt/V ratio, which can be calculated in various ways. OBJECTIVE: To compare the Kt/V ratio obtained with the formulas of Lowrie (L) and Daugirdas (D) with the results measured by an Online Clearance Monitor (OCM). Method: Observational, cross-sectional study of 59 patients on hemodialysis (HD). Data were collected in the same dialysis session (predialysis and postdialysis urea) and Kt/V was calculated by the OCM of the Fresenius 4008S machine (Fresenius Medical Care AG, Bad Homburg, Germany). RESULTS: A total of 95 sessions were assessed, with a predominance of males 56% (33), and a sample mean age of 57 + 14 years. Hypertension (42%; n = 25), diabetes (12%; n = 7) and glomerulonephritides (8%; n = 5) were the most frequent causes of chronic kidney disease (CKD). Mean Kt/V values obtained with the L and D formulas and the OCM were 1.31, 1.41 and 1.32, respectively. Comparison between the L and D formulas showed a statistically significant difference (p = 0.008), with a Pearson's correlation of 0.950. The difference between the D formula and the OCM was also significant (p = 0.011 and r = 0.346), probably due to convective loss, estimated by the D formula but not by the OCM and L formula. The difference between the L formula and the OCM was not significant (p = 0.999 and r = 0.577). CONCLUSION: These data suggest that the OCM can be used as a guide to the real-time adjustment of the dialysis dose.

Candida parapsilosis complex water isolates from a haemodialysis unit: biofilm production and in vitro evaluation of the use of clinical antifungals

Candida parapsilosis, currently divided into three distinct species, proliferates in glucose-rich solutions and has been associated with infections resulting from the use of medical devices made of plastic, an environment common in dialysis centres. The aims of this study were (i) to screen for Candida orthopsilosis and Candida metapsilosis (100 environmental isolates previously identified as C. parapsilosis), (ii) to test the ability of these isolates to form biofilm and (iii) to investigate the in vitro susceptibility of Candida spp biofilms to the antifungal agents, fluconazole (FLC) and amphotericin B (AMB). Isolates were obtained from a hydraulic circuit collected from a haemodialysis unit. Based on molecular criteria, 47 strains were re-identified as C. orthopsilosis and 53 as C. parapsilosis. Analyses using a formazan salt reduction assay and total viable count, together with microscopy studies, revealed that 72 strains were able to form biofilm that was structurally similar, but with minor differences in morphology. A microtitre-based colorimetric assay used to test the susceptibility of fungal biofilms to AMB and FLC demonstrated that the C. parapsilosis complex displayed an increased resistance to these antifungal agents. The results from these analyses may provide a basis for implementing quality controls and monitoring to ensure the microbiological purity of dialysis water, including the presence of yeast.

Effects of Lowering Dialysate Calcium Concentrations on Arterial Stiffness in Patients Undergoing Hemodialysis

BACKGROUND/AIMS: We assessed changes in hemodynamic and arterial stiffness parameters following reductions of dialysate calcium concentrations in patients undergoing hemodialysis. METHODS: In this prospective study, 20 patients on maintenance hemodialysis (10 females, 10 males) with dialysate calcium concentrations of 1.75 mmol/L were enrolled. At the start of the study, the dialysate calcium level was lowered to 1.50 mmol/L. Serial changes in biochemical, hemodynamic, and arterial stiffness parameters, including pulse wave velocity (PWV) and augmentation index (AIx), were assessed every 2 months for 6 months. We also examined changes in the calcification-inhibitory protein, serum fetuin-A. RESULTS: During the 6-month study period, serum total calcium and ionized calcium decreased consistently (9.5 +/- 1.0 to 9.0 +/- 0.7, p = 0.002 vs. 1.3 +/- 0.1 to 1.1 +/- 0.1, p = 0.035). Although no apparent changes in blood pressure were observed, heart-femoral PWW (hf-PWV) and AIx showed significant improvement (p = 0.012, 0.043, respectively). Repeated-measures ANOVA indicated a significant effect of lowering dialysate calcium on hf-PWV (F = 4.58, p = 0.004) and AIx (F = 2.55, p = 0.049). Accompanying the change in serum calcium, serum fetuin-A levels significantly increased (95.8 +/- 45.8 pmol/mL at baseline to 124.9 +/- 82.2 pmol/mL at 6 months, p = 0.043). CONCLUSIONS: Lowering dialysate calcium concentration significantly improved arterial stiffness parameters, which may have been associated with upregulation of serum fetuin-A.

