Choice of Hemodialysis Access in Older Adults: A Cost-Effectiveness Analysis

Cost-effectiveness analysis of autogenous arteriovenous fistula, arteriovenous graft, and tunneled-cuffed catheter for hemodialysis in patients with end-stage kidney disease in Southern China

OBJECTIVES

To evaluate the cost-effectiveness of three permanent vascular accesses for maintenance hemodialysis patients from a hospital perspective throughout 5 years, which is the average life expectancy of patients with end-stage kidney disease.

SUBJECTS AND METHODS

We conducted a EuroQol(EQ-5D) questionnaire survey between January 2021 and March 2021 with 250 patients to estimate the health utility of various states in patients under different hemodialysis vascular access. We designed a Markov model and conducted a cost-effectiveness analysis to compare the cost-effectiveness of three hemodialysis vascular access in Guangzhou throughout 5 years.

RESULTS

The mean costs were US$44,481 with tunneled-cuffed catheter (TCC), and US$68,952 and US$59,247 with arteriovenous graft (AVG) and autogenous arteriovenous fistula (AVF), respectively. The mean quality-adjusted life-years (QALYs) was 1.41 with TCC, and 2.37 and 2.73 with AVG and AVF, respectively. AVG had an incremental cost-effectiveness ratio (ICER) of US$25,491 per QALY over TCC; AVF had an ICER of -US$26,958 per QALY over AVG. At a willingness to pay below US$10,633.8 per QALY, TCC is likely the most cost-effective vascular access. At any willingness to pay between US$10,633.8 and US$30,901.4 per QALY, AVF is likely the most cost-effective vascular access.

CONCLUSION

These findings illustrate the value of AVF given its relative cost-effectiveness to other hemodialysis modalities. Although AVG costs much more than TCC for slightly higher QALYs than TCC, AVG still has a greater advantage over TCC for patients with longer life expectancy due to its lower probability of death.

Adaptation process of decellularized vascular grafts as hemodialysis access in vivo

Arteriovenous grafts (AVGs) have emerged as the preferred option for constructing hemodialysis access in numerous patients. Clinical trials have demonstrated that decellularized vascular graft exhibits superior patency and excellent biocompatibility compared to polymer materials; however, it still faces challenges such as intimal hyperplasia and luminal dilation. The absence of suitable animal models hinders our ability to describe and explain the pathological phenomena above and in vivo adaptation process of decellularized vascular graft at the molecular level. In this study, we first collected clinical samples from patients who underwent the construction of dialysis access using allogeneic decellularized vascular graft, and evaluated their histological features and immune cell infiltration status 5 years post-transplantation. Prior to the surgery, we assessed the patency and intimal hyperplasia of the decellularized vascular graft using non-invasive ultrasound. Subsequently, in order to investigate the in vivo adaptation of decellularized vascular grafts in an animal model, we attempted to construct an AVG model using decellularized vascular grafts in a small animal model. We employed a physical-chemical-biological approach to decellularize the rat carotid artery, and histological evaluation demonstrated the successful removal of cellular and antigenic components while preserving extracellular matrix constituents such as elastic fibers and collagen fibers. Based on these results, we designed and constructed the first allogeneic decellularized rat carotid artery AVG model, which exhibited excellent patency and closely resembled clinical characteristics. Using this animal model, we provided a preliminary description of the histological features and partial immune cell infiltration in decellularized vascular grafts at various time points, including Day 7, Day 21, Day 42, and up to one-year post-implantation. These findings establish a foundation for further investigation into the in vivo adaptation process of decellularized vascular grafts in small animal model.

Hemodialysis vascular access in elderly patients: A comprehensive review

The number of elderly patients initiating hemodialysis (HD) increased considerably over the past decade. Arteriovenous fistulas (AVFs) are the preferred vascular access (VA) type in most HD patients. Choice of VA for older hemodialysis patients presents a challenge. The higher incidence of comorbidities, longer AVF maturation times, risk of primary failure, risk of patency loss, and shorter life expectancy are important factors to consider. In this review we provide a comprehensive analysis on maturation rates, primary failure, patency, and mortality regarding vascular access in patients older than 75 years of age.

CMS ESRD quality incentive program has not improved patient dialysis vascular access

PURPOSE

Over 468,000 patients in the United States use hemodialysis to manage End Stage Renal Disease (ESRD). The purpose of this study was to determine whether the dialysis access Clinical Performance Measures (CPMs) of Centers for Medicare & Medicaid Services (CMS) ESRD Quality Incentive Program (QIP) have increased arteriovenous fistula (AVF) rates and decreased long-term tunneled hemodialysis catheter (TDC) rates among hemodialysis patients in United States.

METHODS

Retrospective observational study: evaluated reported AVF and long-term TDC rates of 4804 dialysis facilities which reported dialysis access data as part of the ESRD QIP from Payment Year (PY) 2014-2020. Facilities were also sorted by specific additional criteria to examine disparities in dialysis access.

RESULTS

Mean AVF rates of included facilities increased from 63.7% in PY 2014 to 67.2% in PY 2016 (p < 0.05), did not change in PY 2017 (p > 0.05), and declined significantly in PY 2018-2020 to 64.1% in PY 2020, near AVF rates at the inception of program. Long-term TDC rates decreased from 10.4% in PY 2014 to 9.88% in PY 2015 (p < 0.05), then increased in PY 2015-PY 2020 to rates higher than at the inception of program, at 11.8% in PY 2020 (p < 0.05). Facilities serving majority Black ZIP Code Tabulation Areas (ZCTAs) or ZCTAs with median income <$45,000 achieved significantly lower AVF rates (p < 0.05) with no significant difference in long-term TDC rates (p > 0.05). AVF rates correlated positively and long-term TDC rates correlated negatively with star rating of facilities (p < 0.05).

