Renal Association Clinical Practice Guideline on Haemodialysis

Dialyzer surface area is a significant predictor of mortality in patients on hemodialysis: a 3-year nationwide cohort study

A target Kt/V of > 1.4 and use of a high-flux dialyzer are recommended for patients on hemodialysis. However, there is little information on the relationship between the dialyzer surface area and mortality in these patients. In this nationwide cohort study, we aimed to clarify this relationship by analyzing data from the Japanese Society for Dialysis Therapy for 2010–2013. We enrolled 234,638 patients on hemodialysis who were divided according to quartile for dialyzer surface area into the S group (small, < 1.5 m²), M group (medium, 1.5 m²), L group (large, 1.6 to < 2.0 m²), or XL group (extra-large, ≥ 2.0 m²). We assessed the association of each group with 3-year mortality using Cox proportional hazards models and performed propensity score matching analysis. By the end of 2013, a total of 53,836 patients on dialysis (22.9%) had died. There was a significant decrease in mortality with larger dialyzer surface areas. The hazard ratio (95% confidence interval) was significantly higher in the S group (1.15 [1.12–1.19], P < 0.0001) and significantly lower in the L group (0.89 [0.87–0.92] P < 0.0001) and XL group (0.75 [0.72–0.78], P < 0.0001) than in the M group as a reference after adjustment for all confounders. Findings were robust in several sensitivity analyses. Furthermore, the findings remained significant after propensity score matching. Hemodialysis using dialyzers, especially super high-flux dialyzers with a larger surface area might reduce mortality rates, and a surface area of ≥ 2.0 m² is superior, even with the same Kt/V.

Intraoperative Renal Replacement Therapy: Practical Information for Anesthesiologists

Previous publications regarding perioperative renal replacement therapy (RRT) have focused on the general care of the RRT-dependent patient and provided a broad overview of the various RRT modalities. The goal of this review article is to provide anesthesiologists with specific practical information regarding the possible intraoperative advantages and limitations of each modality, mandatory equipment to institute intraoperative therapy, and background knowledge necessary to communicate effectively with nephrologists and/or support staff regarding the intraoperative RRT goals.

Fungi in dialysis water and dialysate: occurrence, susceptibility to antifungal agents and biofilm production capacity

The aim of this study was to investigate the occurrence of fungi in dialysis water and dialysate, in addition to evaluating the susceptibility to antifungals and the biofilm production capacity of isolated microorganisms. The samples were collected in three hemodialysis units in Bauru (Brazil), every 15 days (July 2017-June 2018) at post-reverse osmosis, reuse, and dialysate points. The fungi were isolated by spread plate on Sabouraud dextrose agar. Filamentous fungi were phenotypically identified and yeasts were subjected to molecular evaluation of the ITS region. Susceptibility test to antifungals was carried out by the broth microdilution method and biofilm production capacity was evaluated in microtiter plates using crystal violet staining. Fungi were isolated in 52/216 (24.1%) samples, with an average count of 16.3 (10-40) CFU/mL. Overall, 61 microorganisms were identified, with 54 (88.5%) filamentous fungi and 7 (11.5%) yeasts. The main genera included were Penicillium, Cladosporium, Scedosporium, Rhinocladiella, Fusarium, and Emmonsia. Most isolates showed high values of minimum inhibitory concentration for 5-flucytosine and fluconazole and 35/45 (77.8%) isolates were classified as strong producers of biofilm. In order to increase the safety of the dialysis process, the adoption of control measures and monitoring of fungi in hemodialysis fluids is suggested.

A multicenter feasibility randomized controlled trial to assess the impact of incremental versus conventional initiation of hemodialysis on residual kidney function

Twice-weekly hemodialysis, as part of incremental initiation, has reported benefits including preservation of residual kidney function (RKF). To explore this, we initiated a randomized controlled feasibility trial examining 55 incident hemodialysis patients with urea clearance of 3 ml/min/1.73 m² or more across four centers in the United Kingdom randomized to standard or incremental schedules for 12 months. Incremental hemodialysis involved twice-weekly sessions, upwardly adjusting hemodialysis dose as RKF was lost, maintaining total (Dialysis+Renal) Std Kt/V above 2. Standard hemodialysis was thrice weekly for 3.5-4 hours, minimum Dialysis Std Kt/V of 2. Primary outcomes were feasibility parameters and effect size of group differences in rate of loss of RKF at six months. Health care cost impact and patient-reported outcomes were explored. Around one-third of patients met eligibility criteria. Half agreed to randomization; 26 received standard hemodialysis and 29 incremental. At 12 months, 21 incremental patients remained in the study vs 12 in the standard arm with no group differences in the urea clearance slope. Ninety-two percent of incremental and 75% of standard arm patients had a urea clearance of 2 ml/min/1.73 m² or more at six months. Serious adverse events were less frequent in incremental patients (Incidence Rate Ratio 0.47, confidence interval 0.27-0.81). Serum bicarbonate was significantly lower in incremental patients indicating supplementation may be required. There were three deaths in each arm. Blood pressure, extracellular fluid and patient-reported outcomes were similar. There was no signal of benefit of incremental hemodialysis in terms of protection of RKF or Quality of Life score. Median incremental hemodialysis costs were significantly lower compared to standard hemodialysis. Thus, incremental hemodialysis appears safe and cost-saving in incident patients with adequate RKF, justifying a definitive trial.

Exercise programme to improve quality of life for patients with end-stage kidney disease receiving haemodialysis: the PEDAL RCT

BACKGROUND

Whether or not clinically implementable exercise interventions in haemodialysis patients improve quality of life remains unknown.

