The effect of implementation of an optimized care protocol on the outcome of arteriovenous hemodialysis access surgery

Comparison of Helical Interwoven Nitinol Stent Placement Versus Balloon Angioplasty for Arteriovenous Dialysis Graft Malfunction Caused by Stenosis of the Venous Anastomosis Site

Purpose

The study aimed to compare the differences in patency between helical interwoven nitinol stents and balloon angioplasty in patients with arteriovenous graft (AVG) malfunction caused by venous anastomosis stenosis.

Materials and Methods

This retrospective study included patients who underwent helical interwoven nitinol stent placement (n = 15) or balloon angioplasty (n = 25) between January 2016 and September 2021. The primary and secondary patency rates were compared between the two groups.

Results

Dialysis was possible post-intervention in all patients who showed no specific complications, including stent fracture. The average primary patency of the stent placement group was longer than that of the balloon angioplasty group but did not differ significantly (8.5 vs. 6.3 months, p = 0.319). The mean secondary patency period was 17.6 months in the stent placement group, which was shorter than that in the balloon angioplasty group (18.8 months); however, this difference was also not statistically significant (p = 0.660).

Conclusion

Helical interwoven nitinol stents could maintain patency in patients with AVG malfunction caused by venous anastomosis stenosis, but they did not improve patency compared to balloon angioplasty.

Primary Patency Success of Arteriovenous Shunts in Hemodialysis Patients: A 28-Month Prospective Study

Background Arteriovenous (AV) shunts are vital for providing long-term vascular access in hemodialysis patients. While brachiocephalic and radiocephalic shunts are commonly employed, data on their primary patency rates and associated complications in resource-limited settings such as Yemen remain scarce. This study aimed to evaluate the primary patency success of AV shunts and identify factors influencing their outcomes in hemodialysis patients at Al-Thawra Modern General Hospital. Methods This prospective observational study was conducted over 28 months, from April 2021 to August 2023, at Al-Thawra Modern General Hospital in Sana'a, Yemen. A total of 163 patients with chronic renal failure requiring AV shunt creation for hemodialysis were included. Data on patient demographics, comorbidities, shunt characteristics, and postoperative outcomes were collected. Primary patency was assessed at the 8-month follow-up interval. Statistical analysis was performed to identify factors associated with shunt patency. Results Among the enrolled 163 patients, the median age was 43.12 years, with 61.3% undergoing brachiocephalic shunt creation. The overall primary patency rate at 8 months was 87.7%, with brachiocephalic shunts exhibiting a significantly greater patency rate (93.0%) than radiocephalic shunts (67.3%) (p = 0.02). Complications occurred in 25% of patients, with pseudoaneurysm formation being the most common complication (6.1%). Factors such as shunt type, patient age, and comorbidities (e.g., diabetes) significantly influence patency outcomes. Conclusion Compared with radiocephalic shunts, brachiocephalic shunts demonstrated superior primary patency rates, suggesting that they may be a preferable option for long-term hemodialysis access in the studied population. These findings emphasize the need for individualized patient management and careful postoperative monitoring, particularly in resource-limited settings such as Yemen, to optimize AV shunt outcomes.

Protocol for a qualitative study exploring haemodialysis dependent patients' arteriovenous fistula experience, values and concerns in Sydney, Australia

INTRODUCTION

The experiences of patients from culturally and linguistically diverse backgrounds, with chronic mental illness, disabilities or who identify as sexual or religious minorities are under-represented in clinical research on arteriovenous fistula (AVF) for haemodialysis access. A greater understanding of the experiences, values and concerns of these diverse patient groups are needed to provide haemodialysis access care that addresses the needs of all haemodialysis-dependent patients. This study seeks to describe a broad range of patient experiences related to the creation, care and surveillance of AVFs, including interactions with healthcare teams.

