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

The outcome of ultrasound-guided insertion of central hemodialysis catheter

OBJECTIVE

To point out our experience and assess the efficacy and safety of real-time ultrasound-guided central internal jugular vein (IJV) catheterization in the treatment of hemodialysis patients.

METHODS

This retrospective study comprised 150 patients with end-stage renal disease (ESRD) who had real-time ultrasonography (US)-guided IJV HD catheters placed in our hospital between March 2019 and March 2021. Patients were examined for their demographic data, etiology, site of catheter insertion, type (acute or chronic) of renal failure, technical success, operative time, number of needle punctures, and procedure-related complications. Patients who have had multiple catheter insertions, prior catheterization challenges, poor compliance, obesity, bony deformity, and coagulation disorders were considered at high-operative risk.

RESULTS

All patients experienced technical success. In terms of patient clinical features, an insignificant difference was observed between the normal and high-risk groups (p-value > 0.05). Of the 150 catheters, 62 (41.3%) were placed in high-risk patients. The first-attempt success rate was 89.8% for the normal group and 72.5% for the high-risk group (p = 0.006). IJV cannulation took less time in the normal-risk group compared to the highrisk group (21.2 ± 0.09) minutes vs (35.4 ± 0.11) minutes, (p < 0.001). There were no serious complications. During the placing of the catheter in the internal jugular vein, four patients (6.4%) experienced arterial puncture in the high-risk group. Two participants in each group got a small neck hematoma. One patient developed a pneumothorax in the high-risk group, which was managed with an intercostal chest tube insertion.

CONCLUSIONS

Even in the high-risk group, the real-time US-guided placement of a central catheter into the IJV is associated with a low complication rate and a high success rate. Even under US guidance, experience lowers complication rates. Real-time USguided is recommended to be used routinely during central venous catheter insertion.

A 2-year Comparative Analysis of Outcomes and Endovascular Interventions in Radio-Cephalic vs. Brachio-Cephalic Fistulae

BACKGROUND

Arterio-venous fistulae are often compromised by complications, notably thrombosis. We assess the 2 year follow-up data of a cohort of patients from a single vascular centre in the UK who underwent BCF or RCF creation with the objective of assessing the outcome differences and intervention rates between fistula types.

MATERIALS AND METHODS

We retrospectively assessed a cohort of 195 patients who underwent creation of arterio-venous fistula (100 BCF, 95 RCF) between January 2016 and December 2018, following them up for 2 years assessing the outcomes and interventions on their AVFs. The outcomes assessed were primary and cumulative patency at 6 weeks, 6, 12 and 24 months. Multinomial logistic regression to account for confounding variables age, gender, procedure, side, anticoagulant, vessel size and co-morbidities was performed. A Kaplan-Meier analysis of time to endovascular intervention was also performed comparing RCF and BCF.

RESULTS

Cumulative patency rates for BCF vs RCF were 91% vs. 89% at 6 weeks (X² (3, N = 194) = 4.70, P = .19), 83% vs. 76% at 6 months (X² (3, N = 188) = 7.72, P = .05), 78% vs. 69% at 12 months (X² (4, N = 175) = 5.37, P = .25) and 68% vs. 65% at 24 months (X² (4, N = 161) = 5.24, P = .24). Endovascular intervention rate becomes divergent at 5 months, with the steepest difference between 6 and 12 months. Comparative endovascular intervention rates between BCF and RCF were 20% vs. 31% at 6 months, 41% vs. 40% at 12 months and 40% vs. 49% at 24 months.

CONCLUSION

RCF seem to have significantly lower patency at 6 months and have higher endovascular intervention rates compared to BCF. A focussed surveillance protocol could prove effective in improving outcomes for RCF.

Simulator-based hemodialysis cannulation skills training: a new horizon?

In accordance with the recently released Kidney Disease Outcomes Quality Initiative  (KDOQI) guidelines, there is a significant need for focused efforts on improving hemodialysis cannulation outcomes. Toward this, structured and meaningful training of our clinical personnel who cannulate in dialysis clinics is a priority. With the availability of advanced sensors and computing methods, simulators could be indispensable tools for standardized skills assessment and training. In this article we present ways in which sensor data could be used to quantify cannulation skill. As with many other medical specialties, implementation of simulator-based training holds the promise of much-needed improvement in end-stage kidney disease patient outcomes.

Challenges and novel therapies for vascular access in haemodialysis

Advances in standards of care have extended the life expectancy of patients with kidney failure. However, options for chronic vascular access for haemodialysis - an essential part of kidney replacement therapy - have remained unchanged for decades. The high morbidity and mortality associated with current vascular access complications highlights an unmet clinical need for novel techniques in vascular access and is driving innovation in vascular access care. The development of devices, biological approaches and novel access techniques has led to new approaches to controlling fistula geometry and manipulating the underlying cellular and molecular pathways of the vascular endothelium, and influencing fistula maturation and formation through the use of external mechanical methods. Innovations in arteriovenous graft materials range from small modifications to the graft lumen to the creation of completely novel bioengineered grafts. Steps have even been taken to create new devices for the treatment of patients with central vein stenosis. However, these emerging therapies face difficult hurdles, and truly creative approaches to vascular access need resources that include well-designed clinical trials, frequent interaction with regulators, interventionalist education and sufficient funding. In addition, the heterogeneity of patients with kidney failure suggests it is unlikely that a 'one-size-fits-all' approach for effective vascular access will be feasible in the current environment.

Predictors of Arteriovenous Fistula Failure: A Post Hoc Analysis of the FAVOURED Study

Background

An autologous arteriovenous fistula (AVF) is the preferred hemodialysis vascular access, but successful creation is hampered by high rates of AVF failure. This study aimed to evaluate patient and surgical factors associated with AVF failure to improve vascular access selection and outcomes.

Methods

This is a post hoc analysis of all participants of FAVOURED, a multicenter, double-blind, multinational, randomized, placebo-controlled trial evaluating the effect of fish oil and/or aspirin in preventing AVF failure in patients receiving hemodialysis. The primary outcome of AVF failure was a composite of fistula thrombosis and/or abandonment and/or cannulation failure at 12 months post-AVF creation, and secondary outcomes included individual outcome components. Patient data (demographics, comorbidities, medications, and laboratory data) and surgical factors (surgical expertise, anesthetic, intraoperative heparin use) were examined using multivariable logistic regression analyses to evaluate associations with AVF failure.

Results

Of 536 participants, 253 patients (47%) experienced AVF failure during the study period. The mean age was 55±14.4 years, 64% were male, 45% were diabetic, and 4% had peripheral vascular disease. Factors associated with AVF failure included female sex (odds ratio [OR], 1.79; 95% confidence interval [CI], 1.20 to 2.68), lower diastolic BP (OR for higher DBP, 0.85; 95% CI, 0.74 to 0.99), presence of central venous catheter (OR, 1.49; 95% CI, 1.02 to 2.20; P=0.04), and aspirin requirement (OR, 1.60; 95% CI, 1.00 to 2.56).

Conclusions

Female sex, requirement for aspirin therapy, requiring hemodialysis via a central venous catheter, and lower diastolic BP were factors associated with higher odds of AVF failure. These associations have potential implications for vascular access planning and warrant further studies.

