Use of vascular access for haemodialysis in Europe: a report from the ERA-EDTA Registry

Zero upper arm hemodialysis fistulas: utopian or realistic goal?

BACKGROUND

Although distal native fistula is the best first-line vascular access (VA), upper arm fistula (UAF) prevalence is increasing worldwide, except in Japan. Our previous survey on 50% of hemodialysis patients (HP) revealed a prevalence of UAF of less than 5%, which is lower than the findings published by the DOPPS 5 study in our country. We analyzed the VA prevalence on 100% of HPs from our department.

METHODS

In December 2021, we investigated the prevalence of vascular access of 1295 hemodialysis patients from 17 dialysis factories. VAs were classified according to location into distal forearm fistula (DFF), middle-proximal forearm fistula (MPFF), and UAF. The department manages VA using a Hub and Spoke model. The hub performs simple and complex VA including Graft placement, the Percutaneous Transluminal Angioplasty (PTA) of fistulas and central stenosis, and the surgical and endovascular rescue of thrombosed or stenotic fistulas. The spokes perform mainly simple DFFs.

RESULTS

The mean age of 1295 HP (35% females and 21% diabetics) was 69 ± 12.4 years; 506 (39%) were over 75 years old. The prevalence of DFF, MPFF, UAF, GRAFT, and CVC was 63.5%, 10.1%, 3%, 0.7%, and 22.5%, respectively. Data comparison between our two surveys revealed a lower MPFF, UAF, and GRAFT prevalence and increased CVC prevalence. Patients aged 75 years or older, women, and diabetics showed a higher frequency of CVC and a lower prevalence of DFF.

CONCLUSIONS

The findings confirm the low prevalence of UAF found in our prior survey, demonstrating that UAFs can be reduced to 5% or less, as seen in Japanese experience.

Risk of infections related to endovascular catheters and cardiac implantable devices in hemodialysis patients

Patients requiring dialysis are extremely vulnerable to infectious diseases. The high burden of comorbidities and weakened immune system due to uremia and previous immunosuppressive therapy expose the patient on dialysis to more infectious events than the general population. The infectious risk is further increased by the presence of endovascular catheters and implantable cardiologic devices. The former is generally placed as urgent vascular access for dialysis and in subjects requiring hemodialysis treatments without autogenous arteriovenous fistula. The high frequency of cardiovascular events also increases the likelihood of implanting indwelling implantable cardiac devices (CIED) such as pacemakers (PMs) and defibrillators (ICDs). The simultaneous presence of CVC and CIED yields an increased risk of developing severe prosthetic device-associated bloodstream infections often progressing to septicemia. Although, antibiotic therapy is the mainstay of prosthetic device-related infections, antibiotic resistance of biofilm-residing bacteria reduces the choice of infection eradication. In these cases, the resolution of the infection process relies on the removal of the prosthetic device. Compared to CVC removal, the extraction of leads is a more complex procedure and poses an increased risk of vessel tearing. As a result, the prevention of prosthetic device-related infection is of utmost importance in hemodialysis (HD) patients and relies principally on avoiding CVC as vascular access for HD and placement of a new class of wireless implantable medical devices. When the combination of CVC and CIED is inevitable, prevention of infection, mainly due translocation of skin bacteria, should be a mandatory priority for healthcare workers.

Sex-specific differences in a large cohort of Brazilian incident dialysis patients over 12 years: A retrospective study

OBJECTIVE

Sex-specific differences in the epidemiology of chronic kidney disease, such as higher prevalence of women on pre-dialysis and men on chronic dialysis treatment, have been reported worldwide. In this regard, data from non-high-income countries are scarce. We aimed to compare the demographic, clinical, and dialysis characteristics of incident dialysis patients, both men and women, in a large cohort of Brazilian patients over a 12-year period.

METHODS

This was a multicentric retrospective cohort study coordinated by the Brazilian Society of Nephrology. The study included all adult incident dialysis patients in the Brazilian Dialysis Registry from January 2011 to December 2022. The variables studied encompassed age, skin color, education, CKD etiology, predialysis nephrologist care, dialysis characteristics, and geographic region. Additionally, the sample was analyzed for each of the three 4-year periods over the 12 years of data collection.