METHODS AND ANALYSIS

This qualitative study will use semistructured interviews with individual patients purposefully selected to provide a diverse patient population. A deliberate strategy will be used to recruit a demographically broad range of participants. Thematic analysis of interview transcripts, using a constant comparative methodology, will generate themes that describe patient experiences, values and concerns. Findings from this study will give a nuanced insight into the experiences of patients on haemodialysis with respect to their AVF.

ETHICS AND DISSEMINATION

Ethical approval for this study was provided by the Sydney Local Health District Human Research Ethics Committee (REGIS identifier: 2021/ETH00362, CH reference number: CH62/6/2021-033). Results will be made available to the participants, local health district, funders and other researchers through various hospital and academic forums. Data will also be published in peer-reviewed journals and be part of a larger body of work looking into patient-reported outcome measures for patients with AVF.

Expert consensus on the establishment and maintenance of native arteriovenous fistula

Vascular access is the lifeline of hemodialysis patients. There are great differences in the establishment and use of vascular access in different countries and regions around the world. We believe that on the basis of good evaluation and planning, it is recommended that hemodialysis patients choose native arteriovenous fistula first. In view of the new progress of vascular access views domestic and international at home and abroad in recent years, we organized experts to recommend the establishment and maintenance of arteriovenous fistula (AVF) for the Chinese population, including preoperative evaluation and planning of the establishment of AVF, AVF surgery, perioperative drug intervention measures and postoperative maintenance, and put forward suggestions for future research directions. The recommendations in this consensus are general and clinicians need to make treatment decisions based on the actual situation.

Are continued policies of prioritizing native vascular access in patients on hemodialysis programs useful?

The guidelines recommend establishing native vascular access as opposed to prosthetic or catheter-based access despite information relating to its effectiveness being scarce from a patient-orientated perspective. We analyzed the effectiveness of a continued policy of native vascular access (CPNVA) in patients undergoing hemodialysis. A retrospective, observational study, including 150 patients undergoing hemodialysis between 2006 and 2012 at our center, and who underwent a CPNVA. Statistical analysis was based on treatment intention. In 138 patients (92%), the first useful access (FUA) was native, and in 12 patients (8%), it was prosthetic. In 50 patients (33.3%), more than one procedure had to be carried out in to order to achieve FUA. The probability of dialysis occurring via a FUA was 67.1% and 45.3% at 1 and 5 years respectively. Over the follow-up period (mean time = 30 months), 84 patients (56%) required repairs or new access, extending the effectiveness of the CPNVA to 88.3% and 73.2% at 1 and 5 years respectively. The effectiveness of the CPNVA was reduced if the patient: required a catheter initially (HR: 3.6, p = 0.007); in cases of initially elevated glomerular filtration rate (HR: 1.1, p = 0.040); in cases of history of previous access failure before FUA (HR: 3.9, p = 0.001); and in female patients (HR: 2.4, p = 0.031). The long-term effectiveness of a CPNVA is high. However, the percentage of patients requiring diverse procedures in order to achieve FUA and the need for re-interventions yield the necessity to optimize preoperative evaluation and postoperative follow-up.

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.

Vascular access clinic results before and after implementing a multidisciplinary approach adding routine Doppler ultrasound

BACKGROUND

A multidisciplinary approach and Doppler ultrasound (DU) assessment for the creation and maintenance of arteriovenous fistulas (AVF) for haemodialysis can improve prevalence and patency. The aim of this study was to analyse the impact of a new multidisciplinary vascular access (VA) clinic with routine DU.

MATERIAL AND METHODS

We analysed the VA clinic results from 2014 and 2015, before and after the implementation of a multidisciplinary team protocol (vascular surgeon/nephrologist) with routine DU in preoperative mapping and prevalent AVF.

RESULTS

We analysed 345 and 364 patients from 2014 and 2015 respectively. The number of surgical interventions was similar in both periods (p=.289), with a trend towards an increase in preventive surgical repair of AVF in 2015 (17 vs. 29, p=.098). 155 vs. 169 new AVF were performed in 2014 and 2015, with a significantly lower primary failure rate in 2015 (26.4 vs. 15.3%, p=.015), and a non-significant increase in radiocephalic AVF, 25.8 vs. 33.2% (n=40 vs. 56), p=.159. The concordance between the indication at the clinic and the surgery performed also increased (81.3 vs. 93.5%, p=.001). Throughout 2015 fewer complementary imaging test were requested from the clinic (78 vs. 35, p <.001), with a corresponding reduction in costs (€87,716 vs. €59,445).

