A Patient-Centered Approach to Hemodialysis Vascular Access in the Era of Fistula First

Hemodialysis Vascular Access: A Historical Perspective on Access Promotion, Barriers, and Lessons for the Future

This review describes the history of vascular access for hemodialysis (HD) over the past 8 decades. Reliable, repeatable vascular access for outpatient HD began in the 1960s with the Quinton-Scribner shunt. This was followed by the autologous Brecia-Cimino radial-cephalic arteriovenous fistula (AVF), which dominated HD vascular access for the next 20 years. Delayed referral and the requirement of 1.5-3 months for AVF maturation led to the development of and increasing dependence on synthetic arteriovenous grafts (AVGs) and tunneled central venous catheters, both of which have higher thrombosis and infection risks than AVFs. The use of AVGs and tunneled central venous catheters increased progressively to the point that, in 1997, the first evidence-based clinical practice guidelines for HD vascular access recommended that they only be used if a functioning AVF could not be established. Efforts to promote AVF use in the United States during the past 2 decades doubled their prevalence; however, recent practice guidelines acknowledge that not all patients receiving HD are ideally suited for an AVF. Nonetheless, improved referral for AVF placement before dialysis initiation and improved conversion of failing AVGs to AVFs may increase AVF use among patients in whom they are appropriate.

Slowly moving the needle away from Fistula First

OBJECTIVE

In 2019, the management of end-stage kidney disease (ESKD) shifted away from "Fistula First" (FF) to "ESKD Life-Plan: Patient Life-Plan First then Access Needs." Indeed, some patients exhibit such excessive comorbidity that even relatively minor vascular surgery may be complicated. The purpose of this study was to retrospectively assess complications and mortality (and delineate operative futility) in patients undergoing arteriovenous fistula (AVF) creation in the FF era.

METHODS

Consecutive AVFs created in a single institution before 2021 were retrospectively reviewed. Operative futility was defined as never-accessed fistula, no initiation of dialysis, failure of access maturation (despite secondary intervention), hemodialysis access-induced distal ischemia requiring ligation, early loss of secondary patency, and/or patient mortality within the first 6 postoperative months.

RESULTS

A total of 401 AVFs were created including radial-cephalic (44%), brachial-cephalic (41%), and brachial-basilic (15%) constructions. Patients exhibited a mean age of 69 ± 15 years; 63% were male, and most (74%) were already being hemodialyzed at the time of fistula creation. Forty-five patients (11%) suffered a cardiac event, and five patients died (1%) within 90 days of their access surgery. Perioperative cardiac events were significantly more common after age 80 (19% vs 8%; P = .004); age >80 years was an independent predictor of major 90-day complications (odds ratio [OR], 1.88; 95% confidence interval [CI], 1.04-3.39; P = .036) and the sole independent predictor of major morbidity defined as cardiopulmonary complications, stroke, or death within the first year (OR, 2.01; 95% CI, 1.24-3.25; P = .004). Operative futility was encountered in 52% of the cohort (n = 208 patients): 40% (n = 160) of primary AVFs failed to mature despite assistance, 19% (n = 77) had lost secondary patency by 6 months, 13% of patients (n = 53) were never started on dialysis after access creation, 4% (n = 16) were dead by 6 months, 2% of AVFs (n = 10) matured but were never accessed, and 2% (n = 9) required ligation for hemodialysis access-induced distal ischemia. Not surprisingly, the sole independent protector against operative futility was that catheter-based dialysis had been established prior to AVF creation (OR, 0.36; 95% CI, 0.22-0.59; P < .01).

CONCLUSIONS

Approximately 50% of primary AVF operations performed in the aggressive FF era were deemed futile. Octogenarians were particularly prone to futility and complications during this era. A paradigm shift, from FF to an "ESKD Life-Plan" will, hopefully, more thoughtfully match vascular access strategies to individual patient needs.

Alignment Among Patient, Caregiver, and Health Care Provider Perspectives on Hemodialysis Vascular Access Decision-Making: A Qualitative Study

Background

Updates to the Kidney Disease Outcomes Quality Initiative Clinical Practice Guideline for Vascular Access emphasize the "right access, in the right patient, at the right time, for the right reasons." Although this implies a collaborative approach, little is known about how patients, their caregivers, and health care providers engage in vascular access (VA) decision-making.

Objective

To explore how the perspectives of patients receiving hemodialysis, their caregivers, and hemodialysis care team align and diverge in relation to VA selection.

Design

Qualitative descriptive study.

Setting

Five outpatient hemodialysis centers in Calgary, Alberta.

Participants

Our purposive sample included 19 patients receiving maintenance hemodialysis, 2 caregivers, and 21 health care providers (7 hemodialysis nurses, 6 VA nurses, and 8 nephrologists).

Methods

We conducted semi-structured interviews with consenting participants. Using an inductive thematic analysis approach, we coded transcripts in duplicate and characterized themes addressing our research objective.

