Arteriovenous Fistula Use Research Articles

Hemodialysis and peritoneal dialysis access related outcomes in the pediatric and adolescent population

BackgroundThere is paucity of comparative data on the objective performance of arteriovenous fistulas (AVF), grafts (AVG), hemodialysis (HD) catheter and peritoneal dialysis (PD) catheter in the pediatric population. MethodsA retrospective analysis of all patients <21 years in the United States Renal Database System who had an AVF, AVG, HD catheter or PD catheter placed for dialysis access between 1/2007 and 12/2014 was performed. Multivariable cox regression was used to evaluate mortality, patency (primary, primary-assisted and secondary), maturation and catheter survival. ResultsThe 11,575 patients studied comprised of 9445 (82%) HD, 1435 (12%) PD, 528 (4.6%) HD to PD and 167 (1.4%) PD to HD patients. The HD subcohort comprised of 1296 (13.7%) AVF initiates, 199 (2.1%) AVG initiates, 1347 (14.3%) AVF converts after initial HD catheter use, 292 (3.1%) AVG converts and 6311 (67%) patients who persistently utilized HD catheters. There was no difference between PD and HD in patients 0–5 (aHR: 1.36; 95% CI: 0.89–2.07; P = 0.15) and 6–12 years (aHR: 1.05; 95% CI: 0.72–1.52; P = 0.8). However, PD was associated with 73% and 76% increase in mortality relative to HD among patients in the 13–17 (aHR: 1.73; 95% CI: 1.35–2.21; P < 0.001) and 18–20 (aHR: 1.76; 95% CI: 1.38–2.24; P < 0.001) age categories. AVG was associated with 78% increase in mortality compared to AVF (aHR: 1.78; 95% CI: 1.41–2.25; P < 0.001). Persistent use of HD catheters was associated with 29% increase in mortality (aHR: 1.29; 95% CI: 1.07–1.57; P = 0.009) compared to initiation and persistent use of AVF. Conversion from HD catheter to AVF was associated with 66% decrease in mortality compared to persistent HD catheter use (aHR: 0.34; 95% CI: 0.28–0.40; P < 0.001). Primary, primary assisted and secondary patency were higher for AVF compared to AVG. ConclusionThere was no difference in risk adjusted mortality between HD and PD in children less than 13 years. PD is associated with higher mortality compared to HD in adolescents. Initiation of HD with AVF is associated with better patency and patient survival relative to AVG and persistent use of HD catheters in pediatric patients irrespective of transplant potential. Conversion from HD catheter to AVF or AVG in patients who inevitably initiate HD with a catheter is associated with better survival compared to persistent HD catheter use. Type of studyRetrospective cohort study. Level of evidenceLevel II.

Arteriovenous Fistula Use in the United States and Dialysis Facility–Level Comorbidity Burden

Patients with multiple comorbid conditions are less likely to use an arteriovenous fistula (AVF) for hemodialysis vascular access. Some dialysis facilities have high rates of AVF placement despite having patients with many comorbid conditions. This study describes variation in facility-level use of AVFs across the facility-level burden of patient comorbid conditions. Retrospective cohort study. Medicare patients receiving hemodialysis for 1 year or more in US dialysis facilities. Facility-level burden of patient comorbid conditions; patient characteristics. Odds of AVFs versus other access types; facility-level use of AVFs. Facility-level comorbidity burden was calculated by summing individual comorbid conditions, determining the average per patient, then defining 11 groups based on facility percentile ranking. Generalized estimating equations with a logit link were used to estimate the odds of AVF placement at the patient level. For the facility-level analysis, a generalized estimating equation model with the identity link was fit to characterize the percentage of AVF use at each facility. Overall, AVF use was 65.8% in 315,919 prevalent hemodialysis patients among 5,813 facilities. After adjustment for patient characteristics, AVF use was 0.27, 0.30, 1.05, and 1.74 percentage points lower than the median among facilities in the 61st to 70th, 71st to 80th, 81st to 90th, and 91st to 99th percentiles of comorbidity, respectively, and 0.42, 0.63, 1.34, and 1.90 percentage points higher than the median among facilities in the 31st to 40th, 21st to 30th, 11th to 20th, and 1st to 10th percentiles of comorbidity, respectively. Facilities in the greater than99th percentile of comorbidity burden had AVFuse that was 3.47 percentage points lower than the median. Facilities in the less than 1st percentile ofcomorbidity burden had AVF use that was 2.64 percentage points greater than the median. Limited to Medicare dialysis-dependent patients treated for 1 year or more. After adjustment for patient characteristics, we found small differences in facility rates of AVF use except in the extremes of high or low levels of comorbidity burden. Our study demonstrates that dialysis facilities with a relatively highpatient comorbidity burden can achieve similar fistula rates as facilities with healthier patients. Although high comorbidity burden does not explain low facility AVF use, additional study is needed to understand differences in AVF use rates between facilities with similar comorbidity burdens.