CONCLUSION

As one of the first financial QIPs in healthcare, the ESRD QIP has not achieved the stated goals of the CMS to increase AVF access rates above 68% and reduce long-term TDC clinical rates below 10%. Systemic disparities in race, geographic region, economic status, healthcare access, and education of providers and patients prevent successful attainment of goal metrics.

Economics of drug-coated balloons for arteriovenous fistula stenosis in Japan and Korea based on the IN.PACT AV access trial

AIM

The recent IN.PACT AV Access study found drug-coated balloon therapy to be associated with reduced reinterventions compared to percutaneous transluminal angioplasty using standard balloons in the management of arteriovenous fistula stenosis. The economic implications of drug-coated balloon use in Asia, including Japan and Korea, remain unknown.

METHODS

A decision-analytic model was developed to calculate strategy-specific costs for Korea and Japan through 5-year follow-up. The analysis assumed maintained therapy benefit beyond current trial follow-up of 1 year in the base case, with several alternative scenarios explored in sensitivity analysis. Costs were derived from claims and reimbursement data, and projections were evaluated at 3 and 5 years post-index procedure.

RESULTS

Model-projected access circuit reintervention events for drug-coated versus standard balloons were 1.70 versus 2.76 (-1.06) and 2.53 versus 4.10 (-1.57) at 3 and 5 years in the base case. Corresponding 3- and 5-year costs were ₩6 211 103 versus ₩7 605 553 (-₩1 394 451) and ₩7 766 051 versus ₩10 124 954 (-₩2 358 904) in Korea, and ¥1 469 824 versus ¥1 504 161 (-¥34 337) and ¥1 956 931 versus ¥2 106 632 (-¥149 701) in Japan. In scenario analyses, drug-coated balloons remained cost saving at 3- and 5-year follow-up in Korea, but required up to 5 years to reach cost-savings in Japan. Drug-coated balloon use in reinterventions increased projected savings, as did younger treatment age.

CONCLUSION

Treatment of arteriovenous fistulas with the IN.PACT AV drug-coated balloon, based on preliminary data, may lead to meaningful reductions in reintervention costs that would render it cost-saving at timeframes of around 1 year in Korea and between 3 and 5 years in Japan.

Hemodialysis Initiation in Oldest-Old Patients: A Case Series

With an increase in the number of older adults worldwide, the oldest-old population, defined as individuals over the age of 90, is also growing. Japan is now facing the problem of a “super-aged society” in which over 21% of the population is aged over 65. The oldest-old constituted 1.8% (2.31 million) of the Japanese population in 2019. Such individuals have special health-care needs. In cases of acute or chronic (or both) renal failure in the oldest-old, it becomes difficult to decide whether dialysis should be initiated. The issue is controversial, and there is some debate on whether dialysis should be avoided in elderly people because of their frailty or if it should be initiated to enable them to spend their remaining years with their families by improving their quality of life. Herein, we describe our experience in 4 cases of hemodialysis initiated in patients over the age of 90. In our experience, dialysis enabled them to spend the rest of their lives with their families, which could not have been possible without it. Although further studies are needed, we concluded that oldest-old individuals in good general health could be eligible for and benefit from hemodialysis.

Quantifying The Costs of Creating and Maintaining Hemodialysis Access in An All-Payer Rate-Controlled Health System

OBJECTIVES

The creation and maintenance of durable hemodialysis access is critically important for reducing patient morbidity and controlling overall costs within health systems. Our objective was to quantify the costs associated with hemodialysis access creation and its maintenance over time within a rate-controlled health system where charges equate to payments.

METHODS

The Maryland Health Services Cost Review Commission administrative claims database was used to identify patients who underwent first-time access creation from 2012-2020. Patients were identified using CPT codes for access creation, and costs were accrued for the initial encounter and all subsequent outpatient access-related encounters. T-tests and Wilcoxon tests were used to compare reinterventions and access-related costs ($USD) between arteriovenous fistulae (AVF) and arteriovenous grafts (AVG). Multivariable modeling was used to quantify the association of access type with charge variation.

RESULTS

Overall, 12,716 patients underwent first-time access creation (69.3% AVF vs. 30.7% AVG). There was no difference in freedom from reintervention between the two access types at any point following creation (HR: 1.03, 95%CI: 0.97-1.10); however, AVF were associated with a lower number of cumulative reinterventions (1.50 vs. 2.24) compared to AVG (P<0.0001). AVF was associated with lower overall costs in the year of creation ($9,388 vs. $13,539, P<0.0001), a difference that remained significant over the subsequent 3 years. The lower costs associated with AVF were present both in the costs associated with creation and subsequent maintenance. On multivariable analysis, AVF was associated with a $3,557 reduction in total access-related costs versus AVG (95%CI -$3828, -3287).

CONCLUSION

AVF require fewer interventions and are associated with lower costs at placement and over the first three years of maintenance compared to AVG. The use of AVF for first-time hemodialysis access represents an opportunity for healthcare savings in appropriately selected patients with a high preoperative likelihood of AVF maturation.

Cost-effectiveness analysis of radiobasilic and brachiobasilic arteriovenous fistulas in hemodialysis patients

We evaluated the cost and efficacy of radiobasilic and brachiobasilic arteriovenous fistula (AVF) methods in terms of forearm autogenous arteriovenous access in hemodialysis patients. We used a decision tree to compare the cost-effectiveness of proximal radiobasilic AVF (pRBAVF) and brachiobasilic AVF (BBAVF), considering the mean direct medical costs and patency rates. The overall mean cost of pRBAVF per patient (1767.59 Turkish lira [TL]) was lower than that of BBAVF (1877.99 TL). Also, the mean patency duration per patient was higher for pRBAVF (25.72 months) than BBAVF (20.21 months). The incremental cost-effectiveness ratio (ICER) showed that pRBAVF was 20.04-fold more effective than BBAVF. The monthly ICERs also favored pRBAVF, which was less costly and more effective. The pRBAVF provided clinical and economic benefits for hemodialysis patients requiring forearm autogenous arteriovenous access. pRBAVF was more effective in terms of patency than BBAVF, and was also less expensive.