CONCLUSIONS

Multidisciplinary approach with routine DU can improve VA results, with a decrease in primary failure rate, higher likelihood of radiocephalic AVF, better management of dis-functioning AVF and lower radiological test costs.

Relationships Between Clinical Processes and Arteriovenous Fistula Cannulation and Maturation: A Multicenter Prospective Cohort Study

BACKGROUND

Half of surgically created arteriovenous fistulas (AVFs) require additional intervention to effectively support hemodialysis. Postoperative care and complications may affect clinical maturation.

STUDY DESIGN

Hemodialysis Fistula Maturation (HFM) Study, a 7-center prospective cohort study.

SETTING & PARTICIPANTS

491 patients with single-stage AVFs who had neither thrombosis nor AVF intervention before a 6-week postoperative ultrasonographic examination and who required maintenance hemodialysis.

PREDICTORS

Postoperative care processes and complications.

OUTCOMES

Attempted cannulation, successful cannulation, and unassisted and overall clinical maturation as defined by the HFM Study criteria.

RESULTS

AVF cannulation was attempted in 443 of 491 (90.2%) participants and was eventually successful in 430 of these 443 (97.1%) participants. 263 of these 430 (61.2%) reached unassisted and 118 (27.4%) reached assisted AVF maturation (overall maturation, 381/430 [88.6%]). Attempted cannulation was less likely in patients of surgeons with policies for routine 2-week versus later-than-2-week first postoperative visits (OR, 0.21; 95% CI, 0.06-0.70), routine second postoperative follow-up visits (OR, 0.39; 95% CI, 0.15-0.97), and a routine clinical postoperative ultrasound (OR, 0.28; 95% CI, 0.14-0.55). Attempted cannulation was also less likely among patients undergoing procedures to assist maturation (OR, 0.51; 95% CI, 0.27-0.98). Unassisted maturation was more likely for patients treated in facilities with access coordinators (OR, 1.91; 95% CI, 1.17-3.12), but less likely after precannulation nonstudy ultrasounds (OR per ultrasound, 0.42 [95% CI, 0.26-0.68]) and initial unsuccessful cannulation attempts (OR per each additional attempt, 0.90 [95% CI, 0.83-0.98]). Overall maturation was less likely with infiltration before successful cannulation (OR, 0.44; 95% CI, 0.22-0.89). Among participants receiving maintenance hemodialysis before AVF surgery, unassisted and overall maturation were less likely with longer intervals from surgery to initial cannulation (ORs for each additional month of 0.81 [95% CI, 0.76-0.88] and 0.93 [95% CI, 0.89-0.98], respectively) and from initial to successful cannulation (ORs for each additional week of 0.87 [95% CI, 0.81-0.94] and 0.88 [95% CI, 0.83-0.94], respectively).

LIMITATIONS

Surgeons' management policies were assessed only by questionnaire at study onset. Most participants received upper-arm AVFs, planned 2-stage AVFs were excluded, and maturation time windows were imposed. Some care processes may have been missed and the observational design limits causal attribution.

CONCLUSIONS

Multiple processes of care and complications are associated with AVF maturation outcomes.

