ArticleLiterature Review

Hemodialysis access failure: A call to actionrevisited

September 2009
Kidney International 76(10):1040-8

September 2009
76(10):1040-8

DOI:10.1038/ki.2009.318

Source
PubMed

Authors:

Raymond Hakim

Vanderbilt University

Jonathan Himmelfarb

University of Washington Seattle

Eighty-two percent (82%) of patients initiating hemodialysis in the United States in 2006 did so with a catheter as the functioning access. Even in patients who have been followed by nephrologists for 6 months or more, 74% of patients initiated dialysis with a catheter. This is a multifactoral problem that requires attention and solutions from all stakeholders, including the nephrologist, the vascular surgeon, the hospital, and the insurance industry, as well as the patient and family. We propose a series of specific proposals that include a process for the timely referral and timely placement of a permanent access based on the patient's estimated or measured glomerular filtration rate (GFR), and a 'pay-for-performance' measure for vascular surgeons and nephrologists who admit patients with functional permanent accesses; such pay for performance would place a higher value for patients who are admitted with a functional arteriovenous (AV) fistula than for patients who are admitted with an AV graft. We also propose that hospitals develop a less permissive process for placement of PICC (peripherally inserted central catheters) lines in patients with GFR <60 ml/min and to consider surgery for access placement as 'urgent'. Finally, a more proactive educational process for patients and their families, including an 'informed non-consent' for patients who defer placement of a permanent access needs to be considered. The morbidity, mortality, and health-care costs associated with prolonged catheter use mandate urgent attention to this problem.

Vascular Access

Article

Full-text available

Sep 2011

Vascular Access

Article

Full-text available

Sep 2011

Hemodialysis patients are connected to life by means of vascular access. The complications of vascular access represent one of the most important causes of morbidity, mortality and high healthcare costs in the hemodialysis patients. Although it is known that the best vascular access is AVF, the fistula use rate is still low in most countries. This review will examine; association of various vascular access with morbidity, mortality and dialysis costs; different practice patterns in the world and reasons of this; finally, solutions for vascular access problems.

Fistula Eligibility: A Work in Progress

Article

Feb 2014
SEMIN DIALYSIS

Effective hemodialysis requires a reliable vascular access. Clinical practice guidelines strongly recommend the fistula as the preferred option followed by arteriovenous (AV) grafts, with central venous catheters being least preferred. Recently, there has been a growing awareness of the limitations of the fistula, its high rate of primary failure and that a fistula may not be appropriate for all patients initiating or on hemodialysis. However, determinates for fistula eligibility have not been clearly defined. The creation and use of a fistula requires the complex integration of patient, biological, and surgical factors, none of which can be easily predicted or planned. There have been several successful initiatives over the last decade addressing patient suitability for AV access, but none have validated defined criteria for fistula eligibility. We discuss these initiatives by addressing: 1) process of care, 2) radiological and nonradiological tests and procedures, and 3) alternative surgical approaches. Careful clinical judgment, appropriate vascular access assessment and placement, and an individualized approach to the risks and benefits will optimize patient health outcomes while minimizing prolonged catheter dependence among hemodialysis patients.

Vascular Access for Hemodialysis in Older Adults: A "Patient First" Approach

Article

Jun 2013
J AM SOC NEPHROL

Ann M O'Hare

In their landmark 1996 paper in JAMA, Hirth and colleagues reported that most patients in the United States with permanent vascular access were undergoing dialysis via a prosthetic graft rather than an autogenous fistula, despite known higher rates of infection and thrombosis associated with grafts.1 These authors also reported large regional differences in rates of graft use—ranging from 23% of patients with a permanent access in New England to 85% in the East South Central census region—that were not explained by variation in patient characteristics.

Functioning of an Arteriovenous Fistula Requires Heme Oxygenase-2.

Article

Full-text available

May 2013
AM J PHYSIOL-RENAL

Heme oxygenase-2 (HO-2), the constitutive isoform of the heme-degrading enzyme, heme oxygenase, may serve as an anti-inflammatory vasorelaxant, in part, by generating carbon monoxide. Arteriovenous fistulas (AVFs) are employed as hemodialysis vascular accesses because they provide an accessible, high blood flow vascular segment. We examined the role of vascular expression of HO-2 in AVF function. An AVF was created in mice by anastomosing the carotid artery to the jugular vein. HO-2 expression was detected by immunohistochemistry in the intact carotid artery, mainly in endothelial cells and smooth muscle cells; expression of HO-2 protein and mRNA was modestly increased in the artery of the AVF. Creating an AVF in HO-2(-/-) mice as compared to an AVF in HO-2(+/+) mice led to markedly reduced AVF blood flow and increased numbers of nonfunctioning AVFs. The impairment of AVF function in the setting of HO-2 deficiency could not be ascribed to either preexisting intrinsic abnormalities in endothelium-dependent and endothelium-independent relaxation of the carotid artery in HO-2 deficient mice, or to impaired vasorelaxant responses in the intact carotid artery in vivo. HO-1 mRNA was comparably induced in the AVF in HO-2(+/+) and HO-2(-/-) mice, whereas the AVF in HO-2(-/-) mice compared with that in HO-2(+/+) mice exhibited exaggerated induction of MMP-9 but similar induction of MMP-2. HO-2 deficiency also led to lower AVF blood flow when AVFs were created in uremia, the latter induced by subtotal nephrectomy. We conclude that HO-2 critically contributes to the adequacy of AVF blood flow and function.

Injerto HeRO®, una alternativa híbrida para pacientes en hemodiálisis

Article

Full-text available

May 2023

Contexto: la enfermedad renal en etapa terminal es un problema de salud pública importante. Lograr y mantener el acceso vascular a largo plazo se vuelve difícil y desafiante en aquellos pacientes en hemodiálisis como terapia de remplazo renal. El dispositivo de injerto HeRO® (Merit Medical) ha surgido como una posible solución para pacientes con opciones limitadas para hemodiálisis. Objetivo: en el presente artículo se realiza una revisión de las generalidades, las indicaciones, la costo-efectividad, las desventajas y las potenciales complicaciones de dicho dispositivo, por medio de una búsqueda de la literatura disponible hasta la fecha. Metodología: se realizó una búsqueda sistemática en la literatura de los estudios publicados sin limitación de idioma, con el fin de obtener mayor sensibilidad y arrojar mayores resultados en la búsqueda, usando las bases de datos electrónicas de Medline, Lilacs y Europe PMC hasta el 25 de agosto del 2022. Las palabras utilizadas para la búsqueda fueron “Renal Insufficiency, Chronic”, “Dialysis”, “Renal Dialysis”, “Hero Graft access Device” y “Hero graft”. Resultados: el uso del dispositivo HeRO® tiene un futuro prometedor, ya que ofrece una forma novedosa de evitar los riesgos mortales de la dependencia prolongada del catéter. Así, se requerirá de una cuidadosa selección de pacientes, experiencia y creatividad en cirugía endovascular e intervencionismo, además de un manejo experimentado por proveedores de diálisis para promover y mantener resultados de calidad. Conclusiones: los resultados de calidad a largo plazo del injerto HeRO® definirán, en última instancia, su lugar en el ámbito del acceso vascular. El dispositivo ofrece una forma novedosa de evitar los riesgos mortales de la dependencia prolongada del catéter.

Endovascular Retrieval of a Fractured Tunneled Hemodialysis Central Venous Catheter Using the Loop Snare Technique

Article

Full-text available

Feb 2023

The tunneled cuffed hemodialysis catheter is a valuable vascular access option for patients with end-stage renal disease (ESRD). Healthcare providers have become more familiar with the insertion of medical devices, including central venous catheters, in their daily practice. The occurrence of foreign body fragmentation is rare with these catheters. This article presents a case in which a fracture of the distal portion of the hemodialysis catheter was inadvertently identified during a coronary angiography. Percutaneous removal of the fractured venous catheter was performed successfully using a loop snare catheter, which prevented the patient from experiencing further complications.

Aneurysmal transformation of fistula veins: from classification to types of surgical treatment A.B. Zulkarnaev 1, B.V. Baykov 2,3, A.G. Yankov

Article

Full-text available

Jan 2020

Long-Term AVF Patency - Can we do better?

Article

Full-text available

Jun 2019

Quality assessment of vascular access procedures for hemodialysis: A position paper of the Vascular Access Society based on the analysis of existing guidelines

Article

May 2019

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.

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

Article

Full-text available

Jan 2019

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 < 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.

Self-care in Preserving the Vascular Network: Old Problem, New Challenge for the Medical Staff

Article

Full-text available

Mar 2018

Teaching/educating patients with end stage renal disease (ESRD) and identifying their self‐care behaviors for vascular network preservation are very important. However, the self‐care behaviors regularly performed by patients are still unknown. We compared self‐care behaviors for vascular network preservation performed by patients who are/are not followed‐up by the nephrologist. The study design was a prospective, observational and comparative study. Inclusion criteria were as follows: ESRD patients (at stages 4 or 5); at least 18 years old; in pre‐dialysis with at least a 6‐month follow‐up period by the nephrologist or who started dialysis in emergency and were not followed‐up by the nephrologist; with no memory problems; and medically stable. Primary outcome was the frequency of self‐care behaviors for vascular network preservation. Secondary outcome was the comparison between self‐care behaviors by ESRD patients who were/were not followed‐up by the nephrologist. The study involved 145 patients, 64.1% were female, the mean age was 69.5 years and the self‐care behaviors mean score was 36.8% (with a SD of 39.8%). The number of patients followed‐up and not followed‐up by the nephrologist was 109 (group 1) and 36 (group 2), respectively. Social characteristics were similar in the two groups (P > 0.05). The mean self‐care behaviors were 29.4% and 59.2% in groups 1 and 2, respectively (P = 0.000). Patients performed self‐care behaviors for vascular network preservation with a relatively low frequency (the mean score was 36.8% only). Patients not followed by the nephrologist performed self‐care behaviors more often than those who were followed (59.2% vs. 29.4% respectively, P = 0.000).

Clinical Course of Hemodialysis Access After Initial Endovascular Intervention for Stenosis in Asian Renal Failure Patients

Article

May 2017

Background: Arteriovenous fistula (AVF) and arteriovenous fistula graft (AVG) access for hemodialysis can develop stenosis, eventually leading to thrombosis and access failure. Prompt endovascular intervention can salvage the access but restenosis does occur. Clinical course, restenosis pattern, and risk factors associated with initial stenosis of AVFs/AVGs in Asian hemodialysis patients were studied. Method: A retrospective study was conducted (January 2009-June 2012) on consecutive patients with renal failure who developed the first-time stenosis in the vascular access and were managed with endovascular intervention. One hundred fourteen patients (54 AVFs and 60 AVGs) were studied, and all clinical outcomes were recorded until October 2013. Results: The mean time from access creation to endovascular intervention for the first-time stenosis for patients with AVF and AVG was 23.5 (32.7 standard deviation [SD]) months and 12.5 (11.0) months, respectively. An average of 1.7 (range, 1-5) interventions were performed for AVFs, whereas 2.4 (range, 1-11) for AVGs ( P = .008). Upon conclusion of the study, 23 patients with AVF survived with functional index access, whereas 10 passed away with a functional original access. The remaining 21 patients with AVFs failed, requiring new access, tunneled catheter, or peritoneal dialysis. Of the 60 patients with AVG, 6 survived and 8 died with functional index access; 46 required new access or other forms of dialysis ( P = .000). Kaplan-Meier estimated that access patency and survival with functional access were significantly lower for AVGs than for AVFs after the first salvage intervention. Female patients had an increased risk of restenosis with both univariate ( P = .016) and multivariate ( P = .013) analysis. With univariate analysis ( P = .039), patients with hyperlipidemia had a higher risk of developing restenosis in the vascular access. Conclusion: The clinical course and prognosis of failing AVFs and AVGs are distinct. The information on access prognosis and stenosis recurrence patterns will be helpful for patient counseling and planning of follow-up intervals, after the first-time intervention for access stenosis.

Basilic vein transposition: A viable alternative for multiple failed arteriovenous fistulas - A single center experience

Article

Full-text available

Mar 2017

Primary use of the autogenous arteriovenous access is recommended by the National Kidney Foundation-Dialysis Outcomes Quality Initiative guidelines. In spite of troublesome comorbidities associated with basilic vein transposition (BVT), it is still the most preferred technique when autologous veins are not suitable to construct radio-cephalic fistula (RCF) and brachiocephalic fistula (BCF), arteriovenous fistula (AVF). The present study highlights our experience with BVT, with small incision technique, over a period of two years with excellent outcome. This retrospective study included all the patients who underwent BVT at our tertiary care center between March 2013 and March 2015. It was performed in patients with failed previous RCF or BCF or who had small caliber or thrombosed cephalic veins. The patients with minimum 3 mm basilic vein diameter on Doppler were only included in the study. A 3-cm horizontal incision was made in antecubital fossa to expose brachial artery and basilic vein. Multiple longitudinal separate second skin incisions (2–3 cm) were made to explore proximal part of basilic vein. Side branches of the vein were isolated and ligated. The divided basilic vein in antecubital fossa was brought over fascia through newly created subcutaneous tunnel followed by end-to-side anastomosis. A total of 18 (12 males and 6 females) underwent BVT in the two years period. The mean fistula maturation time was 42 ± 10 days. Maturation rate was 100%, and the postoperative flow rate was 290 ± 22 (mL/min). No bleeding, thrombosis, failure, pseudo aneurysm, or rupture occurred in our patients. Arm edema occurred in ix (33%) patients, infection in three (17%), and lymphorrhea in five (28%). The mean follow-up was six months. BVT is an alternative method with excellent initial maturation and functional patency rates requiring less extensive skin incision and surgical dissection. It is the most durable hemodialysis access procedure for those patients having multiple forearm AVF surgeries.

Preparation of the Dialysis Access in Stages 4 and 5 CKD

Article

Jul 2016

Patients with Stages 4 and 5 CKD are optimally managed within a multidisciplinary care setting. This provides an opportunity to create a “patient centered” approach to renal replacement modality options and conservative care. The care team engages with the patient and caregivers to assist with the understanding of their health status, modality and vascular access selection, and overall living with the comorbidity of chronic illness. A systematic approach to provision of education, modality, and access selection, are in part, driven by the patient's expected survival and need for dialysis, the risks and benefits with different modalities, and access and adaptation to their preferences and home situations. Dialysis access education should be included in all education programs so that patients can consider risks and benefits of all modalities. Decision support interventions have been effective in reducing decisional conflict and informed values–based decision-making. For both hemodialysis and peritoneal dialysis, timing of the surgical referral and access creation should be individualized based on the rate of CKD progression, risk of complications, and ease of access to surgical services. The health care team should support the patients' decision balancing risks and benefits, as well as their lifestyle, values, beliefs, and preferences.

