Clinical outcomes that are associated with the various

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1 Clinical Course Associated with Vascular Access Type in a National Cohort of Adolescents Who Receive Hemodialysis: Findings from the Clinical Performance Measures and US Renal Data System Projects Jeffrey J. Fadrowski,* Wenke Hwang, Diane L. Frankenfield, Barbara A. Fivush,* Alicia M. Neu,* and Susan L. Furth* *Department of Pediatrics, Johns Hopkins University School of Medicine, Centers for Medicare & Medicaid Services, and Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins Medical Institutions, Baltimore, Maryland; and Department of Public Health, Wake Forest University School of Medicine, Winston-Salem, North Carolina Limited research has described clinical outcomes that are associated with the type of vascular access in pediatric patients who receive maintenance hemodialysis. This retrospective cohort study examined prevalent pediatric patients who were aged 12 to <18 yr and identified in the 2000 ESRD Clinical Performance Measures Project as receiving in-center hemodialysis. Vascular access type as of December 31, 1999, was identified. These patients were linked with 1 yr of data (January 1, 2000, through December 31, 2000) from US Renal Data System standard analytic files that allow for the comparison of rates of hospitalizations and access complications by access type. Of the 418 patients who met inclusion criteria, the mean age was 15.6 yr, 53% were male, 49% were white, the mean time on dialysis was 22 mo, and 42% had a structural/urologic cause of ESRD; 42% of patients had an arteriovenous graft or fistula, and 58% had a vascular catheter. Patients with a vascular catheter as compared with those with a graft or fistula had the following adjusted relative risks (95% confidence interval): 1.84 (1.38 to 2.44) for hospitalization for any cause, 4.74 (2.02 to 11.14) for hospitalization as a result of infection, and 2.72 (2.00 to 3.69) for a complication of vascular access. Vascular catheters are the predominant access type in adolescent patients who receive maintenance hemodialysis and are associated with significantly more hospitalizations and complications. Clin J Am Soc Nephrol 1: , doi: /CJN Clinical outcomes that are associated with the various types of vascular access in adults who have ESRD and receive maintenance hemodialysis have been well described. Studies have demonstrated repeatedly that arteriovenous fistulas (AVF) have increased longevity and decreased complication rates in adults as compared with arteriovenous grafts (AVG) and vascular catheters (1 14). This evidence has contributed to AVF s being the preferred hemodialysis access type in adults. This has been emphasized by the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI) Clinical Practice Guidelines for vascular access and the Centers for Medicare & Medicaid Services (CMS) Fistula First, the National Vascular Access Improvement Initiative (15,16). Received February 14, Accepted June 14, Published online ahead of print. Publication date available at The interpretation and reporting of the data herein are the responsibility of the authors and in no way should be seen as an official policy or interpretation of the US government or the Centers for Medicare & Medicaid Services. Address correspondence to: Dr. Jeffrey J. Fadrowski, Park 335, 600 N. Wolfe Street, Baltimore, MD Phone: ; Fax: ; jfadrow1@jhmi.edu A significant number of pediatric patients receive hemodialysis as renal replacement therapy. Of the 2271 prevalent dialysis patients aged 0 to 19 yr in the US Renal Data System (USRDS) reported in 2003, approximately 60% received hemodialysis. In the 15- to 19-yr age group, 70% received hemodialysis. Among incident pediatric patients who were aged 0 to 19 yr and initiated dialysis from 1993 to 2003, the percentage of patients who were on hemodialysis increased from 54% in 1993 to 59% in 1998 and 62% in 2003 (17). Vascular catheters are the predominant form of vascular access in the pediatric hemodialysis population. The 2004 ESRD Clinical Performance Measures (CPM) Project reported vascular access type in a national cohort of 678 pediatric patients who were receiving in-center hemodialysis as of December 31, Twenty-seven percent were dialyzed with an AVF, 12% with an AVG, and 60% with a catheter. Examination of vascular type in adolescent patients during the past 5 yr of ESRD CPM Projects reveals a steady increase in the use of vascular catheters (18,19). Limited research has examined clinical outcomes that are associated with the various access types in children. The majority of the studies published are retrospective and center or region specific (20 27). Limited data and pediatric-specific challenges regarding vascular access complicate the determination of the applicability and the relevance of the adult-based Copyright 2006 by the American Society of Nephrology ISSN: /

