The effects of medium cut-off and high-flux membranes on activated clotting time of patients on hemodialysis.

Introduction: The interaction between blood and dialysis membrane increases the risk of clot formation. Membrane properties can interfere with coagulation activation during dialysis. Heparin is usually used to ensure anticoagulation, which can be monitored by the Activated Clotting Time (ACT) test. The purpose of this study was to compare the ACT of patients with chronic kidney disease (CKD) undergoing hemodialysis with high-flux (HF) and medium cut-off (MCO) membranes. Methods: This is a prospective, randomized, crossover study in which 32 CKD patients were dialyzed for 12 weeks with each membrane. Blood clotting measured by ACT was evaluated at the beginning, 2nd, and 4th hour of the dialysis session. Throughout the study, there were no changes in the dose or administration method of heparin. Results: Patients mainly were middle-aged, non-black males on hemodialysis for eight years. Before randomization, ACT values were 132 ± 56, 195 ± 60, and 128 ± 32 seconds at pre-heparinization, 2nd and 4th hour, respectively. After 12 weeks, ACT values in HF and MCO groups were 129 ± 17, 205 ± 65 and 139 ± 38 seconds, and 143 ± 54, 219 ± 68 and 142 ± 45 seconds, respectively. An ANOVA model adjusted and unadjusted for repeated measures showed a significant time but no treatment or interaction effects. In an additional paired-sample analysis, no difference between ACT values of HF and MCO Groups was observed. Discussion and Conclusion: There was no difference regarding the ACT test during dialysis therapy using HF or MCO membranes. This data suggests that no adjustment in the dose or administration method of heparin is necessary with the use of MCO dialysis membranes.

Medium Cutoff Versus High-Flux Hemodialysis Membranes and Clinical Outcomes: A Cohort Study Using Inverse Probability Treatment Weighting.

Rationale & Objective: This study investigated the effects on patients' outcomes of using medium cutoff (MCO) versus high-flux (HF) dialysis membranes. Study Design: A retrospective, observational, multicenter, cohort study. Setting & Participants: Patients aged greater than 18 years receiving hemodialysis at the Baxter Renal Care Services dialysis network in Colombia. The inception of the cohort occurred from September 1, 2017, to November 30, 2017, with follow-up to November 30, 2019. Exposure: The patients were divided into 2 cohorts according to the dialyzer used at the inception: (1) MCO membrane or (2) HF membrane. Outcomes: Primary outcomes were the hospitalization rate from any cause and hospitalization days per patient-year. Secondary outcomes were acute cardiovascular events and mortality rates from any cause and secondary to cardiovascular causes. Laboratory parameters were assessed throughout the 2-year follow-up period. Analytical Approach: Descriptive statistics were used to report population characteristics. Inverse probability of treatment weighting was applied to each group before analysis. All categorical variables were compared using Pearson's χ2 test, and continuous variables were analyzed with the t test. Baseline differences between groups with a value of >10% were considered clinically meaningful. Laboratory variables were measured at 5 consecutive time points. A between-patient effect was analyzed using a split-plot factorial analysis of variance. Results: The analysis included 1,098 patients, of whom 564 (51.3%) were dialyzed with MCO membranes and 534 (48.7%) with HF membranes. Patients receiving hemodialysis with MCO membranes had a lower all-cause hospitalization incidence rate (IR) per patient-year (IR = 0.93; 95% CI, 0.82-1.03) than those receiving hemodialysis with HF membranes (IR = 1.13; 95% CI, 0.96-1.30), corresponding to a significant incident rate ratio (MCO/HF) of 0.82 (95% CI, 0.68-0.99; P = 0.04). The frequency of nonfatal cardiovascular events showed statistical significance, with a lower incidence in the MCO group (incident rate ratio = 0.66; 95% CI, 0.46-0.96; P = 0.03). No statistically significant differences in all-cause time until death were observed (P = 0.48). Albumin levels were similar between the 2 dialyzer cohorts. Limitations: Despite the robust statistical analysis, there remains the possibility that unmeasured variables may still generate residual imbalance and, therefore, skew the results. Conclusions: The incidences of hospitalization and cardiovascular events in patients receiving hemodialysis were lower when dialyzed with MCO membranes than HF membranes. A randomized controlled trial would be desirable to confirm these results. Trial Registration: Clinical Trials.gov, ISRCTN12403265.

Impact of hemodialysis and post-dialysis period on granular activity levels.

BACKGROUND: Physical activity (PA) is typically lower on hemodialysis (HD) days. Albeit intradialytic inactivity is expected, it is unknown whether recovery after HD contributes to low PA. We investigated the impact of HD and post-HD period on granular PA relative to HD timing. METHODS: We used baseline data from the HDFIT trial conducted from August 2016 to October 2017. Accelerometry measured PA over 1 week in patients who received thrice-weekly high-flux HD (vintage 3 to 24 months), were clinically stable, and had no ambulatory limitations. PA was assessed on HD days (0 to ≤24 h after start HD), first non-HD days (> 24 to ≤48 h after start HD) and second non-HD day (> 48 to ≤72 h after start HD). PA was recorded in blocks/slices: 4 h during HD, 0 to ≤2 h post-HD (30 min slices), and > 2 to ≤20 h post-HD (4.5 h slices). Blocks/slices of PA were captured at concurrent/parallel times on first/second non-HD days compared to HD days. RESULTS: Among 195 patients (mean age 53 ± 15 years, 71% male), step counts per 24-h were 3919 ± 2899 on HD days, 5308 ± 3131 on first non-HD days (p < 0.001), and 4926 ± 3413 on second non-HD days (p = 0.032). During concurrent/parallel times to HD on first and second non-HD days, patients took 1308 and 1128 more steps (both p < 0.001). Patients took 276 more steps and had highest rates of steps/hour 2-h post-HD versus same times on first non-HD days (all p < 0.05). Consistent findings were observed on second non-HD days. CONCLUSIONS: PA was higher within 2-h of HD versus same times on non-HD days. Lower PA on HD days was attributable to intradialytic inactivity. The established PA profiles are of importance to the design and development of exercise programs that aim to increase activity during and between HD treatments. TRIAL REGISTRATION: HDFIT was prospectively registered 20 April 2016 on ClinicalTrials.gov (NCT02787161).