A Review of Percutaneous Transluminal Angioplasty in Hemodialysis Fistula

The number of patients in dialysis increases every year. In this review, we will evaluate the role of percutaneous transluminal angioplasty (PTA) according to patency of arteriovenous fistula and grafts. The main indication of PΤΑ is stenosis > 50% or obstruction of the vascular lumen of an arteriovenous fistula and graft. It is usually performed under local anesthesia. The infection rate is as low as the number of complications. Fistula can be used in dialysis in the same day without the need for a central venous catheter. Primary patency is >50% in the first year while primary assisted patency is 80-90% in the same time period. Repeated PTA is as durable as the primary PTA. An early PTA carries a risk of new interventions. Cutting balloon can be used as a second-line method. Stents and covered stents are kept for the management of complications and central outflow venous stenosis. PTA is the treatment of choice for stenosis or obstruction of dialysis fistulas. Repeated PTA may be needed for better patency. Drug eluting balloon may become the future in PTA of dialysis fistula, but more trials are needed.

Introduction of arteriovenous grafts with graft insertion anastomosis for hemodialysis access

OBJECTIVE

An arteriovenous bridging graft is a viable option for patients with compromised arteries or veins because of advanced age or diabetes. Arteriovenous graft with graft insertion anastomosis (AVGI) is the novel technique for graft-vein anastomosis where the prosthesis is inserted into the vein, and the anastomosis is performed on the surface of the prosthesis. This study assessed the short-term and long-term results of AVGI to clarify the efficacy of this technique.

METHODS

Between 2010 and 2015, AVGI was performed in graft-vein anastomosis of prosthetic forearm loop access. Characteristics and level of complications were assessed. To evaluate the long-term results, functional graft patency and frequency of percutaneous transluminal angioplasty were examined.

RESULTS

The study comprised 58 patients. There were no deaths related to the surgery. The time of hemostasis after AVGI was recorded at 0 seconds because no bleeding from the suture holes was seen. At 1, 2, and 3 years, primary patency were 45.1% ± 7.5%, 23.1% ± 7.5%, and 23.1% ± 7.5%, respectively, and assisted primary patency rates were 59.4% ± 7.2%, 50.8% ± 7.6%, and 50.8% ± 7.6%, respectively. Secondary patency rates at 4 and 5 years were 100% ± 0% and 94.1% ± 5.7%, respectively. The frequency of percutaneous balloon angioplasty to maintain the patency was 1.61 ± 0.53 times per year. Graft infection occurred in four patients (6.9%).

CONCLUSIONS

AVGI is an advantageous technique for graft vein anastomosis in an arteriovenous bridging graft in both the short-term and long-term.

New Insights into Dialysis Vascular Access: What Is the Optimal Vascular Access Type and Timing of Access Creation in CKD and Dialysis Patients?

Optimal vascular access planning begins when the patient is in the predialysis stages of CKD. The choice of optimal vascular access for an individual patient and determining timing of access creation are dependent on a multitude of factors that can vary widely with each patient, including demographics, comorbidities, anatomy, and personal preferences. It is important to consider every patient's ESRD life plan (hence, their overall dialysis access life plan for every vascular access creation or placement). Optimal access type and timing of access creation are also influenced by factors external to the patient, such as surgeon experience and processes of care. In this review, we will discuss the key determinants in optimal access type and timing of access creation for upper extremity arteriovenous fistulas and grafts.

Venous aneurysm complicating arteriovenous fistula access and matrix metalloproteinases

Introduction

An arteriovenous fistula (AVF) for placed for hemodialysis may be burdened by one particular complication—the formation of a venous aneurysm. It has been shown that matrix metalloproteinases (MMPs) and neutrophil gelatinase-associated lipocalin (NGAL) could represent markers of disease in both venous and arterial vessels.

Materials and methods

This case study reports a rare case of enormous venous aneurysm-correlated MMP and NGAL levels in a woman with an AVF.

Results

Significantly higher levels of plasma MMP-1, MMP-8, MMP-9, and NGAL were detected in this patient during aneurysmal evaluation before the surgery; these levels significantly decreased 1, 3 and 6 months after surgery.

Conclusion

MMP and NGAL levels could represent a marker of aneurysmal disease, and their plasma evaluation could help physicians to stratify the risk of complications in patients with an AVF.