Arteriovenous Vascular Access-Related Procedural Burden Among Incident Hemodialysis Patients in the United States

RATIONALE & OBJECTIVE

As the proportion of arteriovenous fistulas (AVFs) compared with arteriovenous grafts (AVGs) in the United States has increased, there has been a concurrent increase in interventions. We explored AVF and AVG maturation and maintenance procedural burden in the first year of hemodialysis.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

Patients initiating hemodialysis from July 1, 2012, to December 31, 2014, and having a first-time AVF or AVG placement between dialysis initiation and 1 year (N = 73,027), identified using the US Renal Data System (USRDS).

PREDICTORS

Patient characteristics.

OUTCOME

Successful AVF/AVG use and intervention procedure burden.

ANALYTICAL APPROACH

For each group, we analyzed interventional procedure rates during maturation maintenance phases using Poisson regression. We used proportional rate modeling for covariate-adjusted analysis of interventional procedure rates during the maintenance phase.

RESULTS

During the maturation phase, 13,989 of 57,275 patients (24.4%) in the AVF group required intervention, with therapeutic interventional requirements of 0.36 per person. In the AVG group 2,904 of 15,572 patients (18.4%) required intervention during maturation, with therapeutic interventional requirements of 0.28 per person. During the maintenance phase, in the AVF group 12,732 of 32,115 patients (39.6%) required intervention, with a therapeutic intervention rate of 0.93 per person-year. During maintenance phase, in the AVG group 5,928 of 10,271 patients (57.7%) required intervention, with a therapeutic intervention rate of 1.87 per person-year. For both phases, the intervention rates for AVF tended to be higher on the East Coast while those for AVG were more uniform geographically.

LIMITATIONS

This study relies on administrative data, with monthly recording of access use.

CONCLUSIONS

During maturation, interventions for both AVFs and AVGs were relatively common. Once successfully matured, AVFs had lower maintenance interventional requirements. During the maturation and maintenance phases, there were geographic variations in AVF intervention rates that warrant additional study.

Outcomes of arteriovenous fistula in elderly patients on maintenance haemodialysis

BACKGROUND

The optimal vascular access strategy in elderly patients receiving haemodialysis (HD) remains controversial. We aim to report the outcomes of arteriovenous fistula (AVF) in elderly patients initiated on maintenance HD in our centre.

METHODS

Medical records of 688 incident patients initiated on HD from 2010 to 2012 in a tertiary centre were retrospectively reviewed. Patients' characteristics and AVF outcomes were compared among those < 65 years (non-elderly), ≥ 65-75 years (early elderly) and ≥ 75 years (late elderly).

RESULTS

There were 418 non-elderly, 184 early elderly and 86 late elderly patients. There is a higher proportion of brachiocephalic and brachiobasilic fistula created in the late elderly (24.9% vs. 37.0% vs. 41.8%, p = 0.001). The outcomes of accesses created were comparable in the 3 age groups with similar proportions of functional AVFs (80.4% vs. 79.3% vs. 75.6%, p = 0.832) and comparable 1-, 3- and 5-year primary and secondary patency rates (p = 0.351 and 0.282, respectively). However, a longer maturation time (2.78 vs. 2.86 vs. 3.72 months, p = 0.010) and a higher mean number of interventions to assist maturation of the first AVF were required in late elderly patients (0.19 vs. 0.22 vs. 0.35, p = 0.014). Following AVF creation, median patient survival in the non-elderly, early and late elderly was 65.2 vs. 55.1 vs. 49.8 months respectively.

CONCLUSION

AVFs created in elderly patients have comparable outcomes compared to non-elderly patients although more interventions are required to assist maturation with a longer maturation time necessitating early access creation to allow for time needed due to maturation delay.

Patency of ePTFE Arteriovenous Graft Placements in Hemodialysis Patients: Systematic Literature Review and Meta-Analysis

Arteriovenous grafts (AVGs) are an appropriate option for vascular access in certain hemodialysis patients. Expanded polytetrafluoroethylene (ePTFE) has become the dominant material for such grafts, due in part to innovations in graft design and surgical interventions to reduce complications and improve patency rates. Comprehensive evidence syntheses have not been conducted to update AVG performance in an era in which both access choice and ePTFE graft functioning may have changed. We conducted a systematic review and meta-analysis summarizing outcomes from recent studies of ePTFE AVGs in hemodialysis, following PRISMA standards. Literature searches were conducted in multiple databases to identify observational and interventional studies of AVG patency and infection risk. Primary, primary-assisted, and secondary patency rates were analyzed at 6, 12, 18, and 24 months postplacement. Kaplan-Meier graft survival plots were digitized to recreate individual patient-level data. Patency rates were pooled using a random effects model. We identified 32 studies meeting our selection criteria that were published from 2004 through 2019. A total of 38 study arms of ePTFE grafts were included, representing 3381 AVG accesses placed. The mean primary, primary-assisted, and secondary patency rates at 1 year were 41% (95% CI, 35% to 47%), 46% (95% CI, 41% to 51%), and 70% (95% CI, 64% to 75%), respectively. Mean 24-month patency rates were 28% (95% CI, 22% to 33%), 34% (95% CI, 27% to 41%), and 54% (95% CI, 47% to 61%), respectively. A high degree of heterogeneity across studies was observed. Overall risk of infection was not consistently reported, but among available studies the pooled estimate was 9% per patient-year (95% CI, 6% to 12%). This meta-analysis provides an up-to-date estimate of the performance of ePTFE AVGs, within the context of improved graft designs and improved interventional techniques.

Impacts of age, diabetes, gender, and access type on costs associated with vascular access among Chinese patients on hemodialysis

OBJECTIVES

Examine the impacts of age, diabetes, gender, and access type on vascular access (VA) associated costs among Chinese hemodialysis (HD) patients.

