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Objective: Clinical guidelines provide recommendations on the minimal blood vessel diameters required for arteriovenous fistula creation but the evidence for these recommendations is limited. We compared vascular access outcomes of fistulas created in agreement with the ESVS Clinical Practice Guidelines (i.e. arteries and veins >2 mm for forearm fistulas and >3 mm for upper arm fistulas) with fistulas created outside these recommendations., Methods: The multicenter Shunt Simulation Study cohort contains 211 hemodialysis patients who received a first radiocephalic, brachiocephalic, or brachiobasilic fistula before publication of the ESVS Clinical Practice Guidelines. All patients had preoperative duplex ultrasound measurements according to a standardized protocol. Outcomes included duplex ultrasound findings at 6 weeks after surgery, vascular access function, and intervention rates until 1 year after surgery., Results: In 55% of patients, fistulas were created in agreement with the ESVS Clinical Practice Guidelines recommendations on minimal blood vessel diameters. Concordance with the guideline recommendations was more frequent for forearm fistulas than for upper arm fistulas (65% vs 46%, p  = 0.01). In the entire cohort, agreement with the guideline recommendations was not associated with an increased proportion of functional vascular accesses (70% vs 66% for fistulas created within and outside guideline recommendations, respectively; p  = 0.61) or with decreased access-related intervention rates (1.45 vs 1.68 per patient-year, p  = 0.20). In forearm fistulas, however, only 52% of arteriovenous fistulas created outside these recommendations developed into a timely functional vascular access., Conclusions: Whereas upper arm arteriovenous fistulas with preoperative blood vessel diameters <3 mm had similar vascular access function as fistulas created with larger blood vessels, forearm arteriovenous fistulas with preoperative blood vessel diameters <2 mm had poor clinical outcomes. These results support that clinical decision-making should be guided by an individual approach., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The growing number of prevalent arteriovenous (AV) accesses has been associated with an increase in the incidence of procedures being performed to maintain patency. To reduce the rate of unnecessary procedures, the 2019 Kidney Disease Outcome Quality Initiative guidelines addended the AV access surveillance recommendations, which includes clinical monitoring and assessment of dialysis adequacy alone. Abnormal clinical findings would necessitate follow-up angiography with or without confirmatory duplex ultrasound. Due to poor patency, increased surveillance schedules have been proposed to identify stenosis early and potentially prevent acute thrombotic events and AV access failure. In this review, we outlined current AV access monitoring and maintenance procedure recommendations, as described by the Centers for Medicare and Medicaid Services and 2019 Kidney Disease Outcome Quality Initiative guidelines. In addition, we highlight the findings of recently published randomized controlled trials that have examined increased surveillance schedules., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Arteriovenous grafts are routinely placed to facilitate hemodialysis in patients with end stage renal disease. These grafts are conduits between higher pressure arteries and lower pressure veins. The connection on the vein end of the graft, known as the graft-to-vein anastomosis, fails frequently and chronically due to high rates of stenosis and thrombosis. These failures are widely believed to be associated with pathologically high and low flow shear strain rates at the graft-to-vein anastomosis. We hypothesized that consistent with pipe flow dynamics and prior work exploring vein-to-artery anastomosis angles in arteriovenous fistulas, altering the graft-to-vein anastomosis angle can reduce the incidence of pathological shear rate fields. We tested this via computational fluid dynamic simulations of idealized arteriovenous grafts, using the Bird-Carreau constitutive law for blood. We observed that low graft-to-vein anastomosis angles ([Formula: see text]) led to increased incidence of pathologically low shear rates, and that high graft-to-vein anastomosis angles ([Formula: see text]) led to increased incidence of pathologically high shear rates. Optimizations predicted that an intermediate  ([Formula: see text]) graft-to-anastomosis angle was optimal. Our study demonstrates that graft-to-vein anastomosis angles can significantly impact pathological flow fields, and can be optimized to substantially improve arteriovenous graft patency rates.

Cannulation is essential for haemodialysis with arteriovenous access, but also damages the arteriovenous access making it prone to failure, is associated with complications and affects patients' experiences of haemodialysis. Managing Access by Generating Improvements in Cannulation is a national UK quality improvement project, designed to improve cannulation practice in the United Kingdom, ensuring it reflects current needling recommendations. It uses a simple quality improvement method, the Model for Improvement, to structure improvement to cannulation practice. It assists units in the practical implementation of the British Renal Society and Vascular Access Society of Britain and Ireland needling recommendations, ensuring actual cannulation practice reflects what is defined as best practice in cannulation. An eLearning package and awareness materials have been developed, to assist units in changing their cannulation practice. The Kidney Quality Improvement Partnership provides a structure for Managing Access by Generating Improvements in Cannulation that promotes development and dissemination. It is hoped that Managing Access by Generating Improvements in Cannulation will raise an understanding about the cannulation of arteriovenous access and change behaviours and beliefs around correct cannulation practice, to ensure longevity of this lifeline.

The COVID-19 pandemic has resulted in major disruption to the delivery of both routine and urgent healthcare needs in many institutions across the globe. Vascular access (VA) for haemodalysis (HD) is considered the patient's lifeline and its maintenance is essential for the continuation of a life saving treatment. Prior to the COVID-19 pandemic, the provision of VA for dialysis was already constrained. Throughout the pandemic, inevitably, many patients with chronic kidney disease (CKD) have not received timely intervention for VA care. This could have a detrimental impact on dialysis patient outcomes in the near future and needs to be addressed urgently. Many societies have issued prioritisation to allow rationing based on clinical risk, mainly according to estimated urgency and need for treatment. The recommendations recently proposed by the European and American Vascular Societies in the COVID-19 pandemic era regarding the triage of various vascular operations into urgent, emergent and elective are debatable. VA creation and interventions maintain the lifeline of complex HD patients, and the indication for surgery and other interventions warrants patient-specific clinical judgement and pathways. Keeping the use of central venous catheters at a minimum, with the goal of creating the right access, in the right patient, at the right time, and for the right reasons, is mandatory. These strategies may require local modifications. Risk assessments may need specific "renal pathways" to be developed rather than applying standard surgical risk stratification. In conclusion, in order to recover from the second wave of COVID-19 and prepare for further phases, the provision of the best dialysis access, including peritoneal dialysis, will require working closely with the multidisciplinary team involved in the assessment, creation, cannulation, surveillance, maintenance, and salvage of definitive access.