OBJECTIVES

The PEDAL (PrEscription of intraDialytic exercise to improve quAlity of Life in patients with chronic kidney disease) trial evaluated the clinical effectiveness and cost-effectiveness of a 6-month intradialytic exercise programme on quality of life compared with usual care for haemodialysis patients.

DESIGN

We conducted a prospective, multicentre randomised controlled trial of haemodialysis patients from five haemodialysis centres in the UK and randomly assigned them (1 : 1) using a web-based system to (1) intradialytic exercise training plus usual-care maintenance haemodialysis or (2) usual-care maintenance haemodialysis.

SETTING

The setting was five dialysis units across the UK from 2015 to 2019.

PARTICIPANTS

The participants were adult patients with end-stage kidney disease who had been receiving haemodialysis therapy for > 1 year.

INTERVENTIONS

Participants were randomised to receive usual-care maintenance haemodialysis or usual-care maintenance haemodialysis plus intradialytic exercise training.

MAIN OUTCOME MEASURES

The primary outcome of the study was change in Kidney Disease Quality of Life Short Form, version 1.3, physical component summary score (from baseline to 6 months). Cost-effectiveness was determined using health economic analysis and the EuroQol-5 Dimensions, five-level version. Additional secondary outcomes included quality of life (Kidney Disease Quality of Life Short Form, version 1.3, generic multi-item and burden of kidney disease scales), functional capacity (sit-to-stand 60 and 10-metre Timed Up and Go tests), physiological measures (peak oxygen uptake and arterial stiffness), habitual physical activity levels (measured by the International Physical Activity Questionnaire and Duke Activity Status Index), fear of falling (measured by the Tinetti Falls Efficacy Scale), anthropometric measures (body mass index and waist circumference), clinical measures (including medication use, resting blood pressure, routine biochemistry, hospitalisations) and harms associated with intervention. A nested qualitative study was conducted.

RESULTS

We randomised 379 participants; 335 patients completed baseline assessments and 243 patients (intervention, n = 127; control, n = 116) completed 6-month assessments. The mean difference in change in physical component summary score from baseline to 6 months between the intervention group and control group was 2.4 arbitrary units (95% confidence interval -0.1 to 4.8 arbitrary units; p = 0.055). Participants in the intervention group had poor compliance (49%) and very poor adherence (18%) to the exercise prescription. The cost of delivering the intervention ranged from £463 to £848 per participant per year. The number of participants with harms was similar in the intervention (n = 69) and control (n = 56) groups.

LIMITATIONS

Participants could not be blinded to the intervention; however, outcome assessors were blinded to group allocation.

CONCLUSIONS

On trial completion the primary outcome (Kidney Disease Quality of Life Short Form, version 1.3, physical component summary score) was not statistically improved compared with usual care. The findings suggest that implementation of an intradialytic cycling programme is not an effective intervention to enhance health-related quality of life, as delivered to this cohort of deconditioned patients receiving haemodialysis.

FUTURE WORK

The benefits of longer interventions, including progressive resistance training, should be confirmed even if extradialytic delivery is required. Future studies also need to evaluate whether or not there are subgroups of patients who may benefit from this type of intervention, and whether or not there is scope to optimise the exercise intervention to improve compliance and clinical effectiveness.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN83508514.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 40. See the NIHR Journals Library website for further project information.

From sleep medicine to medicine during sleep-a clinical perspective

Objective. In this perspective paper, we aim to highlight the potential of sleep as an auspicious time for diagnosis, management and therapy of non-sleep-specific pathologies.Approach. Sleep has a profound influence on the physiology of body systems and biological processes. Molecular studies have shown circadian-regulated shifts in protein expression patterns across human tissues, further emphasizing the unique functional, behavioral and pharmacokinetic landscape of sleep. Thus, many pathological processes are also expected to exhibit sleep-specific manifestations. Modern advances in biosensor technologies have enabled remote, non-invasive recording of a growing number of physiologic parameters and biomarkers promoting the detection and study of such processes.Main results. Here, we introduce key clinical studies in selected medical fields, which leveraged novel technologies and the advantageous period of sleep to diagnose, monitor and treat pathologies. Studies demonstrate that sleep is an ideal time frame for the collection of long and clean physiological time series data which can then be analyzed using data-driven algorithms such as deep learning.Significance.This new paradigm proposes opportunities to further harness modern technologies to explore human health and disease during sleep and to advance the development of novel clinical applications - from sleep medicine to medicine during sleep.

Effect of intradialytic exercise on bone profile in hemodialysis patients

Background

Chronic kidney disease increases the risk of fractures and altered bone and mineral metabolism. Exercise training could be a non-pharmacological therapeutic intervention. The aim of this work is to evaluate the effect of intradialytic exercise training on bone markers in hemodialysis (HD) patients.

Results

Forty adult patients on regular HD participated in the study. Twenty of which completed 3 months supervised intradialytic cycling exercise program and 20 served as controls. At baseline, there was no difference between both groups regarding age, sex, physical performance, and laboratory studies performed. After 3 months, the exercise group showed significant improvement in short performance battery test (SPBT) total score (P<0.001) associated with significant decrease in serum parathormone (PTH) (P=0.01) and increase in serum alkaline phosphatase (ALP) and bone specific alkaline phosphatase (BALP) (P<0.05 and P<0.001 respectively). Controls did not show similar change in SPBT or laboratory studies. There was no significant change in serum calcium or phosphorus in both groups. A significant positive correlation was observed between SPBT scores post-exercise and both BALP and ALP levels (r=0.432, P=0.01 and r=0.645, P<0.01 respectively). Also, an inverse relation was observed between SPBT and PTH (r=−0.503, P=0.01).