Quality of current management form of vascular access in hemodialysis patients

Article

Full-text available

Apr 2012
Rev Cubana Med

Backgrounds: the follow-up of the quality indicators is associated with a great survival, less need of hospitalization and less hemodialysis costs. Objective: to assess the quality of the current management form of the vascular access in hemodialysis patients. Methods: a prospective and descriptive study was conducted in a universe including the patients incorporated into the hemodialysis plan of the Hermanos Ameijeiras: Clinical Surgical Hospital from June, 2010 to May, 2011. Authors assessed the indicators of the care quality of vascular access for hemodialysis taking as reference the recommendation of the Group of Quality Management of the Spanish Society of Nephrology and the guidelines K/DOQI. Results: the temporary vascular access is related to the background of infections from vascular access. It is significant the relationship between the type of vascular access, the backgrounds of infections related to it and mortality. Assessing the quality parameters it was noted that the percentage of incident patients with standing vascular access was of 37,5 %. The yearly rate of thrombosis of arteriovenous fistula was of 0,12. The percentage of infections in tunneled catheters and that of the arteriovenous fistula in one year were very high to that recommended. There was not a report on incidence of complications related to catheter insertion. Conclusions: it is necessary the transformation of the current quality management system, the increase of the control on the activity performed and the implementation of corrective actions.

Factors Affecting Hemodialysis Adequacy in Cohort of Iranian Patient with End Stage Renal Disease

Article

Full-text available

Dec 2015

Background: There are many factors that can affect dialysis adequacy; such as the type of vascular access, filter type, device used, and the dose, and rout of erythropoietin stimulation agents (ESA) used. The aim of this study was investigating factors affecting Hemodialysis adequacy in cohort of Iranian patient with end stage renal disease (ESRD). Methods: This is a cross-sectional study conducted on 133 Hemodialysis patients referred to two dialysis units in Sistan-Baluchistan province in the cities of Zabol and Iranshahr, Iran. We have looked at, (the effects of the type of vascular access, the filter type, the device used, and the dose, route of delivery, and the type of ESA used) on Hemodialysis adequacy. Dialysis adequacy was calculated using kt/v formula, two-part information questionnaire including demographic data which also including access type, filter type, device used for hemodialysis (HD), type of Eprex injection, route of administration, blood groups and hemoglobin response to ESA were utilized. The data was analyzed using the SPSS v16 statistical software. Descriptive statistical methods, Mann-Whitney statistical test, and multiple regressions were used when applicable. Results: The range of calculated dialysis adequacy is 0.28 to 2.39 (units of adequacy of dialysis). 76.7% of patients are being dialyzed via AVF and 23.3% of patients used central venous catheters (CVC). There was no statistical significant difference between dialysis adequacy, vascular access type, device used for HD (Fresenius and B. Braun), and the filter used for HD (p> 0.05). However, a significant difference was observed between the adequacy of dialysis and Eprex injection and patients’ time of dialysis (p <0.05). Conclusion: Subcutaneous ESA (Eprex) injection and dialysis shift (being dialyzed in the morning) can have positive impact on dialysis adequacy. Patients should be educated on the facts that the type of device used for HD and the vascular access used has no significant effects on dialysis adequacy.

Calidad del modelo de gestión actual del acceso vascular en los pacientes en hemodiálisis

Article

Full-text available

Jun 2012
Rev Cubana Med

Backgrounds: the follow-up of the quality indicators is associated with a great survival, less need of hospitalization and less hemodialysis costs. Objective: to assess the quality of the current management form of the vascular access in hemodialysis patients. Methods: a prospective and descriptive study was conducted in a universe including the patients incorporated into the hemodialysis plan of the "Hermanos Ameijeiras: Clinical Surgical Hospital from June, 2010 to May, 2011. Authors assessed the indicators of the care quality of vascular access for hemodialysis taking as reference the recommendation of the Group of Quality Management of the Spanish Society of Nephrology and the guidelines K/DOQI. Results: the temporary vascular access is related to the background of infections from vascular access. It is significant the relationship between the type of vascular access, the backgrounds of infections related to it and mortality. Assessing the quality parameters it was noted that the percentage of incident patients with standing vascular access was of 37,5 %. The yearly rate of thrombosis of arteriovenous fistula was of 0,12. The percentage of infections in tunneled catheters and that of the arteriovenous fistula in one year were very high to that recommended. There was not a report on incidence of complications related to catheter insertion. Conclusions: it is necessary the transformation of the current quality management system, the increase of the control on the activity performed and the implementation of corrective actions.

Catheter last fistula first

Article

Full-text available

May 2012
SEMIN DIALYSIS

Joseph A Vassalotti

Cardiac Arrest Secondary to Bilateral Pulmonary Emboli following Arteriovenous Fistula Thrombectomy: A Case Report with Review of the Literature

Article

Full-text available

May 2012

Number of patients with End Stage Renal Disease (ESRD) is growing worldwide. Hemodialysis remains the main modality of renal replacement therapy for ESRD patients. A patent hemodialysis access (arteriovenous fistula or arteriovenous graft) plays a key role in successful delivery of hemodialysis. Common vascular access issues encountered by patients and nephrologists are thrombosis and infection. The thrombosed access is declotted by various percutaneous techniques these days by multiple outpatient access centers in a timely fashion. Thrombolysis can give rise to various complications, a few of which can be life threatening. A young hemodialysis patient underwent percutaneous thrombolysis of his clotted arteriovenous fistula. Outpatient access thrombectomy was complicated immediately afterwards with cardiac arrest requiring cardiac resuscitation in the recovery room. The patient was admitted to intensive care unit after life sustaining care. Work up revealed multiple pulmonary emboli to both lung fields on CT scan of the chest. Patient was anticoagulated and discharged from the hospital. Thrombolysis of clotted hemodialysis access is associated commonly with occurrences of pulmonary embolic which are usually asymptomatic. Massive pulmonary embolization due to access thrombolysis is rare. Nephrologists and radiologists should be aware of this dangerous complication particularly in patients with preexisting cardiopulmonary disease.

Advanced vascular access workshop for dialysis nurses: A three-year review

Article

Full-text available

Jun 2012

Smith, V. (2012). Advanced vascular access workshop for dialysis nurses: a three-year review. Renal Society of Australasia Journal, 8(2), 89-93. Abstract There is increased awareness regarding the benefits of ultrasound for vascular access surveillance and guided cannulation in haemodialysis. However, finding time to train staff whilst working within the clinical setting is challenging. In 2009 a workshop was introduced in Victoria to provide a platform for nursing staff to learn advanced skills in surveillance and cannulation in a safe, supportive environment. The workshop covered topics such as: assessment and cannulation; surgical perspectives in vascular access; radiological perspectives in vascular access; surveillance and monitoring; cannulation competency package; antegrade/ antegrade cannulation; and introduction to ultrasound plus five hours of practical sessions. Feedback from the workshop over the past three years has been positive, and staff have benefited from the both the theoretical and clinical components of the workshop. The success of this workshop highlights the demand for continuing education within the renal workforce.

Uremic Serum and Solutes Increase Post-Vascular Interventional Thrombotic Risk Through Altered Stability of Smooth Muscle Cell Tissue Factor

Article

Dec 2012
CIRCULATION

Background: Stent thrombosis (ST), a postinterventional complication with a mortality rate of 50%, has an incidence that rises precipitously in patients at risk. Chronic renal failure and end-stage renal disease have emerged as particularly strong ST risk factors, yet the mechanism remains elusive. Tissue factor (TF) is a crucial mediator of injury-related thrombosis and has been implicated for ST. We posit that uremia modulates TF in the local vessel wall to induce postinterventional thrombosis in patients with end-stage renal disease. Methods and results: As a model of the de-endothelialized, postinterventional state, we exposed primary human vascular smooth muscle cells (vSMCs) pretreated with uremic serum (obtained from ESRD patients on hemodialysis) to coronary-like blood flow. vSMC TF expression, activity, stability, and posttranslational modification were examined after vSMCs were treated with uremic serum or solutes. We found significantly greater clot formation after uremic serum exposure, which was substantially reduced with the prior treatment with anti-TF neutralizing antibody. Uremic sera induced 2- to 3-fold higher TF expression and activity in vSMCs independent of diabetes mellitus. Relevant concentrations of isolated uremic solutes such as indole-3-acetic acid (3.5 μg/mL), indoxyl sulfate (25 μg/mL), and uric acid (80 μg/mL) recapitulated these effects in cell culture and the flow loop model. We show further that TF undergoes ubiquitination at baseline and that uremic serum, indole-3-acetic acid, and indoxyl sulfate significantly prolong TF half-life by inhibiting its ubiquitination. Conclusions: The uremic milieu is profoundly thrombogenic and upregulates vSMC TF levels by increasing TF stability and decreasing its ubiquitination. Together, these data demonstrate for the first time that the posttranslational regulation of TF in uremia may have a causative role in the increased ST risk observed in uremic patients. These data suggest that interventions that reduce vSMC TF may help to prevent ST and that uremic solutes should be considered as novel risk factors for ST in patients with chronic renal failure.

Factors associated with suboptimal initiation of dialysis despite early nephrologist referral

Article

Dec 2012
NEPHROL DIAL TRANSPL

BackgroundSTARRT recently demonstrated that many patients experience suboptimal dialysis starts (defined as initiation as an inpatient and/or with a central venous catheter), even when followed by a nephrologist for >12 months (NDT 2011). However, STARRT did not identify the factors associated with suboptimal initiation of dialysis. The objectives of this study were to extend the results of STARRT by ascertaining the factors leading to suboptimal initiation of dialysis in patients who were referred at least 12 months prior to commencement of dialysis.Methods At each of the three Toronto centers, charts of consecutive incident RRT patients were identified from 1 January 2009 to 31 December 2010, with predetermined data extracted.ResultsA total of 436 incident RRT patients were studied; 52.4% were followed by a nephrologist for >12 months prior to the initiation of dialysis. Suboptimal starts occurred in 56.4% of these patients. No attempt at arteriovenous fistula (AVF) or arteriovenous graft (AVG) prior to initiation was made in 65% of these starts. Factors contributing to suboptimal starts despite early referral included patient-related delays (31.25%), acute-on-chronic kidney disease (31.25%), surgical delays (16.41%), late decision-making (8.59%) and others (12.50%). The percentage of optimal starts with early referral among 14 nephrologists ranged from 33 to 72%.Conclusions Most patients started dialysis in a suboptimal manner, despite an extended period of pre-dialysis care. Nephrologists should take responsibility for suboptimal initiation of dialysis despite early referral and test methods that attempt to prevent this.

Balloon-Assisted Maturation (BAM) of the Arteriovenous Fistula: The Good, the Bad, and the Ugly

Article

Nov 2012

Arteriovenous fistula (AVF) maturation failure is currently a huge clinical problem. One approach to enhance the AVF maturation rate is an aggressive sequence of balloon angioplasty procedures, often known as balloon-assisted maturation. The goal of the current paper is to explore the pros and cons of this procedure and to try and better identify its impact on AVF maturation.

Fistula First Breakthrough Initiative: Targeting Catheter Last in Fistula First

Article

Full-text available

Apr 2012
SEMIN DIALYSIS

An arteriovenous fistula (AVF) is the optimal vascular access for hemodialysis (HD), because it is associated with prolonged survival, fewer infections, lower hospitalization rates, and reduced costs. The AVF First breakthrough initiative (FFBI) has made dramatic progress, effectively promoting the increase in the national AVF prevalence since the program's inception from 32% in May 2003 to nearly 60% in 2011. Central venous catheter (CVC) use has stabilized and recently decreased slightly for prevalent patients (treated more than 90 days), while CVC usage in the first 90 days remains unacceptably high at nearly 80%. This high prevalence of CVC utilization suggests important specific improvement goals for FFBI. In addition to the current 66% AVF goal, the initiative should include specific CVC usage target(s), based on the KDOQI goal of less than 10% in patients undergoing HD for more than 90 days, and a substantially improved initial target from the current CVC proportion. These specific CVC targets would be disseminated through the ESRD networks to individual dialysis facilities, further emphasizing CVC avoidance in the transition from advanced CKD to chronic kidney failure, while continuing to decrease CVC by prompt conversion of CVC-based hemodialysis patients to permanent vascular access, utilizing an AVF whenever feasible.

Reassessing the utility of access recirculation and Kt/V for the prediction of arteriovenous fistula failure using online clearance monitoring: the SHUNT STUDY

Article

Nov 2022
J NEPHROL

Background The arteriovenous fistula (AVF) is prone to thrombosis which can be avoided by use of monitoring and surveillance programmes. Although surveillance imaging techniques have been shown to be more sensitive and specific than clinical monitoring during dialysis, monitoring may have significant advantages in terms of cost and time saving. In this study we evaluate the yield of two monitoring techniques [blood temperature monitoring (BTM) access recirculation (AR) and Kt/V via online-clearance-monitoring (OCM)].Methods In this single-centre prospective observational study, 101 patients were followed-up for one year. The primary outcome measure was a composite of AVF failure. OCM-Kt/V and BTM-AR were recorded at every dialysis session.ResultsOf all baseline characteristics only a prior history of percutaneous transluminal angioplasty (PTA) to the AVF conferred a significant change in AVF survival (failure events/100 pt years with prior PTA vs. without = 64.0 vs. 17.3, log-rank p = 0.0014; unadjusted hazard ratio (HR) 3.74 (95% CI 1.56–8.94) p = 0.003). Participants with baseline AR < 10% vs. > 15% had poorer AVF survival (p = 0.0002) and HR for baseline AR 10–15% group vs. AR > 15% group = 4.5 (95% CI 1.55–13.05). There was no combination of change in (Δ) AR, ΔKt/V or its presence over any number of dialysis sessions that provided an acceptable combination of sensitivity and specificity or discrimination for AVF failure.ConclusionsBTM-AR and OCM-Kt/V are specific but insufficiently sensitive tools for the prediction of AVF failure. BTM-AR and OCM-Kt/V use at every dialysis session appears to add little to the traditional, infrequent use of these evaluations.

Patient-Type Bayes-Adaptive Treatment Plans

Article

Feb 2021

Treatment decisions that explicitly consider patient heterogeneity can lower the cost of care and improve outcomes by providing the right care for the right patient at the right time. “Patient-Type Bayes-Adaptive Treatment Plans” analyzes the problem of designing ongoing treatment plans for a population with heterogeneity in disease progression and response to medical interventions. The authors create a model that learns the patient type by monitoring patient health over time and updates a patient's treatment plan according to the information gathered. The authors formulate the problem as a multivariate state space partially observable Markov decision process (POMDP). They provide structural properties of the optimal policy and develop several approximate policies and heuristics to solve the problem. As a case study, they develop a data-driven decision-analytic model to study the optimal timing of vascular access surgery for patients with progressive chronic kidney disease. They provide further policy insights that sharpen existing guidelines.