Improved quality of surgical procedures can minimize complications, the morbidity and mortality of patients, and in addition decrease costs. Quality indicators in angioaccess surgery are, however, not clearly defined. The aim of this review article is therefore to find the most important factors affecting quality in vascular access procedures. Even though autogenous arteriovenous fistula has been recognized as the best vascular access for hemodialysis, the high percentage of unsuccessful attempts associated with it raises the question about quality assessment in angioaccess procedures. Unfortunately, quality indicators in vascular access surgery are difficult to define and measure. Among those that can be obtained are: the time between the presentation of patients to a vascular access surgeon and the construction of a fistula, the percentage of autogenous fistulas, the percentage of functional fistulas in prevalent and incident hemodialysis patients, the percentage of creation of a functional fistula in the first attempt, and durability of an access. Organizational improvement and educational programs are also necessary at institutions with inferior quality indicators of vascular access care, as even small increase in quality may mean the survival of an individual patient. Quality indicators in angioaccess surgery can also serve as a helpful tool in choosing the best vascular access surgeon or vascular access center. The choice can consequently reflect on increased survival and quality of life in patients needing hemodialysis.

Majority of the chronic kidney disease (CKD) patients undergo hemodialysis (HD) with central venous catheter which has multiple complications. This study aims to identify the physicians' perspectives regarding the reasons of delayed arteriovenous fistula (AVF) creation in the Kingdom of Saudi Arabia to improve the quality of CKD patients' care and prognosis and prevent complications. A cross-sectional descriptive study was conducted on KSA nephrologists using a questionnaire which includes factors associated with delay in AVF creation, which were categorized into patient, physician, and hospital factors. The optimal timing of starting dialysis was also assessed. In a total of 212 participants, 131 (61.8%) were of consultant level, with the largest numbers being from the Central region (52.4%). The most important patient factors associated with delay in AVF creation were denial of kidney disease or the need of AVF (76.4%), dialysis fears and practical concern (75.9%), and patient refusal (73.1%). The most important physician and hospital factors were insufficient conduction of predialysis care and education (63.7%) and late referral to a nephrologist (56.6%). Participants would create AVF when the patient reaches Stage 4 CKD (69.3%) or Stage 5 (27.4%), and 88.7% of the participants would do so 3-6 months before the anticipated start of HD. Over two-thirds of the participants (68.4%) chose patient as the main factor contributing to the delay of permanent vascular access. A validated approach to patient selection, patient-centered predialysis care, and referral to vascular access creation that could be applied on different types of patients in different regions is required.

Vascular accesses for hemodialysis are considered the patient's lifeline and their maintenance is essential for treatment continuity. Following the example of institutions in other countries affected by the Covid-19 pandemic, the Brazilian Society of Nephrology developed these guidelines for healthcare services, elaborating on the importance of carrying out procedures for the preparation and preservation of vascular accesses. Creating definitive accesses for hemodialysis, grafts and arteriovenous fistulas are non-elective procedures, as well as the transition from the use of non-tunneled catheters to tunneled catheters, which cause less morbidity. In the case of patients with suspected or confirmed coronavirus infection, one may postpone the procedures for the quarantine period, to avoid spreading the disease.

Questo documento è stato tradotto dall'inglese a nome dell'ERBP (European Renal Best Practice), un organo ufficiale dell'ERA-EDTA (European Renal Association - European Dialysis and Transplant Association), e si basa su una pubblicazione ufficiale edita su Nephrology, Dialysis and Transplantation (NDT). ERBP si assume la piena responsabilità solo per la versione completa delle linee guida in originale e in lingua inglese pubblicate su NDT: Gallieni M, Hollenbeck M, Inston N, et al. Clinical practice guideline on peri- and postoperative care of arteriovenous fistulas and grafts for haemodialysis in adults. Nephrol Dial Transplant 2019; 34(S&#95;2):ii1-ii42. https://doi.org/10.1093/ndt/gfz072.

The nephrologist has a pivotal role as the leader of multidisciplinary teams to optimize vascular access care of the patient on dialysis and to promote multidisciplinary collaboration in research, training, and education. The continued success of interventional nephrology as an independent discipline depends on harnessing these efforts to advance knowledge and encourage innovation. A comprehensive curriculum that encompasses research from bench to bedside coupled with standardized clinical training protocols are fundamental to this expansion. As we find ourselves on the threshold of a much-awaited revolution in nephrology, there is great opportunity but also formidable challenges in the field - it is up to us to work together to realize the enormous potential of our discipline., (Copyright © 2020 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Quality assessment in vascular access procedures for hemodialysis is not clearly defined. The aim of this article is to compare various guidelines regarding recommendation on quality control in angioaccess surgery. The overall population of end-stage renal disease patients and patients in need for hemodialysis treatment is growing every year. Chronic intermittent hemodialysis is still the main therapy. The formation of a functional angioaccess is the cornerstone in the management of those patients. Native (autologous) arteriovenous fistula is the best vascular access available. A relatively high percentage of primary failure and fistula abandonment increases the need for quality control in this field of surgery. There are very few recommendations of quality assessment on creation of a vascular access for hemodialysis in the searched guidelines. Some guidelines recommend the proportion of native arteriovenous fistula in incident and prevalent patients as well as the maximum tolerable percentage of central venous catheters and complications. According to some guidelines, surgeon's experience and expertise have a considerable influence on outcomes. There are no specific recommendations regarding surgeon's specialty, grade, level of skills, and experience. In conclusion, there is a weak recommendation in the guidelines on quality control in vascular access surgery. Quality assessment criteria should be defined in this field of surgery. According to these criteria, patients and nephrologists could choose the best vascular access center or surgeon. Centers with best results should be referral centers, and centers with poorer results should implement quality improvement programs.

Introduction: The number of patients with end-stage renal failure (ESRF) that require inclusion in the renal replacement therapy program (RRT) is steadily increasing. This fact caused an increase in vascular operations involving the production of vascular access. According to the current guidelines, the best and safest option for a patient with chronic kidney disease (CKD) is the early creation of arteriovenous fistula (AVF). An efficient vascular access to haemodialysis determines the procedure and directly affects the quality of life of a patient with CKD., Aim: The aim of this paper is to present the author's project of the health policy program "Vascular access in renal replacement therapy - fistula first/catheter last", the essence of which is to assess the practical effectiveness and develop an optimal model of CKD patient care organization qualified for the chronic RRT program., Material and Methods: The target population of the program consists of all patients diagnosed with CKD, qualified for the RRT program. The basic measures of the program's effectiveness include: (1) reduction in the number of re-hospitalizations related to vascular access, (2) reduction in the number of complications associated with haemofiltration surgery, (3) reduction in general mortality among patients undergoing dialysis in a 12-month perspective, (4) increasing knowledge in the field of self-care and self-care of arteriovenous anastomosis, and (5) creating a register of vascular access in Poland., Conclusions: To sum up, health policy programme "Vascular access in renal replacement therapy - fistula first/catheter last" covering health care services provided in the scope and on the conditions specified in the regulations issued on the basis of article 31d of the Act of 27 August 2004 on health care benefits financed from public funds, is to check whether planned changes in the organization and delivery of services will improve the situation of patients with CKD eligible for chronic RRT and whether it will be effective the point of view of the health care system.