RESULTS

A total of 24,632 incident dialysis patients were included. Men were 59.1% of the dialysis population, remaining stable over the three 4-year periods. Besides other differences, women started dialysis younger (58.5 ± 16.2 years vs 59.5 ± 14.4 years; p < 0.001), had a lower educational level (less than 8 years at school: 54% vs 44%; p < 0.001), received more predialysis nephrologist care (46.2% vs 44.2%; p = 0.04), and had a higher prevalence of peritoneal dialysis (4.4% vs 3.5%; p = 0.03).

CONCLUSION

We consistently observed a higher prevalence of men on dialysis and differences in demographic, clinical, and dialysis characteristics. The underlying reasons for these sex differences still necessitate further clarification.

A modified technique for arteriovenous fistula anastomosis: Preserving the surrounding tissue of the vein without the use of vascular clamps

BACKGROUND

This pilot study describes a new technique for creating an arteriovenous fistula (AVF) and presents the preliminary outcomes after 1 year of follow-up.

METHODS

The study included 19 patients (10 males, 9 females) with a mean age of 62 years (range 26-88 years). All patients received an AVF using a modified technique in which the surrounding tissues were not removed from the veins and no elastic loops or vascular clamps were used.

RESULTS

Immediate patency was obtained for all patients. The proportion of patients experiencing primary patency at 30 days and 6 months was 89.5% and 83.1%, respectively, and cumulative patency at 30 days and 6 months was 100%. At 1 year of follow-up, primary patency was 83.1% and cumulative patency was 100%.

CONCLUSIONS

Complete preservation of the surrounding venous tissue in the absence of vascular clamps successfully established AVF, with a high surgical success rate.

Definition and clinical management of haemodialysis central venous catheter local infections (exit site and tunnel infection): An international consensus assessment

AIM

To evaluate the relevance of signs and symptoms for the clinical identification of ESI and TI in HD-CVC, by means of international expert consensus, and to reach a consensus on a definition and clinical management (CM) for these infections.

BACKGROUND

A recent systematic review showed a high heterogeneity in the signs/symptoms used for determining exit site infection (ESI) and tunnel infection (TI) of haemodialysis central venous catheter (HD-CVC).

DESIGN

A modified Delphi ranking process was carried out between November 2020 and March 2021, consisting of four rounds using an online questionnaire with a panel of 26 experts from 12 countries.

METHODS

Experts responded on the level of relevance for the identification of ESI and TI, based on a list of 22 signs/symptoms obtained from a previous systematic review, using a 4-point Likert-type scale. After reaching consensus on the signs/symptoms, they followed the same method to reach consensus on the CM. The STROBE Checklist was used to report this study.

RESULTS

A high degree of consensus was reached to identify the presence of ESI based on nine signs/symptoms: presence of pain at the exit site (ES) during interdialysis period, with fever ≥38°C do not suspect other cause, local signs at the ES (inflammation, induration, swelling, hyperemia/erythema ≥2 cm from ES) and obvious abscess or purulent exudate at ES; and of TI. Likewise, 5 cm were agreed upon.

CONCLUSION

This Delphi study provides international expert consensus definitions of ESI and TI in HD-CVC, laying the groundwork for the validation of an HD-CVC ES clinical assessment scale for early identification of ESI.

RELEVANCE TO CLINICAL PRACTICE

In addition, this study provides a series of attitudes to consensual clinics regarding signs/symptoms of local infections in HD-CVC, which may be useful as expert opinion in clinical practice guidelines, when there is insufficient scientific evidence.

Autologous forearm arteriovenous loop vascular access, an option to be considered

BACKGROUND

Autologous arteriovenous fistula is usually the vascular access of choice for hemodialysis in patients with chronic kidney disease. Autologous forearm loops with cephalic or basilic vein are an alternative in those cases with a suitable forearm vein but with an unsuitable radial artery; however they are rarely used and there is little reported evidence of their usefulness. Our objective is to report our results on the creation of autogenous forearm loops as vascular access for hemodialysis.

METHODS

We present a prospective cohort study of autogenous forearm loop arteriovenous fistula created between 2010 and 2022, in patients with stage 4-5 chronic kidney disease. Demographic data, surgical details, vein used, follow up to 24 months, maturation, utilization, primary, assisted, and secondary patency estimations with Kaplan-Meier curves, as well as complications during follow-up, were recorded.