Effect of chloride dialysate concentration on metabolic acidosis in aintenance hemodialysis patients

Hyperchloremia is one of the multiple etiologies of metabolic acidosis in hemodialysis (HD) patients. The aim of the present study was to determine the influence of chloride dialysate on metabolic acidosis control in this population. We enrolled 30 patients in maintenance HD program with a standard base excess (SBE) ≤2 mEq/L and urine output of less than 100 mL/24 h. The patients underwent dialysis three times per week with a chloride dialysate concentration of 111 mEq/L for 4 weeks, and thereafter with a chloride dialysate concentration of 107 mEq/L for the next 4 weeks. Arterial blood was drawn immediately before the second dialysis session of the week at the end of each phase, and the Stewart physicochemical approach was applied. The strong ion gap (SIG) decreased (from 7.5 ± 2.0 to 6.2 ± 1.9 mEq/L, P = 0.006) and the standard base excess (SBE) increased after the use of 107 mEq/L chloride dialysate (from -6.64 ± 1.7 to -4.73 ± 1.9 mEq/L, P < 0.0001). ∆SBE was inversely correlated with ∆SIG during the phases of the study (Pearson r = -0.684, P < 0.0001) and there was no correlation with ∆chloride. When we applied the Stewart model, we demonstrated that the lower concentration of chloride dialysate interfered with the control of metabolic acidosis in HD patients, surprisingly, through the effect on unmeasured anions.

Aluminio en pacientes con terapia de reemplazo renal crónico con hemodiálisis en dos unidades renales en Bogotá / Aluminium in chronic renal replacement therapy patients undergoing haemodialysis in two renal units in Bogotá

Objetivo Determinar las concentraciones de aluminio en suero de pacientes con terapia de reemplazo renal crónico con hemodiálisis y las concentraciones en agua de redes de distribución y diálisis en dos unidades renales en Bogotá. Material y Métodos Estudio descriptivo en 63 pacientes en hemodiálisis y 20 individuos sanos. Las concentraciones de aluminio se determinaron por espectrofotometría de absorción atómica horno de grafito con corrección de lámpara de deuterio. Resultados El promedio de las concentraciones de aluminio en suero de los pacientes fue de 26,5 µg/L (11,2 a 49,2 µg/L, DE=8,03), en individuos sanos de 8,05 µg/L (menor al Límite de Detección a 17,2 µg/L, DE=4,31), en agua de diálisis fue menor a 2 µg/L y en agua de las redes de distribución menor a 200 µg/L. Conclusiones Las concentraciones de aluminio en el agua de la red de distribución y diálisis estudiadas se encontraron por debajo de los valores establecidos internacionalmente indicando un adecuado tratamiento de las mismas. Igualmente las concentraciones de aluminio pre-HD y post-HD observadas en los pacientes se encontraron por debajo de las reportadas en la literatura. El consumo de hidróxido de aluminio aumenta significativamente la concentración de aluminio en suero. Variables como edad, género, estado civil y situación laboral no son factores de riesgo que alteren significativamente las concentraciones de aluminio en suero.

