Canadian Hemodialysis Morbidity Study

Retrospective review of arteriovenous fistula success rate in a multi-ethnic Asian population

BACKGROUND

Native vein arteriovenous fistulas (AVFs) are the recommended first-line vascular access in hemodialysis patients. Despite this, AVFs are plagued with unfavorable maturation rates. We conducted a retrospective cohort study to assess the AVF success rate and to identify any significant associating factors.

METHODOLOGY

Demographic and clinical data of all AVFs created from January 2011 to June 2013 at a single center with a multi-ethnic Asian population, were reviewed. The primary outcome was AVF successfully used for hemodialysis (FUSH) at 6 months. Secondary endpoints were the overall FUSH and actual maturation time of the AVFs. Univariate and multivariate analyses were performed to identify factors associated with AVF success.

RESULTS

A total of 375 fistulas were created during the study period (110 radiocephalic, 176 brachiocephalic, 89 brachiobasilic). The mean age was 59.4 ± 12.6 years and 42.9% were females. Seventy-one percent of patients had diabetes, 32.5% had ischemic heart disease and 10.7% had peripheral vascular disease. 246/375 (65.6%) AVFs FUSH by 6 months, and the average AVF maturation time was 16.1 ± 10.7 weeks. Of the 246 AVFs, 11% required secondary procedure to assist their success. Univariate analysis showed that gender (p = 0.035), age (p = 0.018), vein size on pre-operative vein mapping (p = 0.004) and operating surgeon (p = 0.021) were significant factors associated with AVF success. On multivariate analysis, age, pre-operative vein size and operating surgeon were significantly associated with fistula success.

CONCLUSIONS

Reasonable FUSH rates can be achieved in the study patients. Patient age, pre-operative vein mapping size and operating surgeon were shown to influence AVF success rate.

Differences in Initial Hemodialysis Vascular Access Use Among Glomerulonephritis Subtypes in the United States

BACKGROUND

The type of vascular access used for hemodialysis affects patient morbidity and mortality. Whether vascular access types differ by glomerulonephritis (GN) subtype in the US hemodialysis population has not been investigated.

STUDY DESIGN

Cross-sectional observational study.

SETTING & PARTICIPANTS

We identified all adult (aged ≥ 18 years) patients within the US Renal Data System who initiated hemodialysis therapy from July 2005 through December 2011 with a diagnosis of end-stage renal disease attributed to any of 4 primary (focal segmental glomerulosclerosis, immunoglobulin A nephropathy [reference group], membranous nephropathy, and membranoproliferative GN) or 2 secondary (lupus nephritis and vasculitis) GN subtypes.

PREDICTOR

GN subtype.

OUTCOMES

ORs with 95% CIs for arteriovenous fistula versus central venous catheter (CVC) use and for arteriovenous graft versus CVC use were computed using multinomial logistic regression, with adjustment for demographic, socioeconomic, comorbidity, and duration of nephrology care covariates.

RESULTS

Among 29,015 patients, CVC use at initiation of hemodialysis therapy was substantially higher in patients with lupus nephritis (89.2%) or vasculitis (91.2%) compared with patients with primary GN subtypes (72.7%-79.8%). After adjustment and compared with patients with immunoglobulin A nephropathy, patients with lupus nephritis or vasculitis were as likely to have used an arteriovenous graft (ORs of 0.94 [95% CI, 0.70-1.27] and 0.80 [95% CI, 0.56-1.13], respectively) but significantly less likely to have used an arteriovenous fistula (ORs of 0.66 [95% CI, 0.57-0.76] and 0.54 [95% CI, 0.45-0.63], respectively), whereas patients with any comparator primary GN subtype were at least as likely to have used either of these 2 access types.

LIMITATIONS

Potential misclassification of exposure; residual confounding by unmeasured covariates; inability to determine causes of observed associations; lacking longitudinal data for vascular access use.

CONCLUSIONS

Significant differences in vascular access distributions at initiation of hemodialysis therapy are apparent among GN subtypes. The unacceptably high use of CVCs in patients with lupus nephritis and vasculitis is particularly concerning. Further studies are needed to identify any potentially modifiable factors underlying these findings.

Pre-Access Creation Evaluation--Is Vein Mapping Enough?

The changing demographic of the hemodialysis population in the United States is posing significant challenge for selection and creation of an optimal vascular access. An arteriovenous fistula (AVF) is by far the most reliable access provided it matures and functions successfully. System-wide changes implemented by Fistula First Breakthrough Initiative and Kidney Disease Outcomes Quality Initiative guidelines have increased the awareness and incidence of AVF in the prevalent dialysis population; however, achieving the current goal of 68% AVF rate continues to remain elusive. The present article reviews the evidence in literature in support of and against using vessel mapping alone as a strategy to improve AVF rate. The current strategy of evaluating the vessels before an access is created seems to be inadequate. A patient-centered approach for an optimal vascular access needs to be considered to improve the AVF rate.

Preoperative vascular access evaluation for haemodialysis patients

BACKGROUND

Haemodialysis treatment requires reliable vascular access. Optimal access is provided via functional arteriovenous fistula (fistula), which compared with other forms of vascular access, provides superior long-term patency, requires few interventions, has low thrombosis and infection rates and cost. However, it has been estimated that between 20% and 60% of fistulas never mature sufficiently to enable haemodialysis treatment. Mapping blood vessels using imaging technologies before surgery may identify vessels that are most suitable for fistula creation.

OBJECTIVES

We compared the effect of conducting routine radiological imaging evaluation for vascular access creation preoperatively with standard care without routine preoperative vessel imaging on fistula creation and use.

SEARCH METHODS

We searched Cochrane Kidney and Transplant's Specialised Register to 14 April 2015 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that enrolled adult participants (aged ≥ 18 years) with chronic or end-stage kidney disease (ESKD) who needed fistulas (both before dialysis and after dialysis initiation) that compared fistula maturation rates relating to use of imaging technologies to map blood vessels before fistula surgery with standard care (no imaging).

DATA COLLECTION AND ANALYSIS

Two authors assessed study quality and extracted data. Dichotomous outcomes, including fistula creation, maturation and need for catheters at dialysis initiation, were expressed as risk ratios (RR) with 95% confidence intervals (CI). Continuous outcomes, such as numbers of interventions required to maintain patency, were expressed as mean differences (MD). We used the random-effects model to measure mean effects.

MAIN RESULTS

Four studies enrolling 450 participants met our inclusion criteria. Overall risk of bias was judged to be low in one study, unclear in two, and high in one.There was no significant differences in the number of fistulas that were successfully created (4 studies, 433 patients: RR 1.06, 95% CI 0.95 to 1.28; I² = 76%); the number of fistulas that matured at six months (3 studies, 356 participants: RR 1.11, 95% CI 0.98 to 1.25; I² = 0%); number of fistulas that were used successfully for dialysis (2 studies, 286 participants: RR 1.12, 95% CI 0.99 to 1.28; I² = 0%); the number of patients initiating dialysis with a catheter (1 study, 214 patients: RR 0.66, 95% CI 0.42 to 1.04); and in the rate of interventions required to maintain patency (1 study, 70 patients: MD 14.70 interventions/1000 patient-days, 95% CI -7.51 to 36.91) between the use of preoperative imaging technologies compared with standard care (no imaging).