Conclusion

Intradialytic cycling exercise program resulted in significant increase in physical performance associated with decrease in serum PTH and increase in BALP and ALP in HD patients. This indicates the positive influence of exercise not only on physical performance in dialysis patients but also on bone metabolism.

One-year intradialytic leg exercises with resistance bands and fat mass increase in elderly hemodialysis patients: a retrospective study

Background

Intradialytic exercises are recommended to be available as a treatment for enhancing physical functioning. However, there have been few reports which evaluated the results of long-term mild intradialytic exercises in elderly patients. The purpose of this study is to investigate the changes in body weight, body composition, and laboratory data in elderly hemodialysis patients after 1-year intradialytic leg exercises with resistance bands.

Methods

A retrospective study. Twenty-one outpatients, aged 65 or older (mean ± SD, 75.2 ± 5.1 years), received intradialytic leg exercises with resistance bands for a year were analyzed. The values of dry weight, body composition, and laboratory data were collected from the year-ago period, at baseline and 1 year after baseline. Fat and muscle mass were evaluated by using a multi-frequency bioimpedance device.

Results

Physical performance changed and body weight increased after 1-year resistance band exercises. However, the participants gained fat mass, not muscle mass. Although the changes in biochemical data related to protein intake were equivocal, triglyceride levels increased significantly after 1-year exercises. An elevation in serum creatinine levels was observed, even if solute clearance increased significantly.

Conclusions

One-year intradialytic leg exercises with resistance bands may have a potential clinical benefit for body mass index even in elderly hemodialysis patients. However, optimal dietary modification is needed to achieve a balanced increase of muscle and fat mass. An increase of serum creatinine levels does not always mean muscle mass hypertrophy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41100-021-00341-z.

The role of diabetes mellitus in the effectiveness of intradialytic exercise intervention on patients' muscle function

INTRODUCTION

The purpose of this study is to identify the role of diabetes mellitus in the effectiveness of intradialytic exercise intervention among haemodialysis patients.

METHODS

In this multicentre study 90 dialysed patients were allocated to the experimental (EXG, n=57) or control group (CNG, n=33). In EXG, we included 20 diabetic and 37 non-diabetic patients. In CNG, we enrolled 8 diabetic and 25 non-diabetic patients. EXG underwent a 12-week supervised, progressive, intradialytic resistance training programme, while CNG stayed inactive during dialysis. Baseline, post-interventional and post-follow-up assessments of maximal force during hip extension (HE), hip flexion (HF) and knee extension (KE) contractions were completed in both groups of patients.

RESULTS

HE increased in diabetic and non-diabetic EXG patients (diabetic EXG, change: +14.5N; 95% CI=-5.5 to +34.5; non-diabetic EXG, +18.6N; 95% CI=+3.4 to +33.8) and diabetic CNG patients (change: +17.9N; 95% CI=-9.2 to +44.9). Only non-diabetic CNG patients experienced a decrease in HE (change: -22.8N; 95% CI=-36.9 to -8.7, P<.05).

CONCLUSIONS

Resistance training improved muscle function among dialysis patients regardless of the presence of diabetes mellitus. We found that non-diabetic patients lose their muscle function extensively during inactivity, while diabetic patients retain their muscle function.

Expanded hemodialysis: Is anticoagulation of the dialysis circuit different from online hemodiafiltration and high-flux hemodialysis?

Expanded hemodialysis (HDx) has a high capacity for removing medium and medium-large molecules; however, there are no specific recommendations during HDx for anticoagulation of the dialysis circuit. We aimed to evaluate the differences in the efficacy of anticoagulation procedures using the venous port and 40 mg enoxaparin in HDx compared to high-flux hemodialysis (HF-HD) and postdilution online hemodiafiltration (HDF). We compared anticoagulant activity in 11 patients in HDx, HF-HD, and HDF under similar dialysis conditions. In the 33 dialysis sessions, 40 mg enoxaparin was administered through the venous port, and pre- and postdialysis antifactor Xa activity (aXa) and activated partial thromboplastin time (APTT), postdialysis clotting time of the vascular access, visual clotting score of the dialyzer, and any complications with the extracorporeal circuit or bleeding were registered. APTT postdialysis in HDx was not significantly different from that in HF-HD and HDF. Postdialysis aXa in HDx was not significantly different from that in HF-HD and HDF. We found no significant differences in visual clotting score of the dialyzer. Enoxaparin administered through the venous port was sufficient for anticoagulation within the extracorporeal circuit in HDx, HF-HD, and HDF. There were no differences in postdialysis aXa or APTT, most likely because when low molecular-weight heparin is applied through venous port, lesser enoxaparin concentration reaches the dialyzer. Thus, we conclude that the dose of enoxaparin administered through the venous port should not be adjusted according to dialysis technique.

A Cost-Effective Analysis of the CYCLE-HD Randomized Controlled Trial

Introduction

No formal cost-effectiveness analysis has been performed for programs of cycling exercise during dialysis (intradialytic cycling [IDC]). The objective of this analysis is to determine the effect of a 6-month program of IDC on health care costs.

Methods

This is a retrospective formal cost-effectiveness analysis of adult participants with end-stage kidney disease undertaking in-center maintenance hemodialysis enrolled in the CYCLE-HD trial. Data on hospital utilization, primary care consultations, and prescribed medications were extracted from medical records for the 6 months before, during, and after a 6-month program of thrice-weekly IDC. The cost-effectiveness analysis was conducted from a health care service perspective and included the cost of implementing the IDC intervention. The base-case analyses included a 6-month “within trial” analysis and a 12-month “within and posttrial” analysis considering health care utilization and quality of life (QoL) outcomes.