A Primer on Quality Assurance and Performance Improvement for Interprofessional Chronic Kidney Disease Care: A Path to Joint Commission Certification

Interprofessional care for chronic kidney disease facilitates the delivery of high quality, comprehensive care to a complex, at-risk population. Interprofessional care is resource intensive and requires a value proposition. Joint Commission certification is a voluntary process that improves patient outcomes, provides external validity to hospital administration and enhances visibility to patients and referring providers. This is a single-center, retrospective study describing quality assurance and performance improvement in chronic kidney disease, Joint Commission certification and quality outcomes. A total of 440 patients were included in the analysis. Thirteen quality indicators consisting of clinical and process of care indicators were developed and measured for a period of two years from 2009–2017. Significant improvements or at least persistently high performance were noted for key quality indicators such as blood pressure control (85%), estimation of cardiovascular risk (100%), measurement of hemoglobin A1c (98%), vaccination (93%), referrals for vascular access and transplantation (100%), placement of permanent dialysis access (61%), discussion of advanced directives (94%), online patient education (71%) and completion of office visit documentation (100%). High patient satisfaction scores (94–96%) are consistent with excellent quality of care provided.

Outcomes of initial hemodialysis vascular access in patients initiating dialysis with a tunneled catheter

BACKGROUND

Our aim was to determine factors that influence time to removal of tunneled hemodialysis catheter (THC), probability of repeat vascular access creation, and time to repeat vascular access.

METHODS

The Optum Clinformatics Data Mart claims database was queried from 2011 to 2017 for patients who initiated hemodialysis with a THC. Time from initial arteriovenous fistula (AVF)/graft (AVG) to THC removal and time to repeat AVF/AVG were analyzed using Cox proportional hazards. The likelihood of repeat AVF/AVG was analyzed using logistic regression.

RESULTS

A total of 8941 vascular access met the inclusion criteria: 6913 (77%) AVF and 2028 (23%) AVG. Median follow-up was 595 days among AVF patients (range, 1-2543 days) and 579 days among AVG patients (range, 1-2529 days). Patients undergoing AVF were younger, more likely to be male, of white race, and obese. Patients undergoing AVF were also slightly less likely to have diabetes, cardiac arrhythmia, congestive heart failure, and peripheral vascular disease than patients undergoing AVG. At 90 days and at 180 days after index access creation, significantly more patients who underwent index AVG had their THC removed compared with patients who underwent index AVF. By day 365, 78% of patients in both AVF and AVG had their THC removed. A total of 2550 (28.5%) patients underwent a repeat vascular access creation during the follow-up period: 30% of index AVF and 24% of index AVG. At 90 days, 180 days, and 365 days, significantly more patients in the index AVF group underwent a repeat vascular access creation than those in the index AVG group. Multivariate analysis demonstrated a significant interaction between vascular access type and age ≥70 years (P < .001) for time to THC removal, likelihood of repeat vascular access, and time to repeat vascular access. In the age <70 group, patients who underwent AVG were 60% more likely to have a shorter time to THC, had a 50.4% lower odds of repeat vascular access, and were 47% more likely to have a longer time to repeat vascular access compared with patients who underwent index AVF. In the age ≥70 group, patients who underwent AVG were 98% more likely to have a shorter time to THC removal, had 69.7% lower odds of repeat vascular access, and were 66% more likely to have a longer time to repeat vascular access.

CONCLUSIONS

Creation of AVG vs AVF significantly decreases the time to THC removal in dialysis-dependent patients, with a larger difference in patients aged ≥70 vs <70. Initial AVG was associated with lower odds of repeat vascular access and longer time to repeat vascular access. These results suggest that the dictum of "fistula first" is not appropriate for all patient populations and supports judicious use of AVG in achieving the more recent shift toward "catheter last."

Arteriovenous conduits for hemodialysis: how to better modulate the pathophysiological vascular response to optimize vascular access durability

Vascular access is the lifeline for patients on hemodialysis. Arteriovenous fistulas (AVFs) are the preferred vascular access, but AVF maturation failure remains a significant clinical problem. Currently, there are no effective therapies available to prevent or treat AVF maturation failure. AVF maturation failure frequently results from venous stenosis at the AVF anastomosis, which is secondary to poor outward vascular remodeling and excessive venous intimal hyperplasia that narrows the AVF lumen. Arteriovenous grafts (AVGs) are the next preferred vascular access when an AVF creation is not possible. AVG failure is primarily the result of venous stenosis at the vein-graft anastomosis, which originates from intimal hyperplasia development. Although there has been advancement in our knowledge of the pathophysiology of AVF maturation and AVG failure, this has not translated into effective therapies for these two important clinical problems. Further work will be required to dissect out the mechanisms of AVF maturation failure and AVG failure to develop more specific therapies. This review highlights the major recent advancements in AVF and AVG biology, reviews major clinical trials, and discusses new areas for future research.

Interventions for treating central venous haemodialysis catheter malfunction

BACKGROUND

Adequate haemodialysis (HD) in people with end-stage kidney disease (ESKD) is reliant upon establishment of vascular access, which may consist of arteriovenous fistula, arteriovenous graft, or central venous catheters (CVC). Although discouraged due to high rates of infectious and thrombotic complications as well as technical issues that limit their life span, CVC have the significant advantage of being immediately usable and are the only means of vascular access in a significant number of patients. Previous studies have established the role of thrombolytic agents (TLA) in the prevention of catheter malfunction. Systematic review of different thrombolytic agents has also identified their utility in restoration of catheter patency following catheter malfunction. To date the use and efficacy of fibrin sheath stripping and catheter exchange have not been evaluated against thrombolytic agents.

OBJECTIVES

This review aimed to evaluate the benefits and harms of TLA, preparations, doses and administration as well as fibrin-sheath stripping, over-the-wire catheter exchange or any other intervention proposed for management of tunnelled CVC malfunction in patients with ESKD on HD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 17 August 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

We included all studies conducted in people with ESKD who rely on tunnelled CVC for either initiation or maintenance of HD access and who require restoration of catheter patency following late-onset catheter malfunction and evaluated the role of TLA, fibrin sheath stripping or over-the-wire catheter exchange to restore catheter function. The primary outcome was be restoration of line patency defined as ≥ 300 mL/min or adequate to complete a HD session or as defined by the study authors. Secondary outcomes included dialysis adequacy and adverse outcomes.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed retrieved studies to determine which studies satisfy the inclusion criteria and carried out data extraction. Included studies were assessed for risk of bias. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using GRADE.

MAIN RESULTS

Our search strategy identified 8 studies (580 participants) as eligible for inclusion in this review. Interventions included: thrombolytic therapy versus placebo (1 study); low versus high dose thrombolytic therapy (1); alteplase versus urokinase (1); short versus long thrombolytic dwell (1); thrombolytic therapy versus percutaneous fibrin sheath stripping (1); fibrin sheath stripping versus over-the-wire catheter exchange (1); and over-the-wire catheter exchange versus exchange with and without angioplasty sheath disruption (1). No two studies compared the same interventions. Most studies had a high risk of bias due to poor study design, broad inclusion criteria, low patient numbers and industry involvement.Based on low certainty evidence, thrombolytic therapy may restore catheter function when compared to placebo (149 participants: RR 4.05, 95% CI 1.42 to 11.56) but there is no data available to suggest an optimal dose or administration method. The certainty of this evidence is reduced due to the fact that it is based on only a single study with wide confidence limits, high risk of bias and imprecision in the estimates of adverse events (149 participants: RR 2.03, 95% CI 0.38 to 10.73).Based on the available evidence, physical disruption of a fibrin sheath using interventional radiology techniques appears to be equally efficacious as the use of a pharmaceutical thrombolytic agent for the immediate management of dysfunctional catheters (57 participants: RR 0.92, 95% CI 0.80 to 1.07).Catheter patency is poor following use of thrombolytic agents with studies reporting median catheter survival rates of 14 to 42 days and was reported to improve significantly by fibrin sheath stripping or catheter exchange (37 participants: MD -27.70 days, 95% CI -51.00 to -4.40). Catheter exchange was reported to be superior to sheath disruption with respect to catheter survival (30 participants: MD 213.00 days, 95% CI 205.70 to 220.30).There is insufficient evidence to suggest any specific intervention is superior in terms of ensuring either dialysis adequacy or reduced risk of adverse events.