Getting the basics right: the monitoring of arteriovenous fistulae, a review of the evidence

Article

Sep 2020
CURR OPIN NEPHROL HY

Purpose of review: Despite being the preferred vascular access for haemodialysis, the arteriovenous fistula (AVF) remains prone to a number of complications, the most common of these being thrombosis secondary to stenosis. This has resulted in the widespread use of monitoring and surveillance programmes. Surveillance uses more resources than monitoring and has not been convincingly shown to improve outcomes. The evidence supporting the use of the various monitoring tools has been relatively neglected and has not been the focus of literature review. This narrative review is the first to appraise the evidence for the use of physical examination, access recirculation, Kt/V and dynamic venous pressures (DVP) as monitoring tools in mature AVF. Recent findings: The vastly increased number of data points for access recirculation, Kt/V and DVP produced as standard by online clearance monitoring (OCM) on modern dialysis machines is likely to have significantly changed the utility of these metrics in the prediction of AVF failure. Algorithms have been developed to highlight those of highest risk of failure. Summary: The evidence supporting the use of monitoring in the prediction of AVF failure is predominantly observational, underpowered and more than 20 years old. Access recirculation and Kt/V appears to have higher utility in AVF than in arteriovenous grafts. We suggest that the development of OCM necessitates the reevaluation of these tools.

The role of the vascular surgeon in improvement of organization of dialysis help

Article

Jan 2019

Analysed herein are one-year results of formation of arteriovenous fistulas in 109 patients with end-stage chronic renal failure, as well as therapeutic decision-making after angiosurgical counselling of 144 patients presenting with 'problem' permanent vascular accesses. The counselling and formation of arteriovenous fistulas were carried out in conditions of interdepartmental collaboration between outpatient centres dealing with haemodialysis and vascular surgeons specialized in ultrasound mapping of peripheral vessels and performing different variants of arteriovenous fistulas. The angiosurgical care was as close to the patient as possible. Of the 109 operated patients, primary arteriovenous fistulas were made in 46 (42.2%) cases, secondary AVF - in 27 (24.8%) cases, and reconstruction of AVF - in 36 (33.0%) cases. Of the 144 patients with 'problem' permanent vascular assesses, correction of arteriovenous fistulas turned out impossible in 13 (9.1%). In the remaining 131 (90.9%) patients there was a possibility of different variants of open reconstruction of arteriovenous fistulas or performing angioplasty. Active policy of vascular surgeons in interdepartmental collaboration with nephrologists made it possible to bridge over the difficulties of patients routing which resulted in reduction of the terms of formation of arteriovenous fistulas by 2 months. Preventive arteriovenous fistulas were carried out in 17.4% of cases of primary permanent vascular assesses. During a year after formation of permanent vascular accesses, the number of patients with vascular catheters in ambulatory centres decreased from 22 to 17%. These positive changes in organization of the dialysis treatment made it possible to reduce the risks of infectious complications, to obtain adequate blood flow characteristics for haemodialysis procedures, as well as to decrease financial expenses and labour costs for AVF care.

BASILIC VEIN TRANSPOSITION FOR MULTIPLE FAILED ARTERIOVENOUS FISTULAS - OUR EXPERIENCE

Article

Full-text available

Jan 2018

BACKGROUND The National Kidney Foundation- Dialysis Outcomes Quality Initiative Guidelines recommend primary use of autogenous arteriovenous access in patients of chronic renal failure waitlisted for haemodialysis. In spite of troublesome comorbidities associated with BVT, it is still the most preferred technique when autologous veins are not available to construct radiocephalic or brachiocephalic fistula. The present study highlights our experience with BVT with small incision technique over a period of three years with excellent outcome. MATERIALS AND METHODS This retrospective study included all the patients who underwent BVT at our tertiary care center between August 2013 and August 2016. It was performed in patients with failed previous RCF or BCF or who had small caliber or thrombosed cephalic veins. The patients with minimum 3 mm basilic vein diameter on Doppler were only included in the study. A 3-cm horizontal incision was made in antecubital fossa to expose brachial artery and basilic vein. Multiple longitudinal separate second skin incisions (2-3 cm) were made to explore proximal part of basilic vein. Side branches of the vein were isolated and ligated. The divided basilic vein in antecubital fossa was brought over fascia through newly-created subcutaneous tunnel followed by endto-side anastomosis. RESULTS A total of 30 (20 males and 10 females) underwent BVT in the three years period. The mean fistula maturation time was 40 ± 10 days. Maturation rate was 100% and the postoperative flow rate was 280 ± 22 (mL/min.). No bleeding, thrombosis, failure, pseudoaneurysm or rupture occurred in our patients. Arm oedema occurred in 6 (20%) patients, infection in 4 (13%) and lymphorrhoea in 5 (17%). The mean follow-up was six months. CONCLUSION BVT is an alternative method with excellent initial maturation and functional patency rates requiring less extensive skin incision and surgical dissection. It is the most durable haemodialysis access procedure for those patients having multiple forearm AVF surgeries.

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

Article

Jul 2017

Timmy Lee

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

La adventicia arterial: actor olvidado del sistema cardiovascular

Article

Full-text available

Apr 2015

Actualmente se acepta que la adventicia tiene: un importante rol fisiológico al determinar el nivel de nutrición, oxigenación, reparación arterial, regulación de la vasomotricidad, control de la poscarga ventricular, control de la función arterial, etcétera, a la vez que tiene una importante participación en procesos patológicos (por ejemplo, aterosclerosis, hipertensión arterial, génesis de aneurismas de aorta abdominal). Sin embargo, dado lo reciente de la mayoría de los estudios que han redefinido el rol de la adventicia, aún persiste mucho desconocimiento en la comunidad biomédica acerca de la fisiología de la capa adventicia arterial. El presente trabajo tiene como objetivo revisar el rol que actualmente se reconoce para la capa adventicia de la pared arterial.

The Natural History of Hemodialysis Access

Chapter

Nov 2017

Fionnuala C. Cormack

One of the most critical aspects of planning for long-term hemodialysis (HD) is obtaining vascular access. Hemodialysis access had evolved over the years and this chapter discusses the history of hemodialysis in the USA.

The importance of success prediction in angioaccess surgery

Article

Full-text available

Sep 2016
INT UROL NEPHROL

Access to the circulation is an “Achilles’ heel” of chronic hemodialysis. According to the current guidelines, autologous arteriovenous fistula is the best choice available. However, the impossibility of immediate use and the high rate of non-matured fistulas place fistula far from an ideal hemodialysis vascular access. The first attempt at constructing an angioaccess should result in functional access as much as possible. After failed attempts, patients and nephrologists lose their patience and confidence, which results in high percentage of central venous catheter use. Predictive models could help, but clinical judgment still remains crucial. Early referral to the nephrologist and vascular access surgeon, careful preoperative examinations, preparation of patients and duplex sonography mapping of the vessels are very important in the preoperative stage. In the operative stage, it is crucial to understand that angioaccess procedures should not be considered as minor procedures and these operations must be performed by surgeons with demonstrable interest and experience. In the postoperative stage, appropriate surveillance of the maturation process is also important, as well as good cannulation skills of the dialysis staff. The purpose of this review article is to stress the importance of success prediction in order to avoid unsuccessful attempts in angioaccess surgery.

Effect of a Rapid Clinical Protocol to the Conversion from Central Venous Hemodialysis Catheter to Arteriovenous Access

Article

Dec 2015
J Vasc Access

Purpose: Evaluation of the rapid conversion protocol that includes an ambulatory dialysis access center (DAC), and a three-step clinical pathway, to the conversion rate from central venous hemodialysis (HD) catheter to functioning arteriovenous (AV) access. Methods: Prospective data were collected on 97 consecutive catheter-dependent HD patients. DAC is defined as an ambulatory unit, able to accommodate clinic visits, ultrasound examinations, surgical, interventional and hybrid procedures. Step I: initial evaluation, vein mapping and creation of AV access. Step II: clinical evaluation in two weeks and if failure identified, secondary procedure to restore function. Step III: evaluation in four weeks after creation, and additional procedure to promote maturation if indicated. The success rate, time to conversion and time to catheter removal were recorded. Results: From the 97 consecutive referred patients, eight patients were excluded. From the remaining 89 patients, 99% were successfully converted to AV access. Seventy-three percent of the patients were converted to native arteriovenous fistulae and 27% of the patients to prosthetic arteriovenous shunts. The median time from creation to HD catheter removal was 63 (SD 41) days. Fifty-two percent of the patients required at least one additional secondary procedure to accomplish successful conversion. Conclusions: High rates of timely conversion from catheter to AV access, primarily AV fistulae, can be accomplished within the context of the rapid conversion protocol.

Hemodialysis

Article

Jan 2012

M.V. Rocco

Vascular access for incident hemodialysis patients in Catalonia: analysis of data from the Catalan Renal Registry (2000-2011)

Article

Sep 2015
J Vasc Access

Purpose: Arteriovenous fístula is the best vascular access (VA) for hemodialysis. We analyzed the VA used at first session and the factors associated with the likelihood to start hemodialysis by fistula in 2000-2011. Methods: Data of VA type were obtained in 9,956 incident hemodialysis patients from the Catalan Registry. Results: Overall, 47.9% of patients initiated hemodialysis with a fistula, 1.2% with a graft, 15.9% with a tunneled catheter and 35% with an untunneled catheter. The percentage of incident patients with fistula and catheter has remained stable at around 50% over the years. The likelihood to start hemodialysis with fistula was significantly lower in females [adjusted odds ratio: 0.69, 95% confidence interval (CI): 0.61-0.75], patients aged 18-44 years (0.78, 95% CI: 0.64-0.94), patients with comorbidity (0.67, 95% CI: 0.60-0.75) and tended to be lower in patients aged over 74 years (0.89, 95% CI: 0.78-1.01). The probability to use fistula was significantly higher in patients with polycystic kidney disease (2.08, 95% CI: 1.63-2.67), predialysis nephrology care longer than 2 years (4.14, 95% CI: 3.63-4.73) and steady chronic kidney disease (CKD) progression (10.97, 95% CI: 8.41-14.32). During 1 year of follow-up, 67.2% and 59.6% of patients using untunneled and tunneled catheter changed to fistula, respectively. Conclusions: Starting hemodialysis by fistula was related with nonmodifiable patient characteristics and modifiable CKD practice processes, such as predialysis care duration. Half of the incident patients were exposed annually in Catalonia to potential catheter complications. This scenario can be improved by optimizing the processes of CKD care.

Optimal Vascular Access Choice for Patients on Hemodialysis

Article

Aug 2015

Which vascular access to use is considered one of the most important questions in the care of patients on hemodialysis (HD). An arteriovenous fistula (AVF) is often considered the gold standard for delivering HD due to better patient survival, higher quality of life, and fewer complications. However, AVFs have some limitations: they require surgery, it takes approximately three months to know whether the surgery was successful, and a majority of these surgeries end in failure. Conversely, another common vascular access, the central venous catheter, can be inserted via a simple procedure and used immediately after placement. In this research, we address the question of whether and when to perform AVF surgery on incident and established HD patients, with the aim of finding individualized policies that maximize a patientâ€™s probability of survival and remaining quality-adjusted life expectancy. Using a continuous-time dynamic programming model and under certain data-driven assumptions, we establish structural properties of the optimal policy for each objective. We provide further insights for policy makers through our numerical experiments.

Successful Access Rate and Risk Factor of Vascular Access Surgery in Arm for Dialysis

Article

Full-text available

Mar 2014

Preservation of adequate vascular access is of vital importance for patients undergoing chronic dialysis in renal failure. The aim of this study is to evaluate the successful access rate and risk factors of arteriovenous fistula (AVF) in the arm for dialysis at a single center. Patients undergoing vascular access operation between January 2006 and December 2011 were retrospectively identified. A total of 362 vascular access operations were performed. There were 338 autologous AVFs (93.4%) and 24 prosthetic grafts (6.6%). Men comprised 58.3% of all subjects. Mean age was 59.5±14.7 years. There were 187 diabetes mellitus patients (51.7%). There was a mean duration of 70.3±21.1 days between access creation to first cannulation. Overall successful access rate for dialysis was 95.9%. Of 338 autologous AVFs, 326 patients had patent AVFs for dialysis (96.4% surgical success rate), while 21 of 24 prosthetic grafts were patent (87.5% surgical success rate). A total of 141 patients (38.9%) came to surgery with preoperative central venous catheters (CVC) of which 130 (35.9%) AVFs had a patent fistula in the arm. The only risk factor related to successful access rate of AVF was preoperative CVC placement (P=0.012). Successful vascular access rate was 95.9%. The only risk factor related to patent access of AVF was preoperative CVC placement. At least 6 months prior to expected dialysis, AVF surgery is recommended, which may overcome the challenge of co-morbid conditions from having a preoperative CVC.

Examining Hemodialysis Reliable Outflow catheter performance and cost in hemodialysis access

Article

Mar 2014

Background: The Hemodialysis Reliable Outflow (HeRO) vascular access device is a hybrid polytetrafluoroethylene graft-stent construct designed to address central venous occlusive disease. Although initial experience has demonstrated excellent mid-term patency rates, subsequent studies have led to external validity questions. The purpose of this study was to examine a single center experience with this vascular access device in challenging access cases with associated costs. Methods: A retrospective study representing the authors' cumulative HeRO vascular access device experience was undertaken. The primary endpoint was graft failure or death, with secondary endpoints including secondary intervention rates and cost. Results: Forty-one patients with 15,579 HeRO days and a mean of 12.7 ± 1.5 mo with the vascular access device were available for analysis. Secondary patency was 81.6% at 6 mo and 53.7% at 12 mo. The reintervention rate was 2.84 procedures per HeRO vascular access device year. Associated HeRO costs related to subsequent procedures were estimated at $34,713.63 per patient/y. Conclusions: These data on the patency and primary outcome data diverge significantly from initial multicenter studies and represent a real-world application of this technology. It is costly to maintain patency. Use of HeRO vascular access devices should be judicious with outcome expectations reduced.

Proliferation Patterns in a Pig Model of AV Fistula Stenosis: Can we Translate Biology into Novel Therapies?

Article

May 2014
SEMIN DIALYSIS

Arteriovenous fistula (AVF) stenosis remains an important cause of AVF maturation failure for which there are currently no effective therapies. To understand the mechanisms involved, we have examined the pattern of cellular proliferation at different time points in a pig model of AVF stenosis. Immunohistochemical analysis of cellular proliferation was performed at 2, 7, 28, and 42 days. The distribution of cellular proliferation within the different layers of the vessel wall was also studied. An ANOVA analysis was used to identify differences between the magnitude of cellular proliferation at different time points and within different layers of the vessel wall. Adventitial proliferation occurred at 2 days and declined over time. Intimal and medial proliferation peaked at 7 days and then decreased over time. There was minimal proliferation in all three layers at the 28- and 42-day time points. An important finding was the presence of active myofibroblast proliferation within "neointimal buds" at the 7-day time point. Results suggest that there could be early adventitial activation, followed by a passage of these cells into the medial and intimal layers. These suggest that the application of perivascular antiproliferative (adventitial) therapies at the time of surgery could potentially reduce AVF maturation failure.