2 988 Clinical Journal of the American Society of Nephrology Clin J Am Soc Nephrol 1: , 2006 NKF-K/DOQI Clinical Practice Guidelines to the pediatric population; forthcoming NKF-K/DOQI Pediatric Vascular Access Clinical Practice Guidelines will address such issues. To further the understanding of vascular access patterns and associated clinical complications in the pediatric population, this study examines a national cohort of adolescent hemodialysis patients. Materials and Methods Design, Setting, and Participants This is a retrospective cohort study using merged data from two national databases in the United States: CMS s ESRD CPM Project and the USRDS, which collect clinical and demographic information, as well as data regarding hospitalization and survival of patients who receive hemodialysis. CMS began routinely assessing the quality of care that is provided to adult ESRD patients in 1994, and this data collection now is known as the ESRD CPM Project. Details of the methods of data collection for the ESRD CPM Project have been reported elsewhere (18,28). The USRDS maintains data on all incident and prevalent ESRD patients in the United States, including demographic, laboratory, insurance, and medical data. The USRDS collects additional data on dialysis claims and information on treatment history and hospitalization events (17). A limited data set was created by linking the USRDS patient identification number in the USRDS standard analytic file with ESRD CPM data collected in 2000 (for October through December 1999). At the time of this analysis, the USRDS standard analytic file was updated through January These data were examined to describe clinical outcomes, including hospitalizations, procedures, and mortality associated with the various types of vascular access in the pediatric age group. The 2000 ESRD CPM Project year was the first year that data collection was expanded to include all adolescent ( 12 to 18 yr of age) patients who were receiving in-center hemodialysis in the United States as of December 31, 1999 (corresponding with ESRD CPM Project Year 2000). From this cohort, patients were included in this study when their vascular access type was indicated within the ESRD CPM Project and they were identified in the USRDS. Variables of Interest and Methods The independent variable of interest was type of vascular access. These data were obtained from the ESRD CPM patient data file, which described the type of vascular access in use on or between October 1, 1999, and December 31, 1999, the period of data collection for the 2000 ESRD CPM Project year. Access type choices that were included on the 2000 ESRD CPM data collection form were AVF, synthetic AVG, bovine graft, vascular catheter, other, or unknown. For patients who met inclusion criteria, 12 mo of USRDS inpatient hospitalization and outpatient records were available for examination. A timeline was created for the year of follow-up, to account for possible switches in access type and facilitate a time-at-risk analysis. The beginning of the observation period was January 1, 2000, and the end was December 31, Patients were censored for kidney transplant and death. Patients were reassigned to a new access type according to the following rules: (1) When AVF creation was listed in the procedure codes, the patient was reassigned to AVF 12 wk after the procedure; (2) when AVG creation was listed in the procedure codes, the patient was reassigned to AVG 3 wk after the procedure; and (3) when a vascular catheter was listed in the procedure codes, the patient was reassigned to a vascular catheter on the day of the procedure. To assess the validity of reported access type in the ESRD CPM Project, we compared the access type indicated for patients who were present in both the 2000 and the 2001 ESRD CPM study, and this also was correlated with hospitalization and procedure claims in the USRDS. Approximately 10% of patients who were categorized as having an AVF or an AVG in the ESRD CPM 2000 Project year subsequently were categorized in the opposite category in the ESRD CPM 2001 Project year, with no procedure codes to support such a switch. For example, a patient with an AVF in the ESRD CPM 2000 Project year was listed as having an AVG in the ESRD CPM 2001 Project year, with no supporting or confirming evidence in the USRDS data file for this switch. For