Vascular Access Outcomes Research Articles

Vascular Access Outcomes in the Elderly Hemodialysis Population: A USRDS Study

Arteriovenous fistulae (AVF) are widely regarded as the preferred vascular access in hemodialysis (HD) patients due to their primary patency and patient survival benefits. Recent scholarship has suggested that the elderly population differs significantly from the general population in terms of inflammatory markers. What is more, recent studies have suggested that the elderly HD population is less likely to have an AVF placed as the initial vascular access compared to a younger cohort. The purpose of this study is to investigate the applicability of current vascular access guidelines to the elderly HD population. We hypothesized that the elderly HD population would derive less patency and survival benefit from AVF placement relative to arteriovenous graft (AVG) than the general population is known to derive. We performed a retrospective analysis using the US Renal Data System (USRDS) Wave II dataset to explore significant predictors of referral for intervention or access failure, and patient survival in the elderly US HD population using Cox regression corrected for race, gender, peripheral vascular disease, diabetes mellitus, and nutritional status. Of the 1471 HD patients with AVF or AVG, 764 patients were >65 years. Elderly diabetics had no significant mortality benefit from the use of AVF compared to AVG [odds ratio (OR) 1.34 (95% CI 0.92-1.95), p = 0.123]. Likewise, elderly nondiabetics had no significant mortality benefit from the use of AVF compared to AVG [OR 1.05 (95% CI 0.81-1.36), p = 0.735]. Elderly diabetics had no difference in odds for intervention referral for AVF compared to AVG [OR 1.49 (95% CI 0.76-2.9), p = 0.24]. Elderly nondiabetics had no difference in odds for intervention referral for AVF compared to AVG [OR 1.48 (95% CI 0.95-2.3), p = 0.08]. We conclude that the potential benefits derived from AVFs compared with AVGs and central venous catheters (CVC) may not apply universally. The recommendations of vascular access choice stipulated by national guidelines may need to be modified for elderly patients.

Fistula First Initiative

### Vascular Access Care before 1997 The arteriovenous fistula (AVF) was first described and used as a reliable form of hemodialysis (HD) vascular access (VA) by Brescia et al. (1) in 1966. Improvements in dialysis technology and the expansion of dialysis eligibility ( e.g. , inclusion of patients with diabetes) resulted in a rapid growth of the ESRD population. Many of these patients benefited from the development of prosthetic grafts when autogenous AVF were not feasible (2–5). In the mid-1980s, permanent catheters (central venous catheters [CVC]) in the internal jugular vein became a means of prolonging temporary access (6–8) and dramatically increased in use. The cumulative effect was a reduction in AVF use and an increase in graft and CVC use in the 1990s. This was associated with increased patient care costs; for example, up to 73% of patients were hospitalized to initiate dialysis and almost invariably had a temporary CVC inserted. VA was a major cause of morbidity and mortality (9), with HD access failure accounting for the most frequent cause of hospitalizations (10) and complications accounting for 14% of all ESRD expenses ($1 billion annually) (9). ### 1997 to 2003: Critical Events That Affected VA Care In an effort to improve VA outcomes, the National Kidney Foundation published the Kidney Disease Outcomes Quality Initiative (K/DOQI) Clinical Practice Guidelines for Vascular Access in 1997. The goal was to optimize management of VA through a set of evidence- and opinion-based based guidelines (10). In the following year, Centers for Medicare and Medicaid Services (CMS; the government-reimbursement agency for Medicare-insured patients) developed ESRD clinical performance measures (CPM) based on the K/DOQI VA guidelines, in response to the Balanced Budget Act of 1997 (11). VA-related CPM include ( 1 ) the proportion of HD patients with AVF, ( 2 ) the proportion of HD patients with a CVC, and ( 3 ) monitoring arteriovenous grafts for stenosis. The overriding goal …