AUTHORS' CONCLUSIONS

Based on four small studies, preoperative vessel imaging did not improve fistula outcomes compared with standard care. Adequately powered prospective studies are required to fully answer this question.

Risk factors for in-hospital mortality in patients starting hemodialysis

BACKGROUND

Incident hemodialysis patients have the highest mortality in the first several months after starting dialysis. This study evaluated the in-hospital mortality rate after hemodialysis initiation, as well as related risk factors.

METHODS

We examined in-hospital mortality and related factors in 2,692 patients starting incident hemodialysis. The study population included patients with acute kidney injury, acute exacerbation of chronic kidney disease, and chronic kidney disease. To determine the parameters associated with in-hospital mortality, patients who died in hospital (nonsurvivors) were compared with those who survived (survivors). Risk factors for in-hospital mortality were determined using logistic regression analysis.

RESULTS

Among all patients, 451 (16.8%) died during hospitalization. The highest risk factor for in-hospital mortality was cardiopulmonary resuscitation, followed by pneumonia, arrhythmia, hematologic malignancy, and acute kidney injury after bleeding. Albumin was not a risk factor for in-hospital mortality, whereas C-reactive protein was a risk factor. The use of vancomycin, inotropes, and a ventilator was associated with mortality, whereas elective hemodialysis with chronic kidney disease and statin use were associated with survival. The use of continuous renal replacement therapy was not associated with in-hospital mortality.

CONCLUSION

Incident hemodialysis patients had high in-hospital mortality. Cardiopulmonary resuscitation, infections such as pneumonia, and the use of inotropes and a ventilator was strong risk factors for in-hospital mortality. However, elective hemodialysis for chronic kidney disease was associated with survival.

Risk of Stroke in Patients with ESRD

BACKGROUND AND OBJECTIVES

This study aimed to determine absolute and excess stroke risks in people with ESRD compared with the general population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This cohort study used data linkage between the Australia and New Zealand Dialysis and Transplant Registry and hospital and death records for 10,745 people with ESRD in New South Wales from 2000 to 2010. For the general population, Australian Institute of Health and Welfare hospital usage records and Australian Bureau of Statistics census data were used. Rates and standardized incidence rate ratios of hospitalization with a stroke were calculated.

RESULTS

People with ESRD had 640 hospitalizations with stroke in 49,472 person-years of follow-up (1294 per 100,000 person-years), and people in the general population had 338,392 hospitalizations with stroke (212 per 100,000 person-years), an incidence rate ratio of 3.32 (95% confidence interval, 3.31 to 3.33). Excess risk was greater for women (incidence rate ratio, 5.14; 95% confidence interval, 5.11 to 5.18) than men (incidence rate ratio, 2.52; 95% confidence interval, 2.51 to 2.54; P for interaction <0.001) and decreased with age. People ages 35-39 years old with ESRD had an 11 times increased risk of stroke (incidence rate ratio, 11.08; 95% confidence interval, 9.41 to 13.05), and risk in people ages ≥85 years old increased 2-fold (incidence rate ratio, 2.04; 95% confidence interval, 1.87 to 2.23; P for interaction <0.001). Excess risk was greater for intracerebral hemorrhage (incidence rate ratio, 4.18; 95% confidence interval, 4.11 to 4.26) than ischemic stroke (incidence rate ratio, 3.43; 95% confidence interval, 3.40 to 3.45; P for interaction <0.01).

CONCLUSIONS

People with ESRD have a substantially higher risk of stroke, particularly women and young people, and hemorrhagic stroke. Future work could investigate effective and safe interventions for primary and secondary prevention of stroke in people with ESRD.

Medical adjuvant treatment to increase patency of arteriovenous fistulae and grafts

BACKGROUND

End-stage renal disease (ESRD) patients often require either the formation of an arteriovenous (AV) fistula or an AV interposition prosthetic shunt for haemodialysis. These access sites should ideally have a long life and a low rate of complications (for example thrombosis, infection, stenosis, aneurysm formation and distal limb ischaemia). Although some of the complications may be unavoidable, any adjuvant technique or medical treatment aimed at decreasing complications would be welcome. This is the second update of the review first published in 2004.

OBJECTIVES

To assess the effects of adjuvant drug treatment in ESRD patients on haemodialysis via autologous AV fistulae or prosthetic interposition AV shunts.

SEARCH METHODS

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched March 2015) and CENTRAL (2015, Issue 2).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of active drug versus placebo in people with ESRD undergoing haemodialysis via an AV fistula or prosthetic interposition AV graft.

DATA COLLECTION AND ANALYSIS

For this update, the two review authors (NCT, ADS) independently assessed trial quality and one review author (NCT) extracted data. Information on adverse events was collected from the trials. The primary outcome was the long-term fistula or graft patency rate. Secondary outcomes included duration of hospital stay, complications and number of related surgical interventions.

MAIN RESULTS

For this update, an additional six studies were deemed suitable for inclusion, making a total of 15 trials with 2230 participants. Overall the quality of the evidence was low due to short follow-up periods, heterogeneity between trials and moderate methodological quality of the studies due to incomplete reporting. Medical adjuvant treatments used in the trials were aspirin, ticlopidine, dipyridamole, dipyridamole plus aspirin, warfarin, fish oil, clopidogrel, sulphinpyrazone, and human type I pancreatic elastase (PRT-201). Where possible, the included studies were pooled into similar medical adjuvant groups for meta-analyses.All included studies reported on graft patency by measuring graft thrombosis. There was insufficient evidence to determine if there was a difference in graft patency in studies comparing aspirin versus placebo (three RCTs, 175 participants) (odds ratio (OR) 0.40, 95% confidence interval (CI) 0.07 to 2.25; P = 0.30). The meta-analysis for graft patency comparing ticlopidine versus placebo (three RCTs, 339 participants) favoured ticlopidine (OR 0.45, 95% CI 0.25 to 0.82; P = 0.009). There was insufficient evidence to determine if there was a difference in graft patency in studies comparing fish oil versus placebo (two RCTs, 220 participants; OR 0.24, 95% CI 0.03 to 1.95; P = 0.18); and studies comparing clopidogrel and placebo (two RCTs, 959 participants; OR 0.40, 95% CI 0.13 to 1.19; P = 0.10). Similarly, there was insufficient evidence to determine if there was a difference in graft patency in three studies (306 participants) comparing PRT-201 versus placebo (OR 0.75, 95% CI 0.42 to 1.32; P = 0.31); in one trial comparing the effect of dipyridamole versus placebo (42 participants; OR 0.46, 95% CI 0.11 to 1.94, P = 0.29) and dipyridamole plus aspirin versus placebo (41 participants; OR 0.64, CI 0.16 to 2.56, P = 0.52); in one trial comparing low-dose warfarin with placebo (107 participants; OR 1.76, 95% CI 0.78 to 3.99, P = 0.17); and one trial (16 participants) comparing sulphinpyrazone versus placebo (OR 0.43, 95% CI 0.03 to 5.98, P = 0.53). The single trial evaluating warfarin was terminated early because of major bleeding events in the warfarin group. Only two studies published data on the secondary outcome of related interventions (surgical or radiological); there was insufficient evidence to determine if there was a difference in related interventions between placebo and treatment groups. No studies reported on the length of hospital stay and data reporting on complications was limited and varied between studies.

