Assessment of Use of Arteriovenous Graft vs Arteriovenous Fistula for First-time Permanent Hemodialysis Access

Importance

Initial hemodialysis access with arteriovenous fistula (AVF) is associated with superior clinical outcomes compared with arteriovenous graft (AVG) and should be the procedure of choice whenever possible. To address the national underuse of AVF in the United States, the Centers for Medicare & Medicaid has established an AVF goal of 66% or greater in 2009.

Objective

To explore contemporary practice patterns and physician characteristics associated with high AVG use compared with AVF use.

Design, Setting, and Participants

This review of 100% Medicare Carrier claims between January 1, 2016, and December 31, 2017, includes both inpatient and outpatient Medicare claims data. All patients undergoing initial permanent hemodialysis access placement with an AVF or AVG were included. All surgeons performing more than 10 hemodialysis access procedures during the study period were analyzed.

Exposures

Placement of an AVF or AVG for initial permanent hemodialysis access.

Main Outcomes and Measures

A surgeon-level AVG (vs AVF) use rate was calculated for all included surgeons. Hierarchical logistic regression modeling was used to identify patient-level and surgeon-level factors associated with AVG use.

Results

A total of 85 320 patients (median age, 70 [range, 18-103] years; 47 370 men [55.5%]) underwent first-time hemodialysis access placement, of whom 66 489 (77.9%) had an AVF and 18 831 (22.1%) had an AVG. Among the 2397 surgeons who performed more than 10 procedures per year, the median surgeon level AVG use rate was 18.2% (range, 0.0%-96.4%). However, 498 surgeons (20.8%) had an AVG use rate greater than 34%. After accounting for patient characteristics, surgeon factors that were independently associated with AVG use included more than 30 years of clinical practice (vs 21-30 years; odds ratio, 0.85 [95% CI, 0.75-0.96]), metropolitan setting (odds ratio, 1.25 [95% CI, 1.02-1.54]), and vascular surgery specialty (vs general surgery; odds ratio, 0.77 [95% CI, 0.69-0.86]). Surgeons in the Northeast region had the lowest rate of AVG use (vs the South; odds ratio, 0.83 [95% CI, 0.73-0.96]). First-time hemodialysis access benchmarking reports for individual surgeons were created for potential distribution.

Conclusions and Relevance

In this study, one-fifth of surgeons had an AVG use rate above the recommended best practices guideline of 34%. Although some of these differences may be explained by patient referral practices, sharing benchmarked performance data with surgeons could be an actionable step in achieving more high-value care in hemodialysis access surgery.

Can feedback approaches reduce unwarranted clinical variation? A systematic rapid evidence synthesis

Background

Assessment of clinical variation has attracted increasing interest in health systems internationally due to growing awareness about better value and appropriate health care as a mechanism for enhancing efficient, effective and timely care. Feedback using administrative databases to provide benchmarking data has been utilised in several countries to explore clinical care variation and to enhance guideline adherent care. Whilst methods for detecting variation are well-established, methods for determining variation that is unwarranted and addressing this are strongly debated. This study aimed to synthesize published evidence of the use of feedback approaches to address unwarranted clinical variation (UCV).

Methods

A rapid review and narrative evidence synthesis was undertaken as a policy-focused review to understand how feedback approaches have been applied to address UCV specifically. Key words, synonyms and subject headings were used to search the major electronic databases Medline and PubMed between 2000 and 2018. Titles and abstracts of publications were screened by two reviewers and independently checked by a third reviewer. Full text articles were screened against the eligibility criteria. Key findings were extracted and integrated in a narrative synthesis.

Results

Feedback approaches that occurred over a duration of 1 month to 9 years to address clinical variation emerged from 27 publications with quantitative (20), theoretical/conceptual/descriptive work (4) and mixed or multi-method studies (3). Approaches ranged from presenting evidence to individuals, teams and organisations, to providing facilitated tailored feedback supported by a process of ongoing dialogue to enable change. Feedback approaches identified primarily focused on changing clinician decision-making and behaviour. Providing feedback to clinicians was identified, in a range of a settings, as associated with changes in variation such as reducing overuse of tests and treatments, reducing variations in optimal patient clinical outcomes and increasing guideline or protocol adherence.