access types in question (graft versus fistula), USRDS procedure records for the year before January 2000 were examined in an attempt for clarification but with little success. Given that the ESRD CPM data collection forms and the administrative data that are used by the USRDS to create the standard analytic data files commonly are completed by administrative and dialysis staff (nurses or social workers) who likely are not assessing the patient s access regularly, potential for significant misclassification of subcutaneous access types (AVG versus AVF) existed, and our exploratory analyses supported this. Therefore, we chose to collapse the categories of AVF and AVG into a single category, graft/fistula (hereafter referred to as permanent access ). The patient data file from the ESRD CPM Project provided relevant demographic and clinical variables, including age, gender, body size, race, ethnicity, assigned cause of ESRD, date of first dialysis treatment, serum albumin, hemoglobin, and single-pool Kt/V (spkt/v; Daugirdas II method). Underlying causes of ESRD were stratified into the following categories: Congenital/urologic, glomerulonephritis, focal segmental glomerulosclerosis, systemic lupus erythematosus, and other. For serum albumin, hemoglobin, and spkt/v, up to three values were available from data collection during the study period of October, November, and December 1999; an average was taken of these values. For the purpose of regression analyses, covariates were dichotomized as follows: Race, black versus nonblack; dialysis vintage, 6 moversus greater 6 mo; mean hemoglobin, 11 versus 11 g/dl; mean serum albumin, 3.5/3.2 versus 3.5/3.2 g/dl (bromcresol green/bromcresol purple laboratory methods). Dependent variables included all-cause hospitalization, infectionrelated hospitalization, and access-related complications. Hospitalizations were assigned as infection related when the International Classification of Diseases, Ninth Revision code 038.xx (septicemia) or (bacteremia) was listed as either the principal or the secondary diagnosis in the USRDS inpatient claims file. The following inpatient or hospital outpatient procedures were identified within the USRDS standard analytic files to aid in the classification of vascular access, censoring, and determination of an accessrelated complication: Transplant of kidney, revision of vascular procedure, revision/removal of arteriovenous shunt for renal dialysis, other revision of vascular procedure, arteriovenostomy for renal dialysis, insertion/replacement of vessel to vessel cannula, venous catheterization for renal dialysis, and thrombectomy/embolectomy. Complications of vascular access were determined as follows: (1) Thrombectomy/embolectomy of any access type and (2) vascular catheter placed in a patient with a permanent access and considered as a complication of a permanent access. In addition, single procedures that were 7 d apart were considered as separate complications, multiple procedures within the same 7-d period were considered one complication, and vascular catheters that were placed at the time of a kidney transplant were not considered a complication of vascular access or included in the analysis. Statistical Analyses The crude incidence rates of all-cause hospitalization, infectionrelated hospitalization, and access complications were calculated by

3 Clin J Am Soc Nephrol 1: , 2006 Vascular Access Outcomes in Adolescents 989 dividing the number of events by person-year at risk according to access type. Incidence rate ratios and 95% confidence intervals (CI) then were determined. The relative risks for the above outcomes by access type, adjusting for clinical characteristics, were obtained by multiple regression modeling using general estimating equations with robust variance estimation. In addition, sensitivity analyses were performed according to the following algorithm. The USRDS payer history file was examined for each patient to determine whether any potential gaps in Medicare coverage were present. Relative risks then were determined using the same multiple regression modeling as the original analysis but on two restricted population samples: One model excluded any patient with a potential gap in Medicare coverage during the year of follow-up, and one model excluded patients with a gap in coverage of 60 d. All analyses were performed using SAS version 9 (SAS Institute, Cary, NC). Results A total of 433 prevalent adolescent patients who were receiving hemodialysis were identified in the 2000 ESRD CPM Project Year. Of this cohort, 418 patients had the type of vascular access identified in the ESRD CPM Project and