Patients referred for arteriovenous fistula construction: a retrospective outcome analysis.

With lower rates of sepsis and re-interventions, arteriovenous fistula (AVF) is the preferred vascular access modality. The aim of this study is to evaluate the outcomes of patients referred for AVF construction at a single center in Cork, Ireland. The current study is a single-center retrospective review of all patients who underwent AVF creation between 2015 and 2017. Additionally, the kidney disease clinical patient management system was used to provide statistics on AVF use in Ireland. 39.3% of hemodialysis patients in Ireland use an AVF for vascular access. Regional use ranged from 50 to 20% across Irish hemodialysis centers. At Cork University Hospital, 192 AVFs were created. The population was 69.3% male (n = 133), 30.7% female (n = 59) with a mean (±SEM) age of 58.8 ± 1.03years. 69.5% of females received a brachiocephalic AVF (BCAVF) while 13.6% had a radiocephalic AVF (RCAVF) constructed. Significance was seen when comparing gender and AVF type (p < 0.001). Fifty-four percent of the fistulae were brachiocephalic (n = 103), 33% were radiocephalic (n = 63), and 4% were brachiobasilic (n = 8). BCAVF patients (62.7 ± 1.2years) were significantly older than patients receiving a RCAVF (54.5 ± 1.9years, p < 0.001). A post-operative thrill or continuous flow on Doppler was present in 99% of patients (n = 190) with maturation and complication rates of 82.7% (n = 153) and 5.7% (n = 11) respectively. 69.9% of AVFs were needled for hemodialysis (n = 114). AVF outcomes at this center are consistent with reported statistics in the literature. Patient age, sex, and diabetic status may influence the use of proximal AVF. AVF creation rates in Ireland are below international reported recommendations.

Predictive Factors for Unsuccessful Use of Arteriovenous Fistula in a Population of End-Stage Renal Disease Patients in Southeastern Mexico

An arteriovenous fistula (AVF) is the preferred vascular access for long-term hemodialysis. The main disadvantage of AVF is the rate of nonmaturation or unsuccessful use for hemodialysis (FUHD). We described our findings in AVF creation and possible risk factors associated with FUHD. This is a retrospective study of AVFs during a 6-year period. Variables collected at the time of creation were demographics, comorbidities, replacement therapy, preoperative laboratory tests, and estimated 6-month mortality on hemodialysis. All AVFs were created in the upper arms. Outcomes were FUHD, cannulation failure, and cumulative survival. Univariate and multivariate analyses were performed to find possible risk factors for FUHD. AVFs were created in 78 patients. Average age was 36.3years, and 74.4% were male. Mean body mass index was 24.5kg/m2. The most common etiologies were glomerulopathy (53.6%) and diabetes mellitus (13.4%). Estimated six-month mortality was 4.2%. One patient underwent AVF before hemodialysis (mean dialysis time 2.2years). Nineteen AVFs were considered FUHD (23.2%). Cannulation failure was 15.9%. AVF 1-year and 3-year survival was 67.8% and 63.5%, respectively. FUHD had higher estimated six-month mortality on hemodialysis, shorter prothrombin time, and lower serum albumin level than successful AVF (univariate analysis) (P<0.05) Short prothrombin time and albumin were confirmed for FUHD (multivariate analysis). A 3.3-gr/dL serum albumin cutoff point (area under the curve, 0.715; receiver operating characteristic) (P<0.05) was determined for FUHD. The population referred for AVF creation possesses different characteristics in our center. Good AVF outcomes can be achieved. Preoperative serum albumin level and prothrombin time could be the possible risk factors associated with unsuccessful AVF use.

Costs Attributable to Arteriovenous Fistula and Arteriovenous Graft Placements in Hemodialysis Patients with Medicare coverage