Results

While participants across roles shared some perspectives related to VA decision-making, we identified areas where views diverged. Areas of alignment included (1) optimizing patient preparedness-acknowledging decisional readiness and timing, and (2) value placed on trusting relationships with the kidney care team-respecting decisional autonomy with guidance. Perspectives diverged in the following aspects: (1) differing VA priorities and preferences-patients' emphasis on minimizing disruptions to normalcy contrasted with providers' preferences for fistulas and optimizing biomedical parameters of dialysis; (2) influence of personal and peer experience-patients preferred pragmatic, experiential knowledge, whereas providers emphasized informational credibility; and (3) endpoints for VA review-reassessment of VA decisions was prompted by access dissatisfaction for patients and a medical imperative to achieve a functioning access for health care providers.

Limitations

Participation was limited to individuals comfortable communicating in English and from urban, in-center hemodialysis units. Few informal caregivers of people receiving hemodialysis and younger patients participated in this study.

Conclusions

Although patients, caregivers, and healthcare providers share perspectives on important aspects of VA decisions, conflicting priorities and preferences may impact the decisional outcome. Findings highlight opportunities to bridge knowledge and readiness gaps and integrate shared decision-making in the VA selection process.

A Comparative Study of Continuous Versus Interrupted Suturing Technique in Creating a Vascular Access for Hemodialysis: An Institutional-Based Experience

Background Arteriovenous fistulas (AVFs) are considered the first and best access for patients with end-stage renal disease who need permanent vascular access for hemodialysis over arteriovenous grafts and central venous catheters for reasons that have been well-established. Poor early patency rates pose the biggest challenge in creating vascular access as they cause increased morbidity and economic/psychological concerns among patients. To minimize such effects, it is critical to use a patient-centered approach and carefully choose patients for AVF access creation. This study aimed to compare the primary patency of distal vascular access provided by continuous suturing versus that provided by interrupted suturing. Methodology This prospective study was conducted in the urology department of a superspecialty, tertiary care center from November 2021 to November 2022. Patency was assessed immediately after surgery (on the table), one month later, and six months later by palpating thrill and auscultating bruit. A total of 50 patients between the ages of 18 and 70 years who met the inclusion criteria were randomly assigned to two groups of 25 each. Results The baseline characteristics of both groups were comparable. At six months (p = 0.09), the continuous suturing group was observed to be somewhat better than the interrupted suturing group, with no significant difference in immediate and one-month patency rates. When compared to the continuous suturing group, the primary patency failure rate was significantly higher in the interrupted suturing group. Conclusions Thus, under appropriate circumstances, continuous sutures can be performed with greater ease, resulting in anastomosis that is as patent as that performed with interrupted sutures.

Evaluation of outcomes with permanent vascular access in an elderly Korean population based on the National Health Insurance Service database

INTRODUCTION

As nearly half of patients with end-stage kidney disease (ESKD) who initiate hemodialysis (HD) are over 65 years old (commonly defined as elderly), the fistula first strategy is controversial even in HD patients ≥65 years.

METHODS

In Korea's National Health Insurance Service database from 2008 to 2019, 41,989 elderly (≥ 65 years) HD patients were retrospectively reviewed to identify their clinical characteristics and outcomes. Vascular access (VA) patencies, risk factors associated with patencies and patient survival between arteriovenous fistula (AVF) and arteriovenous graft (AVG) were compared.

RESULTS

Elderly AVF group (n = 28,467) had superior primary, primary assisted, and secondary patencies than elderly AVG group (n = 13,522) (all p values are <0.001). Patient survival was also better in the elderly AVF group than in the elderly AVG (p < 0.001). In multivariate Cox regression analyses for diverse outcomes, AVG (vs. AVF) was identified as a risk factor for all-cause mortality (adjusted hazard ratio [HR]: 1.307; 95% confidence interval [CI]: 1.272-1.343; p < 0.001), primary patency (adjusted HR: 1.745; 95% CI: 1.701-1.790; p < 0.001), primary-assisted patency (adjusted HR: 2.163; 95% CI: 2.095-2.233; p < 0.001), and secondary patency (adjusted HR: 3.718; 95% CI: 3.533-3.913; p < 0.001).

CONCLUSION

Our study demonstrated that as a permanent VA for HD, AVF should be strongly considered in elderly (≥ 65 years) ESKD Korean patients. The age limit for AVF creation in ESKD patients should be adjusted more upward.

Association between arteriovenous access flow and ventricular function: A cross-sectional study

Background

Permanent hemodialysis access comes with a myriad of problems on top of the well-known benefits; flow disturbances, risk of infection and revision being among them. All of these could eventually lead to impaired cardiac function. Even so, the relationship between impaired cardiac function due to arteriovenous access in patients undergoing hemodialysis has not been clearly described. This study aimed to analyze the relationship of flow in an artificial arteriovenous access with left and right ventricular function in patients with chronic kidney disease (CKD) undergoing hemodialysis at a referral hospital in Indonesia.