Hemodialysis Catheter Care Strategies: A Cluster-Randomized Quality Improvement Initiative

Article

Nov 2013
AM J KIDNEY DIS

The prevalence of central venous catheters (CVCs) for hemodialysis remains high and, despite infection-control protocols, predisposes to bloodstream infections (BSIs). Stratified, cluster-randomized, quality improvement initiative. All in-center patients with a CVC within 211 facility pairs matched by region, facility size, and rate of positive blood cultures (January to March 2011) at Fresenius Medical Care, North America. Incorporate the use of 2% chlorhexidine with 70% alcohol swab sticks for exit-site care and 70% alcohol pads to perform "scrub the hubs" in dialysis-related CVC care procedures compared to usual care. The primary outcome was positive blood cultures for estimating BSI rates. Comparison of 3-month baseline period from April 1 to June 30 and follow-up period from August 1 to October 30, 2011. Baseline BSI rates were similar (0.85 vs 0.86/1,000 CVC-days), but follow-up rates differed at 0.81/1,000 CVC-days in intervention facilities versus 1.04/1,000 CVC-days in controls (P = 0.02). Intravenous antibiotic starts during the follow-up period also were lower, at 2.53/1,000 CVC-days versus 3.15/1,000 CVC-days in controls (P < 0.001). Cluster-adjusted Poisson regression confirmed 21%-22% reductions in both (P < 0.001). Extended follow-up for 3 successive quarters demonstrated a sustained reduction of bacteremia rates for patients in intervention facilities, at 0.50/1,000 CVC-days (41% reduction; P < 0.001). Hospitalizations due to sepsis during 1-year extended follow-up were 0.19/1,000 CVC-days (0.069/CVC-year) versus 0.26/1,000 CVC-days (0.095/CVC-year) in controls (∼27% difference; P < 0.05). Inability to capture results from blood cultures sent to external laboratories, underestimation of sepsis-specific hospitalizations, and potential crossover adoption of the intervention protocol in control facilities. Adoption of the new catheter care procedure (consistent with Centers for Disease Control and Prevention recommendations) resulted in a 20% lower rate of BSIs and intravenous antibiotic starts, which were sustained over time and associated with a lower rate of hospitalizations due to sepsis.

Timing of Arteriovenous Fistula Creation in Patients With CKD: A Decision Analysis

Article

Aug 2013
AM J KIDNEY DIS

The optimal time for arteriovenous fistula (AVF) referral is uncertain. Improving the timeliness of referral may reduce central venous catheter (CVC) use. Monte Carlo simulation model. Patients with chronic kidney disease (CKD) followed up in a multidisciplinary clinic, overall and stratified by age. Decision analysis, patient, patient's lifetime. AVF referral, using 1 of 2 strategies: refer when hemodialysis is anticipated to begin within a certain time frame or refer when estimated glomerular filtration rate (eGFR) drops below a certain threshold. A range of values for each strategy are compared to each other with respect to incident vascular access type (AVF or CVC), percentage of patients with an unnecessary AVF creation, and life expectancy after dialysis therapy initiation. A 15-month referral time frame gave 34% with incident CVCs, 14% with unnecessary AVFs, and a life expectancy of 1,751 days. Time frames of 12-18 months performed similarly. Referral at eGFR of 20mL/min/1.73m(2) gave 38% with incident CVCs, 20% with unnecessary AVFs, and life expectancy of 1,742 days. Using an eGFR threshold of 15mL/min/1.73m(2), 10% had an unnecessary AVF. Policy performance was affected by CKD progression rate and age. For fast progressors (ΔeGFR = -7mL/min/1.73m(2) per year), referral at eGFR of 25mL/min/1.73m(2) achieved a similar incident CVC percentage (∼40%) as referral at 15mL/min/1.73m(2) in slower progressors (ΔeGFR = -2.78mL/min/1.73m(2) per year). For patients aged 70-80 and 80-90 years, time frames of 15-18 months yielded 16%-22% with unnecessary AVFs (vs 9%-11% in 50- to 60-year-olds); an eGFR threshold strategy of 20mL/min/1.73m(2) yielded 24% unnecessary AVFs in 80- to 90-year-olds versus 16% in 50- to 60-year-olds. Our model does not consider patients with nonlinear CKD progression or acute kidney injury. We did not include arteriovenous grafts or consider cost or quality of life. In general, AVF referral within about 12 months of the estimated time to dialysis performed best among time frame strategies, and referral at eGFR < 15-20mL/min/1.73 m(2) performed best among threshold strategies. The timing of referral should also be guided by the individual rate of CKD progression. Elderly patients with CKD could be referred later to reduce the risk of creating an AVF that is never used.

Systemic Barriers to Optimal Hemodialysis Access

Article

Nov 2012

Arteriovenous fistulas (AVFs) are considered the gold standard for hemodialysis vascular access based on their superior patency, low complication rates, improved adequacy, lower costs to the health care system, and decreased risk of patient mortality. The goals of the Fistula First Breakthrough Initiative are to achieve a prevalent AVF use rate of at least 66% nationally, to decrease central venous catheter use, and to reduce overall vascular access complication rates among patients on hemodialysis. Achieving optimal vascular access is a complex process and, unlike other dialysis outcomes, requires patient involvement as well as collaboration among nephrologists, surgeons, interventionalists, dialysis facilities, primary care physicians, and hospital systems. In 2009, the Fistula First Breakthrough Initiative assembled a team from varied backgrounds and perspectives to discover the systemic root causes as to why the AVF use rate in the United States is significantly lower than that in other industrialized countries. Ultimately, the 139 latent root causes identified by the root cause analysis team fall into the categories of patient, physician, and system. This article summarizes the current controversies in regard to improving AVF placement and reducing central venous catheter use, related to each of these three categories.

Back to the Future: How Biology and Technology Could Change the Role of PTFE Grafts in Vascular Access Management

Article

Aug 2012
SEMIN DIALYSIS

Although the arteriovenous fistula (AVF) is the preferred mode of dialysis vascular access, AVF maturation failure remains a huge clinical problem, often resulting in a prolonged duration of use of tunneled dialysis catheters. In contrast, polytetrafluoroethylene (PTFE) grafts do not suffer from early failure, but have significant problems with later stenosis and thrombosis. This review will initially summarize the pathology and pathogenesis of PTFE graft dysfunction and will then use this as a basis for describing some novel therapies, which may have the potential to reduce PTFE graft dysfunction. Finally, we will emphasize that the introduction of such therapies could be an important first step toward individualizing overall vascular access care.

Learning Why Patients with Central Venous Catheters Resist Permanent Access Placement

Article

Jun 2012
Nephrol Nurs J

Central venous catheters (CVCs) are a well-known risk to patients on hemodialysis due to their higher morbidity and mortality compared to fistulas or grafts. One factor in the prevalence of CVCs is patients eligible for permanent access who refuse referral and permanent access placement. Objectives of this study were to identify reasons patients resist permanent access placement and develop potential strategies for intervention. A survey was distributed to Fresenius Medical Care North America (FMCNA) outpatient dialysis facilities (approximately 1600 facilities) requesting voluntary participation in documenting reasons given by patients for resisting permanent access placement. From the patient survey results, responses were collected and ranked from most frequent response to least frequent response. A collaborative workgroup of nephrology nurses and social workers reviewed the survey results. The patient survey provided 1573 responses. The three most frequently provided reasons were 1) a previous negative surgical experience, 2) having a permanent access placed in the past that did not work, and 3) cannulation fear and/or pain concerns. The workgroup identified best practices from clinics with low CVC rates and reviewed professional literature as a guide for development of potential strategies for intervention by the nephrology nurses and interdisciplinary team. Using a patient survey as a means to learn reasons why patients resist permanent access placement can be of value to the healthcare team in the development of potential strategies for interventions to reduce CVC utilization and thereby improve patient outcomes.

Intensity of Care and better Outcomes among Hemodialysis Patients: A Role for the Medical Director

Article

May 2012
SEMIN DIALYSIS

The Medical Director is responsible for all levels of quality patient care in the facility as mandated by the 2008 revision of the Medicare Conditions for Coverage of dialysis facilities. He/she is the leader and primary individual tasked with ensuring that facility processes are in place to meet or exceed key quality goals or adopt new ones and prioritize them appropriately-all to drive improved facility performance, particularly the ultimate outcomes of morbidity and mortality rates. Management of vascular access, dialysis dose, mineral metabolism, acid-base balance, sodium and fluid management, anemia, among other aspects of care, have representative intermediate clinical outcomes that are often called "surrogate" or "process" measures-because they may reflect the quality of care delivery while impacting "primary" outcomes such as death and hospitalization. The proportion of dialysis patients within a dialysis facility meeting a selected group among these goals has become the standard "care process" metric since the 1990s. Evidence supports its use, in that graded improvements in the facility patients' primary outcomes have been documented as more patients in a facility achieved a greater number of these "process" goals. A caveat: these process measures do not represent overall quality by themselves because nonclinical processes also influence primary outcomes. Nevertheless, process improvement in meeting facility goals should be led by the Medical Director, particularly those with the strongest links to primary outcomes such as reduction of hemodialysis catheter exposure, forming the cornerstone of quality improvement efforts. Specific recommendations on how to effectively lead a care team to achieve these goals are discussed.

Dialysis at a Crossroads-Part II: A Call for Action

Article

Apr 2012
CLIN J AM SOC NEPHRO

A previous commentary pointed out that the renal community has led American healthcare in the development and continuous improvement of quality outcomes. However, survival, hospitalization, and quality of life for US dialysis patients is still not optimal. This follow-up commentary examines the obstacles, gaps, and metrics that characterize this unfortunate state of affairs. It posits that current paradigms are essential contributors to quality outcomes but are no longer sufficient to improve quality. New strategies are needed that arise from a preponderance of evidence, in addition to beyond a reasonable doubt standard. This work offers an action plan that consists of new pathways of care that will lead to improved survival, fewer hospitalizations and rehospitalizations, and better quality of life for patients undergoing dialysis therapy. Nephrologists in collaboration with large and small dialysis organizations and other stakeholders, including the Centers for Medicare and Medicaid Services, can implement these proposed new pathways of care and closely monitor their effectiveness. We suggest that our patients deserve nothing less and must receive even more.

The Medical Director's Role in Improving Outcomes: A Nursing Perspective

Article

Apr 2012
SEMIN DIALYSIS

An economic assessment model for in-center, conventional home, and more frequent home hemodialysis

Article

Full-text available

Feb 2012
KIDNEY INT

More intensive and/or frequent hemodialysis may provide clinical benefits to patients with end-stage renal disease; however, these dialysis treatments are more convenient to the patients if provided in their homes. Here we created a standardized model, based on a systematic review of available costing literature, to determine the economic viability of providing hemodialysis in the home that arrays costs and common approaches for assessing direct medical and nonmedical costs. Our model was based on data from Australia, Canada, and the United Kingdom. The first year start-up costs for all hemodialysis modalities were higher than in subsequent years with modeled costs for conventional home hemodialysis lower than in-center hemodialysis in subsequent years. Modeled costs for frequent home hemodialysis was higher than both in-center and conventional home hemodialysis in the United Kingdom, but lower than in-center hemodialysis and higher than conventional home hemodialysis in Australia and Canada in subsequent years. The higher costs of frequent compared to conventional home hemodialysis were because of higher consumable usage due to dialysis frequency. Thus, our findings reinforce the conclusions of previous studies showing that home-based conventional and more frequent hemodialysis may provide clinical benefit at reasonable costs.

Effect of Dipyridamole plus Aspirin on Hemodialysis Graft Patency

Article

Full-text available

Jun 2009
NEW ENGL J MED

Arteriovenous graft stenosis leading to thrombosis is a major cause of complications in patients undergoing hemodialysis. Procedural interventions may restore patency but are costly. Although there is no proven pharmacologic therapy, dipyridamole may be promising because of its known vascular antiproliferative activity. We conducted a randomized, double-blind, placebo-controlled trial of extended-release dipyridamole, at a dose of 200 mg, and aspirin, at a dose of 25 mg, given twice daily after the placement of a new arteriovenous graft until the primary outcome, loss of primary unassisted patency (i.e., patency without thrombosis or requirement for intervention), was reached. Secondary outcomes were cumulative graft failure and death. Primary and secondary outcomes were analyzed with the use of a Cox proportional-hazards regression with adjustment for prespecified covariates. At 13 centers in the United States, 649 patients were randomly assigned to receive dipyridamole plus aspirin (321 patients) or placebo (328 patients) over a period of 4.5 years, with 6 additional months of follow-up. The incidence of primary unassisted patency at 1 year was 23% (95% confidence interval [CI], 18 to 28) in the placebo group and 28% (95% CI, 23 to 34) in the dipyridamole-aspirin group, an absolute difference of 5 percentage points. Treatment with dipyridamole plus aspirin significantly prolonged the duration of primary unassisted patency (hazard ratio, 0.82; 95% CI, 0.68 to 0.98; P=0.03) and inhibited stenosis. The incidences of cumulative graft failure, death, the composite of graft failure or death, and serious adverse events (including bleeding) did not differ significantly between study groups. Treatment with dipyridamole plus aspirin had a significant but modest effect in reducing the risk of stenosis and improving the duration of primary unassisted patency of newly created grafts. (ClinicalTrials.gov number, NCT00067119.)

Ethical and Legal Obligation to Avoid Long-Term Tunneled Catheter Access

Article

Full-text available

Feb 2009
CLIN J AM SOC NEPHRO

Despite recent national initiatives promoting the arteriovenous fistula as the initial, primary, and sole vascular access to be used by hemodialysis patients and recommending a decrease in the prevalence of tunneled cuffed catheters to less than 10%, the prevalence of tunneled cuffed catheters as hemodialysis access is increasing. This study describes the risks of tunneled cuffed catheters, explores the reasons why they remain prevalent, and presents the stance that nephrologists have an obligation to offer tunneled cuffed catheters only for temporary use and not as an acceptable alternative for long-term vascular access to patients for whom a properly functioning arteriovenous fistula or graft is possible. Recommendations for tunneled cuffed catheter use were based on dialysis clinical practice guidelines and the medical evidence regarding outcomes of use of arteriovenous fistulas and tunneled cuffed catheters. The authors found that compared with dialysis with arteriovenous fistulas, long-term dialysis with tunneled cuffed catheters is associated with (1) two to threefold increased risk of death, (2) a five to 10-fold increased risk of serious infection, (3) increased hospitalization, (4) a decreased likelihood of adequate dialysis, and (5) an increased number of vascular access procedures. To adequately inform patients about access options, nephrologists are ethically obligated to systematically explain to patients the harms of tunneled cuffed catheters. If catheters must be used to initiate dialysis, nephrologists should present catheters only as "temporary" measures and "unsafe for long-term use."