Objective Determining aluminium concentrations in the serum of patients undergoing chronic renal replacement therapy with haemodialysis and concentration in distribution network water and dialysis in two renal units in Bogotá. Material and Methods This was a descriptive study of 63 haemodialysed patients and 20 healthy subjects. Aluminium concentration was determined in water and serum using graphite furnace atomic absorption spectrometry with deuterium lamp background corrector. Results Average aluminium concentration was 26.5 µg/L in patients (ranging from 11.2 to 49.2 µg/L; 8.03 standard deviation) and 8.05 µg/L in healthy individuals (ranging from undetectable to 17.2 µg/L; 4.31 standard deviation). Aluminium concentration in dialysis water and distribution network water was below 2 µg/L and 200 µg/L, respectively. Conclusions Aluminium concentration in water and serum in this study was below international standard values, thereby indicating appropriate treatment. Additionally, aluminium concentration in pre-HD and post-HD sera was below that reported previously. Aluminium hydroxide uptake increases aluminium concentration in serum. Personal situation regarding age, gender, civil and work status were not risk factors determining aluminium concentrations in serum.

Application of Cystatin C Reduction Ratio to High-Flux Hemodialysis as an Alternative Indicator of the Clearance of Middle Molecules

BACKGROUND/AIMS: Although high-flux (HF) dialyzers with enhanced membrane permeability are widely used in current hemodialysis (HD) practice, urea kinetic modeling is still being applied to indicate the adequacy of both low-flux (LF) and HF HD. In comparison with urea (molecular weight, 60 Da) and beta2-microglobulin (beta2MG, 12 kDa), cystatin C (CyC, 13 kDa) is a larger molecule that has attractive features as a marker for assessing solute clearance. We postulated that CyC might be an alternative for indicating the clearance of middle molecules (MMs), especially with HF HD. METHODS: Eighty-nine patients were divided into LF and HF groups. Using single pool urea kinetic modeling, the urea reduction ratio (URR) and equilibrated Kt/Vurea (eKt/Vurea) were calculated. The serum CyC concentrations were measured using particle-enhanced immunonephelometry. As indices of the middle molecular clearance, the reduction ratios of beta2MG and CyC were calculated. RESULTS: The beta2MG reduction ratio (beta2MGRR) and CyC reduction ratio (CyCRR) were higher in the HF group compared to the LF group. However, the URR and eKt/Vurea did not differ between the two groups. The CyCRR was significantly correlated with the eKt/Vurea and beta2MGRR (r = 0.47 and 0.69, respectively, both p < 0.0001). CONCLUSIONS: Compared to the LF dialyzer, the HF dialyzer removed CyC and beta2MG more efficiently. Unlike the beta2MGRR, the CyCRR was correlated with the eKt/Vurea and beta2MGRR. This study suggests a role for the CyCRR as an alternative indicator of the removal of MMs.

Efeito benéfico da correção da acidose metabólica no estado nutricional de pacientes em hemodiálise / Beneficial effects of metabolic acidosis correction in hemodialysis patients

Objetivo: Avaliar o efeito da correção da acidose metabólica no estado nutricional de pacientes em hemodiálise. Métodos: Foram estudados, durante seis meses, 20 pacientes com acidose metabólica, definida pela média de tr~es mensurações de bicarbonato sérico pré-diálise <22 mEq/L. os pacientes dialisavam há, pelo menos, seis meses, utilizando bicarbonato de 35 mEq/L no dialisato. A correção da acidose metabólica foi feita mediante elevação do bicarbonato no dialisato para valores que não ultrapassaram 40 mEq/L, objetivando um bicarbonato sérico entre 22-26 mEq/L. Foram avaliados no início e no final do estudo: avaliação antropométrica, dietética, bioquímica e Avaliação subjetiva Global (ASG). Resultados: A avaliação nutricional na fase inicial do estudo demonstrou índice de massa corporal normal (24,23 +- 3,83 Kg/m²). A circunferência muscular do braço, a prega cutânea tricipital e a ASG classificaram homens e mulheres como desnutridos. Os consumos de calorias e proteínas foram 29,7 +- 10,1 Kcal?kg/dia e 1,31 +- 0,35 g/Kg/dia, respectivamente. A avaliação bioquímica observou albumina sérica normal e colesterol reduzido. Após correção, bicarbonato sérico e pH aumentaram de 18,2 +- 1,64 para 22 +- 1,70 (p<0,001), e de 7,32+- 0,45 para 7,37 +-0,41 (p<0,001), respectivamente. Houve melhora da ASG (21,7 +- 6,4 versus 16,8 +-6,6, p<0,0001) e aumento na ingestão calórica (1.892,61 +-454,30 versus 2.110,30 +-869,24, p<0,05). Conclusão: A suplementação de bicarbonato na solução de hemodiálise foi método efetivo para a correção da acidose metabólica, determinando aumento da ingestão calórica e melhora nos escores da ASG.