Current Management of Vascular Access

Optimizing vascular access outcomes remains an ongoing challenge for clinical nephrologists. All other things being equal, fistulas are preferred over grafts, and grafts are preferred over catheters. Mature fistulas have better longevity and require fewer interventions, as compared with mature grafts. The major hurdle to increasing fistula use is the high rate of failure to mature of newly created fistulas. There is a desperate need for enhanced understanding of the mechanisms of failure to mature and the optimal type and timing of interventions to promote maturity. Grafts are prone to frequent stenosis and thrombosis. Surveillance for graft stenosis with preemptive angioplasty may reduce graft thrombosis, but recent randomized clinical trials have questioned the efficacy of this approach. Graft stenosis results from aggressive neointimal hyperplasia, and pharmacologic approaches to slowing this process are being investigated in clinical trials. Catheters are prone to frequent thrombosis and infection. The optimal management of catheter-related bacteremia is a subject of ongoing debate. Prophylaxis of catheter-related bacteremia continues to generate important clinical research. Close collaboration among nephrologists, surgeons, radiologists, and the dialysis staff is required to optimize vascular access outcomes and can be expedited by having a dedicated access coordinator to streamline the process. The goal of this review is to provide an update on the current status of vascular access management.

Vascular Access Outcomes and Medication Use: A USRDS Study

Several medications have been proposed to improve hemodialysis (HD) vascular access outcomes based on potentially favorable anticoagulant, antiplatelet, or pleiotropic properties. The purpose of this study was to evaluate the relationship between medication use and vascular access patency in a group of HD patients. We conducted a historical cohort study of the US Renal Data System Dialysis Mortality and Morbidity Wave II study to identify patients with an arteriovenous fistula (AVF), polytetrafluoroethylene (PTFE) graft, or a permanent catheter for vascular access. Cox regression analysis, adjusted for age, gender, race, history of coronary artery disease, peripheral vascular disease, or coronary artery bypass graft, was used to model the hazard ratio (HR) of permanent vascular access failure. Of the 2001 HD patients in the Wave II study, 901 (45%) were included in the analysis. PTFE graft patency was greater for males (HR, 0.73; 95% CI 0.53-1.00, p = 0.05) and for older individuals (HR, 0.99; 95% CI 0.98-1.00, p = 0.02). Treatment with antiplatelet medications, ticlopidine and dipyridamole (HR, 3.54; 95% CI 1.07-11.76; p = 0.04), or aspirin (HR, 2.49; 95% CI 1.31-4.73; p = 0.005) was associated with significantly worse AVF patency. Antiplatelet agents had a significant negative association with access patency in this cohort. In contrast to other published data, it was difficult to identify any beneficial effect of specific medications on access patency.

Vascular Access Outcomes as a Predictor of Development of Chronic Allograft Nephropathy

Introduction The vascular condition influences the outcomes of arteriovenous fistula (AVF) surgery. However, it has not been established how it influences the outcomes of renal transplantation and the development of chronic allograft nephropathy (CAN). The aim of this study was to define the relationship between AVF failure in the pretransplant period and the development of CAN. Patients and methods In this study we included all patients who underwent AVF surgery and then first kidney allotransplantations from January 1, 1999 to December 31, 2002. Patients were divided into two groups according to the AVF surgery outcomes: group 1 ( n = 45, mean age 50 ± 13 years, male/female ratio 27/18) had no vascular access complications and were dialysed through a native AVF. Group 2 ( n = 39, mean age 51 ± 11 years, male/female ratio 17/22) had additional interventions due to AVF failure. We analyzed the incidence of CAN in both groups. Results During the follow-up period CAN was observed in five patients in group 1 and 11 patients in group 2 (11,1% vs 28,2%, P < .05). There was a statistically significant relationship between CAN and acute rejection episodes ( P < .005) and diabetes mellitus ( P < .05). Conclusion Failures of arteriovenous fistulas in hemodialysis patients were associated with an increased incidence of CAN in the posttransplant period.

