Safety and efficacy of the Tablo hemodialysis system for in-center and home hemodialysis

Home versus in-centre haemodialysis for people with kidney failure

BACKGROUND

Home haemodialysis (HHD) may be associated with important clinical, social or economic benefits. However, few randomised controlled trials (RCTs) have evaluated HHD versus in-centre HD (ICHD). The relative benefits and harms of these two HD modalities are uncertain. This is an update of a review first published in 2014. This update includes non-randomised studies of interventions (NRSIs).

OBJECTIVES

To evaluate the benefits and harms of HHD versus ICHD in adults with kidney failure.

SEARCH METHODS

We contacted the Information Specialist and searched the Cochrane Kidney and Transplant Register of Studies up to 9 October 2022 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov. We searched MEDLINE (OVID) and EMBASE (OVID) for NRSIs.

SELECTION CRITERIA

RCTs and NRSIs evaluating HHD (including community houses and self-care) compared to ICHD in adults with kidney failure were eligible. The outcomes of interest were cardiovascular death, all-cause death, non-fatal myocardial infarction, non-fatal stroke, all-cause hospitalisation, vascular access interventions, central venous catheter insertion/exchange, vascular access infection, parathyroidectomy, wait-listing for a kidney transplant, receipt of a kidney transplant, quality of life (QoL), symptoms related to dialysis therapy, fatigue, recovery time, cost-effectiveness, blood pressure, and left ventricular mass.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed if the studies were eligible and then extracted data. The risk of bias was assessed, and relevant outcomes were extracted. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) or standardised mean difference (SMD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Meta-analysis was performed on outcomes where there was sufficient data.

MAIN RESULTS

From the 1305 records identified, a single cross-over RCT and 39 NRSIs proved eligible for inclusion. These studies were of varying design (prospective cohort, retrospective cohort, cross-sectional) and involved a widely variable number of participants (small single-centre studies to international registry analyses). Studies also varied in the treatment prescription and delivery (e.g. treatment duration, frequency, dialysis machine parameters) and participant characteristics (e.g. time on dialysis). Studies often did not describe these parameters in detail. Although the risk of bias, as assessed by the Newcastle-Ottawa Scale, was generally low for most studies, within the constraints of observational study design, studies were at risk of selection bias and residual confounding. Many study outcomes were reported in ways that did not allow direct comparison or meta-analysis. It is uncertain whether HHD, compared to ICHD, may be associated with a decrease in cardiovascular death (RR 0.92, 95% CI 0.80 to 1.07; 2 NRSIs, 30,900 participants; very low certainty evidence) or all-cause death (RR 0.80, 95% CI 0.67 to 0.95; 9 NRSIs, 58,984 patients; very low certainty evidence). It is also uncertain whether HHD may be associated with a decrease in hospitalisation rate (MD -0.50 admissions per patient-year, 95% CI -0.98 to -0.02; 2 NRSIs, 834 participants; very low certainty evidence), compared with ICHD. Compared with ICHD, it is uncertain whether HHD may be associated with receipt of kidney transplantation (RR 1.28, 95% CI 1.01 to 1.63; 6 NRSIs, 10,910 participants; very low certainty evidence) and a shorter recovery time post-dialysis (MD -2.0 hours, 95% CI -2.73 to -1.28; 2 NRSIs, 348 participants; very low certainty evidence). It remains uncertain if HHD may be associated with decreased systolic blood pressure (SBP) (MD -11.71 mm Hg, 95% CI -21.11 to -2.46; 4 NRSIs, 491 participants; very low certainty evidence) and decreased left ventricular mass index (LVMI) (MD -17.74 g/m2, 95% CI -29.60 to -5.89; 2 NRSIs, 130 participants; low certainty evidence). There was insufficient data to evaluate the relative association of HHD and ICHD with fatigue or vascular access outcomes. Patient-reported outcome measures were reported using 18 different measures across 11 studies (QoL: 6 measures; mental health: 3 measures; symptoms: 1 measure; impact and view of health: 6 measures; functional ability: 2 measures). Few studies reported the same measures, which limited the ability to perform meta-analysis or compare outcomes. It is uncertain whether HHD is more cost-effective than ICHD, both in the first (SMD -1.25, 95% CI -2.13 to -0.37; 4 NRSIs, 13,809 participants; very low certainty evidence) and second year of dialysis (SMD -1.47, 95% CI -2.72 to -0.21; 4 NRSIs, 13,809 participants; very low certainty evidence).