Introduction: Hemodialysis (HD) in end-stage renal disease (ESRD) patients requires vascular access (VA) through an arteriovenous fistula (AVF), a prosthetic arteriovenous graft (AVG), or a central venous catheter. While AVF or AVG is commonly used for HD, the economic implications of AVF versus AVG use have not been fully established. We describe the healthcare resource utilization and costs of AVF and AVG use for incident ESRD patients in the United States. Methods: This observational cohort study of AVF and AVG placements used data from the United States Renal Data System to identify and follow access placements. AVF and AVG placements after ESRD onset for incident patients from 2012 to 2014 with continuous Medicare primary coverage were included. All-cause and access-related Medicare costs were averaged over the placement lifetime and expressed as per dialysis-month costs. Results: The analysis included 38,035 AVF placements and 12,789 AVG placements. Total all-cause monthly costs for AVF averaged USD 8,508; mean monthly costs were USD 3,027 for inpatient (IP), USD 3,139 for outpatient (OP), USD 1,572 for physician services, and USD 770 for other care settings. Access-related monthly costs averaged USD 1,699 and represented 20% of all-cause charges for AVFs. Mean all-cause monthly costs for AVG were USD 9,605; by setting monthly costs were USD 3,811 for IP, USD 3,034 for OP, USD 1,881 for physician services and USD 879 for other care settings. Access-related monthly costs averaged USD 2,656 and represented 28% of all-cause charges for AVGs. Discussion/Conclusions: This study indicates that costs due to VA are a significant burden on Medicare budgets and on patients. The factors driving access-related utilization and costs merit attention in future research. Both optimizing process of care and discovery innovation may significantly accelerate better stewardship of available healthcare resources.

SUN-050 STRATIFICATION OF CARDIOVASCULAR DEATH RISK BY ARRHYTHMIA, HEART FAILURE, AND DIABETES IN A PREVALENT COHORT OF DIALYSIS PATIENTS IN THE UNITED STATES

In recent years, progress toward improved survival among dialysis patients in the United States (US) has slowed, despite nearly universal prevalence of adequate urea clearance during hemodialysis, widespread use of arteriovenous fistulas and grafts for vascular access, and steady growth in the utilization of peritoneal dialysis among new dialysis patients. This discordance suggests that the fundamental model of dialysis—that is, peritoneal dialysis in a minority of new patients and thrice-weekly high-flux hemodialysis for 3.0–4.5 hours per session in almost all other patients—insufficiently addresses the morbidity of US dialysis patients.

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

Initial hemodialysis access with arteriovenous fistula (AVF) is associated with superior clinical outcomes compared with arteriovenous graft (AVG) and should be the procedure of choice whenever possible. To address the national underuse of AVF in the United States, the Centers for Medicare & Medicaid has established an AVF goal of 66% or greater in 2009. To explore contemporary practice patterns and physician characteristics associated with high AVG use compared with AVF use. This review of 100% Medicare Carrier claims between January 1, 2016, and December 31, 2017, includes both inpatient and outpatient Medicare claims data. All patients undergoing initial permanent hemodialysis access placement with an AVF or AVG were included. All surgeons performing more than 10 hemodialysis access procedures during the study period were analyzed. Placement of an AVF or AVG for initial permanent hemodialysis access. A surgeon-level AVG (vs AVF) use rate was calculated for all included surgeons. Hierarchical logistic regression modeling was used to identify patient-level and surgeon-level factors associated with AVG use. A total of 85 320 patients (median age, 70 [range, 18-103] years; 47 370 men [55.5%]) underwent first-time hemodialysis access placement, of whom 66 489 (77.9%) had an AVF and 18 831 (22.1%) had an AVG. Among the 2397 surgeons who performed more than 10 procedures per year, the median surgeon level AVG use rate was 18.2% (range, 0.0%-96.4%). However, 498 surgeons (20.8%) had an AVG use rate greater than 34%. After accounting for patient characteristics, surgeon factors that were independently associated with AVG use included more than 30 years of clinical practice (vs 21-30 years; odds ratio, 0.85 [95% CI, 0.75-0.96]), metropolitan setting (odds ratio, 1.25 [95% CI, 1.02-1.54]), and vascular surgery specialty (vs general surgery; odds ratio, 0.77 [95% CI, 0.69-0.86]). Surgeons in the Northeast region had the lowest rate of AVG use (vs the South; odds ratio, 0.83 [95% CI, 0.73-0.96]). First-time hemodialysis access benchmarking reports for individual surgeons were created for potential distribution. In this study, one-fifth of surgeons had an AVG use rate above the recommended best practices guideline of 34%. Although some of these differences may be explained by patient referral practices, sharing benchmarked performance data with surgeons could be an actionable step in achieving more high-value care in hemodialysis access surgery.