Material and methods

This was a cross sectional study with consecutive sampling technique. Samples were patients with CKD undergoing hemodialysis at Dr. Soetomo General Hospital from December 2021to January 2022. A total of 47 patients who met the inclusion criteria underwent Doppler ultrasound to assess arteriovenous access flow and transthoracic echocardiography to assess left and right ventricle function.

Results

From 47 patients, 26 (55.3%) had high arteriovenous access flow. The clinical characteristics of the patients between the high and low arteriovenous access flow groups were not significantly different. We found that the value of left ventricular ejection fraction in the non-high-flow access group was significantly higher than the high-flow access group (p < 0.05). Other than that, the median right ventricle fractional area changes in the non-high-flow access group was also higher than the high-flow access group (p < 0.05).

Conclusion

Arteriovenous access flow as measured by Doppler ultrasonography has a significant relationship with impaired left and right ventricular functions based on systolic function parameters from echocardiography.

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There is an association between arteriovenous access flow and ventricular function.

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The higher the access flow, the lower the left ventricular systolic function.

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The higher the access flow, the lower the right ventricular systolic function.

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It is important to periodically evaluate the access flow of hemodialysis patients.

Chronic Kidney Disease and Heart Failure-Everyday Diagnostic Challenges

Is advanced chronic kidney disease (CKD) a cardiac “no man’s land”? Chronic heart failure (HF) is widely believed to be one of the most serious medical challenges of the 21st century. Moreover, the number of patients with CKD is increasing. To date, patients with estimated glomerular filtration rates <30 mL/min/1.73 m² have frequently been excluded from large, randomized clinical trials. Although this situation is slowly changing, in everyday practice we continue to struggle with problems that are not clearly addressed in the guidelines. This literature review was conducted by an interdisciplinary group, which comprised a nephrologist, internal medicine specialists, and cardiologist. In this review, we discuss the difficulties in ruling out HF for patients with advanced CKD and issues regarding the cardiotoxicity of dialysis fistulas and the occurrence of pulmonary hypertension in patients with CKD. Due to the recent publication of the new HF guidelines by the European Society of Cardiology, this is a good time to address these difficult issues. Contrary to appearances, these are not niche issues, but problems that affect many patients.

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.

High-flow arteriovenous fistula is not associated with increased extracellular volume or right ventricular dysfunction in haemodialysis patients

BACKGROUND

High-output congestive heart failure secondary to high-flow arteriovenous fistula (AVF) has been reported in haemodialysis (HD) patients. As high-flow AVF (HFA) would be expected to result in fluid retention, we conducted an observational study to characterize the relationship between AVF flow (Qa) and extracellular water (ECW) in HD patients.

METHODS

We measured Qa by ultrasound dilution in prevalent HD outpatients with an AVF in two dialysis centres. The ECW:total body water (TBW) ratio was measured both pre- and post-dialysis by multifrequency bioimpedance analysis. Transthoracic echocardiograms (TTEs) were performed as part of routine clinical management.

RESULTS

We included 140 patients, mean age 62.7 ± 15.7 years, 60.7% male, 47.9% diabetic and 22.9% with coronary revascularization. Mean Qa was 1339 ± 761 mL/min and 22 (15.7%) patients had HFA defined as Qa >2.0 L/min. Qa was positively associated with an upper arm AVF (P = 0.005), body mass index (P = 0.012) and N-terminal pro-brain natriuretic peptide (NT-proBNP) (P = 0.047) and negatively associated with diabetes (P < 0.001) and coronary revascularization (P = 0.005). The ECW:TBW ratio was positively associated with age (P < 0.001), Davies comorbidity index (P = 0.034), peripheral vascular disease (P = 0.030) and NT-proBNP (P = 0.002) and negatively associated with serum albumin (P < 0.001). Qa was not associated with the ECW:TBW ratio (P = 0.744). TTE parameters were not associated with Qa.

CONCLUSIONS

In our outpatient HD cohort, high AVF flow was not associated with ECW expansion, either pre- or post-dialysis when accounting for potential confounders. By controlling ECW, high access flow should not necessarily be perceived as a threat to cardiovascular physiology.