Results

Data from the base-case within trial analysis, based on 109 participants (n = 56 control subjects and n = 53 IDC subjects) showed a reduction in health care utilization costs between groups, favoring the IDC group, and a 73% chance of IDC being cost-effective compared with control subjects at a willingness to pay of £20,000 and £30,000 per quality-adjusted life year (QALY) gained. When QoL data points were extrapolated forward to 12 months, the probability of IDC being cost-effective was 93% and 94% at £20,000 and £30,000 per QALY gained. Sensitivity analysis broadly confirms these findings.

Conclusion

A 6-month program of IDC is cost-effective and the implementation of these programs nationally should be a priority.

Anemia management for home dialysis including the new US public policy initiative

Patients with end-stage kidney disease (ESKD) requiring kidney replacement therapy are often treated in conventional dialysis centers at substantial cost and patient inconvenience. The recent United States Executive Order on Advancing American Kidney Health, in addition to focusing on ESKD prevention and reforming the kidney transplantation system, focuses on providing financial incentives to promote a shift toward home dialysis. In accordance with this order, a goal was set to have 80% of incident dialysis patients receiving home dialysis or a kidney transplant by 2025. Compared with conventional in-center therapy, home dialysis modalities, including both home hemodialysis and peritoneal dialysis, appear to offer equivalent or improved mortality, clinical outcomes, hospitalization rates, and quality of life in patients with ESKD in addition to greater convenience, flexibility, and cost-effectiveness. Treatment of anemia, a common complication of chronic kidney disease, may be easier to manage at home with a new class of agents, hypoxia-inducible factor-prolyl hydroxylase inhibitors, which are orally administered in contrast to the current standard of care of i.v. iron and/or erythropoiesis-stimulating agents. This review evaluates the clinical, quality-of-life, economic, and social aspects of dialysis modalities in patients with ESKD, including during the coronavirus disease 2019 pandemic; explores new therapeutics for the management of anemia in chronic kidney disease; and highlights how the proposed changes in Advancing American Kidney Health provide an opportunity to improve kidney health in the United States.

Perceptions of exercise benefits and barriers: the influence on physical activity behaviour in individuals undergoing haemodialysis and peritoneal dialysis

Background

Despite growing evidence about the benefits of physical activity and exercise in patients receiving dialysis, physical inactivity is highly prevalent. This may be due to uncertainty and lack of appropriate guidance about exercise, or driven by the relative barriers and benefits that patients perceive. Understanding these perceptions in dialysis patients may inform interventions aimed to increase exercise participation.

Methods

Perceived benefits and barriers to exercise were measured by the ‘Dialysis Patient-perceived Exercise Benefits and Barriers Scale’ (DPEBBS). Self-reported physical activity status was assessed by the ‘General Practice Physical Activity Questionnaire’. Barriers and benefits to exercise were classed as binary variables (i.e. yes and no). Frequency analyses and chi-squared tests were conducted to compare the differences perceived by people on haemodialysis (HD) and peritoneal dialysis (PD). Binominal logistical regression was performed to determine which perceived barriers and benefits had the biggest impact on physical activity status.

Results

One thousand twenty-two HD and 124 PD patients completed the DPEBBS. A greater proportion of HD than PD patients reported ‘reduces body pain’ (P = 0.013), ‘delays decline in body function’ (P = 0.01), and ‘improves quality of life’ (P = 0.033) as benefits of exercise. No differences in barriers were observed. Tiredness was the most reported barrier to exercise. Patients who perceived ‘other comorbidities’ (OR 3.389, P < 0.001) or ‘burden of family’ (OR 3.168, P < 0.001) as barriers were 3 times more likely to be inactive.

Conclusions

Dialysis patients perceive several barriers which may prevent them from engaging in physical activity. Addressing these barriers may be key to increasing participation in physical activity and exercise.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40620-021-01024-y.

Endovascular arteriovenous fistulas- are they the answer we haven't been looking for?

INTRODUCTION

Surgically created arteriovenous fistulas are the accepted gold standard for the establishment of hemodialysis access in patients requiring dialysis. However, primary and maturation failures may limit their usage. Recent advances in endovascular technology have resulted in the creation of devices for endovascular arteriovenous fistula formation. These devices may offer an additional or alternative approach to fistula formation in patients with end-stage kidney disease.

AREAS COVERED

This review describes the limitations of surgical arteriovenous fistulas and the endovascular devices currently available. The review covers initial trial data and subsequent studies examining their use.

EXPERT OPINION

Early results achieved with endovascular fistula formation are encouraging. Current limitations of this technology include anatomic suitability and a high rate of re-interventions required to establish maturity. Greater uptake of the technology will also require a review of long-term outcomes in larger patient cohorts.

Effects of Hemodialysis on Prognosis in Individuals with Comorbid ERSD and ICH: A Retrospective Single-Center Study

OBJECTIVES

End-stage renal disease (ESRD) is one of the most critical risk factors of intracerebral hemorrhage (ICH). We aimed to investigate the effects of maintenance hemodialysis on hematoma volume, edema volume, and prognosis in patients with comorbid ESRD and ICH.

MATERIALS AND METHODS

Patients with comorbid ESRD and ICH were divided into two groups based on whether receiving maintenance hemodialysis. Hematoma and perihemorrhagic edema (PHE) volumes and relative edema ratio after admission were assessed on head computed tomography scans.