Endovascular Creation of Arteriovenous Fistulae for Hemodialysis Access with a 4 Fr Device: Clinical Experience from the EASE Study

The use of arteriovenous fistula (AVF) is hampered by long surgical wait times, slow maturation, and upwards of 60% that do not mature. We describe our clinical experience in using a system with a 4F catheter profile for endovascular AVF creation in patients on hemodialysis. This was a multioperator, single-center, single-arm, prospective study intended to evaluate safety and efficacy of a 4 Fr endovascular AVF (endoAVF) system for the creation of vascular access in hemodialysis patients. The study was performed after institutional review board approval at Italian Hospital (Asuncion, Paraguay). Patients were followed up at regular intervals through 6months to determine procedural, maturation, and cannulation success as well as intervention rate and patency. From May to November 2016, 32 patients underwent the endoAVF procedure with no device-related adverse events. An endoAVF was successfully created in the proximal forearm for all 32 patients (20 between the radial artery and radial vein; 12 between the ulnar artery and ulnar vein). Wrist access was used for 72% (23/32) of the procedures for the arterial catheter and 59% (19/32) of the procedures for the venous catheter. The device successfully created an endoAVF in every patient for a technical success rate of 100% (32/32). The device- or procedure-related serious adverse event rate was 3% (1/32); one patient experienced a venous guidewire perforation successfully managed with a stent graft. Primary and cumulative patency rates through 6months were 83% and 87%, respectively, with an intervention rate of 0.21 per patient-year. Physiological suitability, as defined by target flow rates ≥500ml/min and cannulation vessel diameters ≥4mm, was achieved in 91% (29/32) of patients by 90days. Successful 2-needle cannulation was achieved in 78% (21/27) by 90days, with mean time to cannulation of 43±14days. Functional cannulation, as defined by successful 2-needle cannulation for two-thirds of the dialysis sessions within 1month, was achieved in 95% (20/21) of the patients who were successfully cannulated for an overall rate of 74% (20/27). All patients who achieved functional cannulation had their central venous catheters (CVCs) removed before the 90-day follow-up for a CVC removal rate of 74% (20/27). The 4 Fr endoAVF system allowed for multiple access and fistula creation site options to tailor the procedure to individual patient anatomy. Furthermore, the outcomes are comparable to previous generation endoAVF technology, with a potentially improved safety profile because of the use of arteries at the wrist for access.

Vascular Access for Hemodialysis Patients: New Data Should Guide Decision Making.

This commentary critically examines key assumptions and recommendations in the 2006 Kidney Disease Outcomes Quality Initiative vascular access guidelines, and argues that several are not relevant to the contemporary United States hemodialysis population. First, the guidelines prefer arteriovenous fistulas (AVFs) over arteriovenous grafts (AVGs), on the basis of their superior secondary survival and lower frequency of interventions and infections. However, intent-to-treat analyses that incorporate the higher primary failure of AVFs, demonstrate equivalent secondary survival of both access types. Moreover, the lower rate of AVF versus AVG infections is counterbalanced by the higher rate of catheter-related bloodstream infections before AVF maturation. In addition, AVFs with assisted maturation (interventions before successful AVF use), which account for about 50% of new AVFs, are associated with inferior secondary patency compared with AVGs without intervention before successful use. Second, the guidelines posit lower access management costs for AVFs than AVGs. However, in patients who undergo AVF or AVG placement after starting dialysis with a central venous catheter (CVC), the overall cost of access management is actually higher in patients receiving an AVF. Third, the guidelines prefer forearm over upper arm AVFs. However, published data demonstrate superior maturation of upper arm versus forearm AVFs, likely explaining the progressive increase in upper arm AVFs in the United States. Fourth, AVFs are thought to fail primarily because of aggressive juxta-anastomotic stenosis. However, recent evidence suggests that many AVFs mature despite neointimal hyperplasia, and that suboptimal arterial vasodilation may be an equally important contributor to AVF nonmaturation. Finally, CVC use is believed to result in excess mortality in patients on hemodialysis. However, recent data suggest that CVC use is simply a surrogate marker of sicker patients who are more likely to die, rather than being a mediator of mortality.

Current state of dialysis treatment and vascular access management in Japan.

According to the data from the Japanese Society for Dialysis Therapy, the number of dialysis patients was about 330,000 at the end of 2016. The mean age of newly initiated patients was 69.4 years and that of maintenance was 68.2 years. And, diabetic nephropathy is the most common primary disease, with an incidence rate of 43.2%. These results mean that the systemic vascular condition is getting worse. In spite of these backgrounds, the patients of 97.3% were treated by hemodialysis; therefore, careful management of vascular access is essential to better maintain the condition of patients. The Dialysis Outcomes and Practice Patterns Study shows that vascular access modalities are an important factor in determining prognoses of patients and that prognosis in Japan is one of the best worldwide. In Japan, the use of arteriovenous fistulae accounts for 95% of vascular access modalities. However, a statistic by Japanese Society for Dialysis Therapy suggests that the use of arteriovenous graft has been increasing. In 2005, Japanese Society for Dialysis Therapy Guidelines recommended percutaneous transluminal angioplasty be the first choice for the treatment of vascular access stenosis. Since then, percutaneous transluminal angioplasty has become an important procedure for long-term maintenance of the morphology and function of vascular access. In Japan, approximately 60% of percutaneous transluminal angioplasty are conducted by nephrologists and urologists; in addition, arteriovenous fistulae creation procedures are also performed by them. According to my private opinion, such conditions above show that even in the absence of standardized training on vascular access management, doctors on site perform their duties in an appropriate manner. However, the problems of how we evaluate the specificity in Japan and pass it down the generations still remain.