were identified in the USRDS and therefore were included in subsequent analyses. As of December 31, 1999, 175 (42%) patients had a vascular catheter and 243 (58%) had a permanent access. Patient characteristics are presented in Table 1. Patients had a mean age of 15.6 yr (SD 1.6); 53% were male, 49% were white, 22% were of Hispanic ethnicity, and 42% had a congenital/urologic cause for their ESRD. The mean dialysis vintage was 22 mo (SD 30). The mean hemoglobin was 11.0 g/dl (1.6), the mean serum albumin was 3.85 g/dl (0.53)/3.61 g/dl (0.52; bromcresol green/bromcresol purple methods), and the mean spkt/v was 1.49 (0.46). When patients were stratified by their type of vascular access, patients with a vascular catheter, as compared with those with a permanent access, were significantly more likely to be younger, to be female, and to have been receiving hemodialysis for a shorter period of time. Patients with a vascular catheter also had a significantly lower hemoglobin and serum albumin as compared with those with a permanent access and were significantly more likely to have a spkt/v 1.2. There was no significant difference in body mass index z score categories, race, ethnicity, cause of ESRD, or occurrence of kidney transplantation by vascular access type. Figure 1 describes patterns in vascular access during the 1 yr of follow-up. The majority (86%) of patients had no change in their vascular access type during the course of follow-up. Eight (2% of total cohort) patients with a catheter switched to a permanent access. Forty-eight (11% of total cohort) patients with a permanent access switched to a catheter. Three patients, all starting the follow-up period with a catheter, had multiple access switches. Of the total sample, 54 (13%) patients received kidney transplantation in Of the patients who received a transplant, 28 (52%) had a vascular catheter and 26 (48%) had a permanent access. Patients who received a transplant had been receiving dialysis for 20 mo (SD 22.5) on average, those with a catheter for 19 mo (SD 27.4), and those with a permanent access for 20 mo (16). Patients with vascular catheters had 1.62 all-cause hospitalizations per person-year at risk, compared with 0.91 hospitalizations in patients with a permanent access (Table 2). The rate of hospitalization for infections was significantly higher in patients with a vascular catheter (0.16 per person-year), compared with those with a permanent access (0.03). The complication Table 1. Patient characteristics, 2000 ESRD CPM Project Year a Characteristic Total Population (n 418) Catheter (n 175) Stratified Population Permanent Access (n 243) P Mean age (yr SD ) 15.6 (1.6) 15.4 (1.6) 15.7 (1.5) Male (%) White (%) Hispanic ethnicity (%) Congenital/urologic disease as cause of ESRD (%) Dialysis vintage (mo SD ) 22 (30) 14.7 (26) 26.8 (32) Mean hemoglobin (g/dl SD ) 11.0 (1.6) 10.6 (1.6) 11.3 (1.4) Mean hemoglobin 11.0 g/dl (%) Mean serum albumin 3.5/3.2 g/dl (%) b Mean spkt/v (SD) 1.5 (0.5) 1.4 (0.5) 1.5 (0.4) Mean spkt/v 1.2 (%) BMI z score categories (%) to Received transplant during year of follow-up (%) a BMI, body mass index; CPM, Clinical Performance Measures; spkt/v, single-pool Kt/V. b Bromcresol green/bromcresol purple laboratory method.

4 990 Clinical Journal of the American Society of Nephrology Clin J Am Soc Nephrol 1: , 2006 Figure 1. Vascular access during 1-yr follow-up period (N 418). rate of a vascular catheter, 1.23 per person-year, was more than double that for a permanent access, 0.54 per person-year. Adjustment for age, gender, race, dialysis vintage, hemoglobin, and albumin (Table 3) provided relative risk estimates that were similar to the crude rate ratios. Sensitivity analyses that were based on the algorithm described did not significantly change the point estimates or CI. For example, the population designated as having complete Medicare coverage during the follow-up period (n 366) had the following relative risks (95% CI), comparing vascular catheters with a permanent access: All-cause hospitalization 1.88 (1.39 to 2.56), infection-related hospitalization 5.50 (2.21 to 13.72), and; complication of access 2.94 (2.13 to 4.05). Discussion Caregivers of pediatric patients who receive hemodialysis likely concur that providing dialysis access to the pediatric population is a time-consuming and frustrating challenge (22). The complication and hospitalization rates that are associated with vascular access and that were observed in this analysis support this statement. This challenge is compounded by the fact that decisions related to the placement and management of vascular access in children carry a lifelong