Analysis of pathogenic distribution and drug resistance of catheter-related blood stream infection in hemodialysis patients with vein tunneled cuffed catheter

The catheter related blood stream infections (CRBSI) in hemodialysis (HD) patients with vein tunneled cuffed catheter (TCC) and misuse of antibiotic in clinical practice seriously affected the prognosis of MHD patients. The present study aimed to investigate the pathogen distribution and drug resistance of CRBSI in HD patients with TCC to guide clinical empirical pharmacy. The clinical data of 75 HD patients with TCC diagnosed with CRBSI between January 2011 and March 2015 were retrospectively collected, and the distribution and drug resistance of pathogens were analyzed. In 75 HD patients with TCC diagnosed with CRBSI, there were 33 patients with positive blood culture, and the positive rate of blood culture was 44%. The majority of the 33 pathogens were Gram-positive bacteria (22 strains, accounting for 66.7%). Gram-positive cocci hardly resisted to vancomycin and linezolid, while the resistance rate to penicillin G nearly reached to 100%. Gram-negative bacilli had low resistance rates to carbapenems and quinolone antibiotics, and the resistance rate to cephalosporins antibioticsexceeding 50%. The positive rate of blood culture in 75 HD patients with TCC diagnosed with CRBSI is low. The pathogens resulting in CRBSI in HD patients are mainly Gram-positive bacteria which are significantly resistant to penicillin G, and have a low resistance rate to methicillin. Gram-negative bacteria have high resistance rates to commonly used antibiotics. The pathogen examination should be performed as early as possible and effective antibiotics should be chosen according to drug sensitivity test results in CRBSI in HD patients.

Implication of Trends in Timing of Dialysis Initiation for Incidence of End-stage Kidney Disease

IMPORTANCE

In the last 2 decades, there have been notable changes in the level of estimated glomerular filtration rate (eGFR) at which patients initiate long-term dialysis in the US and around the world. How changes over time in the likelihood of dialysis initiation at any given eGFR level in at-risk patients are associated with the population burden of end-stage kidney disease (ESKD) has not been not well defined.

OBJECTIVE

To examine temporal trends in long-term dialysis initiation by level of eGFR and to quantify how these patterns are associated with the number of patients with ESKD.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study analyzing data obtained from a large, integrated health care delivery system in Northern California from 2001 to 2018 in successive 3-year intervals. Included individuals, ranging in number from as few as 983 122 (2001-2003) to as many as 1 844 317 (2016-2018), were adult members with 1 or more outpatient serum creatinine levels determined in the prior year.

MAIN OUTCOMES AND MEASURES

One-year risk of initiating long-term dialysis stratified by eGFR levels. Multivariable logistic regression was performed to assess temporal trends in each 3-year cohort with adjustment for age, sex, race, and diabetes status. The potential change in dialysis initiation in the final cohort (2016-2018) was estimated using the relative difference between the standardized risks in the initial cohort (2001-2003) and the final cohort.

RESULTS

In the initial 3-year cohort, the mean (SD) age was 55.4 (16.3) years, 55.0% were women, and the prevalence of diabetes was 14.9%. These characteristics, as well as the distribution of index eGFR, were stable across the study period. The likelihood of receiving dialysis at eGFR levels of 10 to 24 mL/min/1.73 m2 generally increased over time. For example, the 1-year odds of initiating dialysis increased for every 3-year interval by 5.2% (adjusted odds ratio, 1.052; 95% CI, 1.004-1.102) among adults with an index eGFR of 20 to 24 mL/min/1.73 m2, by 6.6% (adjusted odds ratio, 1.066; 95% CI, 1.007-1.130) among adults with an eGFR of 16 to 17 mL/min/1.73 m2, and by 5.3% (adjusted odds ratio, 1.053; 95% CI, 1.008-1.100) among adults with an eGFR of 10 to 13 mL/min/1.73 m2, adjusting for age, sex, race, and diabetes. The incidence of new cases of ESKD was estimated to have potentially been 16% (95% CI, 13%-18%) lower if there were no changes in system-level practice patterns or other factors besides timing of initiating long-term dialysis from the initial 3-year interval (2001-2003) to the final interval (2016-2018) assessed in this study.

CONCLUSIONS AND RELEVANCE

The present results underscore the importance the timing of initiating long-term dialysis has on the size of the population of individuals with ESKD.

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.

Comparison of vascular access patency and patient survival between native arteriovenous fistula and synthetic arteriovenous graft according to age group

INTRODUCTION

Arteriovenous fistula (AVF) is historically known to be the ideal option for vascular access (VA) for hemodialysis compared with arteriovenous graft (AVG). However, this approach has been recently questioned in the aging population because of their poor vessel quality and multiple comorbidities.

METHODS

Data from a total of 2200 patients from the VA category of The Catholic Medical Center nephrology registry from March 2009 to February 2017 were analyzed. We compared VA patency and patient survival between two groups, AVF and AVG, according to age.

FINDINGS

Compared with the AVG group, survival benefit in the AVF group continued even in patients ≥80 years. In the whole population, all the primary patency (PP), primary-assisted patency (PAP), and secondary patency (SP) measures were superior in the AVF group. With regard to subgroups, PP was comparable between the two groups in patients ≥65 years, whereas PAP and SP were superior in the AVF group even in septuagenarian patients who are from 70 to 79 years old. In patients ≥80 years, all the patency measures were comparable between the two groups. When the separate comparison of lower-arm AVF (or upper-arm AVF) and AVG, lower-arm AVF failed to demonstrate its superiority in any kind of patency in septuagenarian patients compared with AVG, whereas upper-arm AVF demonstrated its superiority in PAP and SP in septuagenarian patients. However, even upper-arm AVF failed to demonstrate its superiority in any kind of patency in patients ≥80 years.