The creation and maintenance of vascular access for chronic hemodialysis in the Moscow region: a five-year experience of a regional center

Aim:to analyze the results of the regional center for the creation and maintenance of vascular access for hemodialysis.Materials and methods.We performed a retrospective analysis. In five years (2012–2016) we performed 3,837 different operations on vascular access (VA) in 1,862 patients.Results.There is a strong dependence of type VA and the cause of CKD 5D. At the time of the HD start, the proportion of arteriovenous fistula (AVF), synthetic vascular graft (SVG) and central venous catheter (CVC) was 73.7, 0.3 and 26% for glomerulonephritis; 58.4, 0.4 and 41% for pyelonephritis; 53, 1 and 26% for diabetes mellitus; 32, 8 and 60% for polycystic disease and 33, 2 and 65% for systemic processes, respectively. After one year on HD the shares of AVF, SVG and CVC were 89, 2 and 9% for glomerulonephritis; 76, 6 and 18% of pyelonephritis; 70, 5 and 25% for diabetes mellitus; 68, 10 and 22% for polycystic disease and 53, 5 and 42% for systemic processes, respectively. In a case of start of HD via AVF, five years survival was 61% [95% CI 51.8; 71.9]; in a case of start HD via CVC with followed by conversion to AVF – 53.9% [95% CI 42.5; 67]; in a case of CVC remained the only access – 31.6% [21.4; 41.4]. Non-maturation of AVF was observed in 5.9% of new AVF (the risk increased in a case of diabetes mellitus), early thrombosis (before the first use of AVF) was observed in 12.7% of new AVF (the risk increased with diabetes, polycystic and systemic diseases). Creation of AVF a week before the start of HD or 1–2 weeks later significantly increased the risk of thrombosis. Primary patency in a year, three and five years was 77.2% (95% CI 71.7; 81.7); 48% (95% CI 41.6, 54.1); 34.1% (95% CI 27.8, 40.5) respectively; secondary patency – 87% [95% CI 83.7; 89.7]; 74.4% [95% CI 70.3; 78,12]; 60.9% [95% CI 56.4; 65.1] respectively. The use of temporary CVC is associated with a three-fold increase of the risk of infection compared with permanent CVC: IRR 3,31 (2,46; 4,43), p &lt; 0,0001.Conclusion.A more detailed analysis is required to identify risk factors for complications of vascular access and to optimize approaches to its creation and maintenance.

Predialysis nephrology care and its impact on initial vascular access type in hemodialysis patients in Jordan.

Chronic kidney disease (CKD) patients who reach end-stage renal disease (ESRD) require early nephrology referral and appropriate vascular access. Arteriovenous fistula (AVF) is the preferred access for hemodialysis (HD). Referral to nephrology of CKD patients starting HD in Jordan and its impact on AVF utilization is unknown. Patients on in-center HD in a large Jordan Ministry of Health dialysis unit were interviewed, and medical records reviewed to assess prior nephrology care and AVF use. Of 104 total patients, 93 met the inclusion criteria. The mean age was 50 ± 16 years, with 44% being females. The average body mass index was 25 ± 5. The cause of ESRD was diabetes mellitus in 28 (30%), hypertension in 28 (30%), and polycystic kidney disease in three (3%). Type of HD access at the initiation of dialysis was central venous catheter (CVC) in 80 (86%) and AVF in 12 (13%). Of the overall group, 50 (54%) were seen by nephrology before initiating dialysis, and of these, 39 patients (78%) were seen >1 year before HD initiation. Of the patients who initiated dialysis with a CVC, 38 (48%) had received prior nephrology care. All 12 patients who initiated dialysis with AVF had received prior nephrology care. Of the 50 patients who received nephrology care before dialysis initiation, 12 patients (24%) had started dialysis with an AVF; in patients without prior nephrology care, all were started with a CVC. In conclusion, our study suggests that a large percentage did not have nephrology care before initiating dialysis. The ones who were seen by nephrology before dialysis were significantly more likely to initiate dialysis using an AVF. A national focus on improving nephrology referral in advanced CKD may allow better utilization of AVF as the method of access at dialysis initiation.

Vascular access for hemodialysis: Current practice in Vietnam.