Impact of pre-operative venography on the planning and outcome of vascular access for hemodialysis patients

Pre-operative venous mapping has increased dramatically in most dialysis units since the Dialysis Outcome Quality Initiative (DOQI) guidelines recommended a native arteriovenous venous fistula (AVF) rather than a graft for hemodialysis (HD) access procedures. However, there are conflicting consequences as a result of this policy. Some studies have showed that routine mapping has resulted in a marked increase in maturation rate while others have observed the reverse. This study aimed to evaluate the impact of pre-operative venography on the planning and outcome of AVF for our HD patients. A prospective study was performed on all patients with end-stage renal disease (ESRD) who had HD access procedures and pre-operative venography between October 2003 and November 2005. Upper limb venography was done for all patients except those that required primary access and had visible veins. All patients had HD immediately after the venography. Access procedure selection was based on the result of the venography. The complications of venography, the surgical procedure and the outcome were recorded. One hundred and twenty-nine patients with ESRD who had pre-operative venography were included in this study. They were mostly middle age (mean age +/- SD = 41 +/- 15.5 yrs) with a high rate of diabetes mellitus (53%). No single complication was reported. A graft was placed in six patients (5%) only. Unsuccessful surgical exploration was 0%. Early failure was in 10 patients (8%). Pre-operative venography resulted in an increase in the number of AVFs. It can improve the results of HD access procedures by selecting the most suitable veins.

Relationship between Clinical Outcomes and Vascular Access Type among Hemodialysis Patients with Staphylococcus aureus Bacteremia

The association between hemodialysis vascular access type, costs, and outcome of Staphylococcus aureus bacteremia (SAB) among patients with ESRD remains incompletely characterized. This study was undertaken to compare resource utilization, costs, and clinical outcomes among SAB-infected patients with ESRD by hemodialysis access type. Adjusted comparisons of costs and outcomes were based on multivariable linear regression and multivariable logistic regression models, respectively. A total of 143 hospitalized hemodialysis-dependent patients had SAB at Duke University Medical Center between July 1996 and August 2001. A total of 111 (77.6%) patients were hospitalized as a result of suspected bacteremia; 32 (22.4%) were hospitalized for other reasons. Of the 111 patients, 59.5% (n = 66) had catheters as their primary access type, 36% (n = 40) had arteriovenous (AV) grafts, and 4.5% (n = 5) had AV fistulas. Patients with fistulas were excluded from analyses because of small numbers. Patients with catheters were more likely to be white, had shorter dialysis vintage, and had higher Acute Physiology and Chronic Health Evaluation II scores compared with patients with grafts. Unadjusted 12-wk mortality did not significantly differ between patients with catheters compared with patients with grafts (22.7 versus 10.0%; P = 0.098); neither did 12-wk costs differ by access type ($22,944 +/- 18,278 versus $23,969 +/- 13,731, catheter versus graft; P > 0.05). In adjusted analyses, there was no difference in 12-wk mortality (odds ratio 1.63; 95% confidence interval 0.29 to 9.02; catheter versus graft) or 12-wk costs (means ratio 0.84; 95% confidence interval 0.60 to 1.17; catheter versus graft) among SAB-infected patients with ESRD on the basis of hemodialysis access type. Twelve-week mortality and costs that are associated with an episode of SAB are high in hemodialysis patients, regardless of vascular access type. Efforts should focus on the prevention of SAB in this high-risk group.

Design of the Dialysis Access Consortium (DAC) clopidogrel prevention of early AV fistula thrombosis trial

The Dialysis Access Consortium (DAC) was developed to investigate interventions to improve hemodialysis vascular access outcomes. The autogenous arteriovenous fistula created by direct connection of native artery to vein is the recommended vascular access for hemodialysis. However, it fails frequently due to clotting after surgery. The DAC Early AV Fistula Thrombosis Trial tests the hypothesis that clopidogrel can prevent early fistula failure and increase the number of fistulas that ultimately become usable for hemodialysis access. This is one of two initial and concurrent trials being performed by the DAC. The companion trial investigates pharmacologic approaches to prevent venous stenosis leading to AV graft failure. This is a multicenter, randomized, double-blind, placebo-controlled trial that will enroll 1,284 patients over four years. Patients undergoing creation of a new native arteriovenous (AV) fistula are randomized to treatment with clopidogrel or placebo for six weeks following fistula creation surgery. The primary outcome is fistula patency at six weeks. The major secondary outcome is fistula suitability for dialysis. This paper examines key aspects of this study that have broad relevance to trial design including: 1) the selection of an intermediate event as the primary outcome, 2) timing of the intervention to balance efficacy and safety concerns, 3) ethical considerations arising from required modifications of concomitant drug therapy, and 4) choosing an efficacy or effectiveness evaluation of the intervention. This is the first, large, multicenter trial evaluating a pharmacologic approach to prevent early AV fistula failure and promote more usable fistulas for hemodialysis. The methodologic challenges identified and addressed during the development of this trial should help to inform the design of future vascular access trials, and are relevant to clinical trials addressing a wide range of questions.