Longitudinal analysis of performance of estimated glomerular filtration rate as renal function declines in chronic kidney disease

Article

Full-text available

Sep 2008
NEPHROL DIAL TRANSPL

Numerous studies have assessed the accuracy of equations estimating glomerular filtration rate (eGFR) from serum creatinine in individuals with chronic kidney disease (CKD) in cross-sectional studies. Limited literature exists, however, on the consistency of performance of these equations in longitudinal studies as renal function declines. Radionucleotide-measured GFR from 155 predialysis patients with stage 3-5 CKD was compared with eGFR derived from four equations [6-variable Modification of Diet in Renal Disease (6-MDRD), 4-variable MDRD (4-MDRD), Cockcroft-Gault (CG) and Cockcroft-Gault equations corrected for body surface area (CGC)] at baseline, 12 and 24 months. Bias (difference between eGFR and measured GFR) was used as a measure of performance. Restricted Maximum Likelihood (REML) models were used to identify variables potentially affecting the performance of estimating equations across time. Mean measured GFR (+/-SD) at baseline, 12 and 24 months was 25.9 +/- 10.7, 23.1 +/- 10.6 and 20.3 +/- 10.1 mL/min/1.73 m(2), respectively. There was a statistically significant negative association between bias and GFR for all four estimates (range: -0.76 to -0.71, P < 0.001 for all), indicating worsening underestimation and overestimation at higher and lower GFR, respectively. This negative association significantly reduced over the 24 months (P < 0.001); however, this was largely due to persistent underestimation of eGFR from individuals with GFR >50 mL/min/1.73 m(2). For those with a baseline GFR <50 mL/min/1.73 m(2), the change in bias for any of the four equations over 24 months was <or=1.1 mL/min/1.73 m(2), suggesting relatively preserved performance with time. The MDRD equations showed a sustained advantage in estimating renal function that was more evident as GFR declined. GFR estimates are inexpensive and show an acceptable longitudinal performance for monitoring CKD patients with GFR <50 mL/min/1.73 m(2). Inaccuracies appear more substantial above this level of GFR, and care with interpretation is required.

Resolved: Fistulas Are Preferred to Grafts as Initial Vascular Access for Dialysis

Article

Full-text available

Oct 2008
J AM SOC NEPHROL

There is growing concern that the Fistula First Initiative, KDOQI guidelines, and subsequent pressure from the Centers for Medicare and Medicaid Services lack reasonableness regarding likely success for fistula maturation in a heterogeneous, new-onset dialysis population. Here the various positions are examined from multiple perspectives.

Vascular access use in Europe and the United States: Results from the DOPPS

Article

Full-text available

Jan 2002

A direct broad-based comparison of vascular access use and survival in Europe (EUR) and the United States (US) has not been performed previously. Case series reports suggest that vascular access practices differ substantially in the US and EUR. We report on a representative study (DOPPS) which has used the same data collection protocol for> 6400 hemodialysis (HD) patients to compare vascular access use at 145 US dialysis units and 101 units in five EUR countries (France, Germany, Italy, Spain, and the United Kingdom). Logistic analysis evaluated factors associated with native arteriovenous fistula (AVF) versus graft use or permanent access versus catheter use for prevalent and incident HD patients. Times to failure for AVF and graft were analyzed using Cox proportional hazards regression. AVF was used by 80% of EUR and 24% of US prevalent patients, and was significantly associated with younger age, male gender, lower body mass index, non-diabetic status, lack of peripheral vascular disease, and no angina. After adjusting for these factors, AVF versus graft use was still much higher in EUR than US (AOR=21, P < 0.0001). AVF use within facilities varied from 0 to 87% (median 21%) in the US, and 39 to 100% (median 83%) in EUR. For patients who were new to HD, access use was: 66% AVF in EUR versus 15% in US (AOR=39, P < 0.0001), 31% catheters in EUR vs. 60% in US, and 2% grafts in EUR vs. 24% in US. In addition, 25% of EUR and 46% of US incident patients did not have a permanent access placed prior to starting HD. In EUR, 84% of new HD patients had seen a nephrologist for> 30 days prior to ESRD compared with 74% in the US (P < 0.0001); pre-ESRD care was associated with increased odds of AVF versus graft use (AOR=1.9, P=0.01). New HD patients had a 1.8-fold greater odds (P=0.002) of starting HD with a permanent access if a facility's typical time from referral to access placement was < or =2 weeks. AVF use when compared to grafts was substantially lower (AOR=0.61, P=0.04) when surgery trainees assisted or performed access placements. When used as a patient's first access, AVF survival was superior to grafts regarding time to first failure (RR=0.53, P=0.0002), and AVF survival was longer in EUR compared with the US (RR=0.49, P=0.0005). AVF and grafts each displayed better survival if used when initiating HD compared with being used after patients began dialysis with a catheter. Large differences in vascular access use exist between EUR and the US, even after adjustment for patient characteristics. The results strongly suggest that a facility's preferences and approaches to vascular access practice are major determinants of vascular access use.

Hemodialysis Vascular Access Dysfunction: A Cellular and Molecular Viewpoint

Article

Full-text available

May 2006

Hemodialysis vascular access dysfunction is a major cause of morbidity and hospitalization in the hemodialysis population. The major cause of hemodialysis vascular access dysfunction is venous stenosis as a result of neointimal hyperplasia. Despite the magnitude of the clinical problem, however, there has been a paucity of novel therapeutic interventions in this field. This is in marked contrast to a recent plethora of targeted interventions for the treatment of arterial neointimal hyperplasia after coronary angioplasty. The reasons for this are two-fold. First there has been a relative lack of cellular and molecular research that focuses on venous neointimal hyperplasia in the specific setting of hemodialysis vascular access. Second, there have been inadequate efforts by the nephrology community to translate the recent advances in molecular and interventional cardiology into therapies for hemodialysis vascular access. This review therefore (1) briefly examines the different forms of hemodialysis vascular access that are available, (2) describes the pathology and pathogenesis of hemodialysis vascular access dysfunction in both polytetrafluoroethylene grafts and native arteriovenous fistulae, (3) reviews recent concepts about the pathogenesis of vascular stenosis that could potentially be applied in the setting of hemodialysis vascular access dysfunction, (4) summarizes novel experimental and clinical therapies that could potentially be used in the setting of hemodialysis vascular access dysfunction, and, finally, (5) offers some broad guidelines for future innovative translational and clinical research in this area that hopefully will reduce the huge clinical morbidity and economic costs that are associated with this condition.

Catheter use is high even among hemodialysis patients with a fistula or graft

Article

Full-text available

Oct 2006

At any given time, approximately 27% of patients in the United States (US) receive hemodialysis through a permanent catheter. However, this cross-sectional estimate may significantly underestimate the lifetime exposure of patients to hemodialysis catheters, and hence, to the excess risk of the adverse clinical events associated with catheter use. To further clarify catheter use in hemodialysis patients, we identified a cohort of fistula and graft patients in the US Renal Data System using Current Procedural Terminology (CPT) codes. Patients were included if their first hemodialysis was between 1 January 1996 and 31 December 2001, and Medicare was their primary payer. We identified permanent catheter insertions in these patients using CPT codes starting 6 months before their first hemodialysis session (or fistula or graft placement, if earlier), and ending 40 months afterward. Most patients (82%) were >65 years old, 57% were male, and 72% were white. The overall rate of permanent catheter insertions was 44 per 100 patient years, with 57% of patients having at least one catheter insertion. The percent of patients receiving a catheter was similar before (30%) and after (27%) the first fistula or graft placement. Cross-sectional analysis may significantly underestimate the lifetime risk of exposure to hemodialysis catheters. Because catheter use is common even in fistula and graft patients, measures used to prevent adverse events associated with catheter use are important in all patients regardless of current access type.

Risk Equation Determining Unsuccessful Cannulation Events and Failure to Maturation in Arteriovenous Fistulas (REDUCE FTM I)

Article

Full-text available

Nov 2006

Fistulas are the preferred permanent hemodialysis vascular access but a significant obstacle to increasing their prevalence is the fistula's high "failure to mature" (FTM) rate. This study aimed to (1) identify preoperative clinical characteristics that are predictive of fistula FTM and (2) use these predictive factors to develop and validate a scoring system to stratify the patient's risk for FTM. From a derivation set of 422 patients who had a first fistula created, a prediction rule was created using multivariate stepwise logistic regression. The model was internally validated using split-half cross-validation and bootstrapping techniques. A simple scoring system was derived and externally validated on 445 different, prospective patients who received a new fistula at five large North American dialysis centers. The clinical predictors that were associated with FTM were aged > or =65 yr (odds ratio [OR] 2.23; 95% confidence interval [CI] 1.25 to 3.96), peripheral vascular disease (OR 2.97; 95% CI 1.34 to 6.57), coronary artery disease (OR 2.83; 95% CI 1.60 to 5.00), and white race (OR 0.43; 95% CI 0.24 to 0.75). The resulting scoring system, which was externally validated in 445 patients, had four risk categories for fistula FTM: low (24%), moderate (34%), high (50%), and very high (69%; trend P < 0.0001). A preoperative, clinical prediction rule to determine fistulas that are likely to fail maturation was created and rigorously validated. It was found to be simple and easily reproducible and applied to predictive risk categories. These categories predicted risk of FTM to be 24, 34, 50, and 69% and are dependent on age, coronary artery disease, peripheral vascular disease, and race. The clinical utility of these risk categories in increasing rates of permanent accesses requires further clinical evaluation.

When to refer patients with chronic kidney disease for vascular access surgery: Should age be a consideration?

Article

Full-text available

Apr 2007

To determine whether age should inform our approach toward permanent vascular access placement in patients with chronic kidney disease, we conducted a retrospective cohort study among 11 290 non-dialysis patients with an estimated glomerular filtration rate (eGFR) <25 ml/min/1.73 m(2) based on 2000-2001 outpatient creatinine measurements in the Department of Veterans Affairs. For each age group, we examined the percentage of patients that had and had not received a permanent access by 1 year after cohort entry, and the percentage in each of these groups that died, started dialysis, or survived without dialysis. We also modeled the number of unnecessary procedures that would have occurred in theoretical scenarios based on existing vascular access guidelines. The mean eGFR was 17.7 ml/min/1.73 m(2) at cohort entry. Twenty-five percent (n=2870) of patients initiated dialysis within a year of cohort entry. Among these, only 39% (n=1104) had undergone surgery to place a permanent access beforehand. As compared with younger patients, older patients were less likely to undergo permanent access surgery, but also less likely to start dialysis. In all theoretical scenarios examined, older patients would have been more likely than younger patients to receive unnecessary procedures. If all patients had been referred for permanent access surgery at cohort entry, the ratio of unnecessary to necessary procedures after 2 years of follow-up would have been 5:1 for patients aged 85-100 years but only 0.5:1 for those aged 18-44 years. Currently recommended approaches to permanent access placement based on a single threshold level of renal function for patients of all ages are not appropriate.

Measurement of hemodialysis vascular access flow using extracorporeal temperature gradients

Article

Full-text available

Oct 2007

A reduction in vascular access flow poses a risk for thrombosis. We present a new technique to measure vascular access flow during dialysis based on extracorporeal temperature gradients, and their changes, on reversing the extracorporeal bloodlines without having to inject an indicator. Fistula temperatures were measured by the blood temperature monitor with normal line position and after manual switching of the bloodlines using the same extracorporeal blood flow. The access flow by our temperature gradient method (TGM) was compared to access flow derived by saline dilution with measurements in the same patients repeated in subsequent weeks. In 70 pairs of TGM and saline dilution measurements in 35 patients, the repeatability of the TGM measurements was not significantly different from that of saline dilution. There was a highly significant correlation between the two techniques with an acceptable confidence level for limits of agreement for the difference between them. It took about 9 min to complete the TGM method and about 5 min for saline dilution. Our studies show that the novel TGM method showed excellent agreement and reproducibility with the saline dilution method without the need for indicator dilution.

Preoperative Sonographic Radial Artery Evaluation and Correlation With Subsequent Radiocephalic Fistula Outcome

Article

Feb 2004
J ULTRAS MED

Objective. Primary failure of forearm radiocephalic dialysis fistulas is common even when preoperative vascular mapping is used. Previous studies have suggested that low peak systolic velocity of the radial artery predicts subsequent fistula failure. The study goal was to evaluate whether preoperative spectral Doppler assessment of radial artery inflow can improve forearm fistula outcome prediction. Methods. Forearm fistulas were placed in 112 patients after preoperative sonographic mapping. Preoperative spectral Doppler sonography measured radial artery peak systolic velocity during tight fist clenching for 3 minutes and after fist relaxation. Vessel diameters and peak systolic velocity were assessed for predictive value based on subsequent fistula adequacy. Fistula flow rates were determined 6 to 12 weeks postoperatively in a subset of patients. Results. Failed and successful fistulas were similar in their preoperative arterial and vein diameters, resistive index, and peak systolic velocity during fist clenching and after fist relaxation. Specifically, there was no difference in fistula success with radial artery peak systolic velocity lower than 50 cm/s versus peak systolic velocity of 50 cm/s or higher. The change in peak systolic velocity after fist relaxation was highly predictive of subsequent fistula outcome among female patients in ad hoc analysis. Fistula adequacy for dialysis in women was 11% when the change in peak systolic velocity was lower than 0 cm/s and 50% when the change was 0 cm/sec or higher (P = .02). The postoperative fistula flow rates were lower when the preoperative change in peak systolic velocity was lower than 0 cm/s than when it was 0 cm/s or higher (316 ± 46 versus 781 ± 150 mL/min; P = .003). Conclusions. There was no difference in the preoperative peak systolic velocity or the resistive index of successful and failed fistulas. Measurement of the radial artery peak systolic velocity change after release of fist clenching was not useful in predicting outcomes in male patients but identified a subset of female patients with a very low likelihood of success. This

The timing of referral of patients with end-stage renal disease

Article

Jan 1989

Vascular access use and outcomes: an international perspective from the dialysis outcomes and practice patterns study

Article

Jul 2008

Effect of clopidogrel on early failure of arteriovenous fistulas for hemodialysis: A randomized controlled trial

Article

Jan 2008

The UK Small Aneurysm Trial Participants. Mortality results for randomised controlled trial of early elective surgery or ultrasonographic surveillance for small abdominal aortic aneurysms. The UK Small Aneurysm Trial Participants. Lancet 352, 1649-1655

Article

Nov 1998

Background Early elective surgery may prevent rupture of abdominal aortic aneurysms, but mortality is 5-6%. The risk of rupture seems to be low for aneurysms smaller than 5 cm. We investigated whether prophylactic open surgery decreased long-term mortality risks for small aneurysms. Methods We randomly assigned 1090 patients aged 60-76 years, with symptomless abdominal aortic aneurysms 4.0-5.5 cm in diameter to undergo early elective open surgery (n=563) or ultrasonographic surveillance (n=527). Patients were followed up for a mean of 4.6 years. If the diameter of aneurysms in the surveillance group exceeded 5 5 cm, surgical repair was recommended. The primary endpoint was death. Mortality analyses were done by intention to treat. Findings The two groups had similar cardiovascular risk factors at baseline. 93% of patients adhered to the assigned treatment. 309 patients died during follow-up. The overall hazard ratio for all-cause mortality in the early-surgery group compared with the surveillance group was 0.94 (95% CI 0.75-1.17, p=0.56). The 30-day operative mortality in the early-surgery group was 5.8%, which led to a survival disadvantage for these patients early in the trial. Mortality did not differ significantly between groups at 2 years, 4 years, or 6 years. Age, sex, or initial aneurysm size did not modify the overall hazard ratio. Interpretation Ultrasonographic surveillance for small abdominal aortic aneurysms is safe, and early surgery does not provide a long-term survival advantage. Our results do not support a policy of open surgical repair for abdominal aortic aneurysms of 4 0-5.5 cm in diameter.