AUTHORS' CONCLUSIONS

Thrombolysis, fibrin sheath disruption and over-the-wire catheter exchange are effective and appropriate therapies for immediately restoring catheter patency in dysfunctional cuffed and tunnelled HD catheters. On current data there is no evidence to support physical intervention over the use of pharmaceutical agents in the acute setting. Pharmacological interventions appear to have a bridging role and long-term catheter survival may be improved by fibrin sheath disruption and is probably superior following catheter exchange. There is no evidence favouring any of these approaches with respect to dialysis adequacy or risk of adverse events.The current review is limited by the small number of available studies with limited numbers of patients enrolled. Most of the studies included in this review were judged to have a high risk of bias and were potentially influenced by pharmaceutical industry involvement.Further research is required to adequately address the question of the most efficacious and clinically appropriate technique for HD catheter dysfunction.

An Open-Source Ultrasound Software for Diagnosis of Fistula Maturation

Vascular access is essential for hemodialysis patients. The mature native arteriovenous fistula has been the preferred vascular access for hemodialysis, because it has greater longevity than synthetic grafts. However, once surgically created, fistulas often fail to develop (mature) into viable points of vascular access, requiring surgical or radiologic interventions before their use. Because maturation depends on vascular mechanics (e.g., distensibility and wall shear), we developed open-source ultrasound software to investigate these metrics clinically. We demonstrated in a single patient the ability of the software for consistent measurements from various locations within a cardiac cycle and between different cardiac cycles. We further assessed the ability of the software to identify changes in distensibility of a patient's fistula from 1 to 6 weeks postoperation. The routine frame rates of clinical machines demonstrated high fidelity tracking within cardiac cycles (coefficient of variation [CV] = 2.4% ± 0.011) and between cardiac cycles (CV = 2.4% ± 0.004). The distensibility of the patient's fistula from 1 to 6 weeks postoperation increased from 4% to 7% in the arterial inflow and from 3% to 4% in the postarterial anastomotic segment (PAAS). In contrast, the distensibility of the outflow vein decreased from 4% to 2%. These results corroborate that in addition to diameter changes, the mechanical properties of the vascular segments changed during fistula maturation. This demonstrates that our software-based approach may allow ultrasound-based mechanical measurements to become more accessible for wider clinical research.

[Exhaustion of vascular capital in patients on hemodialysis: what will be the outcome?]

Despite advances in the treatment of chronic renal failure, vascular access remains the weakest link in renal replacement therapy (RRT) and the leading cause of morbidity in patients on hemodialysis We report the case of a young female patient with chronic renal insufficiency secondary to vascular nephropathy on periodic hemodialysis and whose vascular capital was early exhausted due to iterative thromboses in arteriovenous fistulas and failure in peritoneal dialysis. Protein C deficiency was objectified. The patient underwent tunneled hemodialysis catheter insertion at the level of the right atrium via a right anterolateral thoracotomy with cannulation of the inferior vena cava, with poor functional outcome after three months of use. Since then she has been dialyzed using puncture of the external jugular veins.

The molecular mechanisms of hemodialysis vascular access failure

The arteriovenous fistula has been used for more than 50 years to provide vascular access for patients undergoing hemodialysis. More than 1.5 million patients worldwide have end stage renal disease and this population will continue to grow. The arteriovenous fistula is the preferred vascular access for patients, but its patency rate at 1 year is only 60%. The majority of arteriovenous fistulas fail because of intimal hyperplasia. In recent years, there have been many studies investigating the molecular mechanisms responsible for intimal hyperplasia and subsequent thrombosis. These studies have identified common pathways including inflammation, uremia, hypoxia, sheer stress, and increased thrombogenicity. These cellular mechanisms lead to increased proliferation, migration, and eventually stenosis. These pathways work synergistically through shared molecular messengers. In this review, we will examine the literature concerning the molecular basis of hemodialysis vascular access malfunction.

High Preoperative Neutrophil-Lymphocyte Ratio (NLR) and Red Blood Cell Distribution Width (RDW) as Independent Predictors of Native Arteriovenous Fistula Failure

Objective: To study the association between a high preoperative neutrophil lymphocyte ratio (NLR) and red cell distribution width (RDW) with arteriovenous fistula (AVF) failure, as well as to determine the cut-off values in a South Asian population.

Materials and Methods: A total of 150 consecutive patients with a failed fistula who presented in the Department of Vascular Surgery between January 2014 and January 2016. Patients fulfilling the inclusion criteria were selected as defined as Case. They were compared with 150 patients who had matured fistulae (Control).

Results: A significant difference was found between the Case and Control groups in mean preoperative NLR (3.3±0.5 versus 2.2±0.9, P value=0.011) and RDW (15.9±2.9 versus 13.6±1.1%, P value of 0.02), respectively. Multivariate analysis revealed that NLR (Odds Ratios (OR) 1.39; 95% Confidence Intervals (CI) 1.02 to 2.08; P<0.001) and RDW (OR 1.39; 95%CI 1.11 to 1.69; P<0.001) were strong independent predictors of AVF failure. A receiver operating characteristic curve analysis showed a cut-off value of 2.65 (specificity 80%, sensitivity 98%) and 15.1 (specificity 79%, sensitivity 98%) for NLR and RDW, respectively.

Conclusion: Increased preoperative NLR and RDW were associated with a high rate of AVF failure in a South Asian population.

Factors associated with the receipt of antimicrobials among chronic hemodialysis patients

BACKGROUND

Antimicrobial use is common among patients receiving chronic hemodialysis (CHD) and may represent an important antimicrobial stewardship opportunity. The objective of this study is to characterize CHD patients at increased risk of receiving antimicrobials, including not indicated antimicrobials.

METHODS

We conducted a prospective cohort study over a 12-month period among patients receiving CHD in 2 outpatient dialysis units. Each parenteral antimicrobial dose administered was characterized as indicated or not indicated based on national guidelines. Patient factors associated with receipt of antimicrobials and receipt of ≥1 inappropriate antimicrobial dose were analyzed.

RESULTS

A total of 89 of 278 CHD patients (32%) received ≥1 antimicrobial doses and 52 (58%) received ≥1 inappropriately indicated dose. Patients with tunneled catheter access, a history of colonization or infection with a multidrug-resistant organism, and receiving CHD sessions during daytime shifts were more likely to receive antimicrobials (odds ratio [OR], 5.16; 95% confidence interval [CI], 2.72-9.80; OR, 5.43; 95% CI, 1.84-16.06; OR, 4.59; 95% CI, 1.20-17.52, respectively). Patients with tunneled catheter access, receiving CHD at dialysis unit B, and with a longer duration of CHD prior to enrollment were at higher risk of receiving an inappropriately indicated antimicrobial dose (incidence rate ratio, 2.23; 95% CI, 1.16-4.29; incidence rate ratio, 2.67; 95% CI, 1.34-5.35; incidence rate ratio, 1.11; 95% CI, 1.01-1.23, respectively).

CONCLUSIONS

This study of all types of antimicrobials administered in 2 outpatient dialysis units identified several important factors to consider when developing antimicrobial stewardship programs in this health care setting.