Dialysis Outcomes and Practice Patterns Study (DOPPS) data on medications in hemodialysis patients

<i>Background:</i> Medications affect many measures of hemodialysis patients' well-being. <i>Methods:</i> The Dialysis Outcomes and Practice Patterns Study (DOPPS) has evaluated the use of hydroxymethyl glutaryl coenzyme A reductase inhibitors (statins), analgesics, antidepressants, and multivitamins. Additionally, DOPPS has reported on the associations between vascular access outcomes and related medications. <i>Results:</i> Prescription of statins varied widely across countries, with the highest use in the United States. Patients prescribed statins had lower risk of cardiac and noncardiac causes of mortality than those who were not prescribed statins. DOPPS data also show that statins are underprescribed relative to recent Kidney Disease Outcomes Quality Initiative guidelines. No guidelines have been established for analgesic use, but high pain levels self-reported by hemodialysis patients suggest opportunities for improved pain management strategies. Guidelines for analgesic use in dialysis patients may help balance improved quality of life against potential side effects of analgesics. Medical and patient questionnaires show that depression in hemodialysis patients is common, frequently underdiagnosed, usually untreated, and associated with increased rates of mortality and hospitalization. Calcium channel blockers were associated with improved primary graft patency, aspirin with improved secondary graft patency, and angiotensin-converting enzyme inhibitors with improved secondary fistula patency. All 3 medications were associated with significantly decreased relative risk for access failure. There is large country variation in multivitamin use, with significantly higher use in the United States compared with Europe and Japan. Patients taking multivitamins had lower mortality risk than patients not taking multivitamins. <i>Conclusion:</i> DOPPS findings on medications indicate that prospective trials are needed before guidelines can be developed for appropriate medication use in these different therapeutic categories.

Dialysis Outcomes and Practice Patterns Study (DOPPS) data on medications in hemodialysis patients

Medications affect many measures of hemodialysis patients' well-being. The Dialysis Outcomes and Practice Patterns Study (DOPPS) has evaluated the use of hydroxymethyl glutaryl coenzyme A reductase inhibitors (statins), analgesics, antidepressants, and multivitamins. Additionally, DOPPS has reported on the associations between vascular access outcomes and related medications. Prescription of statins varied widely across countries, with the highest use in the United States. Patients prescribed statins had lower risk of cardiac and noncardiac causes of mortality than those who were not prescribed statins. DOPPS data also show that statins are underprescribed relative to recent Kidney Disease Outcomes Quality Initiative guidelines. No guidelines have been established for analgesic use, but high pain levels self-reported by hemodialysis patients suggest opportunities for improved pain management strategies. Guidelines for analgesic use in dialysis patients may help balance improved quality of life against potential side effects of analgesics. Medical and patient questionnaires show that depression in hemodialysis patients is common, frequently underdiagnosed, usually untreated, and associated with increased rates of mortality and hospitalization. Calcium channel blockers were associated with improved primary graft patency, aspirin with improved secondary graft patency, and angiotensin-converting enzyme inhibitors with improved secondary fistula patency. All 3 medications were associated with significantly decreased relative risk for access failure. There is large country variation in multivitamin use, with significantly higher use in the United States compared with Europe and Japan. Patients taking multivitamins had lower mortality risk than patients not taking multivitamins. DOPPS findings on medications indicate that prospective trials are needed before guidelines can be developed for appropriate medication use in these different therapeutic categories.