Preferred strategy for hemodialysis access creation in elderly patients

BACKGROUND

Adequate functioning vascular access is the key to successful hemodialysis. The use of an autologous arteriovenous fistula (AVF) is advised because of good long-term patency and a low incidence of complications. However, the number of patients with AVFs is declining because of the change in the demography of the dialysis population, with increasing numbers of very old patients with multiple comorbidities.

METHODS

In this vignette an elderly patient is described with calcified distal arteries and a small cephalic vein who is referred at a late stage for access creation. The results and performance of different types of vascular access (AVF; arteriovenous graft; central vein catheter), in relation to late referral and patient demographics, are described. In addition, patient morbidity and mortality versus the type of access are discussed.

CONCLUSIONS

The patient described in this vignette appears to be unsuitable for the creation of a forearm AVF because of calcified distal arteries and a small cephalic vein. The risk of non-maturing autologous AVFs is high in elderly patients and this observation might justify the use of early stick grafts. High risk patients may benefit from permanent central vein catheters.

Hemodialysis vascular access management in the Netherlands

PURPOSE

In the Netherlands, 86% of patients start renal replacement therapy with chronic intermittent hemodialysis (HD). Guidelines do indicate predialysis care and maintenance of a well-functioning vascular access (VA) as critical issues in the management of the renal failure patient. Referral to the surgeon and time to VA creation are important determinants of the type and success of the VA and HD treatment.

METHODS AND RESULTS

Data from a national questionnaire showed that time from referral to the surgeon and actual access creation is <4 weeks in 43%, 4 to 8 weeks in 30% and >8 weeks in 27% of the centers. Preoperative ultrasonography and postoperative access flowmetry are the diagnostic methods in the majority of centers (98%). Most facilities perform rope-ladder cannulation with occasionally the buttonhole technique for selected patients in 87% of the dialysis units. Endovascular intervention for thrombosis is practiced by 13%, surgical thrombectomy by 21% and either endovascular or surgery by 66% of the centers. Weekly multidisciplinary meetings are organized in 57% of the units. Central vein catheters are inserted by radiologists (36%), nephrologists and surgeons (32%).

CONCLUSIONS

We conclude that guidelines implementation has been successful in particular regarding issues as preoperative patient assessment for VA creation and postoperative surveillance in combination with (preemptive) endovascular intervention, leading to very acceptable VA thrombosis rates.

Outcomes of percutaneous interventions in transposed hemodialysis fistulas compared with nontransposed fistulas and grafts

PURPOSE

To compare postpercutaneous intervention outcomes of autogenous venous-transposition arteriovenous fistulas (AVFs) versus those of autogenous nontransposed AVFs (nAVFs) and prosthetic arteriovenous grafts (AVGs).

MATERIALS AND METHODS

A total of 591 hemodialysis accesses (195 transposed AVFs [tAVFs], 205 nAVFs, 191 AVGs) in 522 patients (278 male; mean age, 57 y; range, 15–91 y) underwent percutaneous transluminal angioplasty (PTA) and/or mechanical thrombectomy (ie, declotting). Access characteristics, surgical history, percutaneous interventions, postinterventional primary and secondary access patency, and follow-up data were collected. Cox proportional-hazards regression analyses, Fisher exact tests, and χ2 tests were performed.

RESULTS

Mean follow-up period was 32 months. Mean access ages at initial percutaneous intervention were 260 days (tAVF), 206 days (nAVF), and 176 days (AVG; P < .01). One-year postinterventional primary patency (PIPP) rates were 25% (tAVF), 24% (nAVF), and 14% (AVG). One-year postinterventional secondary patency (PISP) rates were 77% (tAVF), 61% (nAVF), and 63% (AVG). Median PIPP durations were 138 days (tAVF), 121 days (nAVF), and 79 days (AVG; P = .0001). Median PISP durations were 1,076 days (tAVF), 783 days (nAVF), and 750 days (AVG; P = .019). Total interventions needed to maintain PISP were 2.4 (tAVF), 1.3 (nAVF), and 3.2 (AVG) per patient-year (P < .001), which included 1.9, 1.2, and 1.4 PTAs (P < .01) and 0.45, 0.15, and 1.8 declotting procedures, respectively (P < .001).