Comparison of treatment delay associated with tunneled hemodialysis catheter placement between interventionists

BACKGROUND/AIMS

Fragmented care in nephrology can cause treatment delays. Nephrologists are qualified to perform vascular access-related procedures because they understand the pathophysiology of renal disease and perform physical examination for vascular access. We compared treatment delays associated with tunneled hemodialysis catheter (TDC) placement between interventional radiologists and nephrologists.

METHODS

We collected data by radiologists from January 1, 2011 through December 31, 2011 and by nephrologists from since July 1, 2012 through June 30, 2013. We compared the duration from the hemodialysis decision to TDC placement (D-P duration) and hemodialysis initiation (D-H duration), catheter success and the complication rate, and the frequency and the usage time of non-tunneled hemodialysis catheters (NDCs) before TDC placement.

RESULTS

The study analyzed 483 placed TDCs: 280 TDCs placed by radiologists and 203 by nephrologists. The D-P durations were 319 minutes (interquartile range [IQR], 180 to 1,057) in the radiologist group and 140 minutes (IQR, 0 to 792) in the nephrologist group. Additionally, the D-H durations were 415 minutes (IQR,260 to 1,091) and 275 minutes (IQR, 123 to 598), respectively. These differences were statistically significant (p = 0.00). The TDC success rate (95.3% vs. 94.5%, respectively; p = 0.32) and complication rate (16.2% vs. 11%, respectively; p = 0.11) did not differ between the groups. The frequency (24.5 vs. 26%, respectively; p = 0.72) and the usage time of NDC (8,451 vs. 8,416 minutes, respectively; p = 0.91) before TDC placement were not statistically significant.

CONCLUSIONS

Trained interventional nephrologists could perform TDC placement safely, minimizing treatment delays.

The Biology of Hemodialysis Vascular Access Failure

Arteriovenous fistulas (AVFs) are essential for patients and clinicians faced with end-stage renal disease (ESRD). While this method of vascular access for hemodialysis is preferred to others due to its reduced rate of infection and complications, they are plagued by intimal hyperplasia. The pathogenesis of intimal hyperplasia and subsequent thrombosis is brought on by uremia, hypoxia, and shear stress. These forces upregulate inflammatory and proliferative cytokines acting on leukocytes, fibroblasts, smooth muscle cells, and platelets. This activation begins initially with the progression of uremia, which induces platelet dysfunction and primes the body for an inflammatory response. The vasculature subsequently undergoes changes in oxygenation and shear stress during AVF creation. This propagates a strong inflammatory response in the vessel leading to cellular proliferation. This combined response is then further subjected to the stressors of cannulation and dialysis, eventually leading to stenosis and thrombosis. This review aims to help interventional radiologists understand the biological changes and pathogenesis of access failure.

Antimicrobial lock solutions for the prevention of catheter-related infection in patients undergoing haemodialysis: study protocol for network meta-analysis of randomised controlled trials

INTRODUCTION

Catheter-related infection (CRI) is a difficult clinical problem in renal medicine, with blood stream infections occurring in up to 40% of patients with haemodialysis (HD) catheters, conferring significant rates of morbidity and mortality. Several approaches have been assessed as a means to prevent CRI. Currently, an intervention that is the source of much discussion is the use of antimicrobial lock solutions (ALS). A number of past conventional meta-analyses have compared different ALS with heparin. However, there is no consensus recommendation regarding which type of ALS is best. The purpose of our study is to carry out a network meta-analysis comparing the efficacy of different ALS for prevention of CRI in patients with HD and ranking these ALS for practical consideration.

METHODS AND ANALYSIS

We will search six electronic databases, earlier relevant meta-analyses and reference lists of included studies for randomised controlled trials (RCTs) that compared ALS for preventing episodes of CRI in patients with HD either head-to-head or against control interventions using non-ALS. Study selection and data collection will be performed by two reviewers independently. The Cochrane Risk of Bias Tool will be used to assess the quality of included studies. The primary outcome of efficacy will be catheter-related bloodstream infection (CRBSI). We will perform a Bayesian network meta-analysis to compare the relative efficacy of different ALS by WinBUGS (V.1.4.3) and STATA (V.13.0). The quality of evidence will be assessed by GRADE.

ETHICS AND DISSEMINATION

Ethical approval is not required given that this study includes no confidential personal data and no data on interventions on patients. The results of this study will be submitted to a peer-review journal for publication.

TRIAL REGISTRATION NUMBER

CRD42015027010.

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.

Predictive parameters of arteriovenous fistula functional maturation in a population of patients with end-stage renal disease

INTRODUCTION

With increasing numbers of patients diagnosed with ESRD, arteriovenous fistula (AVF) maturation has become a major factor in improving both dialysis related outcomes and quality of life of those patients. Compared to other types of access it has been established that a functional AVF access is the least likely to be associated with thrombosis, infection, hospital admissions, secondary interventions to maintain patency and death.

AIM

Study of demographic factors implicated in the functional maturation of arteriovenous fistulas. Also, to explore any possible association between preoperative haematological investigations and functional maturation.

METHODS

We performed a retrospective chart review of all patients with ESRD who were referred to the vascular service in the University Hospital of Limerick for creation of vascular access for HD. We included patients with primary AVFs; and excluded those who underwent secondary procedures.

RESULTS

Overall AVF functional maturation rate in our study was 53.7% (52/97). Female gender showed significant association with nonmaturation (P = 0.004) and was the only predictor for non-maturation in a logistic regression model (P = 0.011). Patients who had history of renal transplant (P = 0.036), had relatively lower haemoglobin levels (P = 0.01) and were on calcium channel blockers (P = 0.001) showed better functional maturation rates.

CONCLUSION

Female gender was found to be associated with functional non-maturation, while a history kidney transplant, calcium channel-blocker agents and low haemoglobin levels were all associated with successful functional maturation. In view of the conflicting evidence in the literature, large prospective multi-centre registry-based studies with well-defined outcomes are needed.

Critical and honest conversations: the evidence behind the "Choosing Wisely" campaign recommendations by the American Society of Nephrology

Estimates suggest that one third of United States health care spending results from overuse or misuse of tests, procedures, and therapies. The American Board of Internal Medicine Foundation, in partnership with Consumer Reports, initiated the "Choosing Wisely" campaign to identify areas in patient care and resource use most open to improvement. Nine subspecialty organizations joined the campaign; each organization identified five tests, procedures, or therapies that are overused, are misused, or could potentially lead to harm or unnecessary health care spending. Each of the American Society of Nephrology's (ASN's) 10 advisory groups submitted recommendations for inclusion. The ASN Quality and Patient Safety Task Force selected five recommendations based on relevance and importance to individuals with kidney disease.Recommendations selected were: (1) Do not perform routine cancer screening for dialysis patients with limited life expectancies without signs or symptoms; (2) do not administer erythropoiesis-stimulating agents to CKD patients with hemoglobin levels ≥10 g/dl without symptoms of anemia; (3) avoid nonsteroidal anti-inflammatory drugs in individuals with hypertension, heart failure, or CKD of all causes, including diabetes; (4) do not place peripherally inserted central catheters in stage 3-5 CKD patients without consulting nephrology; (5) do not initiate chronic dialysis without ensuring a shared decision-making process between patients, their families, and their physicians.These five recommendations and supporting evidence give providers information to facilitate prudent care decisions and empower patients to actively participate in critical, honest conversations about their care, potentially reducing unnecessary health care spending and preventing harm.