Quality improvement initiatives should be aimed to enhance clinical outcomes, service delivery and quality of life for patients. For patients reliant on haemodialysis, vascular access is a lifeline. Survival differences relating to the type of vascular access are evident and many initiatives have focussed on increasing absolute rates of arteriovenous fistulas and/or decreasing central venous catheter use. While these have achieved some success quantitatively, the qualitative effects are less obvious. The aims of this review article are to explore the concepts of quality of care in vascular access. There is a paucity of studies into the effects of vascular access on the quality of life of dialysis patients, and where studies have been performed, generalised patient-reported outcome measures have been used. To facilitate the implementation of quality improvement programmes specifically for vascular access requires suitable tools. While existing patient-reported outcome measures may be applicable to vascular access, it is likely that these will require further evaluation, and the development of vascular access-specific patient-reported outcome measures may be required.

Background: There are three principle forms of vascular access available for the treatment of children with end stage kidney disease (ESKD) by haemodialysis: tunnelled catheters placed in a central vein (central venous lines, CVLs), arteriovenous fistulas (AVF), and arteriovenous grafts (AVG) using prosthetic or biological material. Compared with the adult literature, there are few studies in children to provide evidence based guidelines for optimal vascular access type or its management and outcomes in children with ESKD., Methods: The European Society for Paediatric Nephrology Dialysis Working Group (ESPN Dialysis WG) have developed recommendations for the choice of access type, pre-operative evaluation, monitoring, and prevention and management of complications of different access types in children with ESKD., Results: For adults with ESKD on haemodialysis, the principle of "Fistula First" has been key to changing the attitude to vascular access for haemodialysis. However, data from multiple observational studies and the International Paediatric Haemodialysis Network registry suggest that CVLs are associated with a significantly higher rate of infections and access dysfunction, and need for access replacement. Despite this, AVFs are used in only ∼25% of children on haemodialysis. It is important to provide the right access for the right patient at the right time in their life-course of renal replacement therapy, with an emphasis on venous preservation at all times. While AVFs may not be suitable in the very young or those with an anticipated short dialysis course before transplantation, many paediatric studies have shown that AVFs are superior to CVLs., Conclusions: Here we present clinical practice recommendations for AVFs and CVLs in children with ESKD. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system has been used to develop and GRADE the recommendations. In the absence of high quality evidence, the opinion of experts from the ESPN Dialysis WG is provided, but is clearly GRADE-ed as such and must be carefully considered by the treating physician, and adapted to local expertise and individual patient needs as appropriate., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Background: Almost 80% of patients with end-stage renal disease (ESRD) initiate dialysis via a central venous catheter (CVC). CVCs are associated with multiple complications and a high cost of care. The purpose of our project is to determine the impact of early cannulation arteriovenous grafts (ECAVGs) on quality of care and costs., Methods: The dialysis access modality, complications, secondary interventions, hospital outcomes, and detailed costs were tracked for 397 sequential patients who underwent access creation between July 2014 and October 2018. Complications were grouped into deep vein thrombosis, line infections, sepsis, pneumothorax, and other. Secondary interventions included angioplasty, angioplasty and stent grafting, thrombectomy, surgical revision, and explantation. Hospital outcomes included length of stay, inpatient mortality, 30-day readmission, and discharge disposition. Costs included supplies, medications, laboratory tests, labor, and other direct costs. All variables were measured at the time of the index procedure, 30 days, 90 days, 180 days, 270 days, 1 year, 18 months, and 2 years., Results: There were 131 patients who underwent arteriovenous fistula (AVF) and 266 who received ECAVG for dialysis access. The total cost of care per patient was $17,523 for AVF and $5,894 for ECAVG at 1 year (P < 0.01). Primary-assisted patency for AVF was 49.3% versus 81.4% for ECAVG (P = 0.027), and secondary-assisted patency for AVF was 63.8% versus 85.4% for ECAVG at 1 year (P = 0.011). There was a survival advantage for ECAVGs at 1 year (78.6% for AVF vs 85.0% for ECAVG, P = 0.034). Patients who received ECAVG had fewer CVC days (2.3% vs 19.1% for AVF, P < 0.001), fewer complications (1.6% vs. 21.5% for AVF, P < 0.001), and fewer secondary interventions (17.0% vs 52.5% for AVF, P < 0.001)., Conclusions: This is the first study on patients with ESRD to report detailed outcomes and cost analysis as it relates to AVF versus ECAVG. ECAVGs have an advantage over AVFs due to lower overall cost and better clinical outcomes at 1 year. Implementation of an urgent start dialysis access program centered around ECAVGs may help achieve the national goal of better health care at a lower cost for patients with ESRD., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Guidelines recommend regular screening of mature arteriovenous fistulas (AVFs) for preemptive repair of significant stenosis (≥50% lumen reduction) at high risk of thrombosis, identifiable from clinical signs of access dysfunction (monitoring) or by measuring access blood flow (Qa surveillance), which also enables stenosis detection in functional accesses. To compare the value of Qa surveillance versus monitoring, a meta-analysis was performed on the randomized controlled trials (RCTs) comparing the two screening strategies. It emerged that correcting stenosis identified by Qa surveillance significantly halved the risk of thrombosis [relative risk (RR) = 0.51, 95% confidence interval (CI) 0.35-0.73] and access loss (RR = 0.47, 95% CI 0.28-0.80) in comparison with intervention prompted by clinical signs of access dysfunction. One small RCT aiming to identify an optimal Qa threshold showed that stenosis repair at Qa >500 mL/min produced a significant 3-fold reduction in the risk of thrombosis (RR = 0.37, 95% CI 0.12-0.97) and access loss (RR = 0.36, 95% CI 0.09-0.99) in comparison with intervening when Qa dropped to <400 mL/min as per guidelines. To test the real-world benefits of Qa surveillance, the expected RCT-based thrombosis and access loss rates with Qa surveillance were compared with the rates with monitoring reported in observational studies: the expected thrombosis and access loss rates with surveillance were only lower than with monitoring when a Qa >500 mL/min was considered (2.4, 95% CI 1.0-4.6 and 2.2, 95% CI 0.7-5.0 versus 9.4, 95% CI 7.4-11.3 and 10.3, 95% CI 7.7-13.4 events per 100 AVFs-year, P ≤ 0.024), suggesting that in clinical practice adopting Qa surveillance may only be worthwhile at centres with high thrombosis and access loss rates associated with monitoring, and adopting Qa thresholds >500 mL/min for elective stenosis repair., (© The Author(s) 2019. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Background: Radial artery diameter on preoperative ultrasound has previously been investigated as a risk factor for the primary patency rate of arteriovenous fistulas. However, the cutoff values for long-term secondary patency rates have not been reported in detail. The present study verified the cutoff values that predict long-term secondary patency., Methods: This was a single-center retrospective study. Among the arteriovenous fistula operations performed at our hospital from March 2008 to April 2013, 204 patients who underwent ultrasonography prior to the operation and whose secondary patency data were available were enrolled in this study. Secondary patency rates were calculated at 1, 3, and 5 years. Risk factors, including radial artery diameters (divided into quartiles), age, sex, diabetes mellitus, calcification, right versus left radial artery, and operative time (divided into quartiles) were examined using the log-rank test. Next, we performed multivariate Cox proportional hazard analysis using risk factors that were significant in the log-rank test. Further studies using time-dependent receiver operating characteristic curves were conducted to examine the cutoff values for radial artery diameters., Results: The 1-, 3-, and 5-year secondary patency rates were 78.9%, 69.8%, and 67.4%, respectively. Significant risk factors included radial artery diameter and age ≥65 years. The cutoff value was 2.0 mm., Conclusions: A radial artery diameter cutoff value of 2.0 mm may increase the secondary patency rate of arteriovenous fistulas. This result agrees with the radial artery diameter reported for primary patency rates and is a clinically significant indicator., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology (S.E.N.), vascular surgery (SEACV), interventional radiology (SERAM-SERVEI), infectious diseases (SEIMC), and nephrology nursing (SEDEN)), along with the methodological support of the Iberoamerican Cochrane Centre, has developed the Spanish Clinical Guidelines on Vascular Access for Hemodialysis. This article summarizes the main issues from the guideline's chapter entitled "Monitoring and surveillance of arteriovenous access." We will analyze the current evidence on conflicting topics such as the value of the flow-based screening methods for the arteriovenous access surveillance or the role of Doppler ultrasound as the imaging exploration to confirm suspected stenosis. In addition, the concept of significant stenosis and the criteria to perform the elective intervention for stenosis were reviewed. The adoption of these guidelines will hopefully translate into a reduced risk of thrombosis and increased patency rates for both arteriovenous fistulas and grafts.