METHODS

We retrospectively included patients whose first permanent VA was created at the West China Hospital. Clinical characteristics, maturation, intervention, utilization, and exchange of every VA, as well as VA-related infection were collected. The study period for each patient was from HD initiation to the last follow-up. VA-related costs, including those for placement and intervention procedures, were calculated according to the standards set in 2019 for Chinese tertiary hospitals. Mann-Whitney U and Chi-square tests were conducted for comparisons between groups.

RESULTS

A total of 358 Chinese HD patients experienced functionally 143 arteriovenous fistula (AVF), 22 arteriovenous graft (AVG), and 439 tunneled cuffed central venous catheter (tcCVC) during a median study period of 26 (IQR 13-44) months, of which 42.5% used more than one permanent VA. The median annual VA-related cost in the groups of age >75 years and ⩽75 years, diabetes and non-diabetes, male and female, was $525 and $397 (p = 0.016), $459 and $462 (p = 0.64), $476 and $445 (p = 0.94), respectively. The median monthly costs for AVF ($18), AVG ($289), and tcCVC ($37) were significantly different.

CONCLUSION

HD patients aged >75 years had significantly higher annual VA-related costs. However, the annual VA-related costs did not differ across the diabetes groups or the gender groups. AVF was the most cost-effective permanent VA type in China, partly due to the inexpensive materials used compared to AVG or tcCVC.

Practice patterns of dialysis access and outcomes in patients wait-listed early for kidney transplantation

BACKGROUND

Early kidney transplantation (KT) is the best option for patients with end-stage kidney disease, but little is known about dialysis access strategy in this context. We studied practice patterns of dialysis access and how they relate with outcomes in adults wait-listed early for KT according to the intended donor source.

METHODS

This study from the REIN registry (2002-2014) included 9331 incident dialysis patients (age 18-69) wait-listed for KT before or by 6 months after starting dialysis: 8342 candidates for deceased-donor KT and 989 for living-donor KT. Subdistribution hazard ratios (SHR) of KT and death associated with hemodialysis by catheter or peritoneal dialysis compared with arteriovenous (AV) access were estimated with Fine and Gray models.

RESULTS

Living-donor candidates used pretransplant peritoneal dialysis at rates similar to deceased-donor KT candidates, but had significantly more frequent catheter than AV access for hemodialysis (adjusted OR 1.25; 95%CI 1.09-1.43). Over a median follow-up of 43 (IQR: 23-67) months, 6063 patients received transplants and 305 died before KT. Median duration of pretransplant dialysis was 15 (7-27) months for deceased-donor recipients and 9 (5-15) for living-donor recipients. Catheter use in deceased-donor candidates was associated with a lower SHR for KT (0.88, 95%CI 0.82-0.94) and a higher SHR for death (1.53, 95%CI 1.14-2.04). Only five deaths occurred in living-donor candidates, three of them with catheter use.

CONCLUSIONS

Pretransplant dialysis duration may be quite long even when planned with a living donor. Advantages from protecting these patients from AV fistula creation must be carefully evaluated against catheter-related risks.

Arteriovenous Fistula Placement, Maturation, and Patency Loss in Older Patients Initiating Hemodialysis

RATIONALE & OBJECTIVE

The current clinical guidelines for vascular access do not have specific recommendations for older hemodialysis patients. Our study aimed to determine the association of age with arteriovenous fistula (AVF) placement, maturation, and primary and secondary patency loss among older hemodialysis recipients.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

A US national cohort of incident hemodialysis patients 67 years or older (N = 43,851) assembled from the US Renal Data System.

EXPOSURE

Age at dialysis initiation.

OUTCOMES

AVF placement, maturation, primary patency loss, and abandonment.

ANALYTICAL APPROACH

Cause-specific and subdistribution proportional hazards models were used to examine the association of age and AVF outcomes, with kidney transplantation, peritoneal dialysis, and death treated as competing events. Age cutoff was identified by restricted cubic splines. We compared crude and inverse probability-weighted cumulative incidence functions using Gray's test.

RESULTS

As compared with those aged 67-<77 years, patients 77 years or older had significantly lower probabilities of AVF placement (adjusted cause-specific HR [cHR], 0.96 [95% CI, 0.92-0.99]; adjusted subdistribution HR [sHR], 0.92 [95% CI, 0.89-0.95]; Gray's test P < 0.001) and maturation (adjusted cHR, 0.95 [95% CI, 0.91-0.99]; adjusted sHR, 0.93 [95% CI, 0.90-0.97]; P < 0.001). However, age was not associated with AVF primary (adjusted cHR, 1.05 [95% CI, 1.00-1.11]; adjusted sHR, 1.04 [95% CI, 0.99-1.09]; P = 0.09) or secondary (adjusted cHR, 1.06 [95% CI, 0.94-1.20]; adjusted sHR, 1.05 [95% CI, 0.93-1.18]; P = 0.4) patency loss.

LIMITATIONS

Reliance on administrative claims to ascertain AVF outcomes.

CONCLUSIONS

The likelihood of AVF maturation is an important consideration for vascular access planning. Age alone should not be the basis for excluding older dialysis patients from AVF creation because maintenance of fistula patency was not reduced with older age despite a modest reduction in fistula maturation.

A randomized pilot study to evaluate graft versus fistula vascular access strategy in older patients with advanced kidney disease: results of a feasibility study

BACKGROUND

Although older adults encompass almost half of patients with advanced chronic kidney disease, it remains unclear which long-term hemodialysis vascular access type, arteriovenous fistula or arteriovenous graft, is optimal with respect to effectiveness and patient satisfaction. Clinical outcomes based on the initial AV access type have not been evaluated in randomized controlled trials. This pilot study tested the feasibility of randomizing older adults with advanced kidney disease to initial arteriovenous fistula versus graft vascular access surgery.