AUTHORS' CONCLUSIONS

The meta-analyses of three studies for ticlopidine (an anti-platelet treatment), which all used the same dose of treatment but with a short follow-up of only one month, suggest ticlopidine may have a beneficial effect as an adjuvant treatment to increase the patency of AV fistulae and grafts in the short term. There was insufficient evidence to determine if there was a difference in graft patency between placebo and other treatments such as aspirin, fish oil, clopidogrel, PRT-201, dipyridamole, dipyridamole plus aspirin, warfarin, and sulphinpyrazone. However, the quality of the evidence was low due to short follow-up periods, the small number of studies for each comparison, heterogeneity between trials and moderate methodological quality of the studies due to incomplete reporting. It, therefore, appears reasonable to suggest further prospective studies be undertaken to assess the use of these anti-platelet drugs in renal patients with an arteriovenous fistula or graft.

Risk and Prognosis of Bloodstream Infections among Patients on Chronic Hemodialysis: A Population-Based Cohort Study

Background and Objectives

Infections are common complications among patients on chronic hemodialysis. This population-based cohort study aims to estimate risk and case fatality of bloodstream infection among chronic hemodialysis patients.

Methods

In this population-based cohort study we identified residents with end-stage renal disease in Central and North Jutland, Denmark who had hemodialysis as first renal replacement therapy (hemodialysis patients) during 1995–2010. For each hemodialysis patient, we sampled 19 persons from the general population matched on age, gender, and municipality. Information on positive blood cultures was obtained from regional microbiology databases. All persons were observed from cohort entry until first episode of bloodstream infection, emigration, death, or end of hemodialysis treatment, whichever came first. Incidence-rates and incidence-rate ratios were computed and risk factors for bloodstream infection assessed by Poisson regression. Case fatality was compared by Cox regression.

Results

Among 1792 hemodialysis patients and 33 618 matched population controls, we identified 461 and 1126 first episodes of bloodstream infection, respectively. Incidence rates of first episode of bloodstream infection were 13.7 (95% confidence interval (CI), 12.5–15.0) per 100 person-years among hemodialysis patients and 0.53 (95% CI, 0.50–0.56) per 100 person-years among population controls. In hemodialysis patients, the most common causative microorganisms were Staphylococcus aureus (43.8%) and Escherichia coli (12.6%). The 30-day case fatality was similar among hemodialysis patients and population controls 16% (95% CI, 13%–20%) vs. 18% (95% CI, 15%–20%).

Conclusions

Hemodialysis patients have extraordinary high risk of bloodstream infection while short-term case fatality following is similar to that of population controls.

An Outbreak of Methicillin-ResistantStaphylococcus aureusInfections Related to Central Venous Catheters for Hemodialysis

Objectives:

To determine risk factors for hemodialysis catheter-related bloodstream infections (HCRBSIs) and investigate whether use of maximal sterile barrier precautions would prevent HCRBSIs.

Setting:

Tertiary-care medical center hemodialysis unit.

Design:

Open trial with historical comparison and case-control study of risk factors for HCRBSIs.

Methods:

Prospective surveillance was used to compare HCRBSI rates for 1 year before and after implementation of maximal sterile barrier precautions. A case–control study compared 50 case-patients with HCRBSI with 51 randomly selected control-patients.

Results:

The HCRBSI rate was 1.6% per 100 dialysis runs (CI95, 1.1%–2.3%) in the first year and 0.77% (CI95, 0.5%–1.1%) in the second year (P= .0106). The most frequent cause of HCRBSI was MRSA in the first year (15 of 32) and MSSA in the second year (13 of 18). Ten MRSA blood isolates in the first year were identical by PFGE. Diabetes mellitus was a risk factor for HCRBSI. Age, gender, site of hemodialysis central venous catheter (CVC), other underlying diseases, coma score, APACHE II score, serum albumin level, and cholesterol level were not associated with HCRBSI and did not change between the 2 years. Hospital stay was prolonged for case-patients (32.78 ± 20.96 days) versus control-patients (22.75 ± 17.33 days), but mortality did not differ.

Conclusions:

Use of maximal sterile barrier precautions during the insertion of CVCs reduced HCRBSIs in dialysis patients and seemed cost-effective. Diabetes mellitus was associated with HCRBSI. An outbreak of MRSA in the first year was likely caused by cross-infection via medical personnel.

Differences in coagulation in clotting of vascular access in hemodialysis patients

Arteriovenous graft (AVG) thrombosis is a frequent cause of graft failure. We evaluated coagulation protein concentrations, platelet function, and viscoelasticity factors in 20 hemodialysis (HD) patients with AVGs. The goal was to determine whether significant differences in protein concentrations, platelet function, and viscoelasticity factors exist among dialysis patients requiring frequent AVG declot procedures vs. those who do not. Twenty HD patients were enrolled: 10 frequent clotters (>3 declots in the previous year) and 10 were nonclotters. Patients on antiplatelets or chronic anticoagulation were excluded. Laboratories were drawn pretreatment and heparinase was added to counteract any potential heparin effect. Coagulation protein concentrations including tissue factor (TF), thrombin/antithrombin III complex (TAT), and prothrombin fragment 1 + 2 (F(1+2)) were assayed. The time to clot onset was measured by force onset time (FOT). Platelet contractile force (PCF) measured the force produced by platelets during clot retraction, whereas clot rigidity was measured as clot elastic modulus (CEM). FOT, CEM, and PCF were measured by Hemodyne. Both groups had upregulation of the TF pathway, as TF, TAT, and F(1+2) levels were similarly increased over baseline levels. Hemodialysis patients with frequent AVG clotting had higher levels of both PCF and CEM compared with nonclotters. Additionally, the frequent clotters had a lower FOT relative to nonclotters, although both were considered in the normal range. Our study suggests that HD patients with recurrent AVG thrombotic events form clots with higher tensile strength compared with HD patients without recurrent graft thrombosis.

Comparison of Flixene™ and Standard PTFE Arteriovenous Graft for Early Haemodialysis

Purpose

The purpose is to compare the outcomes of FLIXENE™ arteriovenous graft (AVG) to standard polytetrafluoroethylene (PTFE) AVG for early haemodialysis.

Methods

This is a prospective observational study of all AVGs placed over a 40-month period between 2008 and 2011 at our vascular unit. Primary outcome was to examine early cannulation rates for FLIXENE™. Secondary outcomes included patency rates, usability of grafts, complications in particular infections, interventions and death in comparison to standard PTFE grafts.

Results

Forty-five FLIXENE™ and 19 standard PTFE AVGs were placed in the study period; 89% of FLIXENE™ grafts were used for dialysis, with 78% cannulated within 3 days. At 18 months, primary patency (FLIXENE™ 34% vs standard PTFE 24%), primary assisted patency (35% vs 36%) and secondary patency rate (51% vs 48%) were not statistically different; 20.2% of FLIXENE™ grafts were infected at 18 months requiring explantation compared with 40.3% of standard PTFE grafts (p=0.14).

Conclusions

FLIXENE™ can be cannulated for dialysis within 3 days. It has similar patency and complication rates as other prosthetic grafts in the market. In patients who have no access and require urgent dialysis, FLIXENE™ is a viable option.