AUTHORS' CONCLUSIONS

Based on low to very low certainty evidence, HHD, compared with ICHD, has uncertain associations or may be associated with decreased cardiovascular and all-cause death, hospitalisation rate, slower post-dialysis recovery time, and decreased SBP and LVMI. HHD has uncertain cost-effectiveness compared with ICHD in the first and second years of treatment. The majority of studies included in this review were observational and subject to potential selection bias and confounding, especially as patients treated with HHD tended to be younger with fewer comorbidities. Variation from study to study in the choice of outcomes and the way in which they were reported limited the ability to perform meta-analyses. Future research should align outcome measures and metrics with other research in the field in order to allow comparison between studies, establish outcome effects with greater certainty, and avoid research waste.

The use of Tablo continuous veno-venous haemodialysis to rapidly remove lithium in a patient with severe lithium toxicity

We report a case of severe, life-threatening lithium toxicity in a patient with bipolar I disorder who presented with altered mental status and acute renal failure. At admission, serum lithium level was well above toxic levels (>2 mEq/L). The signs and symptoms of lithium toxicity significantly improved after treatment with continuous veno-venous haemodialysis (CVVHD). The patient was discharged with no neurological or renal sequelae. Herein is the first case report using the Tablo CVVHD system to treat severe lithium toxicity.

Two Years' Experience of Intensive Home Hemodialysis with the Physidia S3 System: Results from the RECAP Study

The RECAP study reports results and outcomes (clinical performances, patient acceptance, cardiac outcomes, and technical survival) achieved with the S³ system used as an intensive home hemodialysis (HHD) platform over a three-year French multicenter study. Ninety-four dialysis patients issued from ten dialysis centers and treated more than 6 months (mean follow-up: 24 months) with S³ were included. A two-hour treatment time was maintained in 2/3 of patients to deliver 25 L of dialysis fluid, while 1/3 required up to 3 h to achieve 30 L. The additional convection volume produced by means of the SeCoHD tool (internal filtration backfiltration) was 3 L/session, and the net ultrafiltration produced to achieve dry weight was 1.4 L/session. On a weekly basis, an average 156 L of dialysate corresponding to 94 L of urea clearance when considering 85% dialysate saturation under low flow conditions was delivered. Such urea clearance was equivalent to 9.2 [8.0-13.0] mL/min weekly urea clearance and a standardized Kt/V of 2.5 [1.1-4.5]. The predialysis concentration of selected uremic markers remained remarkably stable over time. Fluid volume status and blood pressure were adequately controlled by means of a relatively low ultrafiltration rate (7.9 mL/h/kg). Technical survival on S³ was 72% and 58% at 1 and 2 years, respectively. The S³ system was easily handled and kept by patients at home, as indicated by technical survival. Patient perception was improved, while treatment burden was reduced. Cardiac features (assessed in a subset of patients) tended to improve over time. Intensive hemodialysis relying on the S³ system offers a very appealing option for home treatment with quite satisfactory results, as shown in the RECAP study throughout a two-year follow-up time, and offers the best bridging solution to kidney transplantation.

The coronavirus disease 2019 pandemic: the disruptor that maintenance dialysis never anticipated

PURPOSE OF REVIEW

The novel coronavirus 2019 (COVID-19) pandemic has upended maintenance dialysis in the United States. I review changes in prevalence, incidence, mortality, and other clinical outcomes among patients undergoing dialysis since March 2020, highlighting vulnerabilities in the current system and opportunities for improved care in the future.

RECENT FINDINGS

The number of dialysis patients in the United States declined between March 2020 and March 2021, an unprecedented year-over-year drop in the census. Some of the decline can be attributed to an early drop in patients initiating dialysis but most of the decline can be attributed to excess mortality. Kidney transplants also declined during the early part of the pandemic. Home dialysis utilization increased during 2020 but that increase was largely in line with secular trends. The rate of hospitalization for causes other than COVID-19 fell significantly during 2020.