Objectives: Upper arm arteriovenous fistulas (AVF) occasionally develop high flow. Revision using distal inflow (RUDI) effectively reduces flow of high flow accesses (HFA) in the short-term and is also popularised for treatment of haemodialysis access induced distal ischaemia (HAIDI). The long-term efficacy is unknown. The study's aim was to report on 3 year RUDI patency and recurrence rates for HFA with and without HAIDI., Material and Methods: This was a retrospective cohort study of patients with a HFA with or without HAIDI undergoing RUDI using greater saphenous vein (GSV) interposition between March 2011 and October 2017 at three facilities. AVFs were termed HFA if flow volumes exceeded 2 L/min on two consecutive measurements using dilution techniques. HAIDI was diagnosed as recommended. Following RUDI, follow up was not different from standard care in AVF patients. Data on post-operative flows and re-interventions were extracted from electronic patient files. Loss to follow up was avoided. Rates of patency and HFA recurrence were analysed., Results: During the observation period, 21 patients were studied (7 females, 54 years ± 3). Fourteen had uncomplicated HFA whereas seven had additional HAIDI. Immediately post-operatively, flows decreased threefold (3120 mL/min ± 171 vs. 1170 mL/min ± 87, p < .001). Overall 3 year primary patency was 48% ± 12 (HFA, 55% ± 15 vs. HAIDI/HFA, 29% ± 17, p = .042). Secondary patency was identical in both groups (overall, 84% ± 9). Interventions were percutaneous transluminal angioplasty (n = 12, 9 patients), thrombectomy (n = 7, 3 patients), and revision with new interposition grafts (n = 3). After 3 years, 51% ± 12 were free of high flow (HFA, 32% ± 13 vs. HAIDI/HFA, 100%, p = .018). High immediate post-operative access flow predicted recurrence (OR 1.004 [1.000-1.007], p = .044). Patients with recurrence were 12 years younger than those without (p = .055)., Conclusion: RUDI with GSV interposition for HFA offers acceptable patency rates after 3 years although re-interventions are often required. High immediate post-operative flows and young age are associated with recurrent high flow., (Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Objective: The urgency with which salvage of thrombosed vascular accesses for dialysis should be attempted remains unknown. We examined the effect of a timely thrombectomy approach on vascular access outcomes for dialysis., Methods: A before-and-after study was conducted with patients on hemodialysis who had undergone endovascular thrombectomy. A timely thrombectomy initiative (ie, salvage within 24 hours of thrombosis diagnosis) was started in July 2015 at our institution. Data about thrombectomy procedures, performed within 1 year before and after the initiative was introduced, were abstracted from an electronic database. Immediate outcomes and patency outcomes were compared between the preinitiative (control) and postinitiative (intervention) groups., Results: During the study period, 329 patients were enrolled, including 165 cases before and 164 cases after the initiative. The intervention group had more thrombectomy procedures performed within 24 hours (93% vs 55%; P < .01) and within 48 hours (97% vs 79%; P < .01) than the control group. No between-group differences in procedural success or clinical success rates were found. At 3 months, the intervention group had a higher postintervention primary patency rate than the control group, although this did not reach statistical significance (58% vs 48%; P = .06). After stratification into native or graft accesses, the patency benefit was observed in the native access group (68% vs 50%; P = .03) but not in the graft access group (50% vs 46%; P = .65). After adjusting for potential confounders, timely thrombectomy remained an independent predictor of postintervention primary patency (hazard ratio, 0.449; 95% confidence interval, 0.224-0.900; P = .02) for native dialysis accesses., Conclusions: Our results suggest that a timely thrombectomy approach, in which salvage is attempted within 24 hours of thrombosis diagnosis, improves postintervention primary patency of native but not graft accesses for dialysis., (Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Vascular access practice is strongly associated with clinical outcomes. There is substantial international variation in the use of arteriovenous fistulas (AVFs) and grafts (AVGs), as well as AVF maturation time and location., Study Design: Prospective cohort study., Setting & Participants: Hemodialysis patients participating in the prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) from the United States, Japan, and Europe/ANZ (Belgium, France, Germany, Italy, Spain, Sweden, United Kingdom, Australia, and New Zealand), including 3,850 patients receiving 4,247 new AVFs and 842 patients receiving 1,129 new AVGs in 2009 to 2015. AVF location trends were based on 38,868 AVFs recorded in DOPPS 1 to 5 cross-sections (1996-2015)., Predictors: Demographics, comorbid conditions, dialysis vintage, body mass index, facility percentage AVF use, median blood flow rate, and AVF location., Outcomes: AVF location; successful AVF/AVG use (≥30 days of continuous use); time-to-first successful AVF/AVG use (maturation)., Results: During DOPPS 1 to 5, the percentage of AVFs created in the lower arm was consistently ≥93% in Japan and 65% to 77% in Europe/ANZ, but in the United States, this value declined from 70% (DOPPS 1) to 32% (DOPPS 5). Patient characteristics associated with AVF location differed by region. Successful AVF use was 87% in Japan, 67% in Europe/ANZ, and 64% in the United States, whereas successful AVG use was 86%, 75%, and 78%, respectively. Successful AVF use was greater for upper- versus lower-arm AVFs in the United States, with little difference in Europe/ANZ and the opposite pattern in Japan. Median time until first successful AVF use was 10 days in Japan, 46 days in Europe/ANZ, and 82 days in United States; until first successful AVG use: 6, 24, and 29 days, respectively., Limitations: Potential measurement error related to chart data abstraction in multiple hemodialysis facilities., Conclusions: Large international differences exist in AVF location, predictors of AVF location, successful use of AVFs, and time to first AVF/AVG use, challenging what constitutes best practice. The large US shift from lower- to upper-arm AVFs raises serious concerns about long-term health implications for some patients and how policies and practices aimed at increasing AVF use have affected AVF placement location., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare., (Copyright © 2017 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