Conclusions

The review findings suggest value in the use of feedback approaches to respond to clinical variation and understand when action is warranted. Evaluation of the effectiveness of particular feedback approaches is now required to determine if there is an optimal approach to create change where needed.

Successful AV Fistula Creation does not Lead to Higher Catheter Use: The Experience by the Northwest Renal Network 16 Vascular access Quality Improvement Program. Four Years follow-up

Background

In 2002, the Center for Medicare and Medicaid Services (CMS) required all 18 Renal Networks to participate in a Vascular Access Quality Improvement Program (QIP). The Northwest Renal Network (NWRN 16) chose to increase arteriovenous fistula (AVF) use. NWRN 16 hypothesized that strategies which targeted the improvement of AVF rate and the reduction of catheter use were the same. In December 2001, 44.2% of hemodialysis (HD) patients in the NWRN 16 received HD using an AVF which met the Dialysis Outcome Quality Initiative (K/DOQI) 40% AVF guideline for prevalent patients. However, 43% of HD facilities (2869 patients) had less than 40% of AVF and higher HD catheter rates than the average Network catheter rates (25.0 vs. 20.3%). To address the needs of underperforming facilities, NWRN 16 provided education and tools for their vascular access decision makers to promote AVF creation and catheter reduction.

Methods

In 2002, NWRN 16 sponsored four regional workshops targeted at nephrologists, vascular surgeons, HD nurses, and interventional radiologists.

Results

Percentage of AVFs in use in invited facilities increased from 31.3% pre-intervention to 56.2% at 4 yrs: 78% increase (99% confidence interval: 77.8% to 81.5%). Percentage of catheters increased from 25% to 25.8%: 3.2% change over 4 yrs (99% confidence interval: 2.5% to 4%).

Conclusion

The success of Network 16's AVF interventions demonstrates the effectiveness of Network education promoting multidisciplinary teamwork, and innovative strategies to increase dramatically AVF use without substantial increase in catheter use.

Prosthetic Arteriovenous Grafts for Hemodialysis

Introduction

Prosthetic arteriovenous (AV) grafts are indicated in patients with failed AV fistula (AVF), exhausted superficial veins or unsuitable vessels. Increasing the proportion of prevalent hemodialysis (HD) patients using autogenous AVF should reduce the need for AV grafts and associated morbidity. This paper reviews the current role of prosthetic AV grafts in vascular access for HD.

Technical considerations

Prior to the insertion of a prosthetic AV graft, a comprehensive review of previous access procedures and full physical examination in addition to vessel mapping is required. Anastomotic technique should take into account the flow diffuser concept, graft geometry and an anastomotic angle of 15° in order to reduce the incidence of intimal hyperplasia.

Results

Many authors report 1 and 2-yr cumulative graft patency rates of 59–90% and 50–82%, respectively. The major drawbacks with synthetic grafts include: thrombosis, a five-fold increase in infection risk and steal syndrome. The choice between surgical and percutaneous methods of dealing with blocked AV grafts remains controversial, though percutaneous techniques are assuming an increasingly important role. Percutaneous strategies are successful in declotting access in 67–95% of cases. Stenting of stenotic lesions following thrombectomy improves secondary patency rates. Strategies for dealing with AV graft infection include antibiotic prophylaxis, partial, subtotal or total graft excision and the use of biological prosthesis.

Conclusions

Though more prone to complications than autogenous AVFs, AV grafts offer a short maturation period and are more amenable to thrombectomy by radiological or surgical means. Complex AV grafts may be appropriate in patients with exhausted access sites.

Clinical predictors of recurrent stenosis and need for re-intervention in the cephalic arch in patients with brachiocephalic AV fistulas

INTRODUCTION

Cephalic arch stenosis is one of the most common reasons for repeated endovascular intervention and eventual abandonment of access in hemodialysis patients. There is no prediction model to identify risk factors for recurrent cephalic arch stenosis. We have developed a mathematical model to predict the need for reintervention in brachiocephalic (BC) fistulas with recurrent cephalic arch stenosis.

METHODS

Single-center retrospective analysis of 143 patients with a BC fistula referred to the vascular clinic for access dysfunction who underwent cephalic arch angioplasty were included for the analysis. Twelve-month post-index angioplasty data were analyzed using parametric, non-parametric and multiple regression models using SPSS software.