RESULTS

During the study period, 22 autologous forearm loops were created, 14 of them with cephalic, and 8 with basilic vein. Most (59%) of the patients were men, 19 were already on dialysis and the rest started during follow-up. Sixteen patients had previous vascular accesses. One patient was lost during follow-up. Six-week maturation rate was 61.9% and utilization rate was 57.1%. 6, 12, and 24 months primary and secondary patencies were 75.4%, 59.2%, 41.5% and 85.0%, 69.5%, 56.9% respectively. In five patients an access-induced distal ischemia was diagnosed, four successfully treated and only one patient lost the access. No cases of infection or other major complications were reported.

CONCLUSION

Autologous forearm loops have acceptable maturation (61.9%) and patency rates at follow-up (56.9% 2-years secondary patency). Although rarely used, they are a vascular access alternative that should be considered to preserve the proximal vasculature of the arm for future accesses.

Effect of kidney transplantation activity on arteriovenous fistula use in prevalent haemodialysis patients: A registry-based study

BACKGROUND

Kidney transplantation (KT) is considered to be the best kidney replacement therapy (KRT) option for most end-stage kidney disease (ESKD) patients. Arteriovenous fistula (AVF) is considered to be the best vascular access (VA) for most haemodialysis (HD) patients. In this study, we investigated the effect of KT activity on AVF use in prevalent HD patients. The probability of receiving a kidney graft (KTx) over time, depending on the first VA used to start the HD program, was also evaluated.

METHODS

Data from the Catalan Registry of prevalent patients on KRT by either KT or HD were examined over a 20-year period (1997-2017).

RESULTS

The percentage of prevalent ESKD patients with a functioning KTx increased from 40.5% in 1997 to 57.0% in 2017 and, conversely, the percentage of AVF utilisation in HD patients decreased from 86.0% to 63.2% during the same period (for both comparisons, p < 0.001). This inverse relationship was also demonstrated in other countries and regions worldwide by performing a simple linear regression analysis (R2 = 0.4974, p = 0.002). The probability of prevalent patients dialysed through an AVF in Catalonia was independently associated with the percentage of functioning KTx among KRT population, after adjusting by age, gender, primary kidney disease, time on KRT, cardiovascular disease and type of HD Unit. Incident patients starting HD through an AVF had a significantly higher probability of receiving a KTx over time in comparison to patients who initiated HD through a catheter (hazard ratio 1.68 [95% confidence interval: 1.41-2.00], p < 0.001).

CONCLUSIONS

In addition to some demographical and clinical characteristics of patients and type of HD Unit, KT activity can be a determining factor in AVF use in prevalent HD patients. Starting an HD programme through an AVF is independently associated with a greater probability of receiving a KTx as compared to starting HD through a catheter.

The impact of vascular access type on survival in haemodialysis: time for a paradigm shift? A prospective cohort study

INTRODUCTION

Although arteriovenous autologous fistula is the vascular access of choice due to better long-term outcome than central venous catheters, the use of central venous catheters is increasing. Our study aims to describe the survival and epidemiological features of a cohort of dialysis patients with a focus on the role of vascular access.

METHODS

Our study comprises a follow-up period from 2001 to 2020 in a single center. Descriptive analysis was performed on baseline data. Moreover, we analysed predictive variables of death with univariable and multivariable logistic regressions. Predictors of survival were analysed by univariable and multivariable Cox regression.

RESULTS

Our analysis includes 754 patients undergoing chronic haemodialysis. In the multivariable logistic regression, the use of tunnelled catheters resulted protective against death from any cause (Odds Ratio 0.43; p = 0.017). In the multivariable Cox analysis, being "late referral" was associated with decreased survival in the first 6 months since haemodialysis start (Hazard Ratio 3.79; p = 0.001). In the subgroup of elderly (age ≥ 75 years) patients (n = 201/472) with a follow up of 7-60 months, multivariable logistic regression showed that tunnelled catheters at the start of haemodialysis were associated with lower mortality (Odds Ratio, 0.25; p = 0.021), whereas vascular disease was found to be the main risk factor for death (Odds Ratio, 5.11; p = 0.000). Moreover, vascular disease was confirmed as the only independent risk factor by Cox analysis (Hazard Ratio, 1.58; p = 0.017).