Vascular access type, inflammatory markers, and mortality in incident hemodialysis patients: the Choices for Healthy Outcomes in Caring for End-Stage Renal Disease (CHOICE) Study

BACKGROUND

Few reports have shown an association between access type and inflammatory marker levels in a longitudinal cohort. We investigated the role of access type on serial levels of inflammatory markers and the role of inflammatory markers in mediating the association of access type and risk of mortality in a prospective study of incident dialysis patients.

STUDY DESIGN

Cohort study, post hoc analysis of the CHOICE (Choices for Healthy Outcomes in Caring for ESRD) Study.

SETTING & PARTICIPANTS

In 583 participants, inflammation was assessed by measuring serum C-reactive protein (CRP) and interleukin 6 (IL-6) after access placement and at multiple times during 3 years' follow-up. Type of access was categorized as central venous catheter (CVC), arteriovenous graft (AVG), and arteriovenous fistula (AVF), and changes over time were recorded.

PREDICTOR

Access type, age, sex, race, body mass index, diabetes, cardiovascular disease, and serum albumin level.

OUTCOMES

CRP level, IL-6 level, and mortality.

MEASUREMENTS

We used mixed-effects pattern mixture models to study the association between access type and repeated measurements of inflammation and survival analysis to investigate the association of access type and mortality, adjusting for predictors.

RESULTS

In a mixed-effects pattern mixture model, compared with AVFs, the presence of CVCs and AVGs was associated with 62% (P=0.02) and 30% (P=0.05) increases in average CRP levels, respectively. A Cox proportional hazards model yielded nonsignificant associations of CVC and AVG use (vs AVFs) with risk of mortality when adjusted for inflammatory marker levels. Higher CRP levels were associated with increased risk of CVC failure than lower CRP levels.

LIMITATIONS

CRP and IL-6 measurements not performed for all hemodialysis patients.

CONCLUSIONS

CVCs, compared with AVFs, are associated with a greater state of inflammation in incident hemodialysis patients, and the association of catheter use and mortality may be mediated by access-induced inflammation. Our findings support recommendations for the early removal or avoidance of CVC placements.

Evaluating and treating venous outflow stenoses is necessary for the successful open surgical treatment of arteriovenous fistula aneurysms

BACKGROUND

Arteriovenous fistula (AVF) aneurysms (AVFAs) can lead to skin erosion, bleeding, difficult access while on hemodialysis, and poor cosmetic appearance. We reviewed our experience in treating patients with aneurysmal dilatation of their AVF.

METHODS

We reviewed clinical data of 48 patients (37 men; overall mean age, 55 years; range, 28-85 years) with an AVFA who underwent treatment during a 30-month period. Relevant clinical variables and treatment outcomes were analyzed.

RESULTS

All patients underwent a fistulogram, and 90% required percutaneous angioplasty to improve outflow. Fifty-six percent of patients had one stenotic outflow lesion, and 44% had at least two tandem outflow stenoses that required treatment. Open repair with aneurysmorrhaphy was performed in one stage in 64% of patients and in two stages in 36%. A tunneled hemodialysis catheter was required in 11 patients (23%) until the surgically repaired AVF was ready for use again, comprising 10 patients treated with single-stage surgery and only one patient in the staged group. All AVFAs were effectively treated, and patients were able to maintain functional use of their access when healed.

CONCLUSIONS

There is a high association of venous outflow stenoses and AVFA. Comprehensive therapy should encompass treatment of any venous outflow stenoses before open AVFA repair. A two-stage repair may decrease tunneled hemodialysis catheter use in patients with multiple aneurysms.

Initial Experience with the Gore® Acuseal Graft for Prosthetic Vascular Access

Purpose

The purpose of this study is to report the short-term results of the Gore® Acuseal graft for prosthetic vascular access (pVA) in patients with end-stage renal disease on hemodialysis.

Methods

Between October 2011 and October 2013, all the consecutive patients who underwent implantation of a new expanded Polytetrafluoroethylene (ePTFE) tri-layer graft were included in the study. Primary and secondary patency rate, time to first cannulation, and complications were recorded. Follow-up was performed at 1, 3, 6, and 12 months after the intervention.

Results

Thirty ePTFE tri-layer heparin bonded grafts were implanted in 18 males and 12 females. The graft configuration was radial-basilic (n=12, 40%), brachial-basilic (n=10, 33.3%), femoro-femoral (n=3, 10.0%), radial-cephalic (n=2, 6.7%), radial-antecubital forearm (n=2, 6.7%), and brachial-axillary (n=1, 3.3%). No patient was lost during a mean follow-up time of 6.3±5.9 months (range, 1-24; median, 5). Mean time to first cannulation was 2.4±1.2 days (range, 1-15). Primary functional patency rate was 68.0% ± 10 at 6 and 12 months. Secondary patency rate was 93.3% ± 6 at 6 and 12 months. Pseudoaneurysm, bleeding, seroma, or graft infection was never observed.

Conclusions

In our experience, the Gore® Acuseal graft was useful and safe. Early cannulation was always performed, and structural complications did not occur. Primary functional and secondary patency rate are satisfactory in the short term.

Protein-energy wasting, as well as overweight and obesity, is a long-term risk factor for mortality in chronic hemodialysis patients

INTRODUCTION

In patients with end-stage renal disease on chronic hemodialysis (HD), protein-energy wasting (PEW) is very common and is associated with increased morbidity and mortality. Evaluation of nutritional status should be performed regularly in all such patients, using multiple methods. In this study, we analyzed the influence of several nutritional markers on long-term (5 years) survival of HD patients in one center. This is the first study on the long-term influence of nutritional status on mortality in dialysis patients ever conducted in Romania.

MATERIALS AND METHODS

We included all prevalent HD patients in our center. Those with ongoing acute illnesses and with inflammation (C-reactive protein ≥ 6.0 mg/l) were excluded. In the remaining subjects (N = 149, 82 males, mean age 55 years old), we performed the following measurements of nutritional status: estimation of dietary protein intake by normalized protein equivalent of nitrogen appearance (nPNA), subjective global assessment (SGA), body mass index (BMI), tricipital skinfold thickness, mid-arm circumference, assessment of body composition by bioelectrical impedance analysis (BIA), and pre-dialysis serum creatinine, albumin, and total cholesterol. We used receiver operating characteristic curves to determine the cutoff points for most of the variables, and we applied the Kaplan-Meier estimator and the Cox's proportional hazards model (stepwise method) to analyze the influence of these variables on survival.

RESULTS

In univariate analysis, general factors including age ≥ 65 years, male gender, dialysis vintage ≥ 2 years, and the presence of diabetes and heart failure were all significant predictors of mortality. Among nutritional parameters, BMI ≥ 25 kg/m(2), SGA-B (mild PEW), nPNA < 1.15 g/kg per day, and the BIA-derived phase angle (PhA) <5.58° were also significantly associated with reduced survival. All of these factors maintained statistical significance in multivariate analysis, except for male gender and heart failure.

CONCLUSION

We showed that low values of SGA, nPNA, and PhA independently predict mortality in HD patients. In conjunction with an earlier study, we demonstrated that the relative risk of death associated with these markers is highest during the first year of monitoring and it decreases in the following 4 years, although it still remains significantly increased. On the other hand, overweight and obesity were also associated with lower survival after 5 years, whereas this association was not apparent after 1 year.

Oral anticoagulant therapy in patients receiving haemodialysis: is it time to abandon it?