RESULTS

During the initial diagnosis, the dialysis group had lower PHE volume (16.41 vs 35.90 mL, P = 0.010), total volume of hematoma and edema (31.58 vs 54.58 mL, P = 0.013), and relative edema ratio (0.57 vs 0.92, P = 0.033) than the non-dialysis group. In addition, the peak PHE volume (36.68 vs 84.30 mL, P < 0.001), peak total volume of hematoma and edema (53.45 vs 127.69 mL, P = 0.011), and peak relative edema ratio (1.12 vs 1.92, P = 0.001) within one week after onset were lower in the dialysis group than in the non-dialysis group. The dialysis group had a higher in-hospital mortality rate than the non-dialysis group (40% vs 10%, P = 0.007). At 1-year follow-up, the two groups had similar 1-year-mortality rates and modified Rankin Scale.

CONCLUSIONS

Hemodialysis can prevent the enlargement of edema and reduce PHE volume shortly after onset. Although dialyzed patients had a higher in-hospital mortality rate, hemodialysis did not affect 1-year survival rate and functional neurologic scales.

Physical Infrastructure and Integrated Governance Structure for Home Hemodialysis

In view of the growing enthusiasm for home dialysis use, new dialysis centers may build or expend their home hemodialysis program in the next few years. This review will discuss the main challenges faced by small and large home hemodialysis programs in terms of physical spaces, human resource, training considerations, and overall governance. We will elaborate on the inclusion of home hemodialysis in the kidney replacement therapy care continuum, with a specific interest for collaboration and transition between peritoneal dialysis and home hemodialysis programs.

Relationship of phase angle and peak torque of knee extensors with the performance in six-minute step test in haemodialysis patients

BACKGROUND

Chronic kidney disease is a systemic disease affecting not only renal function, but also endocrine, cardiovascular, and skeletal muscle systems, with broad impact on functionality. Therefore, the assessment of body composition, peripheral muscle function, and exercise tolerance is also of great importance in this population. In addition, the development of reliable strategies that use feasible tools in clinical practice is of great importance in the functional diagnosis, clinical management and prescription of physical activity.

OBJECTIVE

To assess the relationship between phase angle and peak torque of knee extensors with the performance in six-minute step test of patients with chronic kidney disease undergoing haemodialysis.

METHODS

Observational and cross-sectional study at Haemodialysis Centre of Sírio-Libanês Hospital. The evaluations took place 3 days before the haemodialysis sessions. On the first day, patients underwent anthropometric evaluation and biochemical tests (lactate, urea, creatinine, albumin, ferritin and growth factor similar to insulin type 1 [IGF1]). On the second day, performed electrical bioimpedance and exercise tolerance assessed using the six-minute step test. On the last day, the evaluation of knee extensor muscles strength using isokinetic dynamometry was performed.

RESULTS

Eighteen subjects were included, with a mean age of 62.3 ± 17.6 years. A positive linear correlation was observed between the phase angle, derived from the electrical bioimpedance, and the performance in six-minute step test in these patients. It was also possible to observe a linear correlation between phase angle and IGF1, handgrip strength, peak torque of knee extensors and quality of life questionnaire. The peak torque of knee extensors also presented a linear correlation with IGF1, the performance in six-minute step test and mal-nutrition and inflammation score.

CONCLUSION

Phase angle and peak torque of knee extensors were correlated with the performance in six-minute step test. Therefore, the phase angle seems to be an important marker of reduced peripheral muscle function and exercise tolerance in haemodialysis patients.

The combination of malnutrition-inflammation and functional status limitations is associated with mortality in hemodialysis patients

The identification of malnutrition-inflammation-complex (MIC) and functional status (FS) is key to improving patient experience on hemodialysis (HD). We investigate the association of MIC and FS combinations with mortality in HD patients. We analyzed data from 5630 HD patients from 9 countries in DOPPS phases 4–5 (2009–2015) with a median follow-up of 23 [IQR 11, 31] months. MIC was defined as serum albumin < 3.8 g/dL and serum C-reactive protein > 3 mg/L in Japan and > 10 mg/L elsewhere. FS score was defined as the sum of scores from the Katz Index of Independence in Activities of Daily Living and the Lawton-Brody Instrumental Activities of Daily Living Scale. We investigated the association between combinations of MIC (+/−) and FS (low [< 11]/high [≥ 11]) with death. Compared to the reference group (MIC−/high FS), the adjusted hazard ratios [HR (95% CI)] for all-cause mortality were 1.82 (1.49, 2.21) for MIC−/low FS, 1.57 (1.30, 1.89) for MIC+/high FS, and 3.44 (2.80, 4.23) for MIC+/low FS groups. Similar associations were observed with CVD-related and infection-related mortality. The combination of MIC and low FS is a strong predictor of mortality in HD patients. Identification of MIC and poor FS may direct interventions to lessen adverse clinical outcomes in the HD setting.

Recent advances in treatment of haemodialysis

Haemodialysis remains the most widely used treatment for patients with end-stage renal disease. Despite the progress that has occurred in the treatment of end-stage renal disease over the last six decades, there has been a failure to translate this into the desired clinical benefits, with morbidity and mortality rates among patients on haemodialysis remaining unacceptably high. Recently, however, there have been expectations that the significant advances that took place over the last few years may result in improved outcomes. New medications for the treatment of anaemia and secondary hyperparathyroidism, as well as novel trends in the areas of iron therapy, diabetes management and physical exercise are among the most important advances which, taken together, are changing the standards of care for patients on haemodialysis. The latest advances, of relevance not only to specialists in Renal Medicine but also to general practitioners caring for these patients, are reviewed in this collaborative paper.

Comparison of dialysis dose through real-time Kt/V by ultraviolet absorbance of spent dialysate, single-pool Daugirdas II, and Kt/BSA according to sex and age

BACKGROUND

Kt/V OnLine (Kt/VOL) avoids inaccuracies associated with the estimation of urea volume distribution (V). The study aimed to compare Kt/VOL, Kt/V Daugirdas II, and Kt/BSA according to sex and age.