A well-functioning vascular access is a mainstay to perform an efficient hemodialysis procedure, which directly affects the quality of life in hemodialysis patients. We use three main types of access: native arteriovenous fistula, arteriovenous graft, and central venous catheter. Arteriovenous fistula remains the first and best choice for chronic hemodialysis. It is the best access for longevity, the lowest related complications, and for this reason, arteriovenous fistula use is strongly recommended by guidelines from different countries, including Vietnam. In practice, well-functioning arteriovenous fistula creation is not always simple. In this case, arteriovenous fistula creation with vein transposition or translocation is certainly useful. When native vein options have been exhausted, prosthetic can be used as the second option of maintenance hemodialysis access alternatives. Central venous catheters are very common and have become an important adjunct in maintaining patients on hemodialysis. In Bach Mai hospital, we certainly create about 1000 new arteriovenous fistulas every year (among these, about 84.98% new hemodialysis patients start hemodialysis without permanent accesses and depend on temporary central venous catheters) and successfully matured arteriovenous fistula rate is 92.6%. Among hemodialysis population in Bach Mai, 2.29% have arteriovenous grafts and 2.81% of patients still depend on cuffed tunneled catheters. The preferable locations for catheter insertions are the internal jugular and femoral veins. Proper vascular access maintenance requires integration of different professionals to create a vascular access team. Percutaneous transluminal angioplasty is not available. In our circumstance, we have achieved some advantages for hemodialysis patients but still a big gap to an advanced country.

Hemodialysis vascular access and subsequent transplantation: a report from the ESPN/ERA-EDTA Registry

BackgroundCurrent guidelines advocate use of arteriovenous fistula (AVF) over central venous catheter (CVC) for children starting hemodialysis (HD). European data on current practice, determinants of access choice and switches, patient survival, and access to transplantation are limited.MethodsWe included incident patients from 18 European countries who started HD from 2000 to 2013 for whom vascular access type was reported to the ESPN/ERA-EDTA Registry. Data were evaluated using descriptive statistics, logistic and Cox regression models, and cumulative incidence competing risk analysis.ResultsThree hundred ninety-three (55.1%) of 713 children started HD with a CVC and were more often females, younger, had more often an unknown diagnosis, glomerulonephritis, or vasculitis, and lower hemoglobin and height-SDS at HD initiation. AVF patients were 91% less likely to switch to a second access, and two-year patient survival was 99.6% (CVC, 97.2%). Children who started with an AVF were less likely to receive a living donor transplant (adjusted HR, 0.30; 95% CI, 0.16–0.54) and more likely to receive a deceased donor transplant (adjusted HR, 1.50; 95% CI, 1.17–1.93), even after excluding patients who died or were transplanted in the first 6 months.ConclusionsCVC remains the most frequent type of vascular access in European children commencing HD. Our results suggest that the choice for CVC is influenced by the time of referral, rapid onset of end-stage renal disease, young age, and an expected short time to transplantation. The role of vascular access type on the pattern between living and deceased donation in subsequent transplantation requires further study.

Gender Disparities in Vascular Access Surgical Outcomes in Elderly Hemodialysis Patients

Background: Despite national vascular access guidelines promoting the use of arteriovenous fistulas (AVF) over arteriovenous grafts (AVGs) for dialysis, AVF use is substantially lower in females. We assessed clinically relevant AVF and AVG surgical outcomes in elderly male and female patients initiating hemodialysis with a central venous catheter (CVC). Methods: Using the United States Renal Data System standard analytic files linked with Medicare claims, we assessed incident hemodialysis patients in the United States, 9,458 elderly patients (≥67 years; 4,927 males and 4,531 females) initiating hemodialysis from July 2010 to June 2011 with a catheter and had an AVF or AVG placed within 6 months. We evaluated vascular access placement, successful use for dialysis, assisted use (requiring an intervention before successful use), abandonment after successful use, and rate of interventions after successful use. Results: Females were less likely than males to receive an AVF (adjusted likelihood 0.57, 95% CI 0.52–0.63). Among patients receiving an AVF, females had higher adjusted likelihoods of unsuccessful AVF use (hazard ratio [HR] 1.46, 95% CI 1.36–1.56), assisted AVF use (OR 1.34, 95% CI 1.17–1.54), and AVF abandonment (HR 1.28, 95% CI 1.10–1.50), but similar relative rate of AVF interventions after successful use (relative risk [RR] 1.01, 95% CI 0.94–1.08). Among patients receiving an AVG, females had a lower likelihood of unsuccessful AVG use (HR 0.83, 95% CI 0.73–0.94), similar rates of assisted AVG use (OR 1.05, 95% CI 0.78–1.40) and AVG abandonment, and greater relative rate of interventions after successful AVG use (RR 1.16, 95% CI 1.01–1.33). Conclusions: While AVFs should be considered the preferred vascular access in most circumstances, clinical AVF surgical outcomes are uniformly worse in females. Clinicians should also consider AVGs as a viable alternative in elderly female patients initiating hemodialysis with a CVC to avoid extended CVC dependence.