Chronic Kidney Disease and the Risks of Death, Cardiovascular Events, and Hospitalization

Article

Jan 2005
J VASC SURG

Risk of Hemodialysis Graft Thrombosis: Analysis of Monthly Flow Surveillance

Article

Jun 2009
J VASC SURG

Effect of Dipyridamole Plus Aspirin on Hemodialysis Graft Patency

Article

Sep 2009
J VASC SURG

Antiplatelet Therapy and Vascular-Access Patency

Article

Jun 2009
NEW ENGL J MED

Charmaine E Lok

Current predictions estimate that by the year 2020, more than 750,000 people in the United States alone will have end-stage renal disease and over 500,000 will require hemodialysis.1 The success of hemodialysis depends on a well-functioning vascular access, which may be considered the patient's lifeline. However, creating and maintaining a vascular access are challenging and costly. In the first year of hemodialysis, care of the vascular access represents the leading cause of hospitalizations; overall costs are over $1 billion annually.2,3 The Dialysis Access Consortium (DAC) Study Group has taken the lead in advancing clinical knowledge of dialysis access dysfunction . . .

Vascular Access: The Past, Present and Future

Article

Feb 2009
BLOOD PURIFICAT

Jeffrey Sands

Over the past 40 years, improvements in vascular access management have enhanced patient outcomes and decreased an epidemic of access failure. Arteriovenous fistulae are again the access of choice and new percutaneous therapies and outpatient access centers have revolutionized the therapeutic approach to access failure. Evidence-based guidelines, supported by national and international outcome data have helped rationalize vascular access care. Current challenges and, in particular, the increased use of catheters with resultant increases in patient morbidity and mortality must be rapidly addressed to protect patients and decrease the unacceptably high rates of catheter-related infection. Future technologies will continue to improve vascular access management. Our ability to utilize these new approaches to benefit patients will depend on appropriate application, continued development of standardized delivery systems utilizing outcome measures and payment systems that support and incent outcome improvement.

Acute Kidney Injury Increases Risk of ESRD among Elderly

Article

Nov 2008
J AM SOC NEPHROL

Risk for ESRD among elderly patients with acute kidney injury (AKI) has not been studied in a large, representative sample. This study aimed to determine incidence rates and hazard ratios for developing ESRD in elderly individuals, with and without chronic kidney disease (CKD), who had AKI. In the 2000 5% random sample of Medicare beneficiaries, clinical conditions were identified using Medicare claims; ESRD treatment information was obtained from ESRD registration during 2 yr of follow-up. Our cohort of 233,803 patients were hospitalized in 2000, were aged > or = 67 yr on discharge, did not have previous ESRD or AKI, and were Medicare-entitled for > or = 2 yr before discharge. In this cohort, 3.1% survived to discharge with a diagnosis of AKI, and 5.3 per 1000 developed ESRD. Among patients who received treatment for ESRD, 25.2% had a previous history of AKI. After adjustment for age, gender, race, diabetes, and hypertension, the hazard ratio for developing ESRD was 41.2 (95% confidence interval [CI] 34.6 to 49.1) for patients with AKI and CKD relative to those without kidney disease, 13.0 (95% CI 10.6 to 16.0) for patients with AKI and without previous CKD, and 8.4 (95% CI 7.4 to 9.6) for patients with CKD and without AKI. In summary, elderly individuals with AKI, particularly those with previously diagnosed CKD, are at significantly increased risk for ESRD, suggesting that episodes of AKI may accelerate progression of renal disease.

More Than Reducing Early Fistula Thrombosis Is Required: Lessons From the Dialysis Access Consortium Clopidogrel Fistula Study

Article

Dec 2008
AM J KIDNEY DIS

Risk of Hemodialysis Graft Thrombosis: Analysis of Monthly Flow Surveillance

Article

Oct 2008
AM J KIDNEY DIS

During clinical application of flow surveillance of hemodialysis grafts, the risk of thrombosis is assessed month after month, rather than after one or several measurements, as has been done in published studies. Adequate assessment of risk should consider the many measurements obtained over time. Prospective cohort diagnostic test study. 176 patients with hemodialysis grafts from 2 university-affiliated dialysis units during a 6-year period. Monthly measurement of graft blood flow or change in flow. Graft thrombosis. We used logistic regression analysis to compute the risk of thrombosis and used receiver operating characteristic (ROC) curves to assess the accuracy in predicting thrombosis within 1 month. Newer grafts were most likely to thrombose, whereas older grafts were unlikely to thrombose even at low flows or large decreases in flow. Areas under the ROC curves were 0.698 for flow and 0.713 for change in flow measured over 2 months. Flow predicted thrombosis with a sensitivity of 53% at a specificity of 79%, and change in flow had a sensitivity of 58% at a specificity of 75%. More than half the thromboses lacked a change in flow measurement, usually because thrombosis occurred before a change could be measured. Thus, the effective predictive accuracy of change in flow was much less than the ROC curves indicated because the curves do not consider missing measurements. Performance characteristics of index tests may vary across patient populations. Flow and change in flow are inaccurate predictors of thrombosis. Many thromboses are not predicted, and intervention based on surveillance likely yields many unnecessary procedures. Thus, this study does not support routine application of surveillance to prevent thrombosis.

Variability and Risk Factors for Kidney Disease Progression and Death Following Attainment of Stage 4 CKD in a Referred Cohort

Article

Oct 2008
AM J KIDNEY DIS

The outcomes of patients referred to nephrologists are not well described in large cohorts. The objectives of this analysis are to describe the predictors of rapid progression of kidney disease and death in patients followed up by nephrologists. Retrospective study. A cohort derived from all patients registered in the provincial database was formed that included all patients with index estimated glomerular filtration rate (eGFR) less than 30 mL/min/1.73 m(2), at least 3 subsequent eGFR values, and 4 months of follow-up between January 2000 and January 2004. Variables used to predict outcomes included baseline eGFR, duration of follow-up before eGFR less than 30 mL/min/1.73 m(2), age, sex, ethnicity, presence of diabetes, blood pressure, level of proteinuria, hemoglobin level, phosphate level, calcium level, parathyroid hormone level, and use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, erythropoiesis-stimulating agents, and vitamin D. Key outcomes of interest were death, dialysis therapy start, or loss of GFR greater than 5 mL/min/1.73 m(2)/y. 4,231 patients met inclusion criteria. Mean age was 67 years. Median follow-up was 31 months. During the first 2 years of follow-up, 24% started dialysis therapy, 1% received a transplant, 7% died, and 1% was lost to follow-up. Statistically significant variables associated with more rapid kidney disease progression differ from those that predict death. Younger age, male sex, higher eGFR, higher systolic and diastolic blood pressure, lower hemoglobin level, higher phosphorus and parathyroid hormone levels, and greater proteinuria are associated with more rapid kidney disease progression, and use of angiotensin-converting enzymes/angiotensin receptor blockers are protective. Older age, lower diastolic blood pressure, lower hemoglobin level, and higher phosphorous and parathyroid hormone levels are associated with death, whereas vitamin D use is protective. Results cannot be generalized to unreferred patients with eGFR less than 30 mL/min/1.73 m(2). The clinical course of patients with chronic kidney disease stage 4 is variable. Targeted therapy aimed at modifiable risk factors needs to be evaluated to determine benefits of this approach.

Neuroblastoma in Europe: differences in the pattern of disease in the UK. SENSE. Study group for the Evaluation of Neuroblastoma Screening in Europe

Article

Sep 1998

Neuroblastoma is a major contributor to childhood cancer mortality, but its prognosis varies with age and stage of disease, and some tumours regress spontaneously. Urinary screening programmes or clinical examination may detect the disease before symptoms appear, but the benefit of early diagnosis is uncertain. We examined the incidence, pattern, and presentation of neuroblastoma in four European countries. Population-based incidence rates were derived for France, Austria, Germany, and the UK. Age, sex, and stage distribution were analysed by Mantel-Haenszel techniques and Poisson regression. The proportion of incidental diagnoses (cases without symptoms found at routine health checks or during investigation of other disorders) and mortality rates were also compared. Between 1987 and 1991, 1672 cases of neuroblastoma were diagnosed in children under 15 years old (France, 624; Austria, 69; Germany, 493; UK, 486). Age-standardised annual incidence was significantly lower in the UK (10.1/million) than in France (12.5) and Germany (11.4). In the UK a deficit of low-stage disease in infants was accompanied by an excess of stage IV in older children. The UK had significantly fewer incidental diagnoses (8%) than Austria (27%) and Germany (34%). UK mortality rates were significantly higher than German or French rates. In the UK, neuroblastoma diagnosis is delayed, possibly because of a less rigorous system of health checks for children. Although some overdiagnosis occurs in mainland Europe, our data suggest that in the UK some low-stage cases, undetected in infancy, may later present as advanced disease. This finding has implications for screening programmes and organisation of routine surveillance of infant health in the UK.

Hemodialysis access failure: A call to action

Article

Nov 1998

Recent evidence suggests that the cost as well as the morbidity associated with the maintenance of hemodialysis access is increasing rapidly; currently, the cost exceeds 1 billion dollars and access related hospitalization accounts for 25% of all hospital admissions in the U.S.A. This increase in cost and morbidity has been associated with several epidemiological trends that may contribute to access failure. These include late patient referral to nephrologists and surgeons, late planning of vascular access as well as a shift from A-V fistulaes to PTFE grafts and temporary catheters, which have a higher failure rate. The reasons for this shift in the types of access is multifactorial and is not explained by changes in the co-morbidities of patients presenting to dialysis. Surgical preference and training also appear to play an important role in the large regional variation and patency rate of these PTFE grafts. We propose a program for early placement of A-V fistulae, a continuous quality improvement, multidisciplinary program to monitor access outcome, the development of new biomaterials, and a research plan to investigate pharmacological intervention to reduce development of stenosis and clinical interventions to treat those that do develop, prior to thrombosis.

US Vascular Mapping before Hemodialysis Access Placement1

Article

Nov 2000

To prospectively assess the effect of preoperative ultrasonographic (US) mapping on surgical selection, placement of arteriovenous fistulas (AVFs) and grafts, and negative surgical exploration rates. US assessment of the upper extremity arterial and venous anatomy was performed in 70 patients with chronic renal failure before surgical evaluation. The surgeon documented the planned access procedure, which was based on physical examination results, and then reviewed the US preoperative mapping report. The surgical procedure and outcome were recorded. Fifty-two of the 70 patients who underwent mapping had vascular access placement. Preoperative US mapping resulted in a change in the planned surgical procedure in 16 (31%) of the 52 patients. An AVF rather than the planned graft was placed in eight (15%) patients. The AVF placement rate increased from 32% (126 of 395 patients) to 58% (30 of 52 patients). Unsuccessful surgical explorations decreased from 11% (28 of 256) to 0%. Preoperative US mapping before hemodialysis access placement can result in a change in surgical management, with an increased number of AVFs placed and an improved likelihood of selecting the most functional vessels preoperatively. Further study is needed to determine longer term outcomes.

Factors associated with the prevalence of arteriovenous fistulas in hemodialysis patients in the HEMO study. Hemodialysis (HEMO) Study Group

Article

Dec 2000

Arteriovenous (AV) fistulas are the vascular access of choice for hemodialysis patients, but only about 20% of hemodialysis patients in the United States dialyze with fistulas. There is little information known about the factors associated with this low prevalence of fistulas. Multiple logistic regression analysis was used to evaluate the independent contribution of factors associated with AV fistula use among patients enrolled in the HEMO Study. The analysis was conducted in 1824 patients with fistulas or grafts at 45 dialysis units (15 clinical centers). Thirty-four percent of the patients had fistulas. The prevalence of fistulas varied markedly from 4 to 77% among the individual dialysis units (P < 0.001). Multiple regression analysis revealed five demographic and clinical factors that were each independently associated with a lower likelihood of having a fistula, even after adjustment for dialysis unit. Specifically, the prevalence of fistulas was lower in females than males [adjusted odds ratio (AOR) 0.37, 95% CI, 0.28 to 0.48], lower in patients with peripheral vascular disease than in those without (AOR 0.55, 95% CI, 0.38 to 0.79), lower in blacks than in non-blacks (AOR 0.64, 95% CI, 0.46 to 0.89), lower in obese patients (AOR per 5 kg/m(2) body mass index, 0.76, 95% CI, 0.65 to 0.87), and lower in older patients (AOR per 10 years, 0.85, 95% CI, 0.78 to 0.94). The differences in the prevalence of fistulas among the dialysis units remained statistically significant (P < 0.001) after adjustment for these demographic and clinical factors. Finally, there were substantial variations in the prevalence of fistulas even among dialysis units in a single metropolitan area. Future efforts to increase the prevalence of fistulas in hemodialysis patients should be directed at both hemodialysis units and patient subpopulations with a low fistula prevalence.

Haemodialysis renal replacement therapy - Do we need more research?

Article

May 2001

Timing of nephrologist referral and arteriovenous access use: The CHOICE Study

Article

Sep 2001
AM J KIDNEY DIS

Recent clinical practice guidelines recommend the creation of an arteriovenous (AV) vascular access (ie, native fistula or synthetic graft) before the start of chronic hemodialysis therapy to prevent the need for complication-prone dialysis catheters. We report on the association of referral to a nephrologist with duration of dialysis-catheter use and type of vascular access used in the first 6 months of hemodialysis therapy. The study population is a representative cohort of 356 patients with questionnaire, laboratory, and medical record data collected as part of the Choices for Healthy Outcomes in Caring for End-Stage Renal Disease Center Study. Patients who reported being seen by a nephrologist at least 1 month before starting hemodialysis therapy (75%) were more likely than those referred later to use an AV access at initiation (39% versus 10%; P < 0.001) and 6 months after starting hemodialysis therapy (74% versus 56%; P < 0.01). Patients referred within 1 month of initiating hemodialysis therapy used a dialysis catheter for a median of 202 days compared with 64, 67, and 19 days for patients referred 1 to 4, 4 to 12, and greater than 12 months before initiating hemodialysis therapy, respectively (P trend < 0.001). Patients referred at least 4 months before initiating hemodialysis therapy were more likely than patients referred later to use an AV fistula, rather than a synthetic graft, as their first AV access (45% versus 31%; P < 0.01). These associations remained after adjustment for age, sex, race, marital status, education, insurance coverage, comorbid disease status, albumin level, body mass index, and underlying renal diagnosis. These data show that late referral to a nephrologist substantially increases the likelihood of dialysis-catheter use at the initiation of hemodialysis therapy and is associated with prolonged catheter use. Regardless of the time of referral, only a minority of patients used an AV access at the initiation of treatment, and greater than 25% had not used an AV access 6 months after initiation. Thus, further efforts to improve both referral patterns and preparation for dialysis after referral are needed.