METHODS

Urea volume distribution and body surface area were obtained by Watson and Haycock formulas in 47 patients. V/BSA was considered as a conversion factor from Kt/V to Kt/BSA. Dry weight was determined before the study. Kt/VOL was obtained on DIALOG machines.

RESULTS

Pearson correlation between Kt/VOL vs Kt/VII and Kt/VOL vs Kt/BSA was significant for males (r = 0.446, P = 0.012 and r = -0.476 P = 0.007) and individuals < 65 years (0.457, P = 0.019 and -0.549 P = 0.004), but not for females and individuals ≥ 65 years. V/BSA between individuals < 65 and individuals ≥ 65 years were 18.28 ± 0.15 and 18.18 ± 0.16 P = 0.000). No agreement between Kt/VII vs Kt/BSA. Men and individuals > 65 years received a larger dialysis dose than, respectively, females and individuals < 65 years, in the comparison between Kt/VOL versus Kt/VII. V/BSA ratios among men and women were respectively 18.29 ± 0.13 and 18.12 ± 0.15 P = 0.000.

CONCLUSIONS

Kt/VOL allows recognition of real-time dose regardless of sex and age.

Safely reducing haemodialysis frequency during the COVID-19 pandemic

BACKGROUND

Patients undergoing haemodialysis (HD) are at higher risk of developing worse outcomes if they contract COVID-19. In our renal service we reduced HD frequency from thrice to twice-weekly in selected patients with the primary aim of reducing COVID 19 exposure and transmission between HD patients.

METHODS

Dialysis unit nephrologists identified 166 suitable patients (38.4% of our HD population) to temporarily convert to twice-weekly haemodialysis immediately prior to the peak of the COVID-19 pandemic in our area. Changes in pre-dialysis weight, systolic blood pressure (SBP) and biochemistry were recorded weekly throughout the 4-week project. Hyperkalaemic patients (serum potassium > 6.0 mmol/L) were treated with a potassium binder, sodium bicarbonate and received responsive dietary advice.

RESULTS

There were 12 deaths (5 due to COVID-19) in the HD population, 6 of which were in the twice weekly HD group; no deaths were definitively associated with change of dialysis protocol. A further 19 patients were either hospitalised and/or developed COVID-19 and thus transferred back to thrice weekly dialysis as per protocol. 113 (68.1%) were still receiving twice-weekly HD by the end of the 4-week project. Indications for transfer back to thrice weekly were; fluid overload (19), persistent hyperkalaemia (4), patient request (4) and compliance (1). There were statistically significant increases in SBP and pre-dialysis potassium during the project.

CONCLUSIONS

Short term conversion of a large but selected HD population to twice-weekly dialysis sessions was possible and safe. This approach could help mitigate COVID-19 transmission amongst dialysis patients in centres with similar organisational pressures.

Prevalence of Erectile Dysfunction in Patients With End-Stage Renal Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Erectile dysfunction (ED) is an under-recognized clinical entity in men with end-stage renal disease (ESRD), and studies on renal transplant recipients, patients on dialysis, and patients starting dialysis report different prevalence rates and severity of ED among these groups.

AIM

To determine the prevalence and severity of ED in patients with ESRD, assessed with the International Index of Erectile Function-15 and International Index of Erectile Function-5.

METHODS

We performed a systematic review and meta-analysis of observational studies assessing the prevalence of ED in ESRD individuals. (PROSPERO ID: CRD42020182680). Records were identified by search in MEDLINE, Scopus, and CENTRAL databases and sources of gray literature until July 2020. We conducted a random-effects meta-analysis of proportions (double arcsine transformation).

OUTCOMES

We included 94 studies with 110 patient group entries and a total of 10,320 ESRD male individuals with a mean age of 48.8 ± 14.25 years.

RESULTS

Overall, 7,253 patients experienced ED. We estimated an overall pooled ED prevalence of 71% (95% CI: 67-74%, I² = 92%). In the subgroup analyses, the pooled prevalence was 59% (95% CI: 53-64%, I² = 92%) among renal transplant recipients, 79% (95% CI: 75-82%, I² = 86%) in patients on hemodialysis, 71% (95% CI: 58-83%, I² = 86%) in patients on peritoneal dialysis, and 82% (95% CI: 75-88%, I² = 0%) in patients with ESRD starting dialysis. The prevalence of the severity of ED was also estimated. Further assessment of heterogeneity was conducted via sensitivity analysis, cumulative meta-analysis, and meta-regression of significant risk factors.

CLINICAL TRANSLATION

Despite its high prevalence in patients with ESRD, ED constitutes an underestimated and taboo subject in this group. Therefore, arousing clinical concern among healthcare providers involved in ESRD management is more than necessary to screen and treat ED in patients receiving renal replacement therapy.

STRENGTHS & LIMITATIONS

We estimated ED solely for ESRD, included the largest number of patients compared with previous studies and estimated ED prevalence as per severity and renal replacement therapy subgroups. Contrary, because we restricted our eligibility criteria to the International Index of Erectile Function, some studies assessing ED prevalence with other validated tools were not included in this meta-analysis. Moreover, the levels of heterogeneity among studies remained high after sensitivity and meta-regression analyses, and for some moderators, the results of the meta-regression might have been underpowered.

CONCLUSIONS

ED is highly prevalent in patients with ESRD irrespective of the type of renal replacement therapy, thereby warranting clinical attention. Pyrgidis N, Mykoniatis I, Nigdelis MP, et al. Prevalence of Erectile Dysfunction in Patients With End-Stage Renal Disease: A Systematic Review and Meta-Analysis. J Sex Med 2021;18:113-120.