DISCUSSION

Arteriovenous fistula if using upper-arm vessel showed the superior VA patency up to septuagenarian patients, whereas, in HD patients ≥80 years, AVF and AVG were comparable in VA patency.

KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research.

Prospective Audit to Study urokinaSe use to restore Patency in Occluded centRal venous caTheters (PASSPORT 1)

OBJECTIVES

Tunnelled central venous catheters dysfunction can be defined as failure to provide blood flow above 200 mL/min during dialysis often caused by thrombosis. Although urokinase is used routinely for thrombolysis, there is wide variation in dose regimens. A multidisciplinary group was formed to address this issue and offer guidance.

METHODS

Dialysis centres that used urokinase in the United Kingdom took part in a prospective study to determine the safety and outcomes of thrombolysis using agreed protocols. Data were collected anonymously from September 2017 until February 2018. Catheter blood flow was measured before and after the following interventions: catheter dwell or push locks with 12,500-50,000 IU or catheter infusion with 100,000-250,000 IU of urokinase. Interventions were repeated if the blood flow remained below 200 mL/min.

RESULTS

10 centres took part and recruited 200 patients; 45.5% were female and 54.5% were male with mean age of 63.6 (±15.2) years. The cumulative success rate for thrombolysis was 90.5% after first intervention, 97% after second intervention, and 99% after more than 2 interventions. Although there was trend towards benefit with dose increments, the success rate between push/dwell locks and high-dose infusion of urokinase was not significantly different (p = 0.069). Seventeen (8.5%) tunnelled central venous catheters were removed due to failure of treatment. No urokinase-related adverse events were reported.

CONCLUSION

In this study, urokinase was safe and efficacious; there was no difference between dwell and push locks. There was some benefit with high-dose infusion of urokinase compared to the dwell and push lock.

Predicting Technical Success after Fistuloplasty: An Analysis of 176 Procedures

BACKGROUND

Significant stenoses in arteriovenous fistulae (AVFs) or arteriovenous grafts (AVGs) with limitation of flow and dialysis inadequacy should prompt consideration for fistuloplasty. We sought to identify fistulae, lesions, and patient-specific variables, which predict for outcomes after fistuloplasty.

METHODS

Data were extracted retrospectively from a renal access database from 2011 to 2016 of patients undergoing fistuloplasty. Demographics, comorbidities, outcomes of intervention, and flow rates documented on preintervention and postintervention duplex were collected. Secondary analysis of factors associated with postfistuloplasty flow rates of >600 mL/min, previously shown to be predictive of not requiring future intervention, was performed.

RESULTS

Of 204 attempted fistuloplasties, 176 were completed. One hundred forty (79.5%) were native AVFs and 34 (19.3%), AVGs (no data for 2). Median stenosis treated was 75%, with a majority (43.8%) in the proximal outflow vein. Flow rate on duplex after fistuloplasty was significantly better in AVFs (mean improvement 189.2 mL/min) than that in AVGs (mean improvement 51.8 mL/min; P = 0.034). Greatest flow improvement occurred for needling site stenotic lesions compared with other locations (from anastomosis to central vein) but was not significant. Brachio-brachial or brachio-axillary AVGs did significantly (P < 0.05) worse than all other fistulae types. The presence of hypertension was predicted for postfistuloplasty flow rate of >600 mL/min.

CONCLUSIONS

Flow rates after fistuloplasty vary depending on the type of fistula treated and the presence of hypertension. Knowledge of this can lead to better patient selection and counseling for fistuloplasty.

The associations of hemodialysis access type and access satisfaction with health-related quality of life

OBJECTIVE

In addition to age and comorbidities, health-related quality of life (HRQOL) is known to predict mortality in hemodialysis (HD) patients. Understanding the association of vascular access type with HRQOL can help surgeons to provide patient-centered dialysis access recommendations. We sought to understand the impact of HD access type on HRQOL.

METHODS

We conducted a cross-sectional prospective study of community-dwelling prevalent HD patients in Pittsburgh, Pennsylvania. We assessed patient satisfaction with their access using the Vascular Access Questionnaire (VAQ) and HRQOL with the Short Form Health Survey. We compared access satisfaction and HRQOL across access types. We used logistic regression modeling to evaluate the association of access type with satisfaction and multivariate analysis of variance to evaluate the association of both of these variables on HRQOL.