Vascular access for hemodialysis: 2004 and beyond.

Developments in vascular access are accruing rapidly. The last systematic Kidney Disease Outcomes Quality Initiative guidelines review took place in 2000. The purpose of this review is to update several major areas in which clear progress has been made. A major 'Fistula First Initiative' in the USA is an attempt to increase markedly the fraction of patients receiving an autologous arteriovenous fistula as opposed to a graft. Preoperative mapping to evaluate veins and artery may permit construction of arteriovenous fistula in up to 70% of all patients, thereby reducing access thrombosis, infection, and perhaps increasing survival of patients. Although a number of different synthetic materials have been tried, none seems to have any definite advantage over plain expanded polytetrafluoroethylene for constructing synthetic bridge grafts. Two developments may influence practice: use of composite self-sealing grafts that can be used within hours may eliminate the need for temporary catheters; and use of nitinol surgical clips may reduce endothelial trauma and improve patency. Large-bore catheters can deliver blood flows of over 400 ml/min initially, but they are prone to progressive occlusion. Optimal means of using a fibrinolytic to preserve flow must be evaluated. Surveillance techniques are undergoing rapid re-evaluation. Finally, a variety of antibiotic lock techniques are being evaluated for their ability to prevent catheter-related infections. Greater efforts must be made to establish pre-end-stage renal disease programs to educate and prepare patients for hemodialysis and improve arteriovenous fistula placement rates, and to encourage clinicians to re-examine their current clinical practices and dedicate themselves to improving vascular access outcomes.

Predictors of successful arteriovenous fistula maturation

Background: Understanding the factors associated with successful arteriovenous fistula (AVF) maturation may provide an opportunity to improve vascular access outcomes. Methods: This prospective cohort study enrolled 348 hemodialysis patients receiving an AVF and followed them until ascertainment of successful AVF maturation. Multivariable logistic regression was used to develop (1) explanatory models of factors associated with AVF success and (2) models for predicting success based on sociodemographic and comorbidity profiles. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the discriminative ability of our predictive model. Predictive probabilities of AVF maturation under the assumption of optimal surgical technique defined by explanatory models were calculated. Results: A total of 55.5% of AVFs successfully matured. A history of stroke or transient ischemic attack, increasing age, and dependence on dialysis at the time of access placement were associated with lower probabilities of maturation. Of potentially modifiable variables, maturation was associated with greater intraoperative doses of heparin, use of large-diameter veins, and mean arterial pressure of 85 mm Hg or greater. Using optimal surgical technique, the probability of successful AVF maturation would have been as high as 84%. A predictive logistic regression model had moderate ability to predict AVF maturation under optimal surgical therapy with an area under the ROC curve of 0.69. Conclusion: Surgical technique potentially may be modified to yield a greater probability of successful AVF maturation. Predictive probabilities of successful AVF maturation under optimal surgical technique reinforce the view that functioning AVFs can be achieved in a large proportion of hemodialysis patients, consistent with experience in selected regions of the United States and abroad.

Vascular access and patient outcomes in hemodialysis: questions answered in recent literature.

Hemodialysis is not possible without access to the vascular system to provide an adequate and reliable source of blood flow through the hemodialyzer. Since maintenance hemodialysis therapy became a reality in the latter half of the twentieth century, no vascular access has exceeded the success and reliability of arteriovenous fistulae (AVF). They have the lowest infection and thrombosis rates, have the longest patency rates, and are associated with the best morbidity and mortality outcomes of any access modality. In the United States, the majority of patients starting hemodialysis do not have a primary AVF, which may explain why vascular access complications represent almost 20% of the total spending for hemodialysis. In addition, as much as 50% of hospitalization costs for end-stage renal disease are related to access issues. Every effort must be directed in the U.S. as well as elsewhere to promote the use of AVF whenever possible. In some European countries, more than 90% of patients have AVF as their hemodialysis access when nephrologists perform placement of vascular access. Already, some programs in the U.S. have recognized the need for trained nephrologists to provide these services. U.S. interventional nephrologists should be given the opportunity to learn AVF placement procedures to emulate their European counterparts, and thus improve U.S. dialysis outcomes.