METHODS

Patients 65 years or older with pre-dialysis chronic kidney disease or incident end-stage kidney disease and no prior arteriovenous vascular access intervention were randomized in a 1:1 ratio to undergo surgical placement of a fistula or a graft after providing informed consent. Trial feasibility was evaluated as (i) recruitment of ≥ 70% of eligible participants, (ii) ≥ 50 to 70% of participants undergo placement of index arteriovenous access within 90 to 180 days of enrollment, respectively, (iii) ≥ 80% adherence to study-related assessments, and (iv) ≥ 70% of participants who underwent index arteriovenous access placement will have a follow-up duration of ≥ 12 months after index surgery date.

RESULTS

Between September 2018 and October 2019, 81% (44/54) of eligible participants consented and were enrolled in the study; 11 had pre-dialysis chronic kidney disease, and 33 had incident or prevalent end-stage kidney disease. After randomization, 100% (21/21) assigned to arteriovenous fistula surgery and 78% (18/23) assigned to arteriovenous graft surgery underwent index arteriovenous access placement within a median (1st, 3rd quartile) of 5.0 (1.0, 14.0) days and 13.0 (5.0, 44.3) days, respectively, after referral to vascular surgery. The completion rates for study-specific assessments ranged between 40.0 and 88.6%. At median follow-up of 215.0 days, 5 participants expired, 7 completed 12 months of follow-up, and 29 are actively being followed. Assessments of grip strength, functional independence, and vascular access satisfaction were completed by > 85% of patients who reached pre-specified post-operative assessment time point.

CONCLUSIONS

Results from this study reveal it is feasible to enroll and randomize older adults with advanced kidney disease to one of two different arteriovenous vascular access placement surgeries. The study can progress with minor protocol adjustments to a multisite clinical trial.

TRIAL REGISTRATION

Clinical Trials ID, NCT03545113.

Cost-effectiveness analysis of immediate access arteriovenous grafts versus standard grafts for hemodialysis

OBJECTIVE

Immediate-access arteriovenous grafts (IAAVGs), or early cannulation arteriovenous grafts (AVGs), are more expensive than standard grafts (sAVGs) but can be used immediately after placement, reducing the need for a tunneled dialysis catheter (TDC). We hypothesized that a decrease in TDC-related complications would make IAAVGs a cost-effective alternative to sAVGs.

METHODS

We constructed a Markov state-transition model in which patients initially received either an IAAVG or an sAVG and a TDC until graft usability; patients were followed through multiple subsequent access procedures for a 60-month time horizon. The model simulated mortality and typical graft- and TDC-related complications, with parameter estimates including probabilities, costs, and utilities derived from previous literature. A key parameter was median time to TDC removal after graft placement, which was studied under both real-world (7 days for IAAVG and 70 days for sAVG) and ideal (no TDC placed with IAAVG and 1 month for sAVG) conditions. Costs were based on current Medicare reimbursement rates and reflect a payer perspective. Both microsimulation (10,000 trials) and probabilistic sensitivity analysis (10,000 samples) were performed. The willingness-to-pay threshold was set at $100,000 per quality-adjusted life-year (QALY).

RESULTS

IAAVG placement is a dominant strategy under both real-world ($1201.16 less expensive and 0.03 QALY more effective) and ideal ($1457.97 less expensive and 0.03 QALY more effective) conditions. Under real-world parameters, the result was most sensitive to the time to TDC removal; IAAVGs are cost-effective if a TDC is maintained for ≥23 days after sAVG placement. The mean catheter time was lower with IAAVG (3.9 vs 8.7 months; P < .0001), as was the mean number of access-related infections (0.55 vs 0.74; P < .0001). Median survival in the model was 29 months. Overall mortality was similar between groups (76.3% vs 76.7% at 5 years; P = .33), but access-related mortality trended toward improvement with IAAVG (6.1% vs 6.8% at 5 years; P = .052).

CONCLUSIONS

The Markov decision analysis model supported our hypothesis that IAAVGs come with added initial cost but are ultimately cost-saving and more effective. This apparent benefit is due to our prediction that a decreased number of catheter days per patient would lead to a decreased number of access-related infections.

Non-invasive tunnelled catheter reposition (NTCR): A simple and safe method to restore central tunnelled catheter function for haemodialysis

Despite all efforts, still many end-stage kidney disease (ESKD) patients are dialysed using a central tunnelled catheter (CTC) as vascular access. When the CTC blood flow becomes ineffective, a number of protocols are advised. However, all of them are time- and cost-consuming. The manoeuvre of a non-invasive tunnelled catheter reposition (NTCR) was introduced to restore the CTC function. NTCR was based on gentle movements of the CTC, with or without a simultaneous flushing of the CTC lines, which resulted in a quick reposition of the CTC tip. This study comprises the analysis of a total of 297 NTCRs, which were performed in 114 patients, thus enabling an effective blood flow after 133 procedures (44.7%).Partially effective blood flow followed 123 procedures (41.4%), and it failed altogether in 41 cases (13.9%). Overall, 86% of conducted NTCRs improved the CTC patency to perform a haemodialysis session. The procedure could be successfully repeated, with a similar result after the first and the second attempt. Complications were observed only after 3.4% of all interventions. The novel NTCR manoeuvre was safe and effective in the majority of the CTC dysfunction episodes. It seemed to reduce fibrinolytic usage, allowed an immediate haemodialysis session commencement, therefore, it might save both the costs and the nursing staff time.

Delayed conversion from central venous catheter to non-catheter hemodialysis access associates with an increased risk of death: A retrospective cohort study based on data from a large dialysis provider

Background

Hemodialysis initiation using a central venous catheter (CVC) poses an increased risk of death. Conversion to an arterio‐venous graft or fistula (AVF, AVG) improves outcomes. The relationship of primary dialysis access and timing of conversion from CVC to either AVF or AVG to all‐cause mortality was investigated.