RESULTS

We surveyed 77 patients. The mean age was 61.8 ± 15.9 years. Arteriovenous fistula (AVF) was used by 62.3%, tunneled dialysis catheter (TDC) by 23.4%, and arteriovenous graft (AVG) by 14.3%. There was a significant difference in satisfaction by access type with lowest median VAQ score (indicating highest satisfaction) in patients with AVF followed by TDC and AVG (4.5 vs 6.5 vs 7.0; P = .013). Defining a VAQ score of <7 to denote satisfaction, AVF patients were more likely to be satisfied with their access, compared with TDC or AVG (77% vs 56% vs 55%; P = NS). Multivariate regression analysis yielded a model that predicted 46% of the variance of VAQ score; important predictors of dissatisfaction included <1 year on dialysis (β = 3.36; P < .001), increasing number of access-related hospital admissions in the last year (β = 1.69; P < .001), and AVG (β = 1.72; P = .04) or TDC (β = 1.67; P = .02) access. Mean physical and mental QOL scores (the composite scores of Short Form Health Survey) were not different by access type (P = .49; P = .41). In an additive multivariate analysis of variance with the two composite QOL scores as dependent variables, 25.8% of the generalized variance in HRQOL (effect size) was accounted for by access satisfaction with only an additional 3% accounted for by access type.

CONCLUSIONS

HD patients experience greatest satisfaction with fistula, and access satisfaction is significantly associated with better HRQOL. Controlling for access satisfaction, there is no significant independent association of access type on HRQOL. Future research should investigate the relationship between access satisfaction, adherence to dialysis regimens, mortality, and the consequent implications for patient-centered care.

Fistula First Initiative: Historical Impact on Vascular Access Practice Patterns and Influence on Future Vascular Access Care

The vascular access is the lifeline for the hemodialysis patient. In the United States, the Fistula First Breakthrough Initiative (FFBI) has been influential in improving use of arteriovenous fistulas (AVF) in prevalent hemodialysis patients. Currently, prevalent AVF rates are near the goal of 66% set forth by the original FFBI. However, central venous catheter (CVC) rates remain very high in the United States in patients initiating hemodialysis, nearly exceeding 80%. A new direction of the of the FFBI has focused on strategies to reduce CVC use, and subsequently the FFBI has now been renamed the "Fistula First-Catheter Last Initiative". However, an AVF may not be the best vascular access in all hemodialysis patients, and arteriovenous grafts (AVG) and CVCs may be appropriate and the best access for a subset of hemodialysis patients. Unfortunately, there still remains very little emphasis within vascular access initiatives and guidelines directed towards evaluation of the individual patient context, specifically patients with poor long-term prognoses and short life expectancies, patients with multiple comorbidities, patients who are more likely to die than reach end stage renal disease (ESRD), and patients of elderly age with impaired physical and cognitive function. Given the complexity of medical and social issues in advanced CKD and ESRD patients, planning, selection, and placement of the most appropriate vascular access are ideally managed within a multidisciplinary setting and requires consideration of several factors including national vascular access guidelines. Thus, the evolution of the FFBI should underscore the need for multidisciplinary health teams with a major emphasis placed on "the right access for the right patient" and improving the patient's overall quality of life.

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

BACKGROUND AND OBJECTIVES

Although arteriovenous fistulas have been found to be the most cost-effective form of hemodialysis access, the relative benefits of placing an arteriovenous fistula versus an arteriovenous graft seem to be least certain for older adults and when placed preemptively. However, older adults' life expectancy is heterogeneous, and most patients do not undergo permanent access creation until after dialysis initiation. We evaluated cost-effectiveness of arteriovenous fistula placement after dialysis initiation in older adults as a function of age and life expectancy.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using a hypothetical cohort of patients on incident hemodialysis with central venous catheters, we constructed Markov models of three treatment options: (1) arteriovenous fistula placement, (2) arteriovenous graft placement, or (3) continued catheter use. Costs, utilities, and transitional probabilities were derived from existing literature. Probabilistic sensitivity analyses were performed by age group (65-69, 70-74, 75-79, 80-84, and 85-89 years old) and quartile of life expectancy. Costs, quality-adjusted life-months, and incremental cost-effectiveness ratios were evaluated for up to 5 years.

RESULTS

The arteriovenous fistula option was cost effective compared with continued catheter use for all age and life expectancy groups, except for 85-89 year olds in the lowest life expectancy quartile. The arteriovenous fistula option was more cost effective than the arteriovenous graft option for all quartiles of life expectancy among the 65- to 69-year-old age group. For older age groups, differences in cost-effectiveness between the strategies were attenuated, and the arteriovenous fistula option tended to only be cost effective in patients with life expectancy >2 years. For groups for which the arteriovenous fistula option was not cost saving, the cost to gain one quality-adjusted life-month ranged from $2294 to $14,042.

CONCLUSIONS

Among older adults, the cost-effectiveness of an arteriovenous fistula placed within the first month of dialysis diminishes with increasing age and lower life expectancy and is not the most cost-effective option for those with the most limited life expectancy.