Objective: To evaluate the effect of correction of metabolic acidosis on nutritional status of hemodialysis patients. Methods: We studied for six months, 20 patients with metabolic acidosis, defined as the average of tr ~ s measurements of predialysis serum bicarbonate <22 mEq / L. patients receiving dialysis treatment for at least six months, using bicarbonate of 35 mEq / L in the dialysate. The correction of metabolic acidosis was observed in the high bicarbonate dialysate for values that exceeded 40 mEq / L, aiming for a serum bicarbonate between 22-26 mEq / L. Were assessed at baseline and at the end of the study: anthropometric, dietary, biochemical and Subjective Global Assessment (SGA). Results: The nutritional assessment in the initial phase of the study showed normal BMI (24.23 + - 3.83 kg / m²). The arm muscle circumference, triceps skinfold and the ASG men and women classified as malnourished. The intake of calories and protein were 29.7 + - 10.1 Kcal? Kg / day and 1.31 + - 0.35 g / kg / day, respectively. The biochemical evaluation showed normal serum albumin and low cholesterol. After correction, serum bicarbonate and pH increased from 18.2 + - 1.64 for 22 + - 1.70 (p <0.001), and 7.32 + - 0.45 to 7.37 + -0.41 ( p <0.001), respectively. There was improvement in ASG (21.7 + - 6.4 versus 16.8 + -6.6, p <0.0001) and increased caloric intake (1892.61 + -454.30 vs 2110.30 + -869 , 24, p <0.05). Conclusion: Supplementation of bicarbonate in the dialysis solution was an effective method for correction of metabolic acidosis, determining increased caloric intake and improvement in the scores of the ASG.

Água para hemodiálise no estado do Rio de Janeiro: uma avaliação dos dados gerados pelo programa de monitoramento da qualidade nos anos de 2006-2007 / Hemodialysis water in the state of Rio de Janeiro: an evaluation of data generated by the program for monitoring quality in the years 2006-2007

No presente estudo, avaliamos a distribuição percentual dos resultados de análises fiscais da água em relação ao perfil das unidades e ao cumprimento das exigências de controle e manutenção dos sistemas de tratamento.

Delay in onset of metabolic alkalosis during regional citrate anti-coagulation in continous renal replacement therapy with calcium-free replacement solution.

Regional citrate anti-coagulation for continuous renal replacement therapy chelates calcium to produce the anti- coagulation effect. We hypothesise that a calcium-free replacement solution will require less citrate and produce fewer metabolic side effects. Fifty patients, in a Medical Intensive Care Unit of a tertiary teaching hospital (25 in each group), received continuous venovenous hemofiltration using either calcium-containing or calcium-free replacement solutions. Both groups had no significant differences in filter life, metabolic alkalosis, hypernatremia, hypocalcemia, and hypercalcemia. However, patients using calcium-containing solution developed metabolic alkalosis earlier, compared to patients using calcium-free solution (mean 24.6 hours,CI 0.8-48.4 vs. 37.2 hours, CI 9.4-65, P = 0.020). When calcium-containing replacement solution was used, more citrate was required (mean 280ml/h, CI 227.2-332.8 vs. 265ml/h, CI 203.4-326.6, P = 0.069), but less calcium was infused (mean 21.2 ml/h, CI 1.2-21.2 vs 51.6ml/h, CI 26.8-76.4, P ≤ 0.0001).