Methods

Two retrospective analyses in incident hemodialysis patients commencing treatment from January 2010 to December 2014 in dialysis clinics in the United States were conducted. Analysis 1 stratified as per access at initiation and those commencing with CVC were further stratified into (a) those that had a CVC, AVF, or AVG the entire year; (b) those that were converted to either AVF or AVG within either (i) the first or (ii) the second 6 months. Kaplan Meier analysis and Cox regression analysis were employed. Analysis 2 included all CVC patients investigating the relationship between access conversion time and mortality risk using a Cox proportional hazards model depicting the hazard ratio (HR) as a spline function over time.

Results

Two subsets from initial 78,871 patients were studied. In Analysis 1 both AVF (referent) and AVG [HR 1.12 (0.97 to 1.30)] associated with a better outcome than CVC [HR 1.55 (1.38 to 1.74)] during follow‐up. Lower mortality risk was seen for early switch from a CVC to AV access within the first 6 months [HR = 1.04 (0.97–1.13)] compared to a later switch [HR = 1.23 (1.10–1.38)]. Analysis 2 indicated that a CVC to AVF switch resulted in improved survival. Analysis 2 indicated early conversion to confer a survival benefit for CVC to AVG switch.

Discussion and Conclusion

AVF and AVG show a survival benefit over CVC. Early conversion from CVC to either access improves survival. This emphasizes the importance of early preparation for dialysis by creation of an AVF or AVG and to convert CVCs early.

In-hospital mortality among incident hemodialysis older patients in Peru

BACKGROUND

Understanding the pattern of mortality linked to end stage renal disease (ESRD) is important given the increasing ageing population in low- and middle-income countries.

METHODS

We analyzed older patients with ESRD with incident hemodialysis, from January 2012 to August 2017 in one large general hospital in Peru. Individual and health system-related variables were analyzed using Generalized Linear Models (GLM) to estimate their association with in-hospital all-cause mortality. Relative risk (RR) with their 95% confidence intervals (95% CI) were calculated.

RESULTS

We evaluated 312 patients; mean age 69 years, 93.6% started hemodialysis with a transient central venous catheter, 1.7% had previous hemodialysis indication and 24.7% died during hospital stay. The mean length of stay was 16.1 days (SD 13.5). In the adjusted multivariate models, we found higher in-hospital mortality among those with encephalopathy (aRR 1.85, 95% CI 1.21-2.82 vs. without encephalopathy) and a lower in-hospital mortality among those with eGFR ≤7 mL/min (aRR 0.45, 95% CI 0.31-0.67 vs. eGFR>7 mL/min).

CONCLUSIONS

There is a high in-hospital mortality among older hemodialysis patients in Peru. The presence of uremic encephalopathy was associated with higher mortality and a lower estimated glomerular filtration rate with lower mortality.

Computational study on the haemodynamic and mechanical performance of electrospun polyurethane dialysis grafts

Compliance mismatch between an arteriovenous dialysis graft (AVG) and the connected vein is believed to result in disturbed haemodynamics around the graft–vein anastomosis and increased mechanical loading of the vein. Both phenomena are associated with neointimal hyperplasia development, which is the main reason for AVG patency loss. In this study, we use a patient-specific fluid structure interaction AVG model to assess whether AVG haemodynamics and mechanical loading can be optimised by using novel electrospun polyurethane (ePU) grafts, since their compliance can be better tuned to match that of the native veins, compared to gold standard, expanded polytetrafluoroethylene (ePTFE) grafts. It was observed that the magnitude of flow disturbances in the vein and the size of anastomotic areas exposed to highly oscillatory shear (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {OSI} >0.25$$\end{document}OSI>0.25) and very high wall shear stress (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$>40 \hbox { Pa}$$\end{document}>40Pa) were largest for the ePTFE graft. Median strain and von Mises stress in the vein were similar for both graft types, whereas highest stress and strain were observed in the anastomosis of the ePU graft. Since haemodynamics were most favourable for the ePU graft simulation, AVG longevity might be improved by the use of ePU grafts.

Maturing arteriovenous accesses in incident haemodialysis patients and first-year outcomes

INTRODUCTION

Nephrologists have increased arteriovenous access placement in patients with chronic kidney disease. Not yet usable 'maturing' arteriovenous fistulas and grafts are nearly as common as mature arteriovenous fistulas or grafts. Little has been reported about patients initiating haemodialysis with unready arteriovenous fistulas or grafts.

METHODS

The United States Renal Data System records for all adult patients initiating haemodialysis with central venous catheters between July 2010 and December 2011. Patients were categorized by whether a maturing arteriovenous fistula or graft was present. Transition to working arteriovenous fistula or graft was determined from linked Medicare claims. Modality changes and survival were ascertained. A logistic model for one-year survival and a subdistribution hazards model for transition to working arteriovenous fistula or graft, accounting for the competing risk of death, were constructed.

RESULTS

Compared to central venous catheter-only, maturing arteriovenous fistula or graft was associated with access conversion (hazard ratio = 2.23 (2.17-2.30) and 3.25 (2.97-3.56), respectively, p < 0.001 for both). Median time to conversion, among those who transitioned, was 95 days (interquartile range = 56-139) for patients with a maturing arteriovenous graft and 135 days (98-198) with a maturing arteriovenous fistula, versus 193 days (138-256) with central venous catheter-only. Pre-dialysis nephrology care, male sex and non-Caucasian race were associated with access conversion. Patients without a maturing arteriovenous fistula or graft had decreased odds of one-year survival (odds ratio = 0.61 (0.58-0.66), p < 0.001), which attenuated with adjustment for access conversion (adjusted odds ratio = 1.06 (0.98-1.13), p = 0.2).

CONCLUSION

Maturing arteriovenous fistulas or grafts were associated with enhanced first-year survival and increased opportunity for working arteriovenous fistulas or grafts, which may reflect pre-dialysis decision-making, quality of care and comorbid diseases. Central venous catheter exposure was substantial, even among patients with maturing access. Contributory factors prolonging conversion to arteriovenous access need to be identified and addressed.