Examining the Association between Hemodialysis Access Type and Mortality: The Role of Access Complications

BACKGROUND AND OBJECTIVES

People receiving hemodialysis to treat kidney failure need a vascular access (a fistula, a graft, or a central venous catheter) to connect to the blood purification machine. Higher rates of access complications are considered the mechanism responsible for the excess mortality observed among catheter or graft users versus fistula users. We tested this hypothesis using mediation analysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied incident patients who started hemodialysis therapy from North America, Europe, and Australasia (the Dialysis Outcomes and Practice Patterns Study; 1996-2011). We evaluated the association between access type and time to noninfectious (e.g., thrombosis) and infectious complications of the access (mediator model) and the relationship between access type and time-dependent access complications with 6-month mortality from the creation of the first permanent access (outcome model). In mediation analysis, we formally tested whether access complications explain the association between access type and mortality.

RESULTS

Of the 6119 adults that we studied (mean age =64 [SD=15] years old; 58% men; 47% patients with diabetes), 50% had a permanent catheter for vascular access, 37% had a fistula, and 13% had a graft. During the 6-month study follow-up, 2084 participants (34%) developed a noninfectious complication of the access, 542 (8.9%) developed an infectious complication, and 526 (8.6%) died. Access type predicted the occurrence of access complications; both access type and complications predicted mortality. The associations between access type and mortality were nearly identical in models excluding and including access complications (hazard ratio, 2.00; 95% confidence interval, 1.55 to 2.58 versus hazard ratio, 2.01; 95% confidence interval, 1.56 to 2.59 for catheter versus fistula, respectively). In mediation analysis, higher mortality with catheters or grafts versus fistulas was not the result of increased rates of access complications.

CONCLUSIONS

Hemodialysis access complications do not seem to explain the association between access type and mortality. Clinical trials are needed to clarify whether these associations are causal or reflect confounding by underlying disease severity.

Cost-effectiveness Analysis of Vascular Access Referral Policies in CKD

BACKGROUND

The optimal timing of vascular access referral for patients with chronic kidney disease who may need hemodialysis (HD) is a pressing question in nephrology. Current referral policies have not been rigorously compared with respect to costs and benefits and do not consider patient-specific factors such as age.

STUDY DESIGN

Monte Carlo simulation model.

SETTING & POPULATION

Patients with chronic kidney disease, referred to a multidisciplinary kidney clinic in a universal health care system.

MODEL, PERSPECTIVE, & TIMEFRAME

Cost-effectiveness analysis, payer perspective, lifetime horizon.

INTERVENTION

The following vascular access referral policies are considered: central venous catheter (CVC) only, arteriovenous fistula (AVF) or graft (AVG) referral upon HD initiation, AVF (or AVG) referral when HD is forecast to begin within 12 (or 3 for AVG) months, AVF (or AVG) referral when estimated glomerular filtration rate is <15 (or <10 for AVG) mL/min/1.73m².

OUTCOMES

Incremental cost-effectiveness ratios (ICERs, in 2014 US dollars per quality-adjusted life-year [QALY] gained).

RESULTS

The ICER of AVF (AVG) referral within 12 (3) months of forecasted HD initiation, compared to using only a CVC, is ∼$105k/QALY ($101k/QALY) at a population level (HD costs included). Pre-HD AVF or AVG referral dominates delaying referral until HD initiation. The ICER of pre-HD referral increases with patient age. Results are most sensitive to erythropoietin costs, ongoing HD costs, and patients' utilities for HD. When ongoing HD costs are excluded from the analysis, pre-HD AVF dominates both pre-HD AVG and CVC-only policies.

LIMITATIONS

Literature-based estimates for HD, AVF, and AVG utilities are limited.

CONCLUSIONS

The cost-effectiveness of vascular access referral is largely driven by the annual costs of HD, erythropoietin costs, and access-specific utilities. Further research is needed in the field of dialysis-related quality of life to inform decision making regarding vascular access referral.

Clinical use of computational modeling for surgical planning of arteriovenous fistula for hemodialysis

BACKGROUND

Autogenous arteriovenous fistula (AVF) is the best vascular access (VA) for hemodialysis, but its creation is still a critical procedure. Physical examination, vascular mapping and doppler ultrasound (DUS) evaluation are recommended for AVF planning, but they can not provide direct indication on AVF outcome. We recently developed and validated in a clinical trial a patient-specific computational model to predict pre-operatively the blood flow volume (BFV) in AVF for different surgical configuration on the basis of demographic, clinical and DUS data. In the present investigation we tested power of prediction and usability of the computational model in routine clinical setting.

METHODS

We developed a web-based system (AVF.SIM) that integrates the computational model in a single procedure, including data collection and transfer, simulation management and data storage. A usability test on observational data was designed to compare predicted vs. measured BFV and evaluate the acceptance of the system in the clinical setting. Six Italian nephrology units were involved in the evaluation for a 6-month period that included all incident dialysis patients with indication for AVF surgery.