CONCLUSIONS

Based on the number of percutaneous interventions needed to maintain PISP, these results confirm the current Dialysis Outcomes Quality Initiative access preference of nAVFs before tAVFs before AVGs. tAVFs offered superior postinterventional outcomes than AVGs. With additional interventions, tAVFs could even outperform nAVFs in terms of PISP.

Is Repeat PTA of a Failing Hemodialysis Fistula Durable?

Purpose. Our objective was to evaluate the outcome of percutaneous transluminal angioplasty (PTA) and particularly rePTA in a failing arteriovenous fistula (AV-fistula). Are multiple redilations worthwhile? Patients and Methods. All 159 stenoses of AV fistulas that were treated with PTA, with or without stenting, during 2008 and 2009, were included. Occluded fistulas that were dilated after successful thrombolysis were also included. Median age was 68 (interquartile range 61.5-78.5) years and 75% were male. Results. Seventy-nine (50%) of the primary PTAs required no further reintervention. The primary patency was 61% at 6 months and 42% at 12 months. Eighty (50%) of the stenoses needed at least one reintervention. Primary assisted patency (defined as patency after subsequent reinterventions) was 89% at 6 months and 85% at 12 months. The durability of repeated PTAs was similar to the durability of the primary PTA. However, an early primary PTA carried a higher risk for subsequent reinterventions. Successful dialysis was achieved after 98% of treatments. Nine percent of the stenoses eventually required surgical revision and 13% of the fistulas failed permanently. Conclusion. The present study suggests that most failing AV-fistulas can be salvaged endovascularly. Repeated PTA seems similarly durable as the primary PTA.

Natural history of upper limb arterio-venous fistulae for chronic hemodialysis

PURPOSE

Arterio-venous fistulae (AVF) for hemodialysis are prone to problems, ultimately leading to failure of the fistulae. Our aim was to determine the site and time to first stenosis and time to and factors influencing AVF failure for radio-cephalic (RC), brachio-cephalic (BC), and transposed brachio-basilic (BB) AVF.

METHODS

Retrospective analysis of native AVF constructed within a single vascular unit between January 2002-December 2008. Patients followed up to the end points of death, AVF failure or end of study period. Data collected included: age, sex, AVF type, time and site of first stenosis and time to failure. The relationship between fistula type, stenosis, and failure were examined.

RESULTS

In total, 398 native AVF were included in the study (91 RC, 208 BC, and 99 BB), with a mean age of 66 years. A total of 215 (54%) AVF developed a flow limiting stenosis, and over time 151 (40%) AVF failed. Stenoses developed significantly earlier in RC AVF (median 113 days) compared to BC (median 277 days), compared to BB (median days 414), P=.029. There was no statistically significant difference in time to failure (RC median 1344 days; BC median 1576 days; BB median 1159 days), P=.673. The presence of stenosis was the only variable found to have a significant impact on AVF failure in multivariate analysis.

CONCLUSIONS

Type of upper limb fistula did not impact on failure rates. Flow limiting stenoses impacted on fistula failure.

Indications for vascular grafts as hemodialysis access: consensus from experience in Italy

INTRODUCTION

In Italy, the use of arteriovenous grafts (AVG) is limited (1-5 %) due to different approaches to vascular access (VA) management as compared to other countries, where guidelines (which may not apply to the Italian setting) have been produced. Therefore, the Study Group (GdS) on VA of the Italian Society of Nephrology produced this position paper, providing a list of 8 recommendations built upon current guidelines.

METHODS

The most controversial and innovative issues of existing guidelines have been summed up in 12 different statements. We selected 60 Italian dialysis graft experts, nephrologists and vascular surgeons (PP1SIN Study Investigators). They were asked to express their agreement/disagreement on each issue, thus creating a new method to share and exchange information.