Risk of death after first-time blood stream infection in incident dialysis patients with specific consideration on vascular access and comorbidity

BackgroundThe mortality following blood stream infection (BSI) and risk of subsequent BSI in relation to dialysis modality, vascular access, and other potential risk factors has received relatively little attention. Consequently, we assessed these matters in a retrospective cohort study, by use of the Danish nation-wide registries.MethodsPatients more than 17 years of age, who initiated dialysis between 1.1.2010 and 1.1.2014, were grouped according to their dialysis modality and vascular access. Survival was modeled in time-dependent Cox proportional hazard analyses. Potential risk factors confined by a modified Charlson comorbidity index (MCCI), were subsequently assessed in stepwise selection models.ResultsAt baseline, 764 patients received peritoneal dialysis (PD), and 434, 479, and 782 hemodialysis (HD) patients were dialyzed by use of arteriovenous fistulas (AVFs), tunneled catheters (TCs), and non-tunneled catheters (NTCs), respectively. We identified 1069 BSIs with an overall incidence rate of 17.7 episodes per 100 person years, and 216 BSIs occurred more than one time in the same patient. HRs of post BSI mortality relative to PD were 3.20 (95% CI 1.86–5.50; p < 0.001) with NTCs; whereas no associations were found for AVF and TC. The risk of subsequent BSIs was higher with NTCs [HR 2.29 (95% CI 1.09–4.82), p = 0.030], and no significant difference was found for AVF and TC, in relation to PD. There was an increased risk of both outcomes with TC relative to AVF [death: 1.57 (95% CI 1.07–2.29, P < 0.021); BSI: 1.78 (95% CI 1.13–2.83, P < 0.014], and risk of death was reduced in patients who changed to AVF after first-time BSI. The MCCI was significantly associated with the risk of subsequent BSI and post BSI death; however, only some of the variables contained in the index were found to be significant risk predictors when analyzed in the fitted model.ConclusionsWhile NTC was the most predominant risk factor for subsequent BSI and post BSI mortality, AVF appeared protective.

A new method to determine anastomosis angle configuration for arteriovenous fistula maturation.

Background: The kidneys of patients with chronic kidney disease (CKD) do not function well enough and those in end-stage renal disease (ESRD) of CKD need hemodialysis (HD) as a common renal replacement therapy (RRT) procedure. HD requires a vascular access (VA), and arteriovenous fistula (AVF) is the common VA choice in the world due to its very few complications. Despite the widespread use of AVFs, some risk factors maximize AVF failure, which is accompanied by complications of the patient such as repeating VA surgeries and hospitalization. Therefore, finding effective factors in the success of surgery is highly important and, thus, this study aimed at measuring the effect of anastomosis angle on the success of AVF surgery. Methods: This study evaluated the effect of conducted angle in an AVF anastomosis on AVF maturation. The images of 48 created AVFs for CKD patients was provided over a one-year period (from May 2016 to April 2017). Cross-tab analysis was used, and significance level was considered meaningful at p-value≤0.001. A centralized database was designed to integrate data. A method for image processing was developed and geometrical characteristics of the vessels (such as anastomosis angle) and also the diameter of artery and vein were measured via AutoCAD 2017 software and exported to the database along with other data. Results: The rate of the AVF failure in the studied patients was 8.96%. The anastomosis angle ≤ 30° is preferable from the AVF status point of view because most AVF maturation (or least AVF failure) rates are detected at this range. Conclusion: This study was performed based on a new approach without the need to measure hemodynamic parameters. Moreover, it signified the important role of anastomosis angle in the function of AVF, showing that the anastomosis angle ≤ 30° is a preferable intraoperative recommendation for AVF surgery.