Microbiological contamination of a hemodialysis center water distribution system / Contaminação microbiológica no sistema de distribuição de água de um centro de hemodiálise

The microbiological monitoring of the water used for hemodialysis is extremely important, especially because of the debilitated immune system of patients suffering from chronic renal insufficiency. To investigate the occurrence and species diversity of bacteria in waters, water samples were collected monthly from a hemodialysis center in upstate São Paulo and tap water samples at the terminal sites of the distribution system was sampled repeatedly (22 times) at each of five points in the distribution system; a further 36 samples were taken from cannulae in 19 hemodialysis machines that were ready for the next patient, four samples from the reuse system and 13 from the water storage system. To identify bacteria, samples were filtered through 0.22 µm-pore membranes; for mycobacteria, 0.45 µm pores were used. Conventional microbiological and molecular methods were used in the analysis. Bacteria were isolated from the distribution system (128 isolates), kidney machine water (43) and reuse system (3). Among these isolates, 32 were Gram-positive rods, 120 Gram-negative rods, 20 Gram-positive cocci and 11 mycobacteria. We propose the continual monitoring of the water supplies in hemodialysis centers and the adoption of effective prophylactic measures that minimize the exposure of these immunodeficient patients to contaminated sources of water.

O monitoramento microbiológico da água utilizada no procedimento de hemodiálise é de extrema importância, principalmente devido à imunodebilidade dos pacientes com insuficiência renal crônica. Nosso objetivo foi verificar qualitativa e quantitativamente a presença de bactérias na água de um centro de hemodiálise do interior do Estado de São Paulo. Foram realizadas 22 coletas de cada um dos cinco pontos do sistema de distribuição; 36 amostras de 19 máquinas de hemodiálise, prontas para utilização; quatro amostras do sistema de reuso e 13 amostras do sistema de armazenamento de água, empregando-se a técnica da membrana filtrante com poros de 0,22 µm para bactérias e de 0,45 µm para micobactérias. A identificação foi realizada através de métodos microbiológicos convencionais e de biologia molecular. Isolados bacterianos foram obtidos de sistema de distribuição (128), águas das máquinas (43) e sistema de reuso (3). Entre os isolados 32 foram de bacilos Gram-positivos, 120 bacilos Gram-negativos, 20 Cocos Gram-positivos e 11 micobactérias. Neste estudo, sugerimos que suprimentos de água para o Centro de Hemodiálise devam ser monitorados, adotando-se medidas profiláticas eficazes que minimizem a exposição destes pacientes imunodeficientes a fontes aquáticas ambientais contaminadas.

Effect of glucose peritoneal dialysates on the transmesothelial electrical resistance and cellular migration of monolayer human peritoneal mesothelial cell / 中南大学学报(医学版)

OBJECTIVE@#To investigate the effect of different concentrations of glucose peritoneal dialysates (PDS) on monolayer transmesothelial electrical resistance (TER) and migration ability of cultured human peritoneal mesothelial cells (HPMCs) to clarify the cause of peritoneal hyperpermeability state and ultrafiltration failure during prolonged peritoneal dialysis.@*METHODS@#HPMCs were cultured in a 1:1 mixture of DMEM and PDS containing 1.5%, 2.5%, and 4.25% glucose. Methyl thiazolyl tetrazolium (MTT) assay and TER were measured to determine the effect of glucose PDS on the proliferation and permeability of human peritoneal mesothelial monolayers, respectively. Wound-healing assay was used to confirm whether glucose could do harm to the migration of cells.@*RESULTS@#Proliferation of HPMCs was significantly suppressed by different glucose concentrations at 24 hours. TER decreased in a time- and concentration-dependent manner after culture with different concentrations of glucose PDS. Cells lost migration in the presence of high glucose after 24 hours, and most cells lost their normal morphology and became detached from plates after 48 hours of wounding.@*CONCLUSION@#High glucose in PDS can cause peritoneal damage by suppressing cell proliferation, inducing increase in paracellular permeability of HPMCs and inhibiting cell migration after damage, which may be responsible for peritoneal hyperpermeability and the development of ultrafiltration failure.