Hemodialysis vascular access in the elderly-getting it right

Choosing the optimal hemodialysis vascular access for the elderly patient is best achieved by a patient-centered coordinated multidisciplinary team approach that aligns the patient's end-stage kidney disease Life-Plan, i.e., the individual treatment approach (supportive care, time-limited or long-term kidney replacement therapy, or combination thereof) and selection of dialysis modality (peritoneal dialysis versus hemodialysis) with the most suitable dialysis access. Finding the right balance between the patient's preferences, the likelihood of access function and survival, and potential complications in the context of available resources and limited patient survival can be extremely challenging. The framework for choosing the most appropriate vascular access for the elderly presented in this review considers the individual end-stage kidney disease Life-Plan, the patient life expectancy, the likelihood of access function and survival, the timing of dialysis relative to access placement, prior access history, and patient preference. This complex decision-making process should be dynamic in order to accommodate patients' changing needs and life and health circumstances. Effective and timely communication between the patient, their caregivers, and treating team is key to delivering truly patient-centered care. Delivering this care also requires overcoming the limitations of the currently available evidence that is predominantly based on observational data with its inherent risks of bias. While challenging, future randomized controlled studies exploring the risks, benefits, costs, and timing of placement of available access types in the elderly are required to help us "get it right" for our patients.

Beyond the Technical: Determining Real Indications for Vascular Access and Hemodialysis Initiation in End-Stage Renal Disease

Determining valid indications for vascular access creation and hemodialysis initiation in end-stage renal disease requires utilization of verified prognostication tools and recognition of triggers to initiate serious conversations, and implementation of concurrent palliative care and/or hospice care is recommended. Establishment of a multi-disciplinary team that includes consideration of interventionalists in the pre-dialysis medical situation is important. A "catheter best" approach may be the most appropriate for some patients to meet goals of care.

Initiation of maintenance hemodialysis through central venous catheters: study of patients' perceptions based on a structured questionnaire

Background

Despite well-publicized suggestions to utilize arteriovenous fistulae and grafts to initiate hemodialysis, too many patients in the United States start dialysis via central venous catheters despite their well-known association with increased morbidity, mortality, and cost.

Methods

To determine the reasons for this high rate of catheter use, and, ultimately, ways to reduce it, we developed a questionnaire designed to determine where in the process of patient care the process to fistula or graft placement was not completed, thus requiring the use of central venous catheters. The questionnaire was reviewed by several nephrologists not involved with the study. We administered the questionnaire to 52 consecutive hospitalized patients who started maintenance dialysis with catheters at a University-affiliated Hospital and referral center. The questionnaire asked each patient to provide details pertaining to pre-dialysis care, referrals, and follow-through on recommended referrals. If the patient did not see the physician to whom he/she was referred, we asked the reason(s) for such failure.

Results

Patient responses showed that there were two major lapses in the transition from diagnosis of advanced kidney disease to construction of appropriate dialysis access: failure by the patients to see a nephrologist and/or an access surgeon, and failure by physicians to refer patients to an access surgeon. Twenty percent of the patients failed to follow up with either a nephrologist or a surgeon. Only 38% (15/40) of those seen by a nephrologist had been referred to a surgeon.

Conclusions

The quality of care was impaired by lack of referral to surgeons by nephrologists and by lack of follow-through by patients. Areas for improvement include improved communications between physicians and patients and more careful follow-up by both physicians and patients. Several methods of providing better patient care and communication between patients and nephrologists are recommended.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1422-y) contains supplementary material, which is available to authorized users.

Angiography and phlebography in a hemodialysis population: A retrospective analysis of interventional results

OBJECTIVE

To clarify the reasons and beneficial effects and duration of arteriovenous fistula patency after radiological interventions in arteriovenous fistula. The patients investigated were referred due to arteriovenous fistula access flow problems.

MATERIAL AND METHODS

In 174 patients, 522 radiological investigations and endovascular treatments such as percutaneous transluminal angioplasty were analyzed, retrospectively. All investigations were performed due to clinical suspicion of impaired arteriovenous fistula function.

RESULTS

Arterial stenosis was significantly more frequent among patients with diabetic nephropathy (p < 0.001) and interstitial nephritis (p < 0.001). According to the venous stenosis, the diagnosis did not affect the frequency (p = 0.22) or the degree (p = 0.39) of stenosis. The degree of stenosis prior to percutaneous transluminal angioplasty correlated significantly with the degree of remaining stenosis after intervention (p < 0.001). Of the 174 patients, 123 (71%) performed a total of 318 investigations including percutaneous transluminal angioplasty. Repeated percutaneous transluminal angioplasty was performed significantly more often in patients with diabetic nephropathy. The median times to the first percutaneous transluminal angioplasty and to the subsequent percutaneous transluminal angioplasties were 9.5 and 5 months, respectively. Arteriovenous fistula in patients with diabetic nephropathy performed similar to most other diagnoses, although performing more percutaneous transluminal angioplasty/patient than most other diagnoses.

CONCLUSION

Many patients could maintain long-term patency of arteriovenous fistula, including those with diabetic nephropathy, with repeated interventions; this motivates a closer follow-up for these patients. Clinically significant stenosis should be dilated as meticulously and as soon as possible. Occlusions of the arteriovenous fistula in most instances can be successfully thrombolyzed or dilated upon early diagnosis.

Forearm loop arteriovenous grafts preserve and may create new upper arm access sites

INTRODUCTION

This study evaluated the mid-term patency of forearm loop arteriovenous grafts and the dilation of previously inadequate upper arm basilic and cephalic veins after failed forearm loop arteriovenous graft.

METHODS

All access procedures from September 2009 to December 2015 were reviewed. Vein mapping measurements were used to determine whether there was "adequate" upper arm cephalic and/or basilic vein, defined as ⩾3 mm by duplex ultrasound, at the time of forearm loop arteriovenous graft creation. Outcomes of forearm loop arteriovenous graft were compared with upper arm arteriovenous fistula, and primary and cumulative patencies were evaluated.