Oral anticoagulant (OAC) therapy in haemodialysis patients causes a great deal of controversy. This is because a number of pro- and anticoagulant factors play an important role in end-stage renal failure due to the nature of the disease itself. In these conditions, the pharmacokinetic and pharmacodynamic properties of the OACs used change as well. In the case of the treatment of venous thromboembolism, the only remaining option is OAC treatment according to regimens used for the general population. Prevention of HD vascular access thrombosis with the use of OACs is not very effective and can be dangerous. However, OAC treatment in patients with atrial fibrillation in dialysis population may be associated with an increase in the incidence of stroke and mortality. Doubts should be dispelled by prospective, randomised studies; at the moment, there is no justification for routine use of OACs in the above-mentioned indications. In selected cases of OAC therapy in this group of patients, it is absolutely necessary to control and monitor the applied treatment thoroughly. Indications for the use of OACs in patients with end-stage renal disease, including haemodialysis patients, should be currently limited.

Health status as a potential mediator of the association between hemodialysis vascular access and mortality

BACKGROUND

It is unknown whether the selection of healthier patients for arteriovenous fistula (AVF) placement explains higher observed catheter-associated mortality among elderly hemodialysis patients.

METHODS

From the United States Renal Data System 2005-2007, we used proportional hazard models to examine 117 277 incident hemodialysis patients aged 67-90 years for the association of initial vascular access type and 5-year mortality after accounting for health status. Health status was defined as functional status at dialysis initiation and number of hospital days within 2 years prior to dialysis initiation.

RESULTS

Patients with catheter alone had more limited functional status (25.5 versus 10.8% of those with AVF) and 3-fold more prior hospital days than those with AVF (mean 18.0 versus 5.4). In the unadjusted model, the likelihood of death was higher for arteriovenous grafts (AVG) {Hazard ratio (HR) 1.20 [95% CI (1.16-1.25)], catheter plus AVF [HR 1.34 (1.31-1.38)], catheter plus AVG [HR 1.46 (1.40-1.52)] and catheter only [HR 1.95 (1.90-1.99)]}, compared with AVF (P < 0.001). The association attenuated -23.7% (95% CI -22.0, -25.5) overall (AVF versus all other access types) after adjusting for the usual covariates (including sociodemographics, comorbidities and pre-dialysis nephrology care) {AVG [HR 1.21 (1.17-1.26)], catheter plus AVF [HR 1.27 (1.24-1.30)], catheter plus AVG [HR 1.38 (1.32-1.43)] and catheter only [HR 1.69 (1.66-1.73)], P < 0.001}. Additional adjustment for health status further attenuated the association by another -19.7% (-18.2, -21.3) overall but remained statistically significant <AVG [HR 1.18 (1.13-1.22)], catheter plus AVF [HR 1.20 (1.17-1.23)], catheter plus AVG {HR 1.38 [1.26 (1.21-1.31)]} and catheter only [HR 1.54 (1.50-1.58)], P < 0.001>.

CONCLUSIONS

The observed attenuation in mortality differences previously attributed to access type alone suggests the existence of selection bias. Nevertheless, the persistence of an apparent survival advantage after adjustment for health status suggests that AVF should still be the access of choice for elderly individuals beginning hemodialysis until more definitive data eliminating selection bias become available.

Disparities in arteriovenous fistula placement in older hemodialysis patients

The benefits of an arteriovenous fistula (AVF) as the preferred vascular access for hemodialysis have been clearly demonstrated. However, only about 20% of patients in the United States initiate hemodialysis with an AVF. In this study, we assessed whether disparities exist in the type of first hemodialysis access placed prior to dialysis start (rather than that used at dialysis initiation), to detect whether certain disadvantaged groups might have lower likelihood of AVF placement. Study cohort of 118,767 incident hemodialysis patients ≥67 years of age (1/2005-12/2008) derived from the United States Renal Data System was linked with Medicare claims data to identify the type of initial access placed predialysis. We used logistic regression model with outcome being the initial predialysis placement of an AVF as opposed to an arteriovenous graft or a central venous catheter. Increasing age, female sex, black race, lower body mass index, urban location, certain comorbidities, and shorter pre-end-stage renal disease nephrology care are all associated with a significantly lower likelihood of AVF placement as initial access predialysis. Our study suggests the presence of significant disparities in the placement of an AVF as initial hemodialysis vascular access. We suggest that additional attention should be paid to these patient groups to improve disparities by patient education, earlier referral, and close follow-up.

Serum catalytic Iron: A novel biomarker for coronary artery disease in patients on maintenance hemodialysis

Cardiovascular disease is the leading cause of morbidity and mortality in maintenance hemodialysis (MHD) patients. We evaluated the role of serum catalytic iron (SCI) as a biomarker for coronary artery disease (CAD) in patients on MHD. SCI was measured in 59 stable MHD patients. All patients underwent coronary angiography. Significant CAD was defined as a > 70% narrowing in at least one epicardial coronary artery. Levels of SCI were compared with a group of healthy controls. Significant CAD was detected in 22 (37.3%) patients, with one vessel disease in 14 (63.63%) and multi-vessel disease in eight (36.36%) patients. The MHD patients had elevated levels of SCI (4.70 ± 1.79 μmol/L) compared with normal health survey participants (0.11 ± 0.01 μmol/L) (P < 0.0001). MHD patients who had no CAD had SCI levels of 1.36 ± 0.34 μmol/L compared with those having significant CAD (8.92 ± 4.12 μmol/L) (P < 0.0001). Patients on MHD and diabetes had stronger correlation between SCI and prevalence of CAD compared with non-diabetics. Patients having one vessel disease had SCI of 8.85 ± 4.67 μmol/L versus multi-vessel disease with SCI of 9.05 ± 8.34 μmol/L, P = 0.48. In multivariate analysis, SCI and diabetes mellitus were independently associated with significant CAD. We confirm the high prevalence of significant CAD in MHD patients. Elevated SCI levels are associated with presence of significant coronary disease in such patients. The association of SCI is higher in diabetic versus the non-diabetic subgroup. This is an important potentially modifiable biomarker of CAD in MHD patients.

Sensitization from transfusion in patients awaiting primary kidney transplant

BACKGROUND

Sensitization to human leukocyte antigen (HLA) from red blood cell (RBC) transfusion is poorly quantified and is based on outdated, insensitive methods. The objective was to evaluate the effect of transfusion on the breadth, magnitude and specificity of HLA antibody formation using sensitive and specific methods.

METHODS

Transfusion, demographic and clinical data from the US Renal Data System were obtained for patients on dialysis awaiting primary kidney transplant who had ≥ 2 HLA antibody measurements using the Luminex single-antigen bead assay. One cohort included patients with a transfusion (n = 50) between two antibody measurements matched with up to four nontransfused patients (n = 155) by age, sex, race and vintage (time on dialysis). A second crossover cohort (n = 25) included patients with multiple antibody measurements before and after transfusion. We studied changes in HLA antibody mean fluorescence intensity (MFI) and calculated panel reactive antibody (cPRA).