Background: Chronic kidney disease is common in the United States, with many patients maintained on hemodialysis (HD). The process of HD requires vascular access through an arteriovenous (AV) fistula, AV graft, or central venous catheter. Today, as a result of the National Kidney Foundation's "Fistula First" initiative, nearly 55% of HD patients utilize an AV fistula. As there is significant morbidity and mortality associated with fistula placement and recurrent fistula cannulation, emergency physicians must be equipped to recognize and treat fistula complications., Objective: To detail a case study of vascular insufficiency (vascular steal) presenting to an emergency department (ED) and provide an evidence-based approach to the emergency assessment and management of HD AV fistula complications., Discussion: A 66-year-old man presented to the ED with left upper extremity pain, paresthesias, and loss of grip strength of 1-week duration 15 days after placement of left upper extremity brachiocephalic fistula. He was diagnosed with dialysis access-associated steal syndrome and taken to the operating room for revision. Patients with HD fistulas may experience several complications, including vascular insufficiency, hemorrhage, infection, stenosis, thrombosis, aneurysms, or pseudoaneurysms. Emergency physicians must be able to identify these complications and deliver timely treatment., Conclusions: A comprehensive understanding of the appropriate management of AV fistula complications is paramount for the emergency physician. Early recognition and treatment of vascular insufficiency resulting from fistula creation, fistula hemorrhage, fistula infection, stenosis, thrombosis, and aneurysms or pseudoaneurysms is vital to reducing the morbidity and mortality associated with HD., (Published by Elsevier Inc.)

Background: Excessively long clamping time and suboptimal position of stitches can influence the anastomosis patency and the clinical outcome in cerebral bypass surgery. Coronary intravascular micro-shunts could represent an innovative solution for neurosurgical bypass, but the hemodynamic properties of these devices should be extensively studied before their translational application. We created an experimental in-vivo model and we analyzed the blood flow and pressure modification induced by the micro-shunt., Methods: After laparotomy, an intravascular micro-shunt was placed into the aorta of 8 adult rats, simulating a neurosurgical setting in which the shunt is temporary placed inside the receiving cerebral vessel. A fiber-optic pressure sensor was placed in the femoral artery and the blood pressure continuously recorded during the procedure. Using an ultrasound vascular probe, blood flow velocity in aorta was measured at baseline and both proximally and distally to the shunt., Results: After shunt positioning, no significant decrease in blood pressure was observed (mean value 68.57 versus 80.00 mmHg; P=0.48). Distal aortic blood flow, expressed as peak systolic velocity, showed a significant decrease after shunt positioning (mean value 51.88 versus 86.88 cm/sec; P=0.04), with a mean residual blood flow of 63%. Blood flow values recorded immediately upstream to the shunt did not differ from baseline., Conclusions: This is the first in-vivo experimental study concerning the hemodynamic properties of an intravascular micro-shunt. Our results demonstrate that this device provides a considerable blood out-flow without significant changes in blood pressure, suggesting that specific neurosurgical micro-shunts might be developed.

Objective: The Kidney Disease Outcome Quality Initiative and Fistula First Breakthrough Initiative call for the indiscriminate creation of arteriovenous fistulas (AVFs) over arteriovenous grafts (AVGs) without providing patient-specific criteria for vascular access selection. Although the U.S. AVF rate has increased dramatically, several reports have found that this singular focus on increasing AVFs has resulted in increased AVF nonmaturation/early failure and a high prevalence of catheter dependence. The objective of this study was to determine the appropriateness of vascular access procedures in clinical scenarios constructed with combinations of relevant factors potentially influencing outcomes., Methods: The RAND/UCLA Appropriateness Method was used. Accordingly, a comprehensive literature search was performed and a synthesis of results compiled. The RAND/UCLA Appropriateness Method was applied to 2088 AVF and 1728 AVG clinical scenarios with varying patient characteristics. Eleven international vascular access experts rated the appropriateness of each scenario in two rounds. On the basis of the distribution of the panelists' scores, each scenario was determined to be appropriate, inappropriate, or indeterminate., Results: Panelists achieved agreement in 2964 (77.7%) scenarios; 860 (41%) AVF and 588 (34%) AVG scenarios were scored appropriate, 686 (33%) AVF and 480 (28%) AVG scenarios were scored inappropriate, and 542 (26%) AVF and 660 (38%) AVG scenarios were indeterminate. Younger age, larger outflow vein diameter, normal or obese body mass index (vs morbidly obese), larger inflow artery diameter, and higher patient functional status were associated with appropriateness of AVF creation. Older age, dialysis dependence, and smaller vein size were associated with appropriateness of AVG creation. Gender, diabetes, and coronary artery disease were not associated with AVF or AVG appropriateness. Dialysis status was not associated with AVF appropriateness. Body mass index and functional status were not associated with AVG appropriateness. To simulate the surgeon's decision-making, scenarios were combined to create situations with the same patient characteristics and both AVF and AVG options for access. Of these 864 clinical situations, 311 (36%) were rated appropriate for AVG but inappropriate or indeterminate for AVF., Conclusions: The results of this study indicate that patient-specific situations exist wherein AVG is as appropriate as or more appropriate than AVF. These results provide patient-specific recommendations for clinicians to optimize vascular access selection criteria, to standardize care, and to inform payers and policy. Indeterminate scenarios will guide future research., (Published by Elsevier Inc.)