Identification of patients and risk factors in chronic kidney disease - Evaluating risk factors and therapeutic strategies

Article

Feb 2001

Adeera Levin

Three strategies can help delay chronic kidney disease (CKD) progression: early identification of patients, modification of risk factors, and implementation of the best interventions. Early identification of patients requires accurate screening tools. As serum creatinine is an unreliable marker of kidney dysfunction, clinicians should focus on the glomerular filtration rate or other markers of true kidney function. Clinicians should also be aware of other indicators of abnormal kidney function, such as anaemia, acidosis, and increases in parathyroid hormone level. Additionally, both clinicians and patients should be aware of the "non-modifiable" and "modifiable" risk factors for CKD. Non-modifiable risk factors include age, gender, race, diabetes, and genetic make-up, while modifiable risk factors include elevated blood pressure and blood glucose, proteinuria, anaemia, metabolic disturbances, and dyslipidaemia. Patients should be particularly aware of the risk factors common to both cardiac and kidney disease, such as hypertension, proteinuria, anaemia, and (possibly) dyslipidaemia and diabetes. A single centre study demonstrated that inclusion in a multidisciplinary CKD clinic programme produced the greatest increases in time to renal replacement therapy, haemoglobin levels, and epoetin treatment usage at initiation of dialysis in comparison with standard nephrology care or no care. Two years after starting dialysis, the number of deaths was lowest, and the number of patients who had received a transplant or were still on dialysis was highest, in the CKD clinic-treated group. These results confirm those of previous studies, which showed that timely referral to a multidisciplinary team for management prior to dialysis decreases the risk of adverse patient outcomes. This suggests that a multidisciplinary, collaborative, proactive approach increases the likelihood of early identification of CKD patients and risk factor modification. However, further evidence-based demonstrations of success are required, showing benefit to both patients and health care systems.

Vascular access and increase risk of death among hemodialysis patients

Article

Aug 2002

Hemodialysis with a venous catheter increases the risk of infection. The extent to which venous catheters are associated with an increased risk of death among hemodialysis patients has not been extensively studied. We conducted a retrospective cohort study of 7497 prevalent hemodialysis patients to assess the association between dialysis with a venous catheter and risk of death due to all causes and to infection. A tunneled cuffed catheter was used for access in 12% of the patients and non-cuffed, not tunneled catheter in 2%. Younger age (P = 0.0005), black race (P = 0.0022), female gender (P = 0.0004), short duration since starting dialysis (P = 0.0003) and impaired functional status (P = 0.0001) were independently associated with increased use of catheter access. The proportion of patients who died was higher among those who were dialyzed with a non-cuffed (16.8%) or cuffed (15.2%) catheter compared to those dialyzed with either a graft (9.1%) or a fistula (7.3%; P < 0.001). The proportion of deaths due to infection was higher among patients dialyzed with a catheter (3.4%) compared to those dialyzed with either a graft (1.2%) or a fistula (0.8%; P < 0.001). The adjusted odds ratio (95% CI) for all-cause and infection-related death among patients dialyzed with a catheter was 1.4 (1.1, 1.9) and 3.0 (1.4, 6.6), respectively, compared to those with an arteriovenous (AV) fistula. Venous catheters are associated with an increased risk of all-cause and infection-related mortality among hemodialysis patients.

Delayed nephrologist referral and inadequate vascular access in patients with advanced chronic kidney failure

Article

Jul 2002
J CLIN EPIDEMIOL

We sought to determine whether late referral to a nephrologist in patients with chronic renal failure influences the adequacy of vascular access for hemodialysis. We analyzed data describing all health care encounters for all Medicare and Medicaid patients with end-stage renal failure in New Jersey between January 1991 and June 1996. Patients were required to have been diagnosed with renal disease at least 1 year prior to onset of hemodialysis. In the resulting cohort of 2,398 incident hemodialysis patients, 35% had their first nephrologist consultation < or =90 days prior to initiation of dialysis. After controlling for demographic characteristics, socio-economic status and underlying renal disease, we found that patients who were referred to a nephrologist >90 days prior to onset of hemodialysis were 38% more likely to have undergone predialysis vascular access surgery than those who were referred to a nephrologist < or =90 days before dialysis [OR: 1.38; 95% CI (1.15; 1.64)]. Similarly, patients referred late were 42% more likely to require central venous access for hemodialysis compared to those seen by a nephrologist early [OR: 1.42; 95% CI (1.17; 1.71)]. Inadequate development of vascular access for renal replacement therapy in patients with late nephrologist referral unnecessarily contributes to the burden of disease experienced by this vulnerable patient population.

Increasing arteriovenous fistulas in hemodialysis patients: Problems and solutions

Article

Nov 2002

National guidelines promote increasing the prevalence of fistula use among hemodialysis patients. The prevalence of fistulas among hemodialysis patients reflects both national, regional, and local practice differences as well as patient-specific demographic and clinical factors. Increasing fistula prevalence requires increasing fistula placement, improving maturation of new fistulas, and enhancing long-term patency of mature fistulas for dialysis. Whether a patient receives a fistula depends on several factors: timing of referral for dialysis and vascular access, type of fistula placed, patient demographics, preference of the nephrologist, surgeon, and dialysis nurses, and vascular anatomy of the patient. Whether the placed fistula is useable for dialysis depends on additional factors, including adequacy of vessels, surgeon's experience, patient demographics, nursing skills, minimal acceptable dialysis blood flow, and attempts to revise immature fistulas. Whether a mature fistula achieves long-term patency depends on the ability to prevent and correct thrombosis. An optimal outcome is likely when there is (1) a multidisciplinary team approach to vascular access; (2) consensus about the goals among all interested parties (nephrologists, surgeons, radiologists, dialysis nurses, and patients); (3) early referral for placement of vascular access; (4) restriction of vascular access procedures to surgeons with demonstrable interest and experience; (5) routine, preoperative mapping of the patient's arteries and veins; (6) close, ongoing communication among the involved parties; and (7) prospective tracking of outcomes with continuous quality assessment. Implementing these measures is likely to increase the prevalence of fistulas in any given dialysis unit. However, differences among dialysis units are likely to persist because of differences in gender, race, and co-morbidity mix of the patient population.

Creation, cannulation and survival of arteriovenous fistulae: Data from the Dialysis Outcomes and Practice Patterns Study

Article

Jan 2003

An arteriovenous (A-V) fistula is the optimal vascular access for hemodialysis. The National Kidney Foundation Dialysis Outcomes Quality Initiative (DOQI) recommends that fistulae should mature for at least one month before cannulation, but this recommendation is not evidence-based. If fistulae are created prior to ESRD and cannulation is possible earlier without compromising fistula survival, the need for temporary catheters would be reduced. Prospective observational data were analyzed for a random sample (N = 3674) of incident patients at the time of initiating hemodialysis, hemofiltration or hemodiafiltration in 309 facilities in France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States, taking part in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Although the proportion of patients who had pre-dialysis care by a nephrologist differed little between countries, there were large variations in the proportion of patients who commenced hemodialysis via an A-V fistula, A-V graft or central venous catheter. The usual time interval between referral and creation of A-V fistulae also differed greatly between countries. For new hemodialysis (HD) patients initiating HD with an A-V fistula (N = 894) the following results were observed: (1). median time to first cannulation varied greatly between countries: Japan and Italy (25 and 27 days), Germany (42 days), Spain and France (80 and 86 days), UK and US (96 and 98 days). (2). No association was found between cannulation <or=28 days versus>28 days for patient characteristics of age, gender, and fifteen different classes of patient co-morbid factors. (3). Risk of A-V fistula failure was increased for incident patients who had a prior temporary access [relative risk (RR) = 1.81, P = 0.01] or who were female (RR = 1.52, P = 0.02). (4). Cannulation <or=14 days after creation was associated with a 2.1-fold increased risk of subsequent fistula failure (P = 0.006) compared to fistulae cannulated>14 days. (5) No significant difference in A-V fistula failure was seen for fistulae cannulated in 15 to 28 days compared with 43 to 84 days. Significant differences in clinical practice currently exist between countries regarding the creation of A-V fistulae prior to starting hemodialysis and the timing of initial cannulation. Cannulation within 14 days of creation is associated with reduced long-term fistula survival. Fistulae ideally should be left to mature for at least 14 days before first cannulation.

Physician Operators Forum of RMS Lifeline. Aggressive treatment of early fistula failure

Article

Nov 2003

Fistula failure has been classified as early and late. Early failure refers to those cases in which the arteriovenous (AV) fistula never develops to the point that it can be used or fails within the first 3 months of usage. It has been common practice to abandon these early failures; however, aggressive evaluation and treatment of early fistula failures has been shown to result in the salvage of a large percentage. The two most common causes of the failure seen at this time are juxta-anastomotic stenosis (JAS) and the presence of accessory veins. Both of these can be easily diagnosed by physical examination. This study reports the results of early fistula failure managed aggressively in an attempt at salvage. These studies were conducted in six freestanding outpatient interventional facilities in different regions of the United States. Interventional nephrologists are employed at all of these facilities except one that is operated by an interventional radiologist. Each patient was first evaluated angiographically to identify the anatomy of their AV fistula and detect abnormalities that might be present. Stenotic lesions were then treated with angioplasty and accessory veins thought to be significant were obliterated. All patients were then followed to determine if the fistula was usable for dialysis. One hundred patients were identified that met the definition of early failure. Venous stenosis was present in 78% of these cases. In 43% of the cases, the lesion was in the JAS location. In 15%, this was the only lesion present. In 24%, it was associated with an accessory vein, in 6% with a proximal stenosis, and in 4% with both. A proximal stenosis lesion was present in the fistula in 36%. In 6%, it was associated with an accessory vein, in 6% with a JAS, and in 4% with both. The definition of arterial anastomosis stenosis was met in 38% of the cases. This was always in association with JAS. In four cases, a stenotic lesion was present in the artery above the anastomosis. An accessory vein was present in 46% of the cases. In 12% of the cases, this was the only lesion present. In 24% of the cases, this anomaly was associated with JAS, in 6% with proximal stenosis, and in 4% with both. Angioplasty was performed to treat venous stenosis in 72% of the cases with a 98% success rate. Angioplasty of the arterial anastomosis was performed in 38 cases with a 100% success rate. Accessory vein obliteration was performed in 46% of the patients with a 100% success rate. The overall complication rate in this series was 4%, of these 3% were minor and 1% were major. It was possible to initiate dialysis using the fistula in 92% of the cases. Actuarial life-table analysis showed that 84% were functional at 3 months, 72% at 6 months, and 68% at 12 months. If correctable pathology is detected in patients with early fistula failure, the incidence of correctable lesions is relatively high and an aggressive therapeutic approach can be expected to have a high yield.

Pathogenesis and treatment of kidney disease and hypertension. A population-based study of the incidence and outcomes of diagnosed chronic kidney disease

Article

Oct 2003
AM J KIDNEY DIS

This study aims to determine the incidence rate and prognosis of detected chronic kidney disease (CKD) in a defined population. This is a retrospective cohort study of all new cases of CKD from Southampton and South-West Hampshire Health Authority (population base, 405,000) determined by a persistently increased serum creatinine (SCr) level (>or=1.7 mg/dL [>or=150 micromol/L] for 6 months) identified from chemical pathology records. Follow-up was for a mean of 5.5 years for survival, cause of death, and acceptance to renal replacement therapy (RRT). The annual incidence rate of detected CKD was 1,701 per million population (pmp; 95% confidence interval [CI], 1,613 to 1,793) and 1,071 pmp (95% CI, 1,001 to 1,147) in those younger than 80 years. There was a steep age gradient; median age was 77 years. The man-woman rate ratio was 1.6 (95% CI, 1.4 to 1.8), with a male excess in all age groups older than 40 years. Incidence increased in areas with greater socioeconomic deprivation. Median survival was 35 months. Age, SCr level, and deprivation index were all significantly associated with survival. Standardized mortality ratios were 36-fold in those aged 16 to 49 years, 12-fold in those aged 50 to 64 years, and more than 2-fold in those older than 65 years. Cardiovascular disease (CVD) was the most common cause of death (46%). Only 4% of patients were accepted to RRT. The incidence of diagnosed CKD is common, especially in the elderly, and is greater in more deprived areas. Prognosis is poor, with CVD prominent. More research is needed to assess the effectiveness and costs of increasing referral to nephrologists of patients with CKD.

Preoperative Sonographic Radial Artery Evaluation and Correlation with Subsequent Radiocephalic Fistula Outcome

Article

Mar 2004

Primary failure of forearm radiocephalic dialysis fistulas is common even when preoperative vascular mapping is used. Previous studies have suggested that low peak systolic velocity of the radial artery predicts subsequent fistula failure. The study goal was to evaluate whether preoperative spectral Doppler assessment of radial artery inflow can improve forearm fistula outcome prediction. Forearm fistulas were placed in 112 patients after preoperative sonographic mapping. Preoperative spectral Doppler sonography measured radial artery peak systolic velocity during tight fist clenching for 3 minutes and after fist relaxation. Vessel diameters and peak systolic velocity were assessed for predictive value based on subsequent fistula adequacy. Fistula flow rates were determined 6 to 12 weeks postoperatively in a subset of patients. Failed and successful fistulas were similar in their preoperative arterial and vein diameters, resistive index, and peak systolic velocity during fist clenching and after fist relaxation. Specifically, there was no difference in fistula success with radial artery peak systolic velocity lower than 50 cm/s versus peak systolic velocity of 50 cm/s or higher. The change in peak systolic velocity after fist relaxation was highly predictive of subsequent fistula outcome among female patients in ad hoc analysis. Fistula adequacy for dialysis in women was 11% when the change in peak systolic velocity was lower than 0 cm/s and 50% when the change was 0 cm/sec or higher (P = .02). The postoperative fistula flow rates were lower when the preoperative change in peak systolic velocity was lower than 0 cm/s than when it was 0 cm/s or higher (316 +/- 46 versus 781 +/- 150 mL/min; P = .003). There was no difference in the preoperative peak systolic velocity or the resistive index of successful and failed fistulas. Measurement of the radial artery peak systolic velocity change after release of fist clenching was not useful in predicting outcomes in male patients but identified a subset of female patients with a very low likelihood of success. This criterion may merit further investigation in future trials.