SUMMARY

The epidemiology of dialysis in the United States is clearly modifiable, as it reflects decisions to initiate treatment, prescribe home therapies, and hospitalize patients with acute medical needs. On the other hand, some outcomes are powerfully guided by health outcomes in the general population, thus limiting the ability of dialysis providers and nephrologists to influence outcomes.

A Novel Substrate-Inspired Fluorescence-Based Albumin Detection Improves Assessment of Clinical Outcomes in Hemodialysis Patients Receiving a Nursing Nutrition Intervention

Background

Albumin level does not precisely reflect nutritional status. We aimed to investigate the impact of a nutrition intervention on hemodialysis patients by use of fluorescence-based plasma albumin (FPA) detection.

Material/Methods

Eighty patients underwent maintenance hemodialysis for more than half a year and had a mean albumin <3.5 g/dL for over 3 months. The subjects were randomly divided into either a Control Group (CG) or an Intervention Group (IG). The IG received nutritional supplementation, and the CG group received routine nutritional support for 12 months. FPA and plasma albumin (PA) concentrations were measured. The fluorescence probe 1,3-Dichloro-7-hydroxy-9,9-dimethyl-2(9H)-acridone methyl biphenyl benzoate was used in FPA detection. Quality of life was estimated using WHOQOL-BREF (Quality of Life Scale developed through the World Health Organization), the 36-Item Short-Form Survey (SF-36), and the 6-minute walking test (6MWT).

Results

After a 6-month and a 12-month intervention, PA and FPA concentrations increased, and the increase in FPA concentration was higher than that of PA in the IG group (P<0.05). Comparatively, the parameters of quality of life and 6MWT were improved in the IG group (P<0.05) but there were only minor changes in the CG group (P>0.05). There is an obvious association between the changes in FPA concentration and the parameters of quality of life and 6MWT but not PA.

Conclusions

Use of the fluorescence probe improves the detection sensitivity of plasma albumin and provides a potential method to assess clinical outcomes in hemodialysis patients.

Funding Innovative Dialysis Technology in the United States: Home Dialysis and the ESRD Transitional Add-on Payment for New and Innovative Equipment and Supplies (TPNIES)

Innovative, patient-centered, and pragmatic dialysis technologies are urgently needed to accommodate the growing national interest in home dialysis use. To help achieve this goal, the US Centers for Medicare & Medicaid Services (CMS) are expanding reimbursement for eligible home dialysis machines through an existing payment mechanism, the transitional add-on payment for new and innovative equipment and supplies (TPNIES). This mechanism incentivizes the early adoption of innovative equipment into practice by reimbursing dialysis providers up to 26% of the total cost of approved home dialysis machines. Machines are evaluated for TPNIES eligibility using prespecified substantial clinical improvement (SCI) criteria that are derived from the Inpatient Prospective Payment System (for non-nephrology technologies). Although the SCI criteria may be suitable for some non-nephrology technologies, they have not been adapted to consider the unique and complex care inherent in home dialysis. Thus, many of the SCI criteria appear unsuitable for home dialysis machines. To better incentivize innovation, CMS should develop nephrology-specific transparent and pragmatic criteria for TPNIES. In this perspective, we provide an overview of the TPNIES payment mechanism, highlight areas of concern within the policy, and offer solutions for improving TPNIES that could better promote the adoption of new home dialysis machines.

Economic Impact of Home Hemodialysis

Home hemodialysis (HD) is growing in the United States, but the economics of the modality are largely unknown, especially considering the unique aspects of home HD in the United States . In this review, I focus on details of Medicare coverage, which directly applies to most patients on dialysis and influences the policies of private insurers. Key details in Medicare comprise the relationship between home dialysis training and initial Medicare eligibility, reimbursement for home HD training, coverage of additional HD treatments (ie., in excess of 3 treatments per week), and monthly capitated payments to nephrologists. The overarching narrative is that frequent home HD directly increases Medicare costs for outpatient dialysis, but these added costs can be mitigated by lower inpatient expenditures if increased HD treatment frequency lowers the risk of cardiovascular hospitalization and infection control is emphasized. I also review recent international literature; conventional home HD exhibits a superior cost profile, whereas frequent home HD is generally cost-effective over multiple treatment years (ie, if early technique failure is avoided). Out-of-pocket expenses for patients should be considered. The future economics of home HD in the United States will be determined by new equipment, new adaptations of the modality, and new payment models.

