Hemodiafiltration outcomes in special situations.

This Seminars in Dialysis Hemodiafiltration Symposium includes many references regarding the outcomes of this modality in general. The results in special populations are included in some of the studies, but have not been compared in a systematic manner. The purpose of this review is to compile those outcome results in select populations.

On-line hemodiafiltration therapy for end-stage kidney disease patients: Promises for the future? What's next?

On-line hemodiafiltration (OL-HDF) is currently the most advanced form of blood purification modality leading convective-based therapies in end-stage kidney disease patients. By adding a high convective component to the diffusive clearance achieved with highly permeable dialyzers, OL-HDF reinforces removal of small MWt compounds and enlarges the spectrum of uremic compounds cleared up to middle and large MWt compounds. The biological and clinical benefits of convective-based therapy are currently also being explored in a revisited hybrid modality, combining an increased internal filtration process with a more open membrane. Regular use of ultrapure dialysis fluid required by convective-based therapies improves the bio-incompatibility of the extracorporeal circuit so reducing inflammatory responses. On-line production of substitution fluid, relying on a cold sterilization by ultrafiltration, has several advantages: First, it is a safe and established process; and second, it provides an unlimited amount of substitution fluid at the same cost as regular ultrapure dialysis fluid. As such, OL-HDF is adaptable to all substitution modalities (post, pre, or mixed-HDF), thus allowing the dialytic convective dose to be adjusted to the individual patient needs. The development of OL-HDF opens new pathways such as task automation simplifying care workflow. All these features make OL-HDF the most versatile dialysis modality that can be now integrated in various treatment schedules according to session time and frequency (daily, nocturnal, or alternate day) or location (incenter, satellite, or potentially home-based therapy).

Exploring Barriers and Potential Solutions in Home Dialysis: An NKF-KDOQI Conference Outcomes Report.

Home dialysis therapy, including home hemodialysis and peritoneal dialysis, is underused as a modality for the treatment of chronic kidney failure. The National Kidney Foundation-Kidney Disease Outcomes Quality Initiative sponsored a home dialysis conference in late 2017 that was designed to identify the barriers to starting and maintaining patients on home dialysis therapy. Clinical, operational, policy, and societal barriers were identified that need to be overcome to ensure that dialysis patients have the freedom to choose their treatment modality. Education of patients and patient partners, as well as health care providers, about home dialysis therapy, if offered at all, is often provided in a cursory manner. Lack of exposure to home dialysis therapies perpetuates a lack of familiarity and thus a hesitancy to refer patients to home dialysis therapies. Patient and care partner support, both psychosocial and financial, is also critical to minimize the risk for burnout leading to dropout from a home dialysis modality. Thus, the facilitation of home dialysis therapy will require a systematic change in chronic kidney disease education and the approach to dialysis therapy initiation, the creation of additional incentives for performing home dialysis, and breakthroughs to simplify the performance of home dialysis modalities. The home dialysis work group plans to develop strategies to overcome these barriers to home dialysis therapy, which will be presented at a follow-up home dialysis conference.

Incremental dialysis: review of recent literature.

PURPOSE OF REVIEW: There are clinical, physiological, financial, and practical reasons to perform incremental hemodialysis in selected patients, incident to end-stage renal disease. Recent papers inform us further, especially in the large database studies. RECENT FINDINGS: Small studies suggested, then a larger study corroborated, that incremental hemodialysis was associated with preservation of residual kidney function whenever compared with conventional hemodialysis. The well tolerated nutritional status of incremental hemodialysis was questioned in a small study but a larger study was more reassuring. The mortality rate of patients undergoing incremental hemodialysis is similar to that in conventional hemodialysis, but only if the comorbidity burden is low. SUMMARY: Incremental hemodialysis in incident patients can be performed safely, and probably is associated with preserved residual kidney function and a similar mortality rate to convention initiation of hemodialysis. Patients must be prudently selected and managed for this approach to the initiation of dialysis.

Incremental Hemodialysis: How I Do It.