CONCLUSIONS

In our cohort, mortality was found to be more closely associated with comorbidities than with the type of vascular access. Tunnelled central venous catheters might be a viable option for haemodialysis patients.

Stable incidence and survival of arteriovenous fistulas over 39 years: A long-term national cohort study

INTRODUCTION

The age and number of comorbidities in the hemodialysis population has increased over time. This may influence the construction and survival of the arteriovenous fistula (AVF). The present study explored the incidence and survival of AVFs over a period of 39 years.

METHODS

A retrospective cohort study was conducted based on Danish registries. Incident hemodialysis patients between 1977 and 2015 were included. The incidence of AVF and factors associated with the construction of an AVF were described. Risk factors for AVF survival and repair were explored by Kaplan Meier and Cox proportional hazard analysis.

RESULTS

The total number of arteriovenous accesses (AVF and arteriovenous grafts) were 10,187 and there were 4201 central venous catheters (CVC). No significant difference in the proportion of AVFs during the 39 years was seen. Age and renal diagnosis did not influence the proportion of AVFs. Patients with CVCs were found to have a significantly higher prevalence of comorbidities (p < 0.01). AVF survival remained stable during the 39 years. The first constructed AVF had the best survival, 35% still functioning after 15 years. Factors such as brachiocephalic AVF, female sex, and diabetic nephropathy increased the risk of AVF failure (Odds Ratio (OR): 2.46, 95% Confidence Interval (CI) (2.29-2.65), 1.17 (1.10-1.25), and 1.21 (1.12-1.3)), respectively.

CONCLUSION

Despite an older dialysis population, the proportion and survival of the AVF in the Danish dialysis population has not changed, probably because of increased awareness of AVF as the first choice of vascular access and improved surveillance, surgery, and repair.

Early identification of local infections in central venous catheters for hemodialysis: A systematic review

BACKGROUND

The use of central venous catheters (CVC) is associated with higher morbidity and mortality, related to infectious complications, contributing to poorer clinical outcomes and increased healthcare costs. According to the literature, the incidence of local infections related to CVC for hemodialysis is highly variable. This variability is related to differences in definitions of catheter-related infections.

OBJECTIVE

To identify signs and symptoms for determining local infections (exit site and tunnel tract infections) used in the literature in tunnelled and nontunnelled CVC for hemodialysis.

DESIGN

Systematic review METHODS: Structured electronic searches were conducted in five electronic databases, from 1 January 2000-31 August 2022, using key words and specific vocabulary, as well as manual searches in several journals. Additionally, vascular access clinical guidelines and infection control clinical guidelines were reviewed.

RESULTS

After validity analysis, we selected 40 studies and seven clinical guidelines. The definitions of exit site infection and tunnel infection used in the different studies were heterogeneous. Among the studies, seven (17,5 %) used the definitions of exit site and tunnel infection based on a clinical practice guideline. Three of the studies (7.5 %) used the Twardowski scale definition of exit site infection or a modification. The remaining 30 studies (75 %) used different combinations of signs and symptoms.

CONCLUSIONS

Definitions of local CVC infections are highly heterogeneous in the revised literature. It is necessary to establish a consensus regarding the definitions of hemodialysis CVC exit site and tunnel infections.

REGISTRATION

PROSPERO (CRD42022351097).

Report on an Italian survey of 72 stuck hemodialysis catheters

BACKGROUND

Reports of stuck hemodialysis catheters have been on the rise in recent years. Aim of this work is to report how this complication has been managed and the relative outcomes in a multicente Italian survey.

METHODS

Since 2012, the Italian Society of Nephrology (SIN) Project Group of Vascular Access has collected data among nephrologists on this complication. Data regarding 72 cases of stuck tunnelled central venous catheter (tCVC) in 72 patients were retrieved thanks to this survey.

RESULTS

In 11 patients (15%) the stuck catheter was directly buried or left in place. Sixty-one cases were managed through advanced removal techniques. Among these, 47 (77%) stuck tunnelled central venous catheters were successfully removed, while 14 (23%) failed to be withdrawn. Considering removed tCVCs, the use of endoluminal balloon dilatation alone or in combination with other tools showed a percentage of success of 88%. The removal procedure involved numerous specialists. Some complications occurred, such as breakage of the line or bleeding, and two cases of haemopericardium during an advanced procedure.