Anticoagulation in hemodialysis: A narrative review

Systemic anticoagulation in maintenance hemodialysis (HD) has historically been considered necessary to maintain the extracorporeal circuit (ECC) and preserve dialysis efficiency. Unfractionated heparin (UFH) is the most commonly used anticoagulant due to low cost and staff familiarity. Despite widespread use, there is little standardization of heparin dosing protocols in the United States. Although the complication rates with UFH are low for the general population, certain contraindications have led to exploration in alternative anticoagulants in patients with end-stage kidney disease (ESKD). Here we review the current evidence regarding heparin dosing protocols, complications associated with heparin use, and discuss alternatives to UFH including anticoagulant-free routine HD.

Anticoagulation strategies in extracorporeal circulatory devices in adult populations

Extracorporeal circulatory devices such as hemodialysis and extracorporeal membrane oxygenation can be lifesaving; however, they are also prone to pathologic events including device failure, venous and arterial thrombosis, hemorrhage, and an accelerated risk for atherosclerotic disease due to interactions between blood components and device surfaces of varying biocompatibility. While extracorporeal devices may be used acutely for limited periods of time (eg, extracorporeal membrane oxygenation, continuous venovenous hemofiltration, therapeutic apheresis), some patients require chronic use of these technologies (eg, intermittent hemodialysis and left ventricular assist devices). Given the substantial thrombotic risks associated with extracorporeal devices, multiple antiplatelet and anticoagulation strategies-including unfractionated heparin, low-molecular-weight heparin, citrate, direct thrombin inhibitors, and direct oral anticoagulants, have been used to mitigate the thrombotic milieu within the patient and device. In the following manuscript, we outline the current data on anticoagulation strategies for commonly used extracorporeal circulatory devices, highlighting the potential benefits and complications involved with each.

The PrEscription of intraDialytic exercise to improve quAlity of Life in patients with chronic kidney disease trial: study design and baseline data for a multicentre randomized controlled trial

Background

Exercise interventions designed to improve physical function and reduce sedentary behaviour in haemodialysis (HD) patients might improve exercise capacity, reduce fatigue and lead to improved quality of life (QOL). The PrEscription of intraDialytic exercise to improve quAlity of Life study aimed to evaluate the effectiveness of a 6-month intradialytic exercise programme on QOL and physical function, compared with usual care for patients on HD in the UK.

Methods

We conducted a prospective, pragmatic multicentre randomized controlled trial in 335 HD patients and randomly (1:1) assigned them to either (i) intradialytic exercise training plus usual care maintenance HD or (ii) usual care maintenance HD. The primary outcome of the study was the change in Kidney Disease Quality of Life Short Form (KDQOL-SF 1.3) Physical Component Score between baseline and 6 months. Additional secondary outcomes included changes in peak aerobic capacity, physical fitness, habitual physical activity levels and falls (International Physical Activity Questionnaire, Duke’s Activity Status Index and Tinetti Falls Efficacy Scale), QOL and symptom burden assessments (EQ5D), arterial stiffness (pulse wave velocity), anthropometric measures, resting blood pressure, clinical chemistry, safety and harms associated with the intervention, hospitalizations and cost-effectiveness. A nested qualitative study investigated the experience and acceptability of the intervention for both participants and members of the renal health care team.

Results

At baseline assessment, 62.4% of the randomized cohort were male, the median age was 59.3 years and 50.4% were white. Prior cerebrovascular events and myocardial infarction were present in 8 and 12% of the cohort, respectively, 77.9% of patients had hypertension and 39.4% had diabetes. Baseline clinical characteristics and laboratory data for the randomized cohort were generally concordant with data from the UK Renal Registry.

Conclusion

The results from this study will address a significant knowledge gap in the prescription of exercise interventions for patients receiving maintenance HD therapy and inform the development of intradialytic exercise programmes both nationally and internationally.

Trial Registration

ISRCTN N83508514; registered on 17 December 2014.

Efficacy of enoxaparin in preventing coagulation during high-flux haemodialysis, expanded haemodialysis and haemodiafiltration

Background

Low-molecular-weight heparins (LMWHs) are easily dialysable with high-flow membranes; however, it is not clear whether the LMWH dose should be adjusted according to the membrane type and dialysis technique. This study aimed to evaluate the influence of the dialyser on anticoagulation of the extracorporeal dialysis circuit.

Methods

Thirteen patients received the same dose of LMWH through the arterial port via three dialysis techniques: high-flux haemodialysis (HF-HD), online haemodiafiltration (HDF) and expanded haemodialysis (HDx). All dialysis was performed under similar conditions: duration, 4 h; blood flow, 400 mL/min; and dialysate flow, 500 mL/min. Antifactor Xa (aXa) activity and activated partial thromboplastin time (APTT) were measured before and after the dialysis. Clotting time of the vascular access site after haemodialysis, visual clotting score of the dialyser and any complications with the extracorporeal circuit or bleeding were registered.

Results

Post-dialysis aXa activity in HF-HD (0.26 ± 0.02 U/mL) was significantly different from that in HDF (0.21 ± 0.02 U/mL, P = 0.024), and there was a trend in HDx (0.22 ± 0.01 U/mL, P = 0.05). APTT post-dialysis in HF-HD (30.5 ± 0.7 s) was significantly different from that in HDx (28.2 ± 0.64 s, P = 0.009) and HDF (28.8 ± 0.73 s, P = 0.009).

Conclusions

AXa activity in HDF was significantly lower than that in HF-HD, possibly because of more losses of LMWH through the dialyser. Given the higher anticoagulant loss in HDF and probably in HDx than in HF-HD, the enoxaparin dose administered may be adjusted according to the dialysis technique.