Increasing arteriovenous fistulas in hemodialysis patients: Problems and solutions

Increasing arteriovenous fistulas in hemodialysis patients: Problems and solutions

Hemodialysis vascular access preferences and outcomes in the Dialysis Outcomes and Practice Patterns Study (DOPPS)

Synthetic grafts have generally been found to exhibit lower survival rates and higher complication rates than native arteriovenous fistulae. We investigated whether survival of grafts relative to fistulae was better in facilities with a preference for grafts, hypothesizing that such facilities may place more grafts because grafts produced superior outcomes. The study was based on a national U.S. sample of 133 hemodialysis facilities participating in the Dialysis Outcomes and Practice Patterns Study (DOPPS), a prospective, observational study of dialysis treatment practices and outcomes. Vascular access preferences were ascertained from medical directors, nurse managers, and actual practice within each facility (% graft use among prevalent patients). Logistic regression was used to model the odds ratio (OR) of graft placement (vs. fistula) and Cox regression was used to model time from access creation to initial failure. Grafts were preferred by 21% of medical directors and 40% of nurse managers. Patients in facilities in which the medical director or nurse manager expressed a preference for grafts were more than twice as likely to have a graft than a fistula (AOR = 2.3, P < 0.01; reference group = facilities that did not prefer grafts), suggesting that facility preferences influence the type of access created. Overall, grafts were more prevalent than fistulae in dialysis facilities, but displayed a higher relative risk of failure (RR 1.33, P < 0.0001). However, the risk of graft versus fistula failure did not vary by expressed preference of the medical director: the relative risk of graft versus fistula failure was 1.39 in facilities in which the medical director preferred grafts and 1.39 in facilities in which the medical director preferred fistulae. Moreover, the relative risk of graft versus fistula failure was 1.57 in facilities that used more than the median percentage of grafts and 1.19 in facilities that used less than the median percentage of grafts. No evidence was found that graft outcomes are superior in facilities that prefer grafts to fistulae. The observed variation in vascular access practice patterns suggests opportunities for quality improvement if optimal practices can be defined.

Systemic barriers to improving vascular access outcomes.

Vascular access dysfunction is the most frequent cause of hospitalization for end-stage renal disease (ESRD) patients. Our system of vascular access care and industry standards developed for historic reasons have resulted in a haphazard approach to access management. The Dialysis Outcome Quality Initiative has provided a road map for improving vascular access management. However, despite widespread acceptance, these recommendations are not routinely followed. This is largely the result of inertia coupled with systemic barriers to improving access outcomes. These barriers include lack of funded pre-ESRD care and preoperative imaging, lack of reimbursement for access monitoring, unavailable surgical and interventional suites, erosion of the real value of the composite rate, bundling of additional new services without rate adjustment, poor accountability of surgeons and hospitals, and a reimbursement system that rewards procedures and, in particular, graft and catheter placement. Currently, Center for Medicare and Medicaid Services is reevaluating the composite rate and its included bundle of services. To provide the best access care with the fewest complications while insuring multidisciplinary involvement and accountability, a realistic appraisal and realignment of incentives must be developed to insure improvement of access care in the United States.

Vascular access use and outcomes: results from the DOPPS.

Vascular access use and outcomes: results from the DOPPS.

Effect of preoperative sonographic mapping on vascular access outcomes in hemodialysis patients