RESULTS

Most of them agreed (consensus > 90%) on specific criteria set to choose AVG over native AVF (nAVF) and tunnelled venous catheter (tVC) and on the necessary conditions to implant them. They did not fully agree on the use of AVG in obese patients, in patients at risk of developing ischemia, on the priority of AVG as an alternative to brachial-basilic fistula with vein transposition, and in case of a poorly organized setting regarding graft maintenance. Keeping in mind that the nAVF should be preferred whenever is feasible, AVGs are indicated when superficial veins are unavailable or to repair a nAVF (bridge graft). An AVG is an alternative to tVC if the expected patient survival is long enough to guarantee its clinical benefits.

Prevalence of arteriovenous fistulas in incident hemodialysis patients: correlation with patient factors that may be associated with maturation failure

BACKGROUND

Lok et al previously reported a risk equation for arteriovenous fistula (AVF) maturation failure. It is unclear whether this model or a more comprehensive model correlates with incident AVF use in the US hemodialysis population.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

195,756 adult patients initiating outpatient hemodialysis therapy in the United States between July 1, 2005, and December 31, 2009, with 6 months or more prior nephrology care.

PREDICTOR

Patient characteristics (age, peripheral vascular disease, coronary artery disease, and race) populating the AVF maturation failure risk equation and other demographic and clinical variables from the Centers for Medicare & Medicaid Services (CMS) Medical Evidence Report (CMS 2728).

OUTCOMES & MEASUREMENTS

AVF use at first outpatient dialysis treatment as recorded on the CMS 2728.

RESULTS

Using the risk categories defined by Lok et al, AVF use varied from 19.0% (very high risk) to 25.6% (low risk). In a model using only these risk categories, logistic regression showed lower ORs for moderate-, 0.90 (95% CI, 0.88-0.93); high-, 0.80 (95% CI, 0.78-0.83); and very high-risk patients, 0.68 (95% CI, 0.63-0.73) compared with low risk. In the expanded model, odds were lower for women, blacks, Hispanics, age older than 85 years, diabetes, peripheral vascular disease, congestive heart failure, other cardiac disease, and underweight. Odds were higher for hypertension, overweight, obesity, 12 months or more nephrologist care, most insurance types, and each successive year after 2005. Despite associations, the C statistic for the expanded model was 0.64.

LIMITATIONS

This analysis is limited by lack of access creation history before dialysis therapy initiation and minimal external validation of CMS 2728 data.

CONCLUSIONS

Clinical risk factors identified by Lok and expanded in this analysis have limited ability to predict incident AVF use. Even patients judged at highest risk can have successful AVF construction and initiate dialysis therapy through a functioning AVF.

Dialysis access in europe and north america: are we on the same path?

Large differences in dialysis access exist between Europe, Canada, and the United States, even after adjustment for patient characteristics. Vascular access care is characterized by similar issues, but with a different magnitude. Obesity, type 2 diabetes, and peripheral vascular disease, independent predictors of central venous catheter use, are growing problems globally, which could lead to more difficulties in native arteriovenous fistula placement and survival. Creation of dedicated dialysis access teams, including a vascular access coordinator, is a fundamental step in improving vascular access care; however, it might not be sufficient. The possibility that factors other than patient characteristics and surgical skills are important in determining outcomes is likely; it might explain apparent contradictions of end-stage renal disease (ESRD) practices (kidney transplant, peritoneal dialysis, patterns of vascular access use in hemodialysis), where some countries excel in one area and score poorly in another. We are on the same path, but we have a long way to go.

High rate of fistula placement in a cohort of dialysis patients in a single payer system