CONCLUSION

The survey shows how the stuck catheter complication was managed in different ways, with conflicting results. When utilized, endoluminal balloon dilatation proved to be the most effective and most often utilized technique, while some cases had suboptimal management or failure. This underlines how delicate the procedure is, and the need for both precise knowledge of this complication and timely organization of removal attempts.

Validity of a catheter exit site clinical assessment scale for the early detection of exit site infections in patients on haemodialysis with a central venous catheter: protocol for a multicentre validation study in Spain (EXITA Study)

INTRODUCTION

Haemodialysis patients with central venous catheter (HD-CVC) are at increased risk of exit site infections (ESIs) and catheter-related bloodstream infections, causing an increase of hospitalisation, morbidity and mortality rates. The main aim of the EXITA Study is to develop and validate an instrument for the early detection of HD-CVC ESIs.

METHODS AND ANALYSIS

EXITA is a multicentre prospective cohort study to validate the proposed instrument with a sample of 457 HD-CVCs: 92 in the ESI group and 365 in the non-ESI group. Sample size was calculated using Epidat V.4.2 software, with 95% and 90% expected sensitivity and specificity, respectively, an ESI incidence around 20% and 5%-10% precision range. During each haemodialysis session, the absence or presence of each item will be assessed by nurses. If any item is present, a microbiological study of pericatheter skin smears and/or exit site exudate will be carried out. HD-CVC ESI will be diagnosed when the pericatheter skin smears and/or exit site exudate culture are positive (≥15 CFU/mL by semiquantitative Maki's technique or ≥1000 CFU/mL by Cleri's technique). To validate the scale, a logistic regression analysis will be performed: the β coefficients of each of the signs/symptoms of the scale to be validated will be estimated. We will use logit function and calculate ESI probability=elogit ESI/1+elogit ESI.

ETHICS AND DISSEMINATION

The study has been approved by the Research Ethics Committee with Medical Products of Cantabria (approval code 2019.146). We will obtain informed consent from all participants before data collection. We will publish the study results in a peer-reviewed scientific journal.

Epidemiology of haemodialysis outcomes

Haemodialysis (HD) is the commonest form of kidney replacement therapy in the world, accounting for approximately 69% of all kidney replacement therapy and 89% of all dialysis. Over the last six decades since the inception of HD, dialysis technology and patient access to the therapy have advanced considerably, particularly in high-income countries. However, HD availability, accessibility, cost and outcomes vary widely across the world and, overall, the rates of impaired quality of life, morbidity and mortality are high. Cardiovascular disease affects more than two-thirds of people receiving HD, is the major cause of morbidity and accounts for almost 50% of mortality. In addition, patients on HD have high symptom loads and are often under considerable financial strain. Despite the many advances in HD technology and delivery systems that have been achieved since the treatment was first developed, poor outcomes among patients receiving HD remain a major public health concern. Understanding the epidemiology of HD outcomes, why they might vary across different populations and how they might be improved is therefore crucial, although this goal is hampered by the considerable heterogeneity in the monitoring and reporting of these outcomes across settings.

This Review examines the epidemiology of haemodialysis outcomes — clinical, patient-reported and surrogate outcomes — across world regions and populations, including vulnerable individuals. The authors also discuss the current status of monitoring and reporting of haemodialysis outcomes and potential strategies for improvement.

Nearly 4 million people in the world are living on kidney replacement therapy (KRT), and haemodialysis (HD) remains the commonest form of KRT, accounting for approximately 69% of all KRT and 89% of all dialysis.

Dialysis technology and patient access to KRT have advanced substantially since the 1960s, particularly in high-income countries. However, HD availability, accessibility, cost and outcomes continue to vary widely across countries, particularly among disadvantaged populations (including Indigenous peoples, women and people at the extremes of age).

Cardiovascular disease affects over two-thirds of people receiving HD, is the major cause of morbidity and accounts for almost 50% of mortality; mortality among patients on HD is significantly higher than that of their counterparts in the general population, and treated kidney failure has a higher mortality than many types of cancer. Patients on HD also experience high burdens of symptoms, poor quality of life and financial difficulties.

Careful monitoring of the outcomes of patients on HD is essential to develop effective strategies for risk reduction. Outcome measures are highly variable across regions, countries, centres and segments of the population. Establishing kidney registries that collect a variety of clinical and patient-reported outcomes using harmonized definitions is therefore crucial.