Incremental hemodialysis (incrHD) is not widely used nor is it well understood. In addition, and perhaps with more impact, governmental regulations in the United States and their consequential influences on dialysis provider organizations have made the practice of incrHD more difficult than traditional thrice weekly in-center HD. IncrHD is critically dependent on the amount of residual kidney function (RKF) as well as the individualized goals of end-stage renal disease (ESRD) management. RKF has to be assessed frequently and dialysis adjusted accordingly. Home HD lends itself to an incremental approach more so than in-center HD. This may be due to more experience of the provider, more knowledge of the therapy by the patient and family, the availability of dialysis platforms conducive to incrHD, and/or that its less onerous regulation by the government. I have had a long and successful experience performing incremental dialysis (both peritoneal and hemodialysis) and share here my practice strategies and approaches for incrHD.

Is hemodiafiltration ready for broader use?

Hemodiafiltration is practiced throughout Europe and in a few additional countries but, because of regulatory restrictions, is not currently available in the United States. Hemodiafiltration removes uremic species more broadly than is achieved by diffusion dialysis, perhaps explaining its better outcome profile.

Arteriovenous fistula creation may slow estimated glomerular filtration rate trajectory.

BACKGROUND: We practice the timely placement of an arteriovenous fistula (AVF) in patients facing chronic hemodialysis. We have anecdotally observed after AVF creation that there appears to be a slowing of the decline in kidney function as measured by the estimated glomerular filtration rate (eGFR). There are physiologically plausible explanations as to how an AVF might alter kidney function, but this clinical observation has been attributed to improved compliance and/or other practices. The present retrospective observational analysis was performed to assess the possibility that a successfully created AVF could be associated with the slowing of the eGFR trajectory. METHODS: We identified 123 patients between 2005 and 2010 with at least two eGFR determinations for 2 years before and up to 2 years after AVF creation. Inclusion eligibility was that the fistula was maturing by the nephrologists' initial post-creation examination. Termination events were death, starting dialysis or transplantation. Each subject served as their own control for the pre- and post-AVF-creation eGFR measurements. RESULTS: Subjects' median age was 68 years and 56% were diabetic. The rate of change of the eGFR for the 2 years prior to AVF creation was -5.9 mL/min/year (95% CI: -5.3, -6.5) and after AVF creation -0.5 mL/min/year (95% CI: -1.1, 0.1) (interaction (P < 0.001). CONCLUSIONS: A functioning AVF may be associated with a slowing of the eGFR decline. Agreeing to timely AVF creation selects patients in an otherwise typical population and other confounders have not yet been eliminated. To do so a thorough prospective observational study is indicated.

Comparative outcomes between continuous ambulatory and automated peritoneal dialysis: a narrative review.

Automated methods for delivering peritoneal dialysis (PD) to persons with end-stage renal disease continue to gain popularity worldwide, particularly in developed countries. However, the endeavor to automate the PD process has not been advanced on the strength of high-level evidence for superiority of automated over manual methods. This article summarizes available studies that have shed light on the evidence that compares the association of treatment with continuous ambulatory PD or automated PD (APD) with clinically meaningful outcomes. Published evidence, primarily from observational studies, has been unable to demonstrate a consistent difference in residual kidney function loss rate, peritonitis rate, maintenance of euvolemia, technique survival, mortality, or health-related quality of life in individuals undergoing continuous ambulatory PD versus APD. At the same time, the future of APD technology appears ripe for further improvement, such as the incorporation of voice commands and expanded use of telemedicine. Given these considerations, it appears that patient choice should drive the decision about PD modality.

Amino acid losses during sustained low efficiency dialysis in critically ill patients with acute kidney injury.

OBJECTIVE: Sustained low efficiency dialysis (SLED) involves the use of standard dialysis machines for prolonged intermittent renal replacement therapy in critically ill patients. In this study we aimed to quantify dialysate amino acid (AA) and albumin losses in 5 patients who underwent successful SLED treatment. DESIGN: This was a prospective observational study. SETTING: The study was performed in a general intensive care unit. SUBJECTS: The study was performed in critically ill patients with acute kidney injury undergoing SLED using low-flux hemodialyzers. INTERVENTION: We performed total dialysate collection and measured dialysate AA profiles by reverse phase high-pressure liquid chromatography using an automated AA analyser. MAIN OUTCOME MEASURE: Individual and total amino acid losses. RESULTS: Albumin was undetectable in dialysate. The median (mean ± SD) total amino acid loss was 15.7 (23.4 ± 19.2) g/treatment, or 122.1 (180.6 ± 148.5) mmol/treatment. Two patients were receiving intravenous nutrition. One patient had severe hepatic failure with encephalopathy, and had high dialysate AA levels with a total loss of 57 g/treatment. CONCLUSIONS: During SLED with low-flux hemodialyzers, albumin losses are negligible but AA losses to dialysate are comparable to those during continuous renal replacement therapy. Patients' nutritional protein prescriptions should be augmented to account for this.