Placement of hemodialysis catheters with a technical, functional, and anatomical viewpoint

Aims. Vascular access is of prime importance for hemodialysis patients. We aimed to study early complications of hemodialysis catheters placed in different central veins in patients with acute or chronic renal failure with or without ultrasound (US ) guidance. Material and Methods. Patients who were admitted to our unit between March 2008 and December 2010 with need for vascular access have been included. 908 patients were examined for their demographic parameters, primary renal disease, and indication for catheterization, type and location of the catheter, implantation technique, and acute complications. Results. The mean age of the patients was 60.6 ± 16.0 years. 643 (70.8 %) of the catheters were temporary while 265 (29.2%) were permanent. 684 catheters were inserted to internal jugular veins, 213 to femoral, and 11 to subclavian veins. Arterial puncture occurred in 88 (9.7%) among which 13 had resultant subcutaneous hematoma. No patient had lung trauma and there had been no need for removal of the catheter or a surgical intervention for complications. US guidance in jugular vein and experience of operator decreased arterial puncture rate. Conclusion. US-guided replacement of catheter to internal jugular vein would decrease complication rate. Referral to invasive nephrologists may decrease use of subclavian vein. Experience improves complication rates even under US guidance.

Unused Arteriovenous Grafts as a Source of Chronic Infection in Haemodialysed Patients with Relevance to Diagnosis of Fluorodeoxyglucose PET/CT Examination

Introduction: Clotted arteriovenous grafts (AVG) for haemodialysis which are not used (silent grafts) can serve as a potential source of chronic bacterial infection in patients on dialysis programs. In some cases, the local finding is unclear. The patient only suffers from repeated metastatic infection and the detection of AVG infection is difficult. Nuclear medicine methods have the potential to uncover AVG infection. In this study, we correlated the positron emission tomography (PET)/ computed tomography (CT) findings of the AVG examination with the microbiological findings from removed grafts. The aim was to evaluate the relevance of the Fluorodeoxyglucose (FDG) PET/CT method in detecting clotted graft infection. Material and Methods: A cohort of 13 patients with clotted grafts were followed-up. Four patients had overall symptoms of infection and 9 patients were asymptomatic. In all cases, the PET CT examination and microbiological examination of the removed graft were provided. Results: Only one mismatch—negative PET CT finding and positive microbiological culture was recorded in the 13 followed-up patients. Conclusion: In patients with silent grafts and recurrent infection of equivocal aetiology, PET CT examination can contribute to the diagnosis of AVG infection and, subsequently, to prevent further infectious complications, if the AVG infection is treated appropriately and the graft is removed. Key words: ePTFE prosthesis, Nuclear medicine imaging, Staphylococcus aureus, Vascular access infection

Epidemiology of end-stage renal disease in the countries of the Gulf Cooperation Council: a systematic review

Objectives

To describe the epidemiology of end stage renal disease (ESRD).

Design

Mixed-methods systematic review.

Setting

The countries of the Gulf Cooperation Council (GCC) which consist of Saudi Arabia, the United Arab Emirates, Kuwait, Qatar, Bahrain, and Oman.

Participants

Defined to have ESRD or patients on regular dialysis for a minimum dialysis period of at least three months. Since many outcomes were reviewed, studies that estimated the incidence and prevalence of ESRD as outcomes should not have defined the study population as ESRD population or patients on regular dialysis. Studies where the study population mainly comprised children or pregnant woman were excluded.

Main outcome measures

The trends of the incidence, prevalence, and mortality rate of ESRD; also, causes of mortality, primary causes and co-morbid conditions associated with ESRD.

Results

44 studies included in this review show that the incidence of ESRD has increased while the prevalence and mortality rate of ESRD in the GCC has not been reported sufficiently. The leading primary causes of ESRD recorded in the countries of the GCC is diabetes with the most prevalent co-morbid conditions being Hypertension and Hepatitis C Virus infection; the most common cause of death was cardiovascular disease and sepsis.

Conclusions

This review highlights that the lack of national renal registries data is a critical issue in the countries of the GCC. The available data also do not provide an accurate and updated estimate for relevant outcomes. Additionally, considering the increasing burden of chronic kidney disease (CKD), these results stressed the needs and the importance of preventative strategies for leading causes of ESRD. Furthermore, more studies are needed to describe the epidemiology of ESRD and for assessing the overall quality of renal care.

Association between prior peripherally inserted central catheters and lack of functioning arteriovenous fistulas: a case-control study in hemodialysis patients

BACKGROUND

Although an arteriovenous fistula (AVF) is the hemodialysis access of choice, its prevalence continues to be lower than recommended in the United States. We assessed the association between past peripherally inserted central catheters (PICCs) and lack of functioning AVFs.

STUDY DESIGN

Case-control study.

PARTICIPANTS & SETTING

Prevalent hemodialysis population in 7 Mayo Clinic outpatient hemodialysis units. Cases were without functioning AVFs and controls were with functioning AVFs on January 31, 2011.

PREDICTORS

History of PICCs.

OUTCOMES

Lack of functioning AVFs.

RESULTS

On January 31, 2011, a total of 425 patients were receiving maintenance hemodialysis, of whom 282 were included in this study. Of these, 120 (42.5%; cases) were dialyzing through a tunneled dialysis catheter or synthetic arteriovenous graft and 162 (57.5%; controls) had a functioning AVF. PICC use was evaluated in both groups and identified in 30% of hemodialysis patients, with 54% of these placed after dialysis therapy initiation. Cases were more likely to be women (52.5% vs 33.3% in the control group; P = 0.001), with smaller mean vein (4.9 vs 5.8 mm; P < 0.001) and artery diameters (4.6 vs 4.9 mm; P = 0.01) than controls. A PICC was identified in 53 (44.2%) cases, but only 32 (19.7%) controls (P < 0.001). We found a strong and independent association between PICC use and lack of a functioning AVF (OR, 3.2; 95% CI, 1.9-5.5; P < 0.001). This association persisted after adjustment for confounders, including upper-extremity vein and artery diameters, sex, and history of central venous catheter (OR, 2.8; 95% CI, 1.5-5.5; P = 0.002).

LIMITATIONS

Retrospective study, participants mostly white.

CONCLUSION

PICCs are commonly placed in patients with end-stage renal disease and are a strong independent risk factor for lack of functioning AVFs.

Hispanic ethnicity and vascular access use in patients initiating hemodialysis in the United States

BACKGROUND AND OBJECTIVES

Hispanics are the largest minority in the United States (comprising 16.3% of the US population) and have 1.5 times the age-, sex-, and race-adjusted incidence of ESRD compared with non-Hispanics. Poor health care access and low-quality care generally received by Hispanics are well documented. However, little is known regarding dialysis preparation of Hispanic patients with progressive CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using data from Medical Evidence Report form CMS-2728-U3, 321,996 adult patients of white or black race were identified who initiated hemodialysis (HD) between July 1, 2005 and December 31, 2008. The form captures Hispanic ethnicity, vascular access use at first outpatient HD, sociodemographic characteristics, and comorbidities. This study also examined whether use of an arteriovenous fistula (AVF) or graft (AVG) was reported.

RESULTS

AVF/AVG use was reported in 14.5% of Hispanics and 17.6% in non-Hispanics (P<0.001). The unadjusted prevalence ratio (PR) was 0.85 (95% confidence interval [95% CI], 0.83-0.88), indicating that Hispanics were 15% less likely to use AVG/AVF for their first outpatient HD. Adjustment for age, sex, and race, as well as a large number of comorbidities and frailty indicators, did not change this association (PR, 0.85; 95% CI, 0.83-0.88). Further adjustment for timing of first predialysis nephrology care, however, attenuated the PR by two-thirds (PR, 0.94; 95% CI, 0.92-0.97).

CONCLUSIONS

Hispanics are less likely to use arteriovenous access for first outpatient HD compared with non-Hispanics, which seems to be explained by variation in the access to predialysis nephrology care.