impact. The high rate of renal transplantation in children supports the modus operandi that dialysis is a bridge to transplantation. However, with current management, the vast majority of these children ultimately will return to dialysis at least once in their lifetime. Analysis of United Network for Organ Sharing data from 1987 to 1996 projected graft half-lives of 7 yr for the adolescent age group (13 to 21 yr of age), 11 yr for children (3 to 12 yr of age), and 18 yr in those who are younger than 2 yr (29,30). Data regarding outcomes in the pediatric population exist but have been sparse. Regarding access longevity, Lumsden et al. (22) retrospectively examined hemodialysis access in 24 children. Of 15 AVF, one third failed to mature, and the mean functional patency was mo. Of 21 AVG (polytetrafluoroethylene), the mean functional patency was mo; thrombectomy was performed in 25 cases; and eight graft infections occurred, seven of which resulted in graft loss. Gradman et al. (21) examined 47 consecutive children (mean age 14.6 yr) in whom AVF were constructed. Primary patency at 1 and 2 yr was 100 and 96%, respectively. Three accesses had thromboses, and of these, two were salvaged. No infections were reported. Brittinger et al. (20) reported 20 yr of experience with various types of AVF and AVG in all age groups. Complicationfree functioning of AVF after 12 mo ranged from 57 to 100% for the various age groups and fistula types and from 50 to 100% for AVG. Sheth et al. (24) examined the survival of permanent vascular access in 34 pediatric patients with ESRD. Of 24 AVF, eight (33%) had primary failure. Of the functioning AVF, the 1- and 3-yr patency rates were 74 and 59%, respectively. Of 28 AVG, the 1- and 3-yr patency rates were 96 and 69%, respectively. Thrombosis, stenosis, and infection occurred significantly more frequently in AVG. A 20-yr retrospective study was performed by Ramage et al. (23) A total of 304 access procedures were performed on 114 pediatric patients. Primary failure occurred in 25 of 107 AVF placed. Considering only first-access procedures, the median survival of AVF was 3.1 yr. Of the 182 vascular catheters, the median survival was 0.6 yr. Of possible complications, infections led to access loss in 30% of those with a catheter and 3% of those with an AVF, and thrombosis led to access loss in 54% of those with catheter and 71% of those with AVF. Microsurgical techniques for the placement of AVG and AVF have resulted in improved long-term access survival. Patent and functional AVF in 60% of pediatric patients have been reported at 4 yr of follow-up (31 34). Goldstein et al. (26) examined the survival of 22 cuffed catheters. The 1-yr survival was 27%, with infection and kinking being the most common reasons for removal. Finally, to examine the clinical outcomes of urea clearance, anemia, and serum albumin concentration, Chand et al. (25) prospectively followed 140 pediatric patients during a 2-yr period. A trend toward better urea clearance, higher hemoglobin, and higher albumin was observed in patients with a permanent access compared with those with a catheter. In this study, having a vascular catheter for hemodialysis access was independently associated with an almost two-fold increase in hospitalization, an almost five-fold increase in hospitalization as a result of infection, and an almost three-fold increase in complications of access. Patients with vascular catheters also were more likely to have lower hemoglobin, serum albumin, and spkt/v values. Although this study examines the largest cohort of pediatric hemodialysis patients assembled, it has limitations. USRDS data are generated from administrative billing data; therefore, the possibility of misclassification exists for hospitalizations and procedures by access type. This misclassification bias, however, likely would bias toward a lower estimate of risk than reported. The collapse of the AVF and AVG access categories into the single permanent access category limits comparison of these two groups. However, preliminary analysis of these data found that as compared with AVF, there was not an increased risk for infection-related hospitalization in patients with an AVG (odds ratio 1.2; 95% CI 0.3 to 3.9). In the same analysis, patients with a vascular catheter were 4.5 times more likely to have an infection-related hospitalization as compared with those with an AVF. Pediatric-specific issues related to vascular access must be acknowledged. Patient body size and the availability of vascular surgeons who are skilled and willing to create such accesses in the pediatric population limit options in particular cases.