Exercise in patients on chronic hemodialysis: current evidence, knowledge gaps and future perspectives

PURPOSE OF REVIEW

Physical inactivity is common in hemodialysis patients, and is associated with disability and poor outcomes. We summarize the effects of aerobic, resistance or mixed exercise training on aerobic capacity, muscle mass and strength, dialysis efficiency, quality of life and cardiovascular adaptation according to clinical studies on this population, also focusing on knowledge gaps as topics for future research. Finally, we put evidence into clinical context deriving practical indications for exercise implementation in these patients.

RECENT FINDINGS

In hemodialysis patients, aerobic or mixed exercise training increases predominantly aerobic capacity, whereas resistance training seems more effective in increasing muscle strength. Data concerning dialysis efficiency are equivocal, although phosphate and potassium clearances seem to be improved. There is also inconclusive evidence concerning changes in cardiovascular risk factors. All types of exercise improve patients' quality of life. However, there is a need for protocol standardization and selection of easily measurable endpoints. In clinical practice, it is advised that exercise implementation be performed gradually, and goals be tailored to individual pretraining fitness levels to maximize patient adherence and clinical benefits.

SUMMARY

The overall evidence suggests that exercise training is beneficial and well tolerated in hemodialysis patients, although heterogeneity across studies hinders generalization of results. In any case, a gradual and individualized approach should be used to implement exercise in these patients.

Applications of Near Infrared Photoacoustic Spectroscopy for Analysis of Human Respiration: A Review

In this review, applications of near-infrared photoacoustic spectroscopy are presented as an opportunity to evaluate human respiration because the measurement of breath is fast, intact and simple to implement. Recently, analytical methods for measuring biomarkers in exhaled air have been extensively developed. With laser-based photoacoustic spectroscopy, volatile organic compounds can be identified with high sensitivity, at a high rate, and with very good selectivity. The literature review has shown the applicability of near-infrared photoacoustic spectroscopy to one of the problems of the real world, i.e., human health. In addition, the review will consider and explore different breath sampling methods for human respiration analysis.

Major Outcomes With Personalized Dialysate TEMPerature (MyTEMP): Rationale and Design of a Pragmatic, Registry-Based, Cluster Randomized Controlled Trial

BACKGROUND

Small randomized trials demonstrated that a lower compared with higher dialysate temperature reduced the average drop in intradialytic blood pressure. Some observational studies demonstrated that a lower compared with higher dialysate temperature was associated with a lower risk of all-cause mortality and cardiovascular mortality. There is now the need for a large randomized trial that compares the effect of a low vs high dialysate temperature on major cardiovascular outcomes.

OBJECTIVE

The purpose of this study is to test the effect of outpatient hemodialysis centers randomized to (1) a personalized temperature-reduced dialysate protocol or (2) a standard-temperature dialysate protocol for 4 years on cardiovascular-related death and hospitalizations.

DESIGN

The design of the study is a pragmatic, registry-based, open-label, cluster randomized controlled trial.

SETTING

Hemodialysis centers in Ontario, Canada, were randomized on February 1, 2017, for a trial start date of April 3, 2017, and end date of March 31, 2021.

PARTICIPANTS

In total, 84 hemodialysis centers will care for approximately 15 500 patients and provide over 4 million dialysis sessions over a 4-year follow-up.

INTERVENTION

Hemodialysis centers were randomized (1:1) to provide (1) a personalized temperature-reduced dialysate protocol or (2) a standard-temperature dialysate protocol of 36.5°C. For the personalized protocol, nurses set the dialysate temperature between 0.5°C and 0.9°C below the patient's predialysis body temperature for each dialysis session, to a minimum dialysate temperature of 35.5°C.

PRIMARY OUTCOME

A composite of cardiovascular-related death or major cardiovascular-related hospitalization (a hospital admission with myocardial infarction, congestive heart failure, or ischemic stroke) captured in Ontario health care administrative databases.

PLANNED PRIMARY ANALYSIS

The primary analysis will follow an intent-to-treat approach. The hazard ratio of time-to-first event will be estimated from a Cox model. Within-center correlation will be considered using a robust sandwich estimator. Observation time will be censored on the trial end date or when patients die from a noncardiovascular event.

TRIAL REGISTRATION

www.clinicaltrials.gov; identifier: NCT02628366.

Dietary Protein and Physical Activity Interventions to Support Muscle Maintenance in End-Stage Renal Disease Patients on Hemodialysis

End-stage renal disease patients have insufficient renal clearance capacity left to adequately excrete metabolic waste products. Hemodialysis (HD) is often employed to partially replace renal clearance in these patients. However, skeletal muscle mass and strength start to decline at an accelerated rate after initiation of chronic HD therapy. An essential anabolic stimulus to allow muscle maintenance is dietary protein ingestion. Chronic HD patients generally fail to achieve recommended protein intake levels, in particular on dialysis days. Besides a low protein intake on dialysis days, the protein equivalent of a meal is extracted from the circulation during HD. Apart from protein ingestion, physical activity is essential to allow muscle maintenance. Unfortunately, most chronic HD patients have a sedentary lifestyle. Yet, physical activity and nutritional interventions to support muscle maintenance are generally not implemented in routine patient care. To support muscle maintenance in chronic HD patients, quantity and timing of protein intake should be optimized, in particular throughout dialysis days. Furthermore, implementing physical activity either during or between HD sessions may improve the muscle protein synthetic response to protein ingestion. A well-orchestrated combination of physical activity and nutritional interventions will be instrumental to preserve muscle mass in chronic HD patients.