Racial and gender differences in arteriovenous fistula use among incident hemodialysis patients

BACKGROUND

Arteriovenous fistula (AVF) use is reported to differ among racial and gender groups. We sought to identify risk factors associated with incident AVF and whether racial and gender differences in AVF use persist after controlling for these factors.

METHODS

We evaluated 28,712 incident adult hemodialysis patients (age ≥ 18) from five ESRD networks starting dialysis between June 1, 2005 and May 31, 2006. Data were obtained from the Center for Medicaid and Medicare Services 2728 form.

RESULTS

Incident AVF use was reported for 11% of black and 12% of white patients [OR = 0.89 (95% CI: 0.83, 0.96)], and for 9% of females and 13% of males [OR = 0.66 (0.62-0.71)]. After adjusting for facility clustering, blacks were as likely as whites to use an AVF [OR = 1.00 (0.92-1.09)], while gender differences persisted [OR = 0.64 (0.59-0.69)]. Compared to patients with no renal care prior to dialysis initiation, incident AVF use was 16-fold greater among those with ≥ 12 months of nephrology care [OR = 15.99 (13.25-19.29)], 9-fold greater among those with 6-12 months of care [OR = 9.00 (7.45-10.88)] and 7-fold greater among those with at least 6 months of care [OR = 7.13 (5.73-8.88)].

CONCLUSION

Racial, but not gender, differences in incident AVF use were eliminated after accounting for clustering within facilities.

Costs of dialysis--a regional population-based analysis

BACKGROUND

Population-based estimates of costs of renal replacement therapy are scarce in the literature. The aim of our study was to calculate the costs of long-term dialysis in 2006 on the basis of patient-specific data from a well-defined population in a region in western Germany (n = 310,757).

METHODS

Cost estimation was performed from the perspective of the statutory health insurance. All dialysis patients from the study region (n = 344, 54% male, mean age (+/-SD) 69 +/- 13 years, 42% diabetic) were assessed for the costs of the dialysis procedures, dialysis-related hospital admissions, outpatient contacts outside of our dialysis center, dialysis-related medication, patient transportation and related costs (e.g. reimbursement fees on the basis of the German diagnosis-related group system, price scales). We estimated the cumulative cost per patient year in 2006 (in Euros), along with the 10th and 90th percentiles and the 95% confidence intervals (CI) by using bootstrapping procedures.

RESULTS

The mean total dialysis-related cost in 2006 was 54,777 Euros (95% CI, 51,445-65,705) per patient year. The largest part of the costs (55%) was caused by the dialysis procedures, followed by the costs of medication (22%), hospitalization (14%) and transportation (8%). The total cost increased significantly with increasing age. No significant association was found between total cost and sex, dialysis strategy, end-stage renal disease duration and diabetes.

CONCLUSIONS

We present for the first time a cost estimation of dialysis in Germany on the basis of patient-level data in a population-based sample. Except age, patient characteristics were not significantly associated with costs. The largest part of the costs was caused by the dialysis procedures themselves; however, other dialysis-specific health care utilization also strongly contributed to the total cost.

Systematic review of antimicrobials for the prevention of haemodialysis catheter-related infections

BACKGROUND

Almost 30% of chronic haemodialysis (HD) patients are dependent on central venous catheters (CVCs) for their vascular access, and catheter-related bacteraemia (CRB) is the major reason for catheter loss and has been associated with substantial morbidity, including meta-static infections. This systematic review evaluates the benefits and harms of antimicrobial interventions for the prevention of catheter-related infections (CRIs).

METHODS

MEDLINE (1950-May 2009), EMBASE (1980-May 2009) CENTRAL (up to May 2009) and bibliographies of retrieved articles were searched for relevant RCTs. Analysis was by a random effects model and results expressed as rate ratio, relative risk (RR) and weighted mean difference (WMD) with 95% confidence intervals (CI).

RESULTS

A total of 29 trials with 2886 patients and 3005 catheters were included. Antimicrobial catheter locks (AMLs) significantly reduced the rates of CRBs (rate ratio, 0.33, 95% CI 0.24-0.45) and exit-site infections (ESIs) (rate ratio 0.67, 95% CI 0.47-0.96). Exit-site antimicrobial application also significantly reduced the rates of CRBs (rate ratio 0.21, 95% CI 0.12-0.36) and ESIs (rate ratio 0.22, 95% CI 0.10-0.47). Antimicrobial coating of HD catheters and the use of peri-operative antimicrobials did not result in significant reduction in rates of CRBs and ESIs.

CONCLUSION

The use of AMLs and exit-site antimicrobials are useful measures in the reduction of CRIs, whereas antimicrobial impregnated catheters and peri-operative systemic antimicrobial administration have not been found to be beneficial. Further head-to-head trials of various AMLs and exit-site antimicrobials are needed to know about their comparative clinical efficacy.

Eradication of microorganisms embedded in biofilm by an ethanol-based catheter lock solution

BACKGROUND

Interdialytic locking of catheters with antimicrobial agents is frequently used for preventing catheter-related infections, often associated with biofilm formation. We determined the bactericidal effect of 60% ethanol (ETOH) versus a 46.7% trisodium citrate (TSC) solution on biofilm embedded in silicone catheters.

METHODS

Four- and 24-h biofilms of Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans established in a microfermentor were exposed to ETOH and TSC for up to 24 h and the number of remaining viable microorganisms was determined.

RESULTS

ETOH 60% was significantly more effective than 46.7% TSC in rapidly eradicating sessile cells from all microorganisms tested. A 20-min ETOH 60% treatment completely eradicated the Gram-negative bacilli and C. albicans biofilms, which initially contained up to 10(8) and 10(5) cells, respectively. Gram-positive cocci biofilms only showed a significant 2.6-4.3 log reduction in the initial viable counts after 20 min of ETOH 60% treatment, with eradication occurring after 30 min. Confocal laser scanning microscopy observation of ETOH-treated biofilm showed sparse cells with respiratory activity. TSC 46.7% eradicated none of the tested microorganisms. In contrast, ETOH 60% totally eradicated planktonic cells, whereas TSC had significant bactericidal activity against K. pneumoniae, P. aeruginosa and C. albicans after 20 min, 1 and 24 h, respectively, but none on the Staphylococcus species.

CONCLUSIONS

This in vitro study demonstrates the superior antimicrobial activity of ETOH 60% in contrast to TSC 46.7% in eradicating biofilm formed on a silicon catheter. Hence, ethanol-based solution shows promise as a catheter lock solution.

Baseline characteristics of an incident haemodialysis population in Spain: results from ANSWER--a multicentre, prospective, observational cohort study

BACKGROUND

The ANSWER study aims to identify risk factors leading to increased cardiovascular morbidity and mortality in a Spanish incident haemodialysis population. This paper summarizes the baseline characteristics of this population.

METHODS

A prospective, observational, one-cohort study, including all consecutive incident haemodialysis patients from 147 Spanish nephrology services, was conducted. Patients were enrolled between October 2003 and September 2004. Sociodemographic, clinical, laboratory and health care characteristics were collected.

RESULTS

Baseline characteristics are described for 2341 incident haemodialysis patients [mean (SD) age 65.2 (14.5) years, 63% males]. The main cause of renal failure was diabetic nephropathy (26%). The majority of patients (57%) had a Karnofsky score of 80-100 and 27% were followed up by a nephrologist for 500 ng/ml, 41% and saturated transferrin <20 or >40%, 50%) despite previous treatment with erythropoiesis-stimulating agents in 41% of cases.

CONCLUSIONS

There is excessive use of temporary catheters and a high prevalence of uraemia-related cardiovascular risk factors among incident haemodialysis patients in Spain. The poor control of hypertension, anaemia, malnutrition and mineral metabolism and late referral to a nephrologist indicate the need for improving the therapeutic management of patients before the onset of haemodialysis.