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.

Aim: To provide the contemporary use of upper-arm access for hemodialysis in Sweden using data from a unique national registry for hemodialysis access., Methods: Data were retrieved from a nation-wide registry for dialysis access in Sweden, Dialysis Access Database (DiAD) on the use and function of specific access types with a focus on upper-arm accesses., Results: The data demonstrate an increased use of upper-arm access, likely dependent on a changing patient population, with brachiocephalic arteriovenous fistula (AVF) as the most common access type. Women received more upper-arm accesses than men. Given the recent establishment of the registry, patency and access function can at this point give preliminary data. Indications of a better function for brachiobasilic AVFs in staged procedures were observed as well as for upper-arm arteriovenous grafts (AVGs) in women., Conclusions: Registry data support an increased use of upper-arm accesses, especially in women. The study also demonstrates the potential of a dedicated national access registry to improve access care.

Many guidelines recommend that end-stage renal disease (ESRD) patients should have a permanent vascular access, preferably an autologous arteriovenous fistula (AVF), at the start of renal replacement therapy. Nevertheless, a large proportion of patients still start hemodialysis with a central venous catheter (CVC). On the other hand, there are increasing numbers of patients in whom an AVF has been created, but who never actually end up on dialysis, as well as a substantial number of patients in whom creation of a vascular access has been attempted unsuccessfully.To improve this situation, timely exploration to assess suitability for and creation of preemptive AVF should be promoted. Decision to construct an AVF should depend on the likelihood and rate of progression to ESRD. For this goal, some reliable prediction models are available. Also, the likelihood that such an attempt will result in a successful outcome should be taken into account, but suitable validated models to accurately make such estimates are lacking. Next to patient-specific factors, some local conditions such as easy access to a vascular surgeon should also be incorporated in the decision-making process between the nephrology team and the patient.

Dialysis vascular access management in the United States changed significantly after National Kidney Foundation-Kidney Disease Outcome Quality Initiative (NKF-KDOQI) clinical practice guidelines were first published in 1997. The Centers for Medicare and Medicaid Service adopted these guidelines and in collaboration with the End-Stage Renal Disease Networks established the Fistula First Breakthrough Initiative (FFBI) in 2003 to improve the rate of arteriovenous fistula use over arteriovenous graft and central venous catheter in the dialysis population. The implementation of guidelines and FFBI has led to a significant increase in the arteriovenous fistula use in the prevalent dialysis population. The guidelines are criticized for being opinion based and often impractical. Over the past 2 decades, the patient population undergoing dialysis has become older with complex comorbidities and challenges for creating an ideal vascular access. Advancing knowledge about access pathophysiology, improved treatment options, and improved process of care with team approach model point toward diminishing relevance of few of the existing guidelines. Moreover, several guidelines remain controversial and may be leading to clinical decisions that may be unfavorable to the patients. The review discusses the historical aspect of vascular access care in the United States and evolution of current practice standards and controversies surrounding few of these guidelines in the current time., (Published by Elsevier Inc.)

Interventional radiologists play a central role in the care of patients with end-stage renal disease receiving renal replacement therapy. Ensuring that a patient׳s dialysis access remains suitable for high-quality dialysis is of paramount importance. However, although much has been spoken and written about endovascular techniques and outcomes based on angiographic criteria, little is generally known regarding the function and therefore the requirements of hemodialysis. In this article, we provide a heuristic overview of the mechanics of hemodialysis, with an emphasis on the "breaking points" in the extracorporeal circuit that trigger a patient׳s referral to Interventional Radiology. We also describe how dialysis quality is increasingly becoming linked with dialysis reimbursements. It is thus becoming progressively incumbent on the interventional radiologist to not only ensure that a patient receives high-quality outpatient dialysis but also that the patient׳s dialysis center meets its performance metrics., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Most guidelines recommend the creation of arteriovenous fistula (AVF) in patients with chronic kidney disease (CKD) stage 4. However, an increasing number of studies suggest that early AVF creation leads to high rates of AVF failure and death before dialysis commencement. Only the Japanese guideline recommends AVF creation at CKD stage 5; however, no data are available regarding access-related outcomes at this stage., Method: This was a multicenter cohort study involving Japanese CKD stage 5 patients who underwent preemptive AVF creation from 2009 to 2013. The primary outcome was unnecessary AVF creation, defined as death before requiring dialysis or AVF failure before dialysis commencement. The secondary outcome was dialysis commencement. The associations with candidate predictors and the outcomes were examined., Results: A total of 303 patients were registered. Four cases of death before dialysis and 13 cases of AVF failure before dialysis commencement were observed. A total of 283 patients who advanced to dialysis were found to have functional AVFs. The cumulative incidences of unnecessary AVF creation and dialysis commencement at 1 year were 4.8 and 89.3%, respectively. Competing risk regression analyses showed that age ≥75 years (subhazard ratio [SHR] 3.12, 95% CI 1.20-8.09) and female gender (SHR 3.31, 95% CI 1.20-9.09) were associated with unnecessary AVF creation., Conclusions: A low incidence of unnecessary AVF creation was revealed among Japanese patients who received AVF at CKD stage 5. These results may help clarify the natural history of unnecessary AVF creation for other countries reformatting their guidelines regarding late vascular access creation., (© 2017 S. Karger AG, Basel.)