Arteriovenous fistulas (AVFs) are considered superior to arteriovenous grafts and catheters. Nevertheless, AVF prevalence in the United States remains under the established target. The complication rates and financial cost of vascular access continue to rise and disproportionately contribute to the burgeoning health care costs. The relationship between financial incentives for a type of vascular access and rate of access placement is unclear. All chronic hemodialysis patients (n=99) receiving care at Philadelphia Veterans Affairs Medical Center as of August 1, 2008 were participants. Demographic characteristics, vascular access type, and nonrelative value unit compensation were assessed as predictors, and the vascular access prevalence rate, operative times, and frequency of access interventions were analyzed. A 73.7% AVF rate was achieved in this cohort of patients with 51.5% diabetes mellitus. The number of access procedures per patient per year remained constant over time. The Philadelphia Veterans Affairs Medical Center, a single payer system, achieved superior AVF prevalence and exceeded the national AVF target. Financial incentives for arteriovenous graft placement currently exist in the United States, as there is similar Medicare reimbursement for arteriovenous graft and basilic vein transposition, despite longer operative times for basilic vein transpositions. The high AVF prevalence at the Philadelphia Veterans Affairs Medical Center may be due to the VA nonrelative value unit-driven system that allows for interdisciplinary care, priority of AVFs, and frequent use of basilic vein transposition surgery, when appropriate. We have identified an important, hypothesis-generating example of a nonrelative value unit-based approach to vascular access yielding superior results with respect to patient care and cost.

Arteriovenous fistulas among incident hemodialysis patients in Department of Defense and Veterans Affairs facilities

A higher proportion of patients initiate hemodialysis (HD) with an arteriovenous fistula (AVF) in countries with universal health care systems compared with the United States. Because federally sponsored national health care organizations in the United States, such as the Department of Veterans Affairs (DVA) and the Department of Defense (DoD), are similar to a universal health care model, we studied AVF use within these organizations. We used the US Renal Data System database to perform a cross-sectional analysis of patients who initiated HD between 2005 and 2006. Patients who received predialysis nephrology care had 10-fold greater odds of initiating dialysis with an AVF (adjusted odds ratio [aOR] 10.3; 95% confidence interval [CI] 9.6 to 11.1). DVA/DoD insurance also independently associated with initiating HD with an AVF (aOR 1.4; 95% CI 1.2 to 1.5). Fewer patients initiated HD at a DoD facility, but these patients were also approximately twice as likely to use an AVF (aOR 2.3; 95% CI 1.2 to 4.6). In conclusion, patients in DVA/DoD systems are significantly more likely to use an AVF at initiation of HD than patients with other insurance types, including Medicare. Further study of these federal systems may identify practices that could improve processes of care across health care systems to increase the number of patients who initiate HD with an AVF.

The use of a new kind of low profile retractor for arteriovenous fistula procedure simplifies and speeds up the intervention

PURPOSE

The aim of this study was to demonstrate the effectiveness of a new kind of disposable surgical retractor in arteriovenous fistula (AVF) procedures in order to achieve an easier, faster and safer surgical intervention.

METHODS

Between January and June 2008, 22 AVF procedures were performed using the 3PAWS ReeTrakt (Insightra Inc. - Irvine, Ca., USA) a self-retaining, low profile retractor. An equivalent patient sample, in which an AVF was performed using conventional retraction devices, was considered for comparison of the intra- and post-operative results.

RESULTS

In all of the 22 AVF procedures performed, the ReeTrakt system has simplified the performance of the surgical team. The retractors were very easy to place. The view of the operating field was always optimal. The introduction of the surgical instruments was at all times extremely easy and unrestricted. We also noted a reduction in the operating time (from an average of 67 min in controls to 43 min). There were no intra-operative complications. No post-operative complications related to the use of this kind of device occurred. Conversely, the amount of intra- and post-operative complications in the control group managed with conventional retraction devices was marginally higher than in the ReeTrakt patient group.

CONCLUSION

The ReeTrakt system is a very simple and useful low profile retractor for AVF procedures. Its ultra low profile allows a much improved view of the operating field, an unhindered insertion of the surgical instruments and a shortening of intervention time, avoiding the problems which arise as a result of standard retractors typically used during this kind of procedure. Due to absolute perpendicular retraction it offers a highly atraumatic performance, avoiding swelling and marks on the insertion sites. Therefore, in our opinion, it has the potential to reduce the risk of wound oedema, hematomas or infection associated with the AVF procedure. This is important as many patients are elderly with fragile tissues.