RESULTS

In the matched cohort, 10 of 50 (20%) transfused versus 6 of 155 (4%) nontransfused patients had a ≥ 10 HLA antibodies increase of >3000 MFI (P = 0.0006); 6 of 50 (12%) transfused patients had a ≥ 30 antibodies increase (P = 0.0007). In the crossover cohort, the number of HLA antibodies increasing >1000 and >3000 MFI was higher in the transfused versus the control period, P = 0.03 and P = 0.008, respectively. Using a ≥ 3000 MFI threshold, cPRA significantly increased in both matched (P = 0.01) and crossover (P = 0.002) transfused patients.

CONCLUSIONS

Among prospective primary kidney transplant recipients, RBC transfusion results in clinically significant increases in HLA antibody strength and breadth, which adversely affect the opportunity for future transplant.

Initiation of dialysis should be timely: neither early nor late

Over the last decade, individuals with end-stage renal disease (ESRD) in the United States are starting maintenance dialysis therapy at progressively higher estimated glomerular filtration rate (eGFR). Moreover, several observational studies have demonstrated an association of a higher risk of death with higher serum creatinine-based estimates of GFR at the time of initiation of dialysis. In contrast, studies in which renal function has been measured by timed urinary collection show either a lower risk of death or no significant association with higher GFR at the time of initiation of dialysis. There are numerous potential sources of bias in such observational studies, particularly in those that use serum creatinine-based eGFR. The only randomized controlled clinical trial to have examined this question did not demonstrate either benefit or harm with initiation of dialysis at higher level of renal function. Thus, the data to date suggest that eGFR should not be the sole consideration when assessing the need for initiating maintenance dialysis in patients with advanced chronic kidney disease. Given the high societal costs of starting renal replacement therapy earlier in the course of the disease, these considerations also suggest that dialysis can be safely be postponed in otherwise asymptomatic individuals with advanced chronic kidney disease. By the same token, dialysis should not be denied to individuals who could clearly benefit from renal replacement therapy simply because the GFR is too high (viz., volume overload, refractory hyperkalemia). Finally, there is a compelling need to reexamine the symptoms that could be attributed to uremia and clearly improve upon initiation of dialysis to better guide clinical decision-making.

Chronic kidney disease and dialysis access in women

Chronic kidney disease currently affects one in nine Americans and over 500,000 have progressed to failure requiring kidney replacement therapy, with nearly 45% being women. Clinical Practice Guidelines have been developed in an effort to synthesize the latest literature, particularly randomized controlled trials, to assist clinical decision making. Women have different levels of kidney function than men at the same level of serum creatinine and may also lose kidney function over time more slowly than men. Although the arteriovenous fistulae have long been recognized as the preferred access for hemodialysis, women are less likely to initiate dialysis with an arteriovenous fistula in place. In addition, the female sex is regarded as a risk factor for access failure as well for complications such as steal. This article reviews treatment of women with chronic kidney disease, focusing on the difficulties they are perceived to have with dialysis access.

Pre Dialysis care and types of Vascular Access Employed in Incident Hemodialysis Patients: A study from Pakistan

OBJECTIVE

To determine frequency of different vascular access use in Incident hemodialysis (HD) patients and determine whether predialysis care in terms of timely advice for vascular access placement was better in the hands of nephrologist.

METHODS

A cross sectional study was conducted. Data was collected on the type of access used for first HD, including temporary Central venous catheters (CVC), permanent CVC (Permacath), arteriovenous fistula (AVF), or arteriovenous graft (AVG). In addition, information was also gathered if patients were aware of their renal disease and was followed by other physicians or nephrologist.

RESULTS

A total of 120 patients were enrolled in the study, 80% required CVC as their first access for HD (96/120 patients) out of which 74.2% were dialyzed through temporary catheter and 5.8% through Permacath. About 20% of patients were dialyzed through mature Arteriovenous (AV) access. Majority (95.8%) of patients were being followed by any health care provider. 68% of them were aware of their renal disease. About 55.8% were referred to nephrologist and 40% were followed by other physicians. About 83.5% of patients followed by nephrologist were advised AV access prior to commencing HD, compared to only 10.4% followed by other physicians (p<0.05). 24/61 (39.3%) patients that were advised AV access by both groups had timely made AV access and underwent HD by it.

CONCLUSION

Very high incidence of temporary HD catheter was used in Incident HD patients. Moreover, pre dialysis care in terms of placement of AV access prior to initiating HD is better in the hands of nephrologist and patients should be timely referred to nephrologist especially when they have Stage 4 chronic kidney disease (CKD).

Risk factors associated with peritoneal-dialysis-related peritonitis

Background. Peritonitis represents a major complication of peritoneal dialysis (PD). The aim of this paper was to systematically collect data on patient-related risk factors for PD-associated peritonitis, to analyze the methodological quality of these studies, and to summarize published evidence on the particular risk factors. Methods. Studies were identified by searches of Pubmed (1990–2012) and assessed for methodological quality by using a modified form of the STROBE criteria. Results. Thirty-five methodologically acceptable studies were identified. The following nonmodifiable risk factors were considered valid and were associated with an increased risk of peritonitis: ethnicity, female gender, chronic lung disease, coronary artery disease, congestive heart failure, cardiovascular disease, hypertension, antihepatitis C virus antibody positivity, diabetes mellitus, lupus nephritis or glomerulonephritis as underlying renal disease, and no residual renal function. We also identified the following modifiable, valid risk factors for peritonitis: malnutrition, overweight, smoking, immunosuppression, no use of oral active vitamin D, psychosocial factors, low socioeconomic status, PD against patient's choice, and haemodialysis as former modality. Discussion. Modifiable and nonmodifiable risk factors analyzed in this paper might serve as a basis to improve patient care in peritoneal dialysis.

When should a patient receive an arteriovenous graft rather than a fistula?

There has been a dramatic increase in the placement and use of arteriovenous fistulas (AVF) in US patients with chronic kidney disease over the past few years, in accordance with strong recommendations by Fistula First Initiative and KDOQI guidelines. However, AVF nonmaturation remains a substantial obstacle to achieving functional AVFs in a subset of patients, despite the widespread use of preoperative vascular mapping to assist surgeons in planning access surgery, and the growing use of interventions to salvage nonmaturing AVFs. In the right patient, aggressive efforts result in a functioning AVF, which provides adequate dialysis with relatively few interventions required to maintain its long-term patency for dialysis. In the wrong patient, aggressive efforts to achieve a mature AVF may result in numerous failed surgical and percutaneous procedures and prolonged catheter dependence, with all its associated complications. Thus, strict recommendations to place an AVF in all dialysis patients might not benefit every patient, and may actually harm some patients. There are no randomized clinical trials to address which patients are more suitable for placement of an arteriovenous graft (AVG), rather than an AVF. However, there is a wealth of observational studies, which taken cumulatively, may assist clinicians in identifying those patients who should receive an AVG. In this article, we review the relevant published literature regarding this topic and provide suggestions for stratifying patients who should receive each type of vascular access.

Outpatient red blood cell transfusion payments among patients on chronic dialysis

Background

Payments for red blood cell (RBC) transfusions are separate from US Medicare bundled payments for dialysis-related services and medications. Our objective was to examine the economic burden for payers when chronic dialysis patients receive outpatient RBC transfusions.