Outcomes of Staphylococcus aureus infection in hemodialysis-dependent patients

BACKGROUND AND OBJECTIVES

Staphylococcus aureus is a leading cause of infection in patients with ESRD. Clinical and economic outcomes associated with S. aureus bacteremia and other S. aureus infections in patients with ESRD were examined.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Laboratory, clinical, and hospital billing data from a randomized trial of 3359 hemodialysis-dependent patients hospitalized with S. aureus infection in the United States whose vascular access type was fistula or graft and who were hospitalized with S. aureus infection to evaluate inpatient costs, hospital days, and mortality over 12 wk were used. Generalized linear regression was used to identify independent predictors of 12-wk costs, inpatient days, and mortality.

RESULTS

Of the 279 patients (8.3%) who developed S. aureus infection during approximately 1 yr of follow-up, 25.4% were treated as outpatients. Among patients for whom billing data were available, 89 patients hospitalized with S. aureus bacteremia incurred mean 12-wk inpatient costs of $19,454 and 11.9 inpatient days. Among the 70 patients hospitalized with non-bloodstream S. aureus infections, mean inpatient costs were $19,222 and the mean number of inpatient days was 11.3. Twelve-week mortality was 20.2 and 15.7% for patients with S. aureus bloodstream and non-bloodstream infections, respectively. Older age was independently associated with higher risk of death among patients with S. aureus bacteremia and with higher inpatient costs and more hospital days among patients with non-bloodstream infections.

CONCLUSIONS

Hemodialysis-dependent patients with fistula or graft access incur high costs and long inpatient stays when hospitalized for S. aureus infection.

Neointimal hyperplasia associated with synthetic hemodialysis grafts

Stenosis is a major cause of failure of hemodialysis vascular grafts and is primarily caused by neointimal hyperplasia (NH) at the anastomoses. The objective of this article is to provide a scientific review of the biology underlying this disorder and a critical review of the state-of-the-art investigational preventive strategies in order to stimulate further research in this exciting area. The histology of the NH shows myofibroblasts (that are probably derived from adventitial fibroblasts), extracellular matrices, pro-inflammatory cells including foreign-body giant cells, a variety of growth factors and cytokines, and neovasculature. The contributing factors of the pathogenesis of NH include surgical trauma, bioincompatibility of the synthetic graft, and the various mechanical stresses that result from luminal hypertension and compliance mismatch between the vessel wall and graft. These mechanical stimuli are focal in nature and may have a significant influence on the preferential localization of the NH. Novel mechanical graft designs and local drug delivery strategies show promise in animal models in preventing graft NH development. Successful prevention of graft stenosis would provide a superior alternative to the native fistula as hemodialysis vascular access.

Trisodium citrate 46.7% selectively and safely reduces staphylococcal catheter-related bacteraemia

BACKGROUND

Trisodium citrate (TSC) 30% has been shown in a randomized control trial to be an effective antimicrobial catheter locking solution, able to significantly reduce catheter-related bacteraemia (CRB) in haemodialysis patients. Since that report, the formulation in Europe has been changed to 46.7% TSC without confirmatory data on efficacy. We report a 55 915 patient-day at risk experience in tunnelled lines of 46.7% TSC, emphasizing efficacy and changes in microbiology seen.

METHODS

On 1 July 2006, inter-dialytic catheter locking solution was changed from 5000 IU/ml heparin to Citra-lock(TM) (46.7% TSC) in all haemodialysis patients at Barts and the London Renal Unit dialysing through an incident or prevalent tunnelled catheter. Prospectively collected blood culture data for the 6 months prior to the switch and 3 months at the end of the first year of TSC use were analysed. TSC tolerability was excellent with only a single withdrawal for intolerance of the agent. No major adverse events were reported.

RESULTS

A major fall in CRB rates was noticed with a change from heparin (2.13/1000 catheter-days) in 2006 to TSC (0.81/1000 catheter-days) in 2007. This was due to significant reductions in staphylococcal CRB, true for sensitive, methicillin-resistant and coagulase-negative staphylococci. No increase in catheter malfunction was observed.

CONCLUSIONS

We found that 46.7% TSC is a safe, convenient and highly effective catheter locking solution, leading to significant reduction in CRB largely by preventing staphylococcal bloodstream infections. Given that Staphylococcus aureus in particular is associated with serious and often disseminated infection, TSC seems to be a powerful tool for dialysis units.

Comparison of early versus late use of antibiotic locks in the treatment of catheter-related bacteremia

BACKGROUND AND OBJECTIVES

This retrospective study compared the effectiveness of the timing of the antibiotic locks to clear catheter-related bacteremia in children on chronic hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The early antibiotic lock group received antibiotic locks along with systemic antibiotics from the very beginning of catheter-related bacteremia. The late antibiotic lock group was given only systemic antibiotics initially, and antibiotic locks were used late in the infection if the catheter-related bacteremia could not be cleared after resolution of symptoms.

RESULTS

There were 264 catheter-related bacteremias in 79 children during 6 yr of observation. Early antibiotic locks were able to clear catheter-related bacteremia and resolve the symptoms more effectively without the need for catheter exchange when compared with late antibiotic locks. A total of 84 catheter-related bacteremias required wire-guided exchange of the catheters. Late antibiotic locks required wire-guided catheter exchange more frequently than the early antibiotic locks. The post-catheter-related bacteremia infection-free survival of the catheters after wire-guided exchange were significantly longer than those of both antibiotic lock groups. Recurrence of catheter-related bacteremia within 45 d after wire-guided exchange occurred at similar rates compared with the antibiotic lock groups.

CONCLUSION

Antibiotic locks are significantly more effective in clearing catheter-related bacteremia when used early in infection, diminishing the need for catheter exchange. Wire-guided exchange has a late-onset advantage for infection-free survival compared with catheter in situ treatment. The recurrence rates in the first 45 d after catheter-related bacteremia are similar regardless of the treatment strategy.

Comparison of tissue plasminogen activator-antibiotic locks with heparin-antibiotic locks in children with catheter-related bacteraemia

BACKGROUND

An accepted pathogenesis of catheter-related bacteraemia (CRB) is the seeding of microorganisms from the intraluminal biofilm of central venous catheters. Antibiotic locks (ABL) are solutions containing high concentrations of antimicrobials with or without anticoagulants that aim to destroy the biofilm.

METHODS

In this study, two different ABL solutions, tissue plasminogen activator (TPA)-based and heparin-based ABL, used in conjunction with systemic antibiotics, were prospectively compared in the treatment of CRB.

RESULTS

A total of 42 children on chronic haemodialysis with 11,016 catheter-days were observed for signs and symptoms of CRB over a period of 10 months. Twenty-four CRBs were diagnosed in 18 children (2.2 CRB/1000 catheter-days) and were treated with the protocol. Symptoms of CRB resolved in 83% within 48 h of treatment. None of the infected catheters required early emergent exchange or removal for poorly controlled CRB. Six children had recurrence of CRB within 6 weeks, of which four required catheter exchange. There was no specific microorganism or type of CRB that predisposed to higher recurrence rates. The mean infection-free survival of the catheters following TPA-ABL treatment was shorter than that following heparin-ABL treatment, but was not statistically significant by the log-rank test (126.8 +/- 81.6 days versus 154.5 +/- 70.4 days).

CONCLUSION

Both TPA-ABL and heparin-ABL used in conjunction with systemic antibiotics can effectively clear CRB without significant late recurrence at 6 weeks. Early use of ABL for management of CRB can potentially decrease the need for catheter removal, thus salvaging vascular access sites.