Background: Commencing hemodialysis (HD) using a catheter is associated with a higher risk of adverse outcomes, and early conversion from central-venous catheter (CVC) to arteriovenous fistula/graft (non-CVC) improves outcomes. We investigated CVC prevalence and conversion, and their effects on outcomes during the first year of HD in a multinational cohort of elderly patients., Methods: Patients ≥70 years from the MONDO Initiative who commenced HD between 2000 and 2010 in Asia-Pacific, Europe, North-, and South-America and survived at least 6 months were included in this investigation. We stratified by age (70-79 years [younger] vs. ≥80 years [older]) and compared access types (at first and last available date) and their changes. We studied the association between access at initiation and conversion, respectively, and all-cause mortality using Kaplan-Meier curve and Cox regression, and predicted the absence of conversion from catheter to non-CVC using adjusted logistic regression., Results: In 14,966 elderly, incident HD patients, survival was significantly worse when using a CVC at all times. In Europe, the conversion frequency from CVC to non-CVC was higher in the younger fraction. Conversion from non-CVC to CVC was associated with worsened outcomes only in the older fraction., Conclusion: These results corroborate the need for early HD preparation in the elderly HD population. Treatment of elderly patients who commence HD with a CVC should be planned considering aspects of individual clinical risk assessment. Differences in treatment practices in predialysis care specific to the elderly as a population may influence access care and conversion rate., (© 2017 S. Karger AG, Basel.)

The incident hemodialysis (HD) population is aging, and the elderly group is the one with the most rapid increase. In this context it is important to define the factors associated with outcomes in elderly patients. The high prevalence of comorbidities, particularly diabetes mellitus, peripheral vascular disease and congestive heart failure, usually make vascular access (VA) creation more difficult. Furthermore, many of these patients may have an insufficient vasculature for fistula maturation. Finally, many fistulas may never be used due to the competing risk of death before dialysis initiation. In these cases, an arteriovenous graft and in some cases a central venous catheter become a valid alternative form of VA. Nephrologists need to know what is the most appropriate VA option in these patients. Age should not be a limiting factor when determining candidacy for arteriovenous fistula creation. The aim of this position statement, prepared by experts of the Vascular Access Working Group of the Italian Society of Nephrology, is to critically review the current evidence on VA in elderly HD patients. To this end, relevant clinical studies and recent guidelines on VA are reviewed and commented. The main advantages and potential drawbacks of the different VA modalities in the elderly patients are discussed.

Background: The aim of the study was to assess whether age, gender and the primary renal disease are associated with differences in the type of first vascular access placement., Methods: We reviewed the records of 145 patients on hemodialysis (HD) 44 females and 101 males with a mean age of 64±14.5 years, on HD for 46.9±41.2 months (range 1-252)., Results: The primary renal diseases were diabetes (23.4%), hypertension (17.2%), glomerulonephritis (25.7%), cardiac failure (6.9%) and others (26.8%). Double lumen catheter and arteriovenous fistula was the first vascular access in 109 (75%) and 35 patients (24%) patients, respectively. Graft was the first vascular access in 1 patient (0.5%). Arteriovenous fistula was the first choice for 29.7% of the male patients and 9% of the female. Double lumen catheter was the first choice for 70.3% of the male (subclavian 50.5%, femoral 4.95%, and jugular 14.85%) and 86.4% of the female (subclavian 75%, femoral 2.3%, and jugular 9.1%) (P=0.04). Double lumen catheter was the first choice for 79.7% of the patients older than 65 years and 70.4% for the patients younger than 65 years (P=0.19). Double lumen catheter was the first choice for all the patients with cardiac failure as the primary cause of renal disease., Conclusion: Double lumen catheter was the first vascular access for the majority of our patients, probably due to late Nephrologist's referral. Cardiac failure being the primary cause of renal disease and female gender influence also this choice, but not the age of the patients.

Background: Optimizing vascular access outcomes is still a challenge, since 30-60% of arteriovenous fistulas fail or do not mature and catheters are widely used in contemporary patients., Methods: This study reports on strategies and outcomes in a single center in which access planning, surgery and maintenance are managed by a team of nephrologists. We retrospectively analyzed 305 fistulas and 61 grafts created in 270 consecutive patients between 2002 and 2013., Results: The percentage of patients receiving a fistula or graft who initiated hemodialysis with a mature access was 68.6%. Among prevalent patients, 71.7% used a fistula, 15.7% a graft and 12.6% a catheter. Rates of primary failure and revision before cannulation were 14.4 and 1.6% for fistulas vs. 4.9 and 3.3% for grafts. After maturation, complications (1.040 vs. 0.188 per patient-year (py)) and interventions (0.743 vs. 0.066 per py) were greater for grafts than for fistulas (p < 0.001). Secondary patency did not significantly differ between grafts and fistulas (median survival 34.8 vs. 57.3 months, p = 0.36), unless primary failures were excluded from Kaplan-Meier analysis (median survival 34.9 vs. 70.9 months, p = 0.03)., Conclusions: High fistula prevalence, low access-related morbidity and catheter dependence were achieved using individualized strategies, including mid-forearm or perforating vein fistula creation and selective graft placement in high risk patients. Direct involvement of nephrologists throughout all steps of access care can improve access outcomes, by promoting a patient-centered approach., (© 2016 S. Karger AG, Basel.)

Purpose: The aim of this study is to determine the optimal range of cephalic vein and radial artery diameter following preoperative duplex imaging to enhance maturation and primary patency of Brescia-Cimino radiocephalic arteriovenous fistula., Methods: A systematic review and meta-aggregation of literature from 1966 to January 2015 in English language and adult subjects in Pubmed, OVID, CINHAL and Cochrane database was conducted., Results: This search produced a total of thirty-six (n = 36) articles. Following the application of recruitment criteria, only twelve articles (n = 12) were found eligible. Their quality was assessed by Oxford Critical Appraisal skills Programme (CASP) and their recommendation for practice was examined through National Institute for Health and Care Excellence (NICE)., Conclusions: The current literature suggests that the optimal range of radial artery for maximum performance (maturation and primary patency) of RCAVF is at least 2 mm (level 2, grade a). The cephalic vein diameter of at least 2 mm (non-augmented) can result in best maturation and primary patency outcomes (level 2, grade a) and threshold below 1.5 mm is not advocated (level 2, grade b).