Ultrafiltration Patterns during Automated Peritoneal Dialysis: Findings and Insights to Peritoneal Physiology.

BACKGROUND: With the growing use of automated peritoneal dialysis (APD), it is important to improve our knowledge of the clinical patterns and physiology of APD treatment sessions. The ultrafiltration (UF) achieved during each cycle of an APD treatment is assumed to be relatively linear if the delivered prescription is the same. We set out to determine if that is indeed the case. METHODS: Single-center, cross-sectional study of prevalent PD patients. All adult APD patients (> 18 years of age), who had been on PD for >3 months, and >3 months on APD were included. Continuous ambulatory PD patients or those with peritonitis within 3 months of the consent date were excluded. Individual treatment data from 7 consecutive APD treatment sessions with consistent dialysate composition for each cycler exchange were collected for each subject. RESULTS: Thirty-nine subjects met the inclusion criteria and were enrolled. The probability of yielding a positive UF was 48.9% for cycle 1, rising to 90.5% by cycle 6. Adjusting for average dextrose concentration, dwell time, fill volume, solute transfer rate, and number of cycles, we observed that cycles 2 through 6 achieved progressively higher UF volumes than cycle 1 (p < 0.001). The first and last cycles demonstrated significantly different cycle UF volumes compared to a middle cycle (-230 ml and 277 ml, respectively, p < 0.001). CONCLUSIONS: We observed a consistent increase in UF volumes achieved per cycle over the course of an APD treatment session with numerous clinical and physiologic implications. This provides the foundation for future studies investigating peritoneal inter-cycle variations and membrane physiology.

Is Dorothy correct? The role of patient education in promoting home dialysis.

The major payer of dialysis services in the United States, Medicare, has established incentives to encourage the use of home dialysis. However, this modality remains underutilized. We think that a major cause of this situation is ineffective education of the prospective dialysis population regarding the choices of kidney replacement modalities. We discuss the value of patient education and the consequences of failing to educate prospective dialysis patients. We then explore approaches to achieve patient education goals and the physician's and education team's roles in the development of an individual patient's life plan.

Systematic barriers to the effective delivery of home dialysis in the United States: a report from the Public Policy/Advocacy Committee of the North American Chapter of the International Society for Peritoneal Dialysis.

Home dialysis, currently underused in the United States compared with other industrialized countries, likely will benefit from the newly implemented US prospective payment system. Not only is home dialysis less expensive from the standpoint of pure dialysis costs, but overall health system costs may be decreased by more subtle benefits, such as reduced transportation. However, many systematic barriers exist to the successful delivery of home dialysis. We organized these barriers into the categories of educational barriers (patient and providers), governmental/regulatory barriers (state and federal), and barriers specifically related to the philosophies and business practices of dialysis providers (eg, staffing, pharmacies, supplies, space, continuous quality improvement practices, and independence). All stakeholders share the goal of delivering home dialysis therapies in the most cost- and clinically effective and least problematic manner. Identification and recognition of such barriers is the first step. In addition, we have suggested action plans to stimulate the kidney community to find even better solutions so that collectively we may overcome these barriers.

C.E.R.A. once every 4 weeks corrects anaemia and maintains haemoglobin in patients with chronic kidney disease not on dialysis.