5 Clin J Am Soc Nephrol 1: , 2006 Vascular Access Outcomes in Adolescents 991 Table 2. Crude incidence rates and rate ratios for outcomes associated with vascular access type in adolescent patients who receive hemodialysis a Outcome Catheter Permanent Access Rate Ratio b 95% CI Hospitalization, all-cause to 2.15 Hospitalization, infection-related to Access complication to 2.90 a Denominator: Person-years. CI, confidence interval. b Comparing catheter to permanent access. Table 3. RR (catheter versus permanent access) of dialysis outcomes in adolescent patients who received hemodialysis a Parameter Hospitalization, All-Cause Hospitalization, Infection-Related Access Complication RR b 95% CI RR 95% CI RR 95% CI Vascular catheter versus permanent access 1.84 d 1.38 to d 2.02 to d 2.00 to 3.69 Age, per year to to to 1.20 Male versus female to to d 1.04 to 2.05 Black versus nonblack to to to 1.76 Dialysis vintage, 6 versus 6 mo to to d 1.11 to 2.35 Mean hemoglobin 11 versus 11 g/dl to to to 1.20 Mean serum albumin 3.5/3.2 versus 3.5/3.2 g/dl c to to to 1.88 a Relative risks (RR) and CI were obtained from general estimating equation regression modeling. b Adjusted for all other variables in table. c Bromcresol green/bromcresol purple laboratory method. d P However, as has been proved in the adult population with ESRD, AVF are associated with less morbidity in the pediatric population. It is likely that most pediatric nephrologists have already extrapolated evidence regarding improved clinical outcomes that are associated with AVF in the adult ESRD population to the pediatric population, yet vascular catheters continue to be the predominant form of vascular access, and there is no evidence that catheter use has decreased during at least the past 5 yr. Future study needs to place emphasis on the barriers to the creation and maintenance of AVF in the pediatric hemodialysis population. With this information, pediatric-specific vascular access guidelines can be formulated so that pediatric nephrologists will be well informed about their current vascular access choices, and their patients will be well positioned for a lifetime of managing chronic kidney disease. Acknowledgments This work was supported by National Institutes of Health grant R21-DK to S.L.F. J.J.F. was supported by the American Kidney Fund Clinical Scientist in Nephrology Program. Portions of these data were presented in abstract form at the annual meeting of the American Society of Nephrology; October 29 through November 1, 2004; St. Louis, MO; and the Pediatric Academic Society Meeting, May 14 to 17, 2005; Washington, DC. The data reported here were supplied by the Centers for Medicare & Medicaid Services ESRD Clinical Performance Measures Project and the USRDS. We thank Marjorie R. Bedinger, BA, for assistance in creating the data file for analysis. References 1. Astor BC, Eustace JA, Powe NR, Klag MJ, Fink NE, Coresh J: Type of vascular access and survival among incident hemodialysis patients: The Choices for Healthy Outcomes in Caring for ESRD (CHOICE) Study. J Am Soc Nephrol 16: , Albers FJ: Causes of hemodialysis access failure. Adv Ren Replace Ther 1: , Caruana RJ, Raja RM, Zeit RM, Goldstein SJ, Kramer MS: Thrombotic complications of indwelling central catheters used for chronic hemodialysis. Am J Kidney Dis 9: , Churchill DN, Taylor DW, Cook RJ, LaPlante P, Barre P, Cartier P, Fay WP, Goldstein MB, Jindal K, Mandin H, et al.: Canadian Hemodialysis Morbidity Study. Am J Kidney Dis 19: , Dhingra RK, Young EW, Hulbert-Shearon TE, Leavey SF, Port FK: Type of vascular access and mortality in US hemodialysis patients. Kidney Int 60: , Harland RC: Placement of permanent vascular access de-