Influence of vascular access type on outcome measures in patients on maintenance hemodialysis

BACKGROUND

Previous studies postulate that end-stage renal disease (ESRD) patients dialyzed with central venous catheters (CVC) have poorer outcomes compared to patients using arteriovenous fistulae (AVF) or arteriovenous grafts (AVG). Clinical practice guidelines should obviate these differences if access was not important. This study compared clinical measures of adequacy, anemia, and nutrition/inflammation in prevalent hemodialysis patients in 2003 by access type.

METHODS

Data from The Renal Network Data System were analyzed by univariate analysis of variance to compare Kt/V, URR, albumin, hemoglobin (Hb) and recombinant human erythropoietin (EPO) dose by access type, while adjusting for pertinent factors.

RESULTS

12,501 patients were included. The access type distribution was AVF 36%, AVG 41%, and CVC 23%. CVC patients had lower mean URR, Kt/V, albumin concentration (p < 0.001) than other accesses. Serum Hbs were similar (p = 0.416), however EPO dose (U/kg/week) was higher in those dialyzed with CVC compared to AVF/AVG (p < 0.001).

CONCLUSIONS

Despite practice guidelines, patients dialyzed via CVC have poorer outcome measures compared to other accesses. This suggests that AVF should be used and/or appropriate adjustments need to be made for those dialyzed with CVC to achieve equal outcomes. Further studies defining barriers need to be conducted.

Comorbidities do not influence primary fistula success in incident hemodialysis patients: a prospective study

BACKGROUND AND OBJECTIVES

Concern about primary fistula failure may contribute to the underuse of arteriovenous fistula. The objective of this study was to investigate the baseline clinical parameters associated with primary fistula success.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Consecutive incident patients who commenced dialysis during a 28-mo period in a regional renal program were studied. Data on patient-related variables and on surgical approach (e.g., whether the surgeons routinely assess vessel size during the operation) were collected. Primary fistula success was defined as an arteriovenous fistula that was able to afford successful dialysis for 3 h with blood pump speed of > or =300 ml/min for three consecutive sessions.

RESULTS

A total of 205 (69%) patients had an AVF attempted as their first vascular access. The overall primary success rate was 64% and was similar for radiocephalic and brachiocephalic fistula. Logistic regression was done separately for patients with the two types of fistula because of the presence of statistical interaction. For radiocephalic fistula, male gender was the only parameter associated with primary fistula success (odds ratio 3.57; P = 0.01). The presence of comorbidity was not significantly associated with primary fistula failure.

CONCLUSIONS

Despite significant patient comorbidity, there was a high primary fistula success rate among this incident hemodialysis cohort. Given that vessel size may be the ultimate determinant of fistula success, if surgeons assess vessel size perioperatively, then the presence of significant comorbidity might not preclude arteriovenous fistula from being attempted as the initial access.

Prevention of sepsis during the transition to dialysis may improve the survival of transplant failure patients

Dialysis patients are at risk for sepsis, and the risk may be even higher among transplant failure patients because of previous or ongoing immunosuppression. The incidence and the consequences of sepsis as defined by International Classification of Diseases, Ninth Revision, Clinical Modification hospital discharge diagnoses codes were determined among 5117 patients who initiated dialysis after transplant failure between 1995 and 2004 in the United States. The overall sepsis rate was 11.8 per 100 patient years (95% confidence interval [CI] 11.5 to 12.1). Sepsis was highest in the first 6 mo after transplant failure (35.6 per 100 patient years [95% CI 29.4 to 43.0] between 0 to 3 mo after transplant failure; 19.7 per 100 patient years [95% CI 17.2 to 22.5] between 3 to 6 mo after transplant failure). In comparison, the sepsis rate among incident dialysis patients between 3 and 6 mo after dialysis initiation was 7.8 per 100 patient years (95% CI 7.3 to 8.3), whereas the sepsis rate among transplant recipients between 3 and 6 mo after transplantation was 5.4 per 100 patient years (95% CI 4.9 to 5.9). Patients who were > or =60 yr, obese patients, patients with diabetes, and patients with a history or peripheral vascular disease or congestive heart failure were at risk for sepsis. Transplant nephrectomy was not associated with septicemia. The role of continued immunosuppression and vascular access creation was not assessed and should be addressed in future studies. In a multivariate analysis, patients who were hospitalized for sepsis had an increased risk for death (hazard ratio 2.93; 95% CI 2.64 to 3.24; P < 0.001). Strategies to prevent sepsis during the transition from transplantation to dialysis may improve the survival of patients with allograft failure.

Major Difficulties the US Nephrologist Faces in Providing Adequate Dialysis

AIM

To identify the major difficulties nephrologists in the US face in providing adequate dialysis.

METHODS

To identify the perceived obstacles to achieving adequate dialysis in the US, 30 clinical support specialists responsible for nursing education and training were polled. Their responses together with those found in the recent literature were summarized and analyzed.

RESULTS

The obstacles identified fell into the following major categories: (1) economic; (2) personnel shortage; (3) education, and (4) cultural. The principal specific difficulties identified in providing adequate dialysis were the provision of sufficient time and frequency of dialysis, adequate volume control and vascular and peritoneal access.

CONCLUSIONS

The obstacles we currently face are serious but can be conquered through better understanding of the problems and education of professionals, patients and payers. The simple improvement in two specific areas, the creation of more native arteriovenous fistulae and growth of home dialysis, are identified as the highest priorities to overcome these obstacles.

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

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

Disease Management Improves End-Stage Renal Disease Outcomes

BACKGROUND/AIMS

Renal disease management organizations have reported achieving significant decreases in mortality and hospitalization in conjunction with cost savings, improved patient satisfaction and quality of life. Disease management organizations strive to fill existing gaps in care delivery through the standardized use of risk assessment, predictive modeling, evidence-based guidelines, and process and outcomes measurement. Patient self-management education and the provision of individual nurse care managers are also key program components.

METHODS

As we more fully measure clinical outcomes and total healthcare costs, including payments from all insurance and government entities, pharmacy costs and out of pocket expenditures, the full implications of disease management can be better defined.

RESULTS

The results of this analysis will have a profound influence on United States healthcare policy.

CONCLUSION

At present current data suggest that the promise of disease management, improved care at reduced cost, can and is being realized in end-stage renal disease.

Endovascular Treatment of the “Failing to Mature” Arteriovenous Fistula

In recent literature, surgically created hemodialysis (HD) arteriovenous fistulas (AVF) have high rates of primary failure. Endovascular treatment holds promise to salvage these fistulae. The outcomes of 119 patients who had a "failing to mature" AVF and presented for endovascular management were evaluated prospectively. All patients underwent a fistulogram. Stenotic lesions underwent balloon angioplasty, and accessory veins underwent obliteration. Technical success was determined immediately after the procedure. AVF salvage was determined by successful use during HD. Patients were followed up for 1 yr, during which primary and secondary AVF patency rates were measured. The distribution of stenoses was as follows: Artery, 6 (5.1%); arterial anastomosis, 56 (47.1%); juxta-arterial anastomosis, 76 (63.9%); peripheral vein, 70 (58.8%); and central vein, 10 (8.4%). Significant accessory veins were present in 35 (29.4%). Mixed lesions were found in 85 (71.4%). The technique was successful in 107 (89.9%), and the AVF was salvaged in 99 (83.2%). Follow-up of salvaged fistulae showed a total event rate of 0.38/access-year, thrombosis rate of 0.12/access-year, and loss rate of 0.04/access-year. Endovascular treatment of "failing to mature AVF" is safe and effective when performed in a dedicated center.