BACKGROUND: No previous randomized controlled studies have been reported examining de novo, once every 4 weeks (Q4W) administration of erythropoiesis-stimulating agents in chronic kidney disease (CKD) patients. We report results from a randomized multinational study that compared continuous erythropoietin receptor activator (C.E.R.A.) Q4W with darbepoetin alfa once weekly (QW) or every 2 weeks (Q2W) for the correction of anaemia in non-dialysis CKD patients. METHODS: Patients were randomized (1:1) to receive either 1.2 µg/kg C.E.R.A. Q4W or darbepoetin alfa QW/Q2W during a 20-week correction period and an 8-week evaluation period. Two primary end points were assessed: the haemoglobin (Hb) response rate and the change in average Hb concentration between baseline and evaluation. RESULTS: The Hb response rate for C.E.R.A. was 94.1%, significantly higher than the protocol-specified 60% response rate [95% confidence interval (CI): 89.1, 97.3; P < 0.0001] and comparable with darbepoetin alfa (93.5%; 95% CI: 88.4, 96.8; P < 0.0001). C.E.R.A. Q4W was non-inferior to darbepoetin alfa QW/Q2W, with similar mean Hb changes from baseline of 1.62 g/dL and 1.66 g/dL, respectively. Patients receiving C.E.R.A. showed a steady rise in Hb, with fewer patients above the target range during the first 8 weeks compared with darbepoetin alfa [39 patients (25.8%) versus 72 patients (47.7%); P < 0.0001]. Adverse event rates were comparable between the treatment groups. CONCLUSION: C.E.R.A. Q4W successfully corrects anaemia and maintains stable Hb levels within the recommended target range in non-dialysis CKD patients.

Low-efficiency acute renal replacement therapy: role in acute kidney injury.

The methodology, prescription, and delivery of acute renal replacement therapy are rapidly evolving areas. Recent clinical trials have provided clearer guidance around dosing targets for both therapy prescription and delivery. In this article, we discuss dialysis efficiency which is an area that subserves dialysis dose and pertains to manner in which a given dose is delivered. Dialysis efficiency directly effects the measurement and calculation of dose, and the occurrence of dialysis disequilibrium and hemodynamic instability. We provide recommendations around selecting the most appropriate clinical scenario and patients for higher-efficiency versus lower-efficiency therapy, and the implementation of therapy to achieve a given efficiency.

Prescribing Home Hemodialysis.

Home hemodialysis (HHD), performed more frequently than in-center hemodialysis, is underutilized in the United States but has had a recent resurgence driven predominantly by innovative dialysis equipment that is easy to use, less intrusive to the home, and requires less storage space. There are 3 different hemodialysis machines approved for use in the home but currently NxStage™ accounts for the overwhelming majority of HHD patients. Therefore, it is the focus of this article. To minimize storage space in the home, the NxStage platform minimizes the volume of dialysate that is used per treatment. We refer to this method as the Frequent Low Dialysate Volume Approach (FLDVA). The approach to urea removal with the NxStage platform is much different compared to traditional in-center HD. To minimize the volume of dialysate per treatment, and still achieve target urea removal, the dialysate must be highly saturated. In this article, we explain how to increase the saturation of dialysate fluid. We also draw a parallel between urea removal in peritoneal dialysis and NxStage therapy and use that model to estimate an initial HHD prescription and to alter prescriptions when necessary.

Nomenclature in nephrology: preserving 'renal' and 'nephro' in the glossary of kidney health and disease.

A recently published nomenclature by a "Kidney Disease Improving Global Outcomes" (KDIGO) Consensus Conference suggested that the word "kidney" should be used in medical writings instead of "renal" or "nephro" when referring to kidney disease and kidney health. Whereas the decade-old move to use "kidney" more frequently should be supported when communicating with the public-at-large, such as the World Kidney Day, or in English speaking countries in communications with patients, care-partners, and non-medical persons, our point of view is that "renal" or "nephro" should not be removed from scientific and technical writings. Instead, the terms can coexist and be used in their relevant contexts. Cardiologists use "heart" and "cardio" as appropriate such as "heart failure" and "cardiac care units" and have not replaced "cardiovascular" with "heartvessel", for instance. Likewise, in nephrology, we consider that "chronic kidney disease" and "continuous renal replacement therapy" should coexist. We suggest that in scientific writings and technical communications, the words "renal" and "nephro" and their derivatives are more appropriate and should be freely used without any pressure by medical journals to compel patients, care-partners, healthcare providers, researchers and other stakeholders to change their selected words and terminologies. We call to embrace the terms "kidney", "renal" and "nephro" as they are used in different contexts and ask that scientific and medical journals not impose terminology restrictions for kidney disease and kidney health. The choice should be at the discretion of the authors, in the different contexts including in scientific journals.