Methods

Using Truven Health MarketScan® data (1/1/02-10/31/10) in this retrospective micro-costing economic analysis, we analyzed data from chronic dialysis patients who underwent at least 1 outpatient RBC transfusion who had at least 6 months of continuous enrollment prior to initial dialysis claim and at least 30 days post-transfusion follow-up. A conceptual model of transfusion-associated resource use based on current literature was employed to estimate outpatient RBC transfusion payments. Total payments per RBC transfusion episode included screening/monitoring (within 3 days), blood acquisition/administration (within 2 days), and associated complications (within 3 days for acute events; up to 45 days for chronic events).

Results

A total of 3283 patient transfusion episodes were included; 56.4% were men and 40.9% had Medicare supplemental insurance. Mean (standard deviation [SD]) age was 60.9 (15.0) years, and mean Charlson comorbidity index was 4.3 (2.5). During a mean (SD) follow-up of 495 (474) days, patients had a mean of 2.2 (3.8) outpatient RBC transfusion episodes. Mean/median (SD) total payment per RBC transfusion episode was $854/$427 ($2,060) with 72.1% attributable to blood acquisition and administration payments. Complication payments ranged from mean (SD) $213 ($168) for delayed hemolytic transfusion reaction to $19,466 ($15,424) for congestive heart failure.

Conclusions

Payments for outpatient RBC transfusion episodes were driven by blood acquisition and administration payments. While infrequent, transfusion complications increased payments substantially when they occurred.

Methicillin-resistant Staphylococcus aureus nasal carriage among patients receiving hemodialysis in Taiwan: prevalence rate, molecular characterization and de-colonization

BACKGROUND

Staphylococcus aureus, particularly methicillin resistant (MRSA), is a common pathogen among patients receiving hemodialysis. To evaluate nasal carriage, molecular characterization and effectiveness of decolonization of MRSA among patients receiving hemodialysis in Taiwan, we conducted this study.

METHODS

From January to June 2011, two nasal samplings with a 3-month interval were obtained from patients undergoing hemodialysis in a medical center (CGMH), and in a local hospital (YMH) and sent for detection of MRSA. For MRSA carriers, decolonization procedures were administered. All patients in CGMH were observed if MRSA infections occurred during the study period.

RESULTS

A total of 529 nasal specimens (265 from CGMH and 264 from YMH) were collected from 296 patients (161 from CGMH and 135 from YMH). 233 patients participated in both surveys. Average one-time point MRSA carriage rate was 3.8%, and the rate was up to 6.9% for those with two-time point surveys. No additional significant factor for MRSA carriage was identified. Seventy percent of the 20 colonizing MRSA isolates, though categorized as healthcare-associated strains epidemiologically, shared common molecular characteristics of the local community-associated strains. Only one of the 20 MRSA-colonized patients failed decolonization and had persistent colonization, while without any intervention, 17 (61%) of 28 patients with methicillin-sensitive S. aureus colonization in the first survey had persistent colonization of a genetically indistinguishable strain. Within the study period, two patients (1.24%) in CGMH, one with MRSA colonization (9.1%), developed MRSA infection.

CONCLUSION

A substantial proportion of patients receiving hemodialysis in Taiwan had MRSA colonization, mostly genetically community strains. Decolonization procedures may effectively eliminate MRSA colonization and might reduce subsequent MRSA infection in these patients.

Clinical significance of upper-arm cephalic vein patency in autogenous radial-cephalic wrist fistulas for hemodialysis

OBJECTIVES

To investigate the significance of upper-arm cephalic veins (UACVs) in radial-cephalic arteriovenous fistulas (RCAVFs), the medical records of 183 patients who had undergone RCAVF creation were reviewed retrospectively.

METHODS

The patients were divided into two groups according to the status of the UACV upon preoperative venography: group A of 153 cases (83.6%) with a patent UACV and group B of 30 cases (16.3%) with a stenosed or occluded UACV. The clinical outcomes were compared.

RESULT

RCAVFs in group B had a significantly higher maturation failure rate (26.7% vs. 9.8%, p = 0.009) and lower primary/secondary patency rates (log-rank test, p < 0.0001) than those in the group A. The patients in group B required more frequent endovascular intervention to maintain access function (p = 0.002). The most common stenosis site was a draining vein in group B, in comparison to juxta-anastomosis in group A. In the multivariate analyses, the status of the UACV was an independent predictor of the primary and secondary patency rates of RCAVFs (p < 0.005).

CONCLUSION

UACV patency has a significant impact on clinical outcome for RCAVFs. When planning an RCAVF placement, venous status including the UACV should be considered.

Antibiotic lock technique for prevention of cuffed tunnel catheter associated bacteremia

BACKGROUND

Central venous cuffed tunnel catheters are commonly used for short term or long term hemodialysis access. However, catheter-associated bacteremia is a common complication. It has been suggested that the addition of antibiotics to the catheter during the interdialytic interval results in a decrease in bacterial colonization and thereby a decrease in catheter associated infections. To test this hypothesis, a prospective, randomized study was performed comparing a gentamicin citrate mixture to standard heparin as the catheter lock. The effect of covering the catheter hub in a sterile bag on the infection rate was additionally tested.

METHODS

From January 1999 to April 2000, all patients who underwent tunnel catheter placement or change (55 catheters) in the Nephrology Interventional Laboratory at Louisiana State University Health Sciences Center in Shreveport, were prospectively randomized as follows: group 1 (n=14): Antibiotic lock with tricitrasol (46.7%), gentamicin (40 mg/ml) and saline in a ratio of 1:5:5 and catheter hub covered with a sterile plastic bag after cleaning with a 10% povidone iodine solution; group 2 (n=22): Heparin lock and sterile plastic bag over catheter hub after cleaning with povidone iodine; and group 3 (n=19): Heparin lock alone. The primary end points of the study were catheter-associated bacteremia and thrombosis. Catheter loss due to access maturation, transplant or transfer were censored.

RESULTS

There were a total of 4,805 at risk patient-days. The total number of catheter associated bacteremias were one in group 1, four in group 2 and four in group 3. The number of catheter associated bacteremias per 1000 patient-days in each group was 0.62, 3.05, and 2.11 respectively. The sixty day percent survival of catheters in each group was 74 +/- 12, 55 +/- 12 and 59 +/- 11 respectively.

CONCLUSIONS

1) Tricitrasol and gentamicin as an antibiotic lock reduced the incidence of catheter associated bacteremia; 2) Covering the catheter hub with a sterile bag did not provide an additional advantage; 3) The antibiotic lock improved overall survival of catheters.

Independent prediction factors for primary patency loss in arteriovenous grafts within six months

PURPOSE

The objective of this study was to explore the association between loss of primary functional patency within 6 months of first use and demographic and clinical characteristics in patients with arteriovenous grafts (AVGs) receiving chronic hemodialysis. The knowledge and management of these characteristics will minimize the proportion of catheterdependent dialysis patients for whom AVGs are the best choice.

METHODS

This was a retrospective study of all chronic hemodialysis patients with AVGs followed by the Southern Alberta Renal Program from January 2005 to June 2008. Demographic and clinical variables and initial intra-access blood flow (IABF) were compared between those with and without loss of primary functional patency. To determine the contribution of independent variables to the dependant variable of loss of primary functional patency, a multivariable analysis using logistic regression was performed.

RESULTS

The incidence of primary failure was 30% (107/359). Multivariable analysis found that low initial IABF (<650 mL/ min, odds ratio [OR] 31, P < 0.001), presence of diabetes (OR 3.5, P = 0.001), older age (>65 years OR 3.2, P< 0.001), and presence of peripheral vascular disease (OR 2.5, P< 0.005) were independently associated with loss of primary patency.