RESULTS

The mean need for re-intervention in 1 year since first index visit was 2.46 ± 1.404. Statistically significant correlation (p≤0.001) for re-intervention was observed with the severity of stenosis at index visit, access flow, vessel wall diameter proximal to the stenosis, average venous pressure >50% of the delivered blood flow rate and prolonged bleeding for >30 minutes as a reason for referral. Three equations have been derived for calculating the need for re-intervention based on the diameter of the vessel wall proximal to the stenosis.

CONCLUSIONS

Risk stratification of BC fistulas utilizing the above parameters could enable clinicians to identify accesses that are at risk for multiple re-interventions. Early identification of accesses that are at high risk for re-interventions at the cephalic arch might prolong access survival and reduce the cost for intervention by utilizing alternate strategies.

Repeated mappings of arm veins by physical examination: role of nephrologists in the selection of suitable veins for AV fistula surgery

Multidisciplinary team work is important for a successful hemodialysis vascular access program. The authors present a clinical case to illustrate the potential dynamic factors that can affect vein sizes, independent from the operators' skills and experiences. Therefore, if the first examination fails to detect suitable veins, repeated examinations of arm veins by nephrologists during routine office visits may greatly assist the surgeons in the selection of suitable arm veins for arteriovenous fistula surgery.

Continuous quality improvement in nephrology: a systematic review

BACKGROUND

Continuous quality improvement (CQI) has been successfully applied in business and engineering for over 60 years. While using CQI techniques within nephrology has received increased attention, little is known about where, and with what measure of success, CQI can be attributed to improving outcomes within nephrology care. This is particularly important as payors' focus on value-based healthcare and reimbursement is tied to achieving quality improvement thresholds. We conducted a systematic review of CQI applications in nephrology.

METHODS

Studies were identified from PubMed, MEDLINE, Scopus, Web of Science, CINAHL, Google Scholar, ProQuest Dissertation Abstracts and sources of grey literature (i.e., available in print/electronic format but not controlled by commercial publishers) between January 1, 2004 and October 13, 2014. We developed a systematic evaluation protocol and pre-defined criteria for review. All citations were reviewed by two reviewers with disagreements resolved by consensus.

RESULTS

We initially identified 468 publications; 40 were excluded as duplicates or not available/not in English. An additional 352 did not meet criteria for full review due to: 1. Not meeting criteria for inclusion = 196 (e.g., reviews, news articles, editorials) 2. Not nephrology-specific = 153, 3. Only available as abstracts = 3. Of 76 publications meeting criteria for full review, the majority [45 (61%)] focused on ESRD care. 74% explicitly stated use of specific CQI tools in their methods. The highest number of publications in a given year occurred in 2011 with 12 (16%) articles. 89% of studies were found in biomedical and allied health journals and most studies were performed in North America (52%). Only one was randomized and controlled although not blinded.

CONCLUSIONS

Despite calls for healthcare reform and funding to inspire innovative research, we found few high quality studies either rigorously evaluating the use of CQI in nephrology or reporting best practices. More rigorous research is needed to assess the mechanisms and attributes by which CQI impacts outcomes before there is further promotion of its use for improvement and reimbursement purposes.

Translating knowledge on best practice into improving quality of RRT care: a systematic review of implementation strategies

Recent studies showed wide variation in the extent to which guidelines and other types of best practice have been implemented as part of routine health care. This is also true for the delivery of renal replacement therapy (RRT) for ESRD patients. Increasing uptake of best practice within such complex care systems requires an understanding of implementation strategies and specific quality improvement (QI) techniques. Therefore, we systematically reviewed over 5000 titles published since 1990 and included papers describing planned attempts to accelerate uptake of best RRT practice into daily care. This resulted in a list of 93 QI initiatives, categorized in order to expedite shared learning. The majority of the initiatives were executed within the domains of vascular access, nutrition, and anemia management. Strategies oriented at patients were most common and many initiatives pre-defined an improvement target before starting implementation. Of the 93 initiatives, 22 were sufficiently robust methodologically to be analyzed in more detail. Our results tend to support previous findings that multifaceted strategies are more effective than single strategies. Improving our understanding of how to successfully implement best practice can inform system-level change and is the only way to close the gap between knowledge on what works and the actual care delivered to ESRD patients. Research into implementation, using specific QI techniques, should therefore be given priority in future.