6 992 Clinical Journal of the American Society of Nephrology Clin J Am Soc Nephrol 1: , 2006 vices: Surgical considerations. Adv Ren Replace Ther 1: , Hoen B, Paul-Dauphin A, Hestin D, Kessler M: EPIBAC- DIAL: A multicenter prospective study of risk factors for bacteremia in chronic hemodialysis patients. J Am Soc Nephrol 9: , Kairaitis LK, Gottlieb T: Outcome and complications of temporary haemodialysis catheters. Nephrol Dial Transplant 14: , Kherlakian GM, Roedersheimer LR, Arbaugh JJ, Newmark KJ, King LR: Comparison of autogenous fistula versus expanded polytetrafluoroethylene graft fistula for angioaccess in hemodialysis. Am J Surg 152: , Munda R, First MR, Alexander JW, Linnemann CC Jr, Fidler JP, Kittur D: Polytetrafluoroethylene graft survival in hemodialysis. JAMA 249: , Palder SB, Kirkman RL, Whittemore AD, Hakim RM, Lazarus JM, Tilney NL: Vascular access for hemodialysis. Patency rates and results of revision. Ann Surg 202: , Pastan S, Soucie JM, McClellan WM: Vascular access and increased risk of death among hemodialysis patients. Kidney Int 62: , Powe NR, Jaar B, Furth SL, Hermann J, Briggs W: Septicemia in dialysis patients: Incidence, risk factors, and prognosis. Kidney Int 55: , Tokars JI, Miller ER, Stein G: New national surveillance system for hemodialysis-associated infections: Initial results. Am J Infect Control 30: , Centers for Medicare & Medicaid Services: Fistula First. National Vascular Access Improvement Initiative. Available: Accessed December 13, National Kidney Foundation: K/DOQI clinical practice guidelines for vascular access, Am J Kidney Dis 37: , United States Renal Data System: USRDS 2005 Annual Data Report: Atlas of End-Stage Renal Disease in the United States, Bethesda, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Centers for Medicare & Medicaid Services: 2004 Annual Report, End Stage Renal Disease Clinical Performance Measures Project, Baltimore, Department of Health and Human Services, Centers for Medicare & Medicaid Services, Office of Clinical Standards & Quality, December Frankenfield DL, Neu AM, Warady BA, Watkins SL, Friedman AL, Fivush BA: Adolescent hemodialysis: Results of the 2000 ESRD Clinical Performance Measures Project. Pediatr Nephrol 17: 10 15, Brittinger WD, Walker G, Twittenhoff WD, Konrad N: Vascular access for hemodialysis in children. Pediatr Nephrol 11: 87 95, Gradman WS, Lerner G, Mentser M, Rodriguez H, Kamil ES: Experience with autogenous arteriovenous access for hemodialysis in children and adolescents. Ann Vasc Surg 19: , Lumsden AB, MacDonald MJ, Allen RC, Dodson TF: Hemodialysis access in the pediatric patient population. Am J Surg 168: , Ramage IJ, Bailie A, Tyerman KS, McColl JH, Pollard SG, Fitzpatrick MM: Vascular access survival in children and young adults receiving long-term hemodialysis. Am J Kidney Dis 45: , Sheth RD, Brandt ML, Brewer ED, Nuchtern JG, Kale AS, Goldstein SL: Permanent hemodialysis vascular access survival in children and adolescents with end-stage renal disease. Kidney Int 62: , Chand DH, Brier M, Strife CF: Comparison of vascular access type in pediatric hemodialysis patients with respect to urea clearance, anemia management, and serum albumin concentration. Am J Kidney Dis 45: , Goldstein SL, Macierowski CT, Jabs K: Hemodialysis catheter survival and complications in children and adolescents. Pediatr Nephrol 11: 74 77, Verrina E, Edefonti A, Gianoglio B, Rinaldi S, Sorino P, Zacchello G, Lavoratti G, Maringhini S, Pecoraro C, Calevo MG, Turrini Dertenois L, Perfumo F: A multicenter experience on patient and technique survival in children on chronic dialysis. Pediatr Nephrol 19: 82 90, Frankenfield DL, Neu AM, Warady BA, Fivush BA, Johnson CA, Brem AS: Anemia in pediatric hemodialysis patients: Results from the 2001 ESRD Clinical Performance Measures Project. Kidney Int 64: , Smith JM, McDonald RA: Renal transplantation in adolescents. Adolesc Med Clin 16: , Cecka JM, Gjertson DW, Terasaki PI: Pediatric renal transplantation: A review of the UNOS data. United Network for Organ Sharing. Pediatr Transplant 1: 55 64, Bagolan P, Spagnoli A, Ciprandi G, Picca S, Leozappa G, Nahom A, Trucchi A, Rizzoni G, Fabbrini G: A ten-year experience of Brescia-Cimino arteriovenous fistula in children: Technical evolution and refinements. J Vasc Surg 27: , Bourquelot P, Cussenot O, Corbi P, Pillion G, Gagnadoux MF, Bensman A, Loirat C, Broyer M: Microsurgical creation and follow-up of arteriovenous fistulae for chronic haemodialysis in children. Pediatr Nephrol 4: , Bourquelot P, Raynaud F, Pirozzi N: Microsurgery in children for creation of arteriovenous fistulas in renal and non-renal diseases. Ther Apher Dial 7: , Sanabia J, Polo JR, Morales MD, Canals MJ, Polo J, Serantes A: Microsurgery in gaining paediatric vascular access for haemodialysis. Microsurgery 14: , 1993