CONCLUSIONS

AVGs are sometimes a better choice for those patients in which the time to and probability of successful fistula maturation may be a concern. Close monitoring of AVGs in patients with the identified risk factors associated with loss of primary patency may improve the life expectancy of the access.

Antibiotic catheter locks in the treatment of tunneled hemodialysis catheter-related blood stream infection

We prospectively examined the efficacy of systemic antibiotics and antibiotic catheter locks for the treatment of tunneled hemodialysis catheter related blood stream infections (CRBSI). Patients with clinical signs of tunnel or metastatic infection were excluded. All patients with suspected CRBSI were treated empirically with systemic antibiotics at the onset of symptoms before final culture and susceptibility results were available. Once the organism was identified, antibiotics treatment was tailored and antibiotic catheter locks were instilled after each dialysis treatment. Clearance of infection was documented by negative surveillance cultures after completion of antibiotic course. Out of 46 episodes of CRBSI; 16 were due to gram positive organisms, 22 were due to gram negative organisms, and 8 were polymicrobial (≥2 organisms) infections. 19 cases required removal of dialysis catheter. Antibiotic lock protocol was successful for eradicating infection in 27 of 46 episodes (59%). The likelihood of a clinical cure was identical in both gram-positive and gram-negative infections (63% and 62% respectively). Antibiotic lock protocol remains an option in the treatment of clinically stable patients with CRBSI; however, success rate of this protocol in eradicating the infection is modest.

Effect of fish oil supplementation on graft patency and cardiovascular events among patients with new synthetic arteriovenous hemodialysis grafts: a randomized controlled trial

CONTEXT

Synthetic arteriovenous grafts, an important option for hemodialysis vascular access, are prone to recurrent stenosis and thrombosis. Supplementation with fish oils has theoretical appeal for preventing these outcomes.

OBJECTIVE

To determine the effect of fish oil on synthetic hemodialysis graft patency and cardiovascular events.

DESIGN, SETTING, AND PARTICIPANTS

The Fish Oil Inhibition of Stenosis in Hemodialysis Grafts (FISH) study, a randomized, double-blind, controlled clinical trial conducted at 15 North American dialysis centers from November 2003 through December 2010 and enrolling 201 adults with stage 5 chronic kidney disease (50% women, 63% white, 53% with diabetes), with follow-up for 12 months after graft creation.

INTERVENTIONS

Participants were randomly allocated to receive fish oil capsules (four 1-g capsules/d) or matching placebo on day 7 after graft creation.

MAIN OUTCOME MEASURE

Proportion of participants experiencing graft thrombosis or radiological or surgical intervention during 12 months' follow-up.

RESULTS

The risk of the primary outcome did not differ between fish oil and placebo recipients (48/99 [48%] vs 60/97 [62%], respectively; relative risk, 0.78 [95% CI, 0.60 to 1.03; P = .06]). However, the rate of graft failure was lower in the fish oil group (3.43 vs 5.95 per 1000 access-days; incidence rate ratio [IRR], 0.58 [95% CI, 0.44 to 0.75; P < .001]). In the fish oil group, there were half as many thromboses (1.71 vs 3.41 per 1000 access-days; IRR, 0.50 [95% CI, 0.35 to 0.72; P < .001]); fewer corrective interventions (2.89 vs 4.92 per 1000 access-days; IRR, 0.59 [95% CI, 0.44 to 0.78; P < .001]); improved cardiovascular event-free survival (hazard ratio, 0.43 [95% CI, 0.19 to 0.96; P = .04]); and lower mean systolic blood pressure (-3.61 vs 4.49 mm Hg; difference, -8.10 [95% CI, -15.4 to -0.85]; P = .01).

CONCLUSIONS

Among patients with new hemodialysis grafts, daily fish oil ingestion did not decrease the proportion of grafts with loss of native patency within 12 months. Although fish oil improved some relevant secondary outcomes such as graft patency, rates of thrombosis, and interventions, other potential benefits on cardiovascular events require confirmation in future studies.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN15838383.

An experience of arteriovenous fistulas created for hemodialysis in the largest health center in eastern Turkey

BACKGROUND

The aim of the study was to evaluated the primary and secondary (after reoperation) patency rates and some effect factors in fistula patency for hemodialysis patients.

MATERIAL AND METHODS

Over a 10-year period, 1529 arteriovenous fistulas (AVFs) were fashioned in 1003 (611 males, 392 females; median age range 7-72) patients using the native vascular tissue and prosthetic graft material. We also evaluated the effects of various factors in fistula patency and primary and secondary patency rates in AVF patients.

RESULTS

The primary patencies of fistulas in this series were 72%, 64%, 51%, 41%, and 26%, and secondary patencies were 79%, 70%, 56%, 46%, and 33% at 6 months, 1, 2, 4, and 6 years, respectively. There was no statistically significant difference between the primary and secondary patencies (p = 0.082) in the 6-year follow-up. Factors affecting the patency of fistulas were diabetes mellitus (p < 0.005), hypertension (p < 0.005), and smoking habits (p < 0.005).

CONCLUSION

Even if shown to be not statistically significant, successful surgical revision after fistula occlusion improves secondary patency with potential benefits in terms of patient morbidity. Besides, the AVF patency was shortened in chronic renal-insufficiency patients with diabetes mellitus, hypertension, and smoking habits.

Historical clinical and economic consequences of anemia management in patients with end-stage renal disease on dialysis using erythropoietin stimulating agents versus routine blood transfusions: a retrospective cost-effectiveness analysis

OBJECTIVE

To determine whether Medicare's decision to cover routine administration of erythropoietin stimulating agents (ESAs) to treat anemia of end-stage renal disease (ESRD) has been a cost-effective policy relative to standard of care at the time.

METHODS

The authors used summary statistics from the actual cohort of ESRD patients receiving ESAs between 1995 and 2004 to create a simulated patient cohort, which was compared with a comparable simulated cohort assumed to rely solely on blood transfusions. Outcomes modeled from the Medicare perspective included estimated treatment costs, life-years gained, and quality-adjusted life-years (QALYs). Incremental cost-effectiveness ratio (ICER) was calculated relative to the hypothetical reference case of no ESA use in the transfusion cohort. Sensitivity of the results to model assumptions was tested using one-way and probabilistic sensitivity analyses.

RESULTS

Estimated total costs incurred by the ESRD population were $155.47B for the cohort receiving ESAs and $155.22B for the cohort receiving routine blood transfusions. Estimated QALYs were 2.56M and 2.29M, respectively, for the two groups. The ICER of ESAs compared to routine blood transfusions was estimated as $873 per QALY gained. The model was sensitive to a number of parameters according to one-way and probabilistic sensitivity analyses.

LIMITATIONS

This model was counter-factual as the actual comparison group, whose anemia was managed via transfusion and iron supplements, rapidly disappeared following introduction of ESAs. In addition, a large number of model parameters were obtained from observational studies due to the lack of randomized trial evidence in the literature.

CONCLUSIONS

This study indicates that Medicare's coverage of ESAs appears to have been cost effective based on commonly accepted levels of willingness-to-pay. The ESRD population achieved substantial clinical benefit at a reasonable cost to society.