RESULTS

Out of the 74 patients, complete data from 60 patients were included in the final dataset. Predicted brachial BFV at 40 days after surgery showed a good correlation with measured values (in average 787 ± 306 vs. 751 ± 267 mL/min, R = 0.81, p < 0.001). For distal AVFs the mean difference (±SD) between predicted vs. measured BFV was -2.0 ± 20.9%, with 50% of predicted values in the range of 86-121% of measured BFV. Feedbacks provided by clinicians indicate that AVF.SIM is easy to use and well accepted in clinical routine, with limited additional workload.

CONCLUSIONS

Clinical use of computational modeling for AVF surgical planning can help the surgeon to select the best surgical strategy, reducing AVF early failures and complications. This approach allows individualization of VA care, with the aim to reduce the costs associated with VA dysfunction, and to improve AVF clinical outcome.

Vascular access conversion and patient outcome after hemodialysis initiation with a nonfunctional arteriovenous access: a prospective registry-based study

BACKGROUND

Little is known about vascular access conversion and outcomes for patients starting hemodialysis with nonfunctional arteriovenous (AV) access. We assessed mortality risk associated with nonfunctional AV access at hemodialysis initiation, taking subsequent changes in vascular access into account.

METHODS

We studied the 53,092 incident adult hemodialysis patients included in the French REIN registry from 2005 through 2012. AV access placed predialysis was considered nonfunctional when dialysis began with a central venous catheter. Information about vascular access changes was obtained from treatment modality updates.

RESULTS

At hemodialysis initiation, AV access was functional for 47% of patients and nonfunctional for 9%; 44% had a catheter alone. After a 3-year follow-up, 63% of patients beginning hemodialysis with a nonfunctional AV access had changed to a functional one, 4% had had a transplant, 19% had died before any vascular access change, and 13% still used a catheter. Cox proportional hazard models with vascular access treated as a time-dependent variable showed an adjusted mortality hazard ratio (95% confidence interval) for patients with nonfunctional AV access who subsequently converted to functional access of 0.95 (95% CI 0.89-1.03) compared with the reference group with functional AV access since first hemodialysis, versus 1.43 (95% CI 1.31-1.55) for those who did not convert.

CONCLUSIONS

Among patients starting hemodialysis with a nonfunctional AV access, a substantial percentage may never experience successful vascular access conversion. Poor survival seems to be limited to these patients, while those who subsequently convert to functional AV access have similar mortality risk compared to patients with such access since hemodialysis initiation. Every effort should be made to obtain functional AV access in all suitable patients.

A Systematic Review and Meta-Analysis of Circulating Biomarkers Associated with Failure of Arteriovenous Fistulae for Haemodialysis

BACKGROUND

Arteriovenous fistula (AVF) failure is a significant cause of morbidity and expense in patients on maintenance haemodialysis (HD). Circulating biomarkers could be valuable in detecting patients at risk of AVF failure and may identify targets to improve AVF outcome. Currently there is little consensus on the relationship between circulating biomarkers and AVF failure. The aim of this systematic review was to identify circulating biomarkers associated with AVF failure.

METHODS

Studies evaluating the association between circulating biomarkers and the presence or risk of AVF failure were systematically identified from the MEDLINE, EMBASE and Cochrane Library databases. No restrictions on the type of study were imposed. Concentrations of circulating biomarkers of routine HD patients with and without AVF failure were recorded and meta-analyses were performed on biomarkers that were assessed in three or more studies with a composite population of at least 100 participants. Biomarker concentrations were synthesized into inverse-variance random-effects models to calculate standardized mean differences (SMD) and 95% confidence intervals (CI).

RESULTS

Thirteen studies comprising a combined population of 1512 participants were included after screening 2835 unique abstracts. These studies collectively investigated 48 biomarkers, predominantly circulating molecules which were assessed as part of routine clinical care. Meta-analysis was performed on twelve eligible biomarkers. No significant association between any of the assessed biomarkers and AVF failure was observed.

CONCLUSION

This paper is the first systematic review of biomarkers associated with AVF failure. Our results suggest that blood markers currently assessed do not identify an at-risk AVF. Further, rigorously designed studies assessing biological plausible biomarkers are needed to clarify whether assessment of circulating markers can be of any clinical value. PROSPERO registration number CRD42016033845.

In Quality We Trust; but Quality of Life or Quality of Care?

The ESRD program provides medical care to a diverse and medically complex patient population. The care for the ESRD patient population has become increasingly benchmarked with process of care measures. These measures include dialysis adequacy, anemia, nutrition, and vascular access outcomes. These process-related dialysis measures may not improve the care of the individual patient as care relates to the individual's goals and values. There is also evidence that these process measures may not be causally related to quality of life, hospitalization, and survival. The adoption of patient-reported outcomes may shift the balance toward more patient-centered care. However, the extent to which mandated measures of health-related quality of life and patient satisfaction result in improved outcomes remains unclear.