Introduction: The Japanese Society for Dialysis Access (JSDA) has held the practical skills trainings for the doctors working for the vascular access (VA) access since 2014 in order to improve both quality and quantity of the VA construction. Terumo Medical Pranex (Kanagawa, Japan) is the institution of the general medical training established for the creation and the spread of medical technique, and it also has the hybrid simulator of VA., Methods and Results: In the training institute in 2014, not only the practical skills but also the training on the simulator from the basic lecture of VA construction were conducted. The dummy of a radical artery and a cephalic vein is faked in the forearm on the simulator. Two carotid arteries of a pig are made as the position of a pair of artery and vein. The pig's skin taken from the neck to the chest is covered on the proceed part, then the dummy forearm was completed. We can make recognize the beats in the artery. We also can make a fake avf in the dummy forearm instead. The instructor is directly able to give the trainees the lectures while watching the scenes. jsda will continue to make such efforts from now., Conclusions: We are concerned that the more the VA access would be demanded, the more the VA construction would be needed. So, the matter of the urgency is the training of the doctors working for VA construction.

In Japan, the number of patients receiving dialysis is 314,180 at the end of 2013 and 97% are treated with hemodialysis. And the mean age of patients and the percentage of diabetes have been increasing. For this reason, preparations of a new vascular access (VA) and its long-term maintenance have become difficult. In the guidelines by the Japanese Society for Dialysis Therapy (JSDT), endovascular treatment (ET) is positioned as the first line for VA stenosis. The procedure of ET itself is very simple. The revision of Japanese health insurance set an expensive technical fee for ET in 2012. It also added a restriction by which the claims for both technical and material fees would be denied, if the treatment was performed within 3 months after a previous treatment. This makes determination of best treatment timing more important. The functional evaluation using ultrasonography (US) is a useful monitoring index for determination of the ET timing for patients with stenosis. We investigated the cumulative relative frequency of flow volume (FV) and resistant index (RI) of brachial artery in arteriovenous graft (AVG) and arteriovenous fistula (AVF) cases with access failures. As a result, the cut-off values of FV and RI in AVG were 480 mL/min and 0.57, and in AVF were 354 mL/min and 0.61, respectively. Therefore we determine the treatment timing based on these results. Since 2012, active monitoring using US could have decreased the number of treatment patients by 100 per year. This meant that objective evaluation by US enabled treatments at a more suitable time to promote the proper use of medical expenses for EV treatment.

Hemodialysis vascular access is at the same time both the "Lifeline" and the "Achilles Heel" of hemodialysis. This review will initially summarize the vascular biology of dialysis vascular access dysfunction and then use this information to describe some novel and innovative ways (including advances in the process of care for vascular access) to prevent this problem., (© 2014 Wiley Periodicals, Inc.)

The long-term survival and quality of life of patients on hemodialysis is dependent on the adequacy of dialysis via an appropriately placed vascular access. Recent clinical practice guidelines recommend the creation of native arteriovenous fistula or synthetic graft before start of chronic hemodialysis therapy to prevent the need for complication-prone dialysis catheters. The direct involvement of nephrologists in the management of referral patterns, predialysis follow-up, policy of venous preservation, preoperative evaluation, vascular access surgery and vascular access care seems to be important and productive targets for the quality of care delivered to the patients with end-stage renal disease. Early referral to nephrologists is important for delay progression of both kidney disease and its complications by specific and adequate treatment, for education program which should include modification of lifestyle, medication management, selection of treatment modality and instruction for vein preservation and vascular access. Nephrologists are responsible for on-time placement and adequate maturation of vascular access. The number of nephrologists around the world who create their own fistulas and grafts is growing, driven by a need for better patient outcomes on hemodialysis. Nephrologists have also a key role for care of vascular access during hemodialysis treatment by following vascular access function using clinical data, physical examination and additional ultrasound evaluation. Timely detection of malfunctioning vascular access means timely surgical or radiological intervention and increases the survival of vascular access.

Exponential growth and increasing longevity of end-stage renal disease (ESRD) has resulted in significant ongoing changes in vascular access (VA) planning and management in the United States. There is a positive trend showing an increase in arteriovenous fistula (AVF) prevalence both in incident and prevalent patients and a decrease in tunneled dialysis catheters (TDCs) in prevalent patients. Current surgical training seems to provide adequate exposure to VA and an ample opportunity to develop skills required for safe surgical placement of VA. The prevalent differences in practice patterns suggest a need for standardization of VA care. There is a need for a structured curriculum in VA, which is a critical component in making sound decisions in access planning and management.

Vascular surgeons are essential in "lifeline" creation for hemodialysis patients and should be the central player in any multidisciplinary access service together with nephrologists, dialysis staff and interventional radiology. In this position, access surgeons are involved in complicated clinical decision making regarding primary and secondary access selection, which throughout the last decade has been largely aided, and influenced, by national and international guidelines as well as other initiatives. These recommendations, unanimously and appropriately, advocate the placement of native fistulas over synthetic grafts (the majority grafts from expanded polytetrafluoroethylene, ePTFE, herein referred to as PTFE) based on the superiority of fistulas with respect to complications such as infections and thrombosis. Nevertheless, the use of PTFE grafts for hemodialysis access is an accepted and firmly established alternative to native fistulas where data today reveal unwanted consequences to overinterpretation of established guidelines such as increased catheter use. This information highlights a need for an adjustment of access selection strategies based on patient-centered algorithms. Here, available results on PTFE graft performance in hemodialysis access is recapitulated, with respect to both conventional grafts and technical modifications, and conclude with a modified approach to primary access selection.

Purpose: The current guidelines for arteriovenous graft (AVG) configuration in hemodialysis state the following sequence: forearm loop, upper arm straight or curved and upper arm looped. These recommendations are based upon literature from the 1980s. Modern patient demographics and patient treatment algorithms, i.e., the Fistula First initiative (FFI), have greatly changed the current practice environment. It is not clear if these changes alter the outcomes of AVGs based upon configuration., Methods: The most recent National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF/K-DOQI) guidelines for vascular access were reviewed. Articles cited to support recommendations for AVG configuration were evaluated. The following search terms: arteriovenous graft configuration, access configuration, PTFE configuration in hemodialysis and straight, looped, curved graft configuration were used to search PubMed, Ovid, Medline and Google scholar. Articles that included data comparing AVG configuration were included. Citations within those articles were examined for publications overlooked in the initial search. Four articles and one abstract were reviewed and separated into pre- and post-FFI groups., Results: Pre-FFI articles demonstrate superiority of forearm looped AVG over straight forearm grafts. Post-FFI, the literature suggests that primary patency, thrombosis and steal are not affected by configuration and location, although looped configuration may have superior secondary patency., Conclusions: The available literature is mixed regarding the effect of configuration on AVG outcomes. Current studies illustrate the effect may be limited and that larger randomized controlled trials are necessary to draw firm conclusions. Regardless, adequate inflow and an appropriately sized outflow vein are paramount for optimal graft performance.