Current DOQI guidelines encourage placing arteriovenous (AV) fistulas in more hemodialysis patients. However, many new fistulas fail to mature sufficiently to be usable for hemodialysis. Preoperative vascular mapping to identify suitable vessels may improve vascular access outcomes. The present study prospectively evaluated the effect of routine preoperative vascular mapping on the type of vascular accesses placed and their outcomes. During a 17-month period, preoperative sonographic evaluation of the upper extremity arteries and veins was obtained routinely. The surgeons used the information obtained to plan the vascular access procedure. The types of access placed, their initial adequacy for dialysis, and their long-term outcomes were compared to institutional historical controls placed on the basis of physical examination alone. The proportion of fistulas placed increased from 34% during the historical control period to 64% with preoperative vascular mapping (P < 0.001). When all fistulas were assessed, the initial adequacy rate for dialysis increased mildly from 46 to 54% (P = 0.34). For the subset of forearm fistulas, the initial adequacy increased substantially from 34 to 54% (P = 0.06); the greatest improvement occurred among women (from 7 to 36%, P = 0.06) and diabetic patients (from 21 to 50%, P = 0.055). In contrast, the initial adequacy rate of upper arm fistulas was not improved by preoperative vascular mapping (59 vs. 56%, P = 0.75). Primary access failure was higher for fistulas than grafts (46.4 vs. 20.6%, P = 0.001), but the subsequent long-term failure rate was higher for grafts than fistulas (P < 0.05). Moreover, grafts required a threefold higher intervention rate (1.67 vs. 0.57 per year, P < 0.001) to maintain their patency. The overall effect of this strategy was to double the proportion of patients dialyzing with a fistula in our population from 16 to 34% (P < 0.001). Routine preoperative vascular mapping results in a marked increase in placement of AV fistulas, as well as an improvement in the adequacy of forearm fistulas for dialysis. This approach resulted in a substantial increase in the proportion of patients dialyzing with a fistula in our patient population. Fistulas have a higher primary failure rate than grafts, but have a lower subsequent failure rate and require fewer procedures to maintain their long-term patency.

The Dialysis Outcomes and Practice Patterns Study (DOPPS): How Can We Improve the Care of Hemodialysis Patients?

Outcomes among dialysis patients vary considerably internationally and across regions within the United States. The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a large, prospective, observational study of representative samples of hemodialysis patients in France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States. The DOPPS collects a wealth of data regarding the patients' demographic characteristics, medical histories, laboratory values, prescriptions, dialysis unit practices, and outcomes. The study seeks to clarify which dialysis practices contribute to improved mortality rates, hospitalization rates, health related quality of life, and vascular access outcomes, after adjusting for the effects of comorbid disease and demographic variables. Over 18,000 patients have been enrolled to date. This paper describes the initial findings and outlines the plans to expand the trial.

Improvement in hemodialysis vascular access outcomes in a dedicated access center.

There are more than 300,000 end-stage renal disease (ESRD) patients in the United States, with those on hemodialysis requiring vascular access for dialysis treatment. According to the 1999 annual report of the U.S. Renal Data System (USRDS), the leading cause of morbidity in this patient population is related to vascular access placement and the resultant complications. Vascular access procedures account for more than 10% of the annual ESRD budget and are conservatively estimated at $1 billion annually. The impact of dysfunctional vascular access on physician time, health care resources, and patient quality of life is profound. In 1997 I opened a freestanding, dedicated access center for the diagnosis and treatment of access-related disorders. This article summarizes the experience of this center. In our free-standing dialysis access center, a large referral base has been established consisting of 30 dialysis centers with approximately 2000 patients. During the 27 months from October 1997 to December 1999, 1087 patients were treated. These patients received 2862 access procedures (2.6 procedures/patient). Annualized, this gives a dysfunction rate of 1.15 episodes/patient/year at risk. Endovascular declotting procedures were performed 1282 times (45%) with a success rate (defined as one uneventful hemodialysis following the procedure) of 93% (1187/1282). Prospective angiography followed by percutaneous transluminal angioplasty was performed 703 times (24%). This procedure was successful 695 times for a success rate of 99%. There were 644 (23%) catheter procedures performed consisting of catheter placements, catheter exchanges through new or old tracts, and catheter removals. The success rate for catheter procedures was 99.1%. Complication rates were extremely low, both for major and minor complications, exceeding all published standards. Hemodialysis vascular access can be optimized in a freestanding, focused, outcomes-driven outpatient access center. Outcomes can meet or exceed the National Kidney Foundation Dialysis Outcomes Quality Initiative (NKF-DOQI) guidelines for vascular access while at the same time providing the patient with an outpatient procedure and the referring dialysis unit and nephrologist with an efficient, effective mode of patient care.