Diameter Criteria Have Limited Value for Prediction of Functional Dialysis Use of Arteriovenous Fistulas

To determine the value of diameter measurements for prediction of functional dialysis use (FDU) of arteriovenous fistulas (AVF). Review of access operations and dialysis databases from January 1, 2007 to August 1, 2015. Follow up until July 1, 2016. FDU defined as six consecutive dialysis sessions with two needles on the AVF. Artery and vein diameters measured by portable ultrasound in access clinic. Contribution of diameter to predict FDU assessed with logistic regression. Diagnostic accuracy assessed by sensitivity, specificity, positive and negative predictive values (PPV and NPV). 803 AVF operations were analysed: 507 (63%) radiocephalic fistulas (RCAVF), 237 (30%) brachiocephalic fistulas (BCAVF), and 59 (7%) brachiobasilic fistulas (BBAVF). Women had lower FDU in RCAVF (0.65, 95% CI 0.58–0.72 vs 0.86, 95% CI 0.81–0.89; p < .0001), but not in BCAVF (0.83, 95% CI 0.75–0.89 vs 0.81, 95% CI 0.73–0.88; p = .75). Female gender was an independent negative predictor of FDU in RCAVF (OR 0.31; 95% CI 0.20–0.49). Vascular kidney disease was an independent negative predictor for FDU in RCAVF (OR 0.33; 95% CI 0.17–0.64) and BCAVF (OR 0.22; 95% CI 0.09–0.57) in multivariable analysis. Artery and vein diameter did not improve the model for RCAVF. Vein diameter as categorical variable improved the model for BCAVF. Diameter cut off of radial artery ≥ 2 mm has 96% sensitivity, 86% PPV, 9% specificity, and 29% NPV in men. Radial artery diameter ≥2 mm had 96% sensitivity, 67% PPV but 13% specificity and 62% NPV in women. Diameter is a poor predictor of FDU of AVF. Arterial diameter measurements add no diagnostic value for BCAVF. Poor specificity suggests a diameter under 2 mm at the wrist should not preclude AVF formation. Vascular kidney disease is an independent negative predictor for FDU in all AVF.

Effective arteriovenous fistula alternative for hemodialysis access

BackgroundThe use of autologous arteriovenous fistulae (AVF) for hemodialysis (HD) is the gold standard; however, for many patients at tertiary referral centers, this is not an option. MethodsWe conducted a four year retrospective cohort study to evaluate HD access outcomes with AVF, bovine carotid artery (BCA), and polytetrafluoroethylene arteriovenous graft (PTFE). ResultsThe study contained 416 AVF, 175 BCA, and 58 PTFE, N = 649. There was statistical difference between rates of infection (AVF 3.4%, BCA 2.9%, PTFE 11.9%), P = 0.02. Maturation failed in 7.5% of AVF but in none of the BCA or PTFE (P = 0.001). Accesses were abandoned with AVF (1.9%), BCA (1.5%), and PTFE (9.5%), P = 0.01. ConclusionBovine carotid artery can be an effective alternative form of HD access with lower infection, abandonment, and failure to maturation rates when autologous arteriovenous fistula is not an option.

Diameter Criteria Have Limited Value for Prediction of Functional Dialysis Use of Arteriovenous Fistulas

To determine the value of diameter measurements for prediction of functional dialysis use (FDU) of arteriovenous fistulas (AVF). Review of access operations and dialysis databases from January 1, 2007 to August 1, 2015. Follow up until July 1, 2016. FDU defined as six consecutive dialysis sessions with two needles on the AVF. Artery and vein diameters measured by portable ultrasound in access clinic. Contribution of diameter to predict FDU assessed with logistic regression. Diagnostic accuracy assessed by sensitivity, specificity, positive and negative predictive values (PPV and NPV). 803 AVF operations were analysed: 507 (63%) radiocephalic fistulas (RCAVF), 237 (30%) brachiocephalic fistulas (BCAVF), and 59 (7%) brachiobasilic fistulas (BBAVF). Women had lower FDU in RCAVF (0.65, 95% CI 0.58-0.72 vs. 0.86, 95% CI 0.81-0.89; p<.0001), but not in BCAVF (0.83, 95% CI 0.75-0.89 vs. 0.81, 95% CI 0.73-0.88; p=.75). Female gender was an independent negative predictor of FDU in RCAVF (OR 0.31; 95% CI 0.20-0.49). Vascular kidney disease was an independent negative predictor for FDU in RCAVF (OR 0.33; 95% CI 0.17-0.64) and BCAVF (OR 0.22; 95% CI 0.09-0.57) in multivariable analysis. Artery and vein diameter did not improve the model for RCAVF. Vein diameter as categorical variable improved the model for BCAVF. Diameter cut off of radial artery ≥ 2mm has 96% sensitivity, 86% PPV, 9% specificity, and 29% NPV in men. Radial artery diameter ≥2mm had 96% sensitivity, 67% PPV but 13% specificity and 62% NPV in women. Diameter is a poor predictor of FDU of AVF. Arterial diameter measurements add no diagnostic value for BCAVF. Poor specificity suggests a diameter under 2mmat the wrist should not preclude AVF formation. Vascular kidney disease is an independent negative predictor for FDU in all AVF.