Unreferred Chronic Kidney Disease: A Longitudinal Study

Article

May 2004
AM J KIDNEY DIS

Chronic kidney disease (CKD) is a major health problem. A better understanding of the epidemiological characteristics of the different stages of CKD and the associated adverse outcomes is needed to establish and implement appropriate management strategies. A serum creatinine (SCr) level of 2.03 mg/dL or greater (> or =180 micromol/L) in men and 1.53 mg/dL or greater (> or =135 micromol/L) in women was used to identify patients with moderate to severe CKD in a predominantly Caucasian area of the United Kingdom. Patients who were unknown to renal services were identified and followed up to establish survival, rate of referral, and change in glomerular filtration rate (GFR). The prevalence of CKD defined by SCr cutoff values was 5,554 per million population (pmp). Median calculated GFR of the cohort was 28.5 mL/min/1.73 m2 (range, 4.1 to 42.8 mL/min/1.73 m2), and median age was 83 years (range, 18 to 103 years). A total of 84.8% of patients were unknown to renal services. During a mean follow-up of 31.3 months, 8.1% of patients were referred. Median survival of the unreferred population was 28.1 months. Cardiovascular disease, cancer, and infection were the most common causes of death. Male sex, low GFR, and nonreferral were associated with poor outcome. The majority of unreferred patients had stable renal function. The incidence of new unreferred CKD during the first year of follow-up was 2,435 pmp, such that the prevalence remained stable at 4,910 pmp. Significant anemia (hemoglobin < 11 g/dL [<110 g/L]) was seen in 27.5% of the unreferred cohort. Referral of all patients with CKD is unrealistic and inappropriate. Management strategies aimed at improving adverse outcomes need to take account of this and be developed and implemented through collaboration between primary care and secondary care.

Late Creation of Vascular Access for Hemodialysis and Increased Risk of Sepsis

Article

Aug 2004

The creation of fistulas or grafts before starting dialysis is recommended, but whether it reduces major adverse events is largely unknown. The objective of this study was to determine if early access creation was associated with a reduced risk of hospitalization from sepsis and mortality. Fistulas or grafts created at least 4 mo before starting hemodialysis were defined as Early creations (n = 1240), and accesses created between 4 mo and 1 mo before starting hemodialysis were defined as Just Prior creations (n = 997). Accesses created within 1 mo of starting dialysis or after were defined as Late creations (reference group, n = 3687). Hemodialysis catheter use was defined as insertion, removal, or manipulation of a catheter before the occurrence of sepsis. Eighty percent of accesses were fistulas. Early access creation was associated with a relative risk (RR) of sepsis of 0.57 (95% CI, 0.41 to 0.79) compared with Late access creation. Catheter use increased the risk of sepsis by 1.41 (95% CI, 1.14 to 1.81). The risk of sepsis with Early creation decreased to 0.48 (95% CI, 0.35 to 0.65) if catheter use was not adjusted. Early access creation was associated with lower mortality (RR 0.76; 95% CI 0.58 to 1.00), but this association became nonsignificant if catheter use and sepsis were adjusted. Catheter use and sepsis independently increased mortality. This study demonstrates that fistula creation at least 4 mo before starting chronic hemodialysis is associated the lowest risk of sepsis and death, primarily by reducing the use of hemodialysis catheters.

Timing of first cannulation and vascular access failure in haemodialysis: An analysis of practice patterns at dialysis facilities in the DOPPS

Article

Sep 2004

Chronic Kidney Disease and the Risks of Death, Cardiovascular Events, and Hospitalization

Article

Oct 2004
NEW ENGL J MED

End-stage renal disease substantially increases the risks of death, cardiovascular disease, and use of specialized health care, but the effects of less severe kidney dysfunction on these outcomes are less well defined. We estimated the longitudinal glomerular filtration rate (GFR) among 1,120,295 adults within a large, integrated system of health care delivery in whom serum creatinine had been measured between 1996 and 2000 and who had not undergone dialysis or kidney transplantation. We examined the multivariable association between the estimated GFR and the risks of death, cardiovascular events, and hospitalization. The median follow-up was 2.84 years, the mean age was 52 years, and 55 percent of the group were women. After adjustment, the risk of death increased as the GFR decreased below 60 ml per minute per 1.73 m2 of body-surface area: the adjusted hazard ratio for death was 1.2 with an estimated GFR of 45 to 59 ml per minute per 1.73 m2 (95 percent confidence interval, 1.1 to 1.2), 1.8 with an estimated GFR of 30 to 44 ml per minute per 1.73 m2 (95 percent confidence interval, 1.7 to 1.9), 3.2 with an estimated GFR of 15 to 29 ml per minute per 1.73 m2 (95 percent confidence interval, 3.1 to 3.4), and 5.9 with an estimated GFR of less than 15 ml per minute per 1.73 m2 (95 percent confidence interval, 5.4 to 6.5). The adjusted hazard ratio for cardiovascular events also increased inversely with the estimated GFR: 1.4 (95 percent confidence interval, 1.4 to 1.5), 2.0 (95 percent confidence interval, 1.9 to 2.1), 2.8 (95 percent confidence interval, 2.6 to 2.9), and 3.4 (95 percent confidence interval, 3.1 to 3.8), respectively. The adjusted risk of hospitalization with a reduced estimated GFR followed a similar pattern. An independent, graded association was observed between a reduced estimated GFR and the risk of death, cardiovascular events, and hospitalization in a large, community-based population. These findings highlight the clinical and public health importance of chronic renal insufficiency.

Vascular access results from the Dialysis Outcomes and Practice Patterns Study (DOPPS): Performance against Kidney Disease Outcomes Quality Initiative (K/DOQI) Clinical Practice Guidelines

Article

Dec 2004
AM J KIDNEY DIS

The Kidney Disease Outcomes Quality Initiative Guidelines for Vascular Access in hemodialysis patients recommend native arteriovenous (AV) fistulae over AV grafts or catheters for permanent vascular access. They recommend letting fistulae mature > or =1 month before cannulation. The Dialysis Outcomes and Practice Patterns Study (DOPPS) provides an unparalleled means to examine vascular access practice patterns and guidelines internationally, with particular attention to associations with mortality risk. Most patients in Europe and Japan dialyze through AV fistulae and very few use AV grafts; in the United States, more patients use grafts than fistulae. Patients who receive nephrologic care for over 30 days before starting dialysis have significantly higher chances of commencing via AV fistula. Medical directors of dialysis facilities in the United States commonly prefer grafts; in Europe and Japan, most prefer fistulae. In the United States, there is a relatively long average time between fistula creation and cannulation but significantly worse fistula survival than that seen in Europe. Tunneled catheters pose a higher mortality risk than permanent accesses and are associated with increased risk of failure of a subsequent fistula. The percentage of prevalent patients in the DOPPS countries using catheters has increased in recent years. DOPPS data suggest that performance in some countries falls short of practices achieved in other countries. AV fistula use is low in the United States but has been improving. The trend of increasing use of catheters in most countries is discouraging. The DOPPS will continue to monitor practice trends and explore whether greater application of guidelines will lead to fewer access complications and improved longevity for hemodialysis patients.

The progression of chronic kidney disease: A 10-year population-based study of the effects of gender and age

Article

Feb 2006

The increase in demand for renal replacement therapy makes it important to investigate the prognosis of the earlier stages of chronic kidney disease (CKD). We examined the change in glomerular filtration rate (GFR), and patient and renal survival in CKD stage 3 in the municipality of Tromsø, a well-defined European community with a population of 58,000. All patients with estimated GFR between 30 and 59 ml/min/1.73 m(2) for more than 3 months during a 10-year study period were identified from a complete database of all 248 560 measurements of serum creatinine made in the community in the study period. Change in GFR was estimated for each patient using a multilevel model. A complete follow-up with respect to patient and renal survival was obtained from hospital databases. A total of 3047 patients was included. The median number of measurements of creatinine for each patient was 9, and the median observation time was 44 months. Mean estimated change in GFR was--1.03 ml/min/1.73 m(2)/year. Seventy-three percent of the patients experienced a decline in GFR. The 10-year cumulative incidence of renal failure was 0.04 (95% CI 0.03-0.06) and mortality 0.51 (95% CI 0.48-0.55). Female gender was associated with slower decline in GFR and better patient and renal survival. In this population-based study, the decline in GFR in CKD was slower than in previously studied selected patient groups. A high mortality pre-empted the development of renal failure in many patients. The prognosis of CKD depended strongly on gender.

Why don't fistulas mature?

Article

Nov 2006

Bradley S Dixon

Fistula maturation requires a compliant and responsive vasculature capable of dilating in response to the increased velocity of blood flowing into the newly created low-resistance circuit. Successful maturation to a high volume flow circuit capable of sustaining hemodialysis typically occurs within the first few weeks after creation. Failure to achieve maturation within 4-8 weeks should prompt a search for reversible etiologies; however, an accepted definition of maturation, particularly for patients not yet on dialysis remains elusive. The most commonly identified etiology is neointimal hyperplasia typically occurring in the juxta-anastomotic vein. However, failed maturation has also been reported secondary to impaired arterial and venous dilation and accessory veins. The exact frequency of each of these etiologies is unclear. Understanding the etiologies of impaired fistula maturation will focus future studies of targeted interventions to improve the rate of fistula maturation and increase the number of dialysis patients with a functioning autogenous fistula.

Impact of surgeon and surgical center characteristics on choice of permanent vascular access

Article

Aug 2003

The impact of the surgeon and surgical center characteristics on choice of autogenous arteriovenous (AV) fistula versus artificial AV graft as permanent vascular access for hemodialysis has not been studied. We used national data from the Department of Veterans Affairs Veterans Health Administration to measure the association of surgeon and surgical center characteristics with choice of initial permanent vascular access among patients undergoing their first vascular access placement procedure between October 1, 2000 and September 30, 2001 (fiscal year 2001). Data were analyzed using a hierarchical logistic regression model clustered for surgical center and surgeon. The study population included 1114 patients, 74 Veterans Administration Medical Centers, and 182 surgeons. Seventy-two percent of patients received an AV fistula as their initial form of permanent vascular access. After adjusting for differences in patient, center, and surgeon characteristics, odds of AV fistula placement at high volume centers (>30 procedures per year) were more than three times greater than at low volume centers [odds ratio (OR) 3.26, 95% confidence interval (95% CI) 1.37 to 7.75, P = 0.008]. In addition, a strong clustering effect was present at the level of the surgeon (OR 1.55, 95% CI 1.19 to 2.03, P = 0.001) but not at the level of the surgical center, indicating an association with surgeon practice pattern. Barriers to AV fistula placement can exist at the levels of the surgeon and surgical center, respectively. Future strategies to improve AV fistula placement rates should target surgeons and surgical centers in addition to patients, nephrologists, and primary care providers.

Increasing AV Fistulae and Decreasing Dialysis Catheters: Two Aspects of Improving Patient Outcomes

Article

Feb 2007

Jeffrey Sands

Maximizing arteriovenous (AV) fistula prevalence and minimizing catheter use have become the dominant issues in hemodialysis vascular access management and offer the promise of improved patient outcomes with decreased overall expenditures. Recent efforts have increased AV fistula prevalence in the US to 42.9% with regional rates as high as 59.5% and with complementary declines in AV grafts. This should decrease access procedures but may not fully realize the potential reductions in mortality and cost possible if combined with catheter reduction. Successful catheter reduction requires similar approaches to those utilized in the Fistula First Program. Educating patients, the use of clearly defined protocols and updating payment systems to include chronic kidney disease care are crucial to continued progress. Expansion of the Fistula First Program to include a focus on decreasing catheter prevalence and complications should be considered as a requirement in the push toward the breakthrough targets of 66% AV fistula prevalence.

Comparison of Survival of Upper Arm Arteriovenous Fistulas and Grafts after Failed Forearm Fistula

Article

Jul 2007

Although arteriovenous fistulas are considered superior to grafts, it is unknown whether that is true in the subset of patients with a previous failed fistula. For investigation of this question, a prospective vascular access database was queried retrospectively to compare the outcomes of 59 fistulas and 51 grafts that were placed in the upper arm after primary failure of an initial forearm fistula. Primary access failure was higher for subsequent fistulas than for subsequent grafts (44 versus 20%; P = 0.006). Fistulas required more interventions than grafts before their successful use (0.42 versus 0.16 per patient; P = 0.04). The time to catheter-free dialysis was longer for fistulas than for grafts (131 versus 34 d; P < 0.0001) and was associated with more episodes of bacteremia before permanent access use (1.3 versus 0.4 per patient; P = 0.003). Cumulative survival (from placement to permanent failure) was higher for fistulas than for grafts when primary failures were excluded (hazard ratio 0.51; 95% confidence interval 0.27 to 0.94; P = 0.03), but similar when primary failures were included (hazard ratio 0.99; 95% confidence interval 0.61 to 1.62; P = 0.97). Fistulas required fewer interventions to maintain long-term patency for dialysis after maturation (0.73 versus 2.38 per year; P < 0.001). In conclusion, as compared with grafts, subsequent upper arm fistulas are associated with a higher primary failure rate, more interventions to achieve maturation, longer catheter dependence, and more frequent catheter-related bacteremia. However, once the access is usable for dialysis, fistulas have superior cumulative patency than do grafts and require fewer interventions to maintain patency.

Balancing Fistula First With Catheters Last

Article

Oct 2007
AM J KIDNEY DIS

The success of Fistula First nationwide has been accompanied by an unplanned increase in hemodialysis catheters. Complications related to prolonged hemodialysis catheter use include increased morbidity, mortality, and cost. We hypothesize that the national focus on increasing fistulas may have inadvertently diverted attention away from initiatives to decrease dependence on hemodialysis catheters. Based on a synthesis of guidelines, reviews, published evidence, and the authors' opinions, we propose that the national vascular access initiative be revised to have a dual goal of Fistula First and "Catheters Last." These goals are not mutually exclusive, but rather complementary. We recommend a systematic refocus on interventions that not only increase fistulas, but help avoid extended catheter use. Clearly, the ideal practice for hemodialysis vascular access remains early placement of fistulas with enough maturation time such that they can be used for initiating long-term hemodialysis therapy when the need arises. To effect this change, a reimbursement policy covering the costs associated with permanent access placement before the need for dialysis is essential. Individualized patient management strategies may consider such innovative approaches as initiating patients on peritoneal dialysis therapy or using nonautogenous grafts as bridge accesses in lieu of catheters. For patients who are dialyzing using catheters, immediate active planning for permanent access placement and removal of the catheter is necessary. In the same vein as Fistula First, the renal community should once again be galvanized in working together toward controlling the catheter epidemic in our dialysis population.

Hemodialysis vascular access: The Achilles ' heel remains

Article

Oct 2007

S J Schwab

Maintaining vascular access for hemodialysis remains a leading cause of patient morbidity. Surveillance and other technologies continue to improve, but the goal of dramatically improved AV access patency remains elusive.

Hemodialysis access failure: A call to actionrevisited

Abstract

No full-text available

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