Prognostic effect of high-flux hemodialysis in patients with chronic kidney disease

We investigated the prognostic effects of high-flux hemodialysis (HFHD) and low-flux hemodialysis (LFHD) in patients with chronic kidney disease (CKD). Both an electronic and a manual search were performed based on our rigorous inclusion and exclusion criteria to retrieve high-quality, relevant clinical studies from various scientific literature databases. Comprehensive meta-analysis 2.0 (CMA 2.0) was used for the quantitative analysis. We initially retrieved 227 studies from the database search. Following a multi-step screening process, eight high-quality studies were selected for our meta-analysis. These eight studies included 4967 patients with CKD (2416 patients in the HFHD group, 2551 patients in the LFHD group). The results of our meta-analysis showed that the all-cause death rate in the HFHD group was significantly lower than that in the LFHD group (OR=0.704, 95%CI=0.533-0.929, P=0.013). Additionally, the cardiovascular death rate in the HFHD group was significantly lower than that in the LFHD group (OR=0.731, 95%CI=0.616-0.866, P<0.001). The results of this meta-analysis clearly showed that HFHD decreases all-cause death and cardiovascular death rates in patients with CKD and that HFHD can therefore be implemented as one of the first therapy choices for CKD.

Corrección de la hiperfosforemia en pacientes con enfermedades renales crónicas tratados con hemodiálisis de alto flujo de larga duración / Correction of hyperphosphoremia in patients suffering chronic renal diseases and treated with long duration and high flux dialysis

Introducción: la hemodiálisis de alto flujo origina mayor remoción de moléculas grandes y pequeñas, por lo que incrementa su aclaramiento y se obtiene una mejoría ostensible en las personas tratadas. Teniendo en cuenta que la remoción del fósforo depende de su cinética, esta técnica permite lograr su corrección, más si la combinamos con una mayor duración y frecuencia de las sesiones de diálisis. Objetivo: evaluar la corrección de la hiperfosforemia con la hemodiálisis de alto flujo y de larga duración. Métodos: se realizó un estudio de intervención experimental en 2 grupos: estudio y control, elegidos por el método aleatorio simple 12 pacientes que tenían elevadas las cifras de fósforo. El grupo I recibió hemodiálisis de alto flujo de larga duración 18 h semanales utilizando dializadores con membrana de polisulfona de alto flujo y el grupo II, hemodiálisis convencional de bajo flujo 12 h semanales de tratamiento. Ambos con seguimiento clínico-humoral mensual. Fueron analizadas las variables de respuesta primaria y secundaria dadas por los niveles de fósforo, calcio, producto fosfocálcico, KT/V, albúmina, hemoglobina y morbilidad; los datos fueron procesados mediante el paquete estadístico SPSS versión 15.0. Resultados: En el grupo estudio hubo una disminución del fósforo sérico en 0,36 mmol/L, el calcio y el producto fosfocálcico disminuyeron en el tiempo en 9,2 porciento y 23,90 por ciento, respectivamente, al final del estudio. No existió correlación entre el tiempo de tratamiento (diálisis) y la hiperfosforemia, con una correlación lineal no paramétrica de Spearman de -0,09 y sin significación estadística. El 66,7 por ciento presentó calambres y el 50 porciento hipotensión como morbilidad. Conclusión: la hemodiálisis de alto flujo y larga duración disminuye los niveles séricos de fósforo y mejora los niveles de albúmina, calcio, metabolismo fosfocálcico y KT/V en los pacientes en hemodiálisis

Introduction: high flux hemodialysis causes major removal of big and small molecules, so the clearing increases and the treated people remarkably improves. Taking into account that excretion of phosphorus depends on its kinetics, this technique allows correcting it, mainly if combined with long duration and high frequency dialysis. Objective: to evaluate the correction of hyperphosphoremia based on long duration high flux hemodialysis. Methods: an experimental intervention study was conducted in two groups, namely, the study and the control groups in which 12 patients, who were selected by the simple random method, were distributed. They presented with high phosphorus content figures. Group I was treated with long duration high flux hemodialysis for 18 hours every week by using high flux polysulphone membrane dialyzers. Group II underwent conventional low flux hemodialysis for 12 hours a week. Both groups were clinically and humorally followed-up monthly. The primary and secondary response variables depending on the phosphorous, calcium, calcium phosphate product, KT/V, albumin, hemoglobin and morbidity levels were analyzed. Data were processed using SPPS statistical package, 15.0 version. Results: the study group lowered the serum phosphorus by 0.36 mmol/L, calcium and calcium phosphate product decreased by 9.2 percent and 23.90 percent respectively at the end of the study. There was no correlation between the length of treatment (dialysis) and hyperphosphoremia; Spearman's non-parametric linear correlation was -0.09 and there was no statistical significance. Of the patients, 66.7 percent had cramps and 50 percent had hypotension as morbidity. Conclusions: long duration high flux hemodialysis reduces the serum phosphorus levels and improves albumin, calcium, calcium phosphate product metabolism and KT/V in patients on hemodialysis