RESULTS

Thirty-eight forearm loop arteriovenous grafts and 278 upper arm arteriovenous fistulas were created. In the forearm loop arteriovenous graft cohort, nine were inserted with adequate upper arm vein, group A, and 29 were inserted with inadequate upper arm vein, group B. Cumulative patency was lower for forearm loop arteriovenous graft compared with upper arm arteriovenous fistula at 6 months, 1 year, and 2 years (67% vs 91%, 61% vs 85%, and 49% vs 80%, respectively, P < .01). Comparison of group A forearm loop arteriovenous graft and upper arm arteriovenous fistula did not show a statistical difference in cumulative patency at 6 months, 1 year, and 2 years (P = .80, .62, and .70, respectively). Of group B with failed forearm loop arteriovenous graft, 36% became candidates for upper arm arteriovenous fistula with dilation of ipsilateral upper arm cephalic or basilic vein to ⩾3 mm.

CONCLUSION

In this study, forearm loop arteriovenous graft with adequate upper arm vein did not show a statistical difference in mid-term patencies compared with upper arm arteriovenous fistula. For those forearm loop arteriovenous grafts with inadequate upper arm vein, approximately one-third of patients became candidates for upper arm arteriovenous fistula demonstrating the benefits forearm loop arteriovenous graft.

Prescribing Hemodialysis or Hemodiafiltration: When One Size Does Not Fit All the Proposal of a Personalized Approach Based on Comorbidity and Nutritional Status

There is no simple way to prescribe hemodialysis. Changes in the dialysis population, improvements in dialysis techniques, and different attitudes towards the initiation of dialysis have influenced treatment goals and, consequently, dialysis prescription. However, in clinical practice prescription of dialysis still often follows a "one size fits all" rule, and there is no agreed distinction between treatment goals for the younger, lower-risk population, and for older, high comorbidity patients. In the younger dialysis population, efficiency is our main goal, as assessed by the demonstrated close relationship between depuration (tested by kinetic adequacy) and survival. In the ageing dialysis population, tolerance is probably a better objective: "good dialysis" should allow the patient to attain a stable metabolic balance with minimal dialysis-related morbidity. We would like therefore to open the discussion on a personalized approach to dialysis prescription, focused on efficiency in younger patients and on tolerance in older ones, based on life expectancy, comorbidity, residual kidney function, and nutritional status, with particular attention placed on elderly, high-comorbidity populations, such as the ones presently treated in most European centers. Prescription of dialysis includes reaching decisions on the following elements: dialysis modality (hemodialysis (HD) or hemodiafiltration (HDF)); type of membrane (permeability, surface); and the frequency and duration of sessions. Blood and dialysate flow, anticoagulation, and reinfusion (in HDF) are also briefly discussed. The approach described in this concept paper was developed considering the following items: nutritional markers and integrated scores (albumin, pre-albumin, cholesterol; body size, Body Mass Index (BMI), Malnutrition Inflammation Score (MIS), and Subjective Global Assessment (SGA)); life expectancy (age, comorbidity (Charlson Index), and dialysis vintage); kinetic goals (Kt/V, normalized protein catabolic rate (n-PCR), calcium phosphate, parathyroid hormone (PTH), beta-2 microglobulin); technical aspects including vascular access (fistula versus catheter, degree of functionality); residual kidney function and weight gain; and dialysis tolerance (intradialytic hypotension, post-dialysis fatigue, and subjective evaluation of the effect of dialysis on quality of life). In the era of personalized medicine, we hope the approach described in this concept paper, which requires validation but has the merit of providing innovation, may be a first step towards raising attention on this issue and will be of help in guiding dialysis choices that exploit the extraordinary potential of the present dialysis "menu".

Planning and evaluation for vascular access in the elderly

Vascular access is of vital importance for patients requiring dialysis therapies. AV fistulas have been endorsed by many professional societies as the access of choice, however, subsequent creation does not go without consequences. As the population ages and patients become more medically complex, access failure has become a major cause of treatment complication. For the elderly, this is especially true and there are multiple decision points that require careful reflection before an AVF is placed. This article reviews access considerations for AVF placement in the elderly population and considers the possibility that the fistula first approach to vascular access should not be an absolute.

Elderly patient: which vascular access? Choice and management of vascular access in the elderly patient

The optimal vascular access for elderly patients remains a challenge due to the difficult balance between risks and benefits in a population with increased comorbidity and decreased survival. Long dependence to central vein catheter, patient comorbidities, life expectancy, and complication rates are important influencing the indications for arteriovenous fistula or an arteriovenous graft. Although central vein catheters are simpler way to start a hemodialysis treatment, elderly patients are also at higher risk of death from infection or other complications associated with them more than for younger patients. The discussion revolves around the following key questions:

What are the limiting factors for a vascular access in the elderly patients? Central venous catheter—is it still an option for elderly patients? Is still the autologous arteriovenous fistula playing a pivotal role as hemodialysis access in the elderly patients? Are there any real surgical contraindication to perform a vascular access in elderly patients? Is the old age a limiting factor for the vascular access management?

Central venous catheters for chronic hemodialysis: Is "last choice" never the "right choice"?

Since the publication of the first vascular access clinical practice guidelines in 1997, the global nephrology community has dedicated significant time and resources toward increasing the prevalence of arteriovenous fistulas and decreasing the prevalence of central venous catheters for hemodialysis. These efforts have been bolstered by observational studies showing an association between catheter use and increased patient morbidity and mortality. To date, however, no randomized comparisons of the outcomes of different forms of vascular access have been conducted. There is mounting evidence that much of the difference in patient outcomes may be explained by patient factors, rather than choice of vascular access. Some have called into question the appropriateness of fistula creation for certain patient populations, such as those with limited life expectancy and those at high risk of fistula-related complications. In this review, we explore the extent to which catheters and fistulas exhibit the characteristics of the "ideal" vascular access and highlight the significant knowledge gaps that exist in the current literature. Further studies, ideally randomized comparisons of different forms of vascular access, are required to better inform shared decision making.