Innovations to Increase Home Hemodialysis Utilization: The Transitional Care Unit

A large proportion of patients undergoing incident dialysis start in-center hemodialysis with suboptimal preparation and predialysis education. Transitional care units deliver a structured program by dedicated staff, with less patient-to-staff ratios than in regular in-center dialysis care, with the goals of supporting the emotional and physical well-being of patients while providing them with education and equipping them with the right tools to start their journey on dialysis. Key components of these programs include an emphasis on patient activation and self-management, educating and supporting patients to make informed modality choices, timely coordination of care, and an integrated approach to formation and use of the dialysis access. While data are still limited on best practices and on outcomes of these programs at a large scale, endorsing the model of transitional care units is a step in the right direction to fill the gap in our current care system.

Self-care training using the Tablo hemodialysis system

INTRODUCTION

Recently published results of the investigational device exemption (IDE) trial using the Tablo hemodialysis system confirmed its safety and efficacy for home dialysis. This manuscript reports additional data from the Tablo IDE study on the training time required to be competent in self-care, the degree of dependence on health care workers and caregivers after training was complete, and participants' assessment of the ease-of-use of Tablo.

METHODS

We collected data on the time required to set up concentrates and the Tablo cartridge prior to treatment initiation. We asked participants to rate system setup, treatment, and takedown on a Likert scale from 1 (very difficult) to 5 (very simple) and if they had required any assistance with any aspect of treatment over the prior 7 days. In a subgroup of 15 participants, we recorded the number of training sessions required to be deemed competent to do self-care dialysis.

FINDINGS

Eighteen men and 10 women with a mean age of 52.6 years completed the study. Thirteen had previous self-care experience using a different dialysis system. Mean set up times for the concentrates and cartridge were 1.1 and 10.0 minutes, respectively. Participants with or without previous self-care experience had similar set-up times. The mean ease-of-use score was 4.5 or higher on a scale from 1 to 5 during the in-home phase. Sixty-five percent required no assistance at home and on average required fewer than four training sessions to be competent in managing their treatments. Results were similar for participants with or without previous self-care experience.

CONCLUSIONS

Participants in the Tablo IDE trial were able to quickly learn and manage hemodialysis treatments in the home, found Tablo easy to use, and were generally independent in performing hemodialysis.

Patient-reported outcomes from the investigational device exemption study of the Tablo hemodialysis system

INTRODUCTION

We recently completed an Investigational Device Exemption (IDE) study in which 30 patients were enrolled (13 patients previously on home hemodialysis (HHD) and 17 patients new to HHD) and treated with the Tablo Hemodialysis System (Outset Medical, Inc., San Jose, CA) for 8 weeks in-center and 8 weeks in-home with an interim 2-4 week transition period for home training.

METHODS

In addition to assessments of urea kinetics, events related to safety, and operational issues (e.g., alarm resolution), we obtained data on several parameters of health-related quality of life, including time to recovery (TTR), the EQ-5D-5L (a well-validated measure of general health status), and the quality of sleep and related symptoms, to further assess the safety of HHD with Tablo. We compared results obtained during the in-center and in-home phases of the trial.

RESULTS

Twenty-eight of 30 patients (93%) completed all trial periods. Adherence to the prescribed four treatments per week schedule was 96% in-center and 99% in-home. Median TTR was 1.5 hours (10th, 90th percentile range 0.17 to 12, mean TTR 3.68 ± 5.88 hours) during the in-center and 2 hours (10th, 90th percentile range 0 to 6.0, mean TTR 3.04 ± 5.14 hours) during the at-home phase (Wilcoxon signed rank p = 0.57). Median index values on the EQ-5D-5L were similar during the in-center (0.832, 10th, 90th percentile range 0.617 to 1, mean 0.817 ± 0.165) and in-home (0.826, 10th, 90th percentile range 0.603 to 1, mean 0.821 ± 0.163) trial phases (Wilcoxon signed rank p = 0.36). Patients reported feeling alert or well-rested with little difficulty falling or staying asleep or feeling tired and worn out when using Tablo in either environment.

CONCLUSION

When using Tablo in-home, patients reported similar TTR, general health status, and sleep quality and related symptoms compared to using Tablo in-center. (294 words).