Evaluation of HD outcomes should include the impact on family and friends, and personal finances, and should examine inequities in disadvantaged populations, who comprise a large proportion of the HD population.

A modified no-touch technique for anastomosis to create a radiocephalic arteriovenous fistula

The application of a no-touch technique to create an autologous radiocephalic arteriovenous fistula might improve the patency rate. In the present report, we have expanded the concept of the no-touch technique by introducing a modified no-touch technique in which we preserve the perivenous vascular tissue, followed by a functional end-to-side anastomosis to create a radiocephalic arteriovenous fistula with early maturation for hemodialysis.

Initial Clinical Experience with a Symmetric Tip Tunneled Hemodialysis Catheter Without Side Holes

The purpose of this article is to assess the performance and safety of a novel, symmetric, side-hole-free tunneled cuffed catheter hypothesized to sustain adequate flow without the need for side holes. Between November 2016 and January 2019, Pristine hemodialysis catheters were placed de novo in 45 end-stage renal disease patients (27 males and 18 females) at a single investigational site. Forty-one catheters were placed in the right and four in the left internal jugular vein. There were no incidents of insertion failure. Patients had dialysis three times per week and were followed at four investigational sites. Nominal catheter flows, incidence of poor flow, and catheter-related infections were recorded at each dialysis session and analyzed. The average follow-up time was 161.69 days for a total of 7116 catheter days. Nine patients died from reasons unrelated to the catheter and one patient switched to fistula. Four patients had poor flows necessitating catheter replacement. Four patients had catheter-related bloodstream infections which resolved with antibiotics. These equate to 0.56 events per 1000 catheter days. Catheter survival was 100%, 97.6%, and 89.7% at 30, 90, and 180 days, respectively. The initial clinical assessment of the symmetric Pristine hemodialysis catheter featuring a Y-tip devoid of side holes revealed good catheter performance and survival and a low complication rate.

Influence of Tunneled Hemodialysis-Catheters on Inflammation and Mortality in Dialyzed Patients

Older age and comorbidities in hemodialysis patients determines the use of tunneled catheters as vascular access despite their reported clinical and mortality disadvantages. This prospective matched study analyzes the impact of permanent catheters on inflammation and mortality in hemodialysis patients; We studied 108 patients, 54 with AV-fistula (AVF) and 54 with indwelling hemodialysis catheters (HDC) matched by sex, age, diabetes and time under renal-replacement therapy comparing dialysis efficacy, inflammation and micro-inflammation parameters as well as mortality. Cox-regression analysis was applied to determine predictors of mortality, HDC patients presented higher C-reactive-protein (CRP) blood levels and percentage of pro-inflammatory lymphocytes CD14+/CD16+ with worse dialysis-efficacy parameters. Thirty-six-months mortality appeared higher in the HDC group although statistical significance was not reached. Age with a Hazard Ratio (HR) = 1.06, hypoalbuminemia (HR = 0.43), hypophosphatemia (HR = 0.75) and the increase in CD14+/CD16+ monocyte count (HR = 1.02) were predictors of mortality; elder patients dialyzing through HDC show increased inflammation parameters as compared with nAVF bearing patients, although they do not present a significant increase in mortality when matched by covariates. Increasing age and percentage of pro-inflammatory monocytes as well as decreased phosphate and serum-albumin were predictors of mortality and indicate the main conclusions or interpretations.

Association of glomerular filtration rate slope with timely creation of vascular access in incident hemodialysis

The factors associated with the timely creation of distal vascular access for hemodialysis initiation are unclear. We aimed to explore the association between the slope of estimated glomerular filtration rate (eGFR) and the successful usage of vascular access upon hemodialysis initiation. This single center retrospective cohort study enrolled chronic kidney disease patients who undertook a multidisciplinary care program from 2003 to 2016. Using eGFR slope as predictor, we evaluated the vascular access created timely upon hemodialysis initiation. Among the 987 patients, vascular access was created at a median eGFR of 5.8 min/ml/1.73 m², with a median duration of 3.1 months before hemodialysis. The proportions of vascular access created timely, created not timely (vascular access immature), and not created were 68.5%, 8.8%, and 22.7%, respectively. There was a significant negative association of eGFR upon vascular access creation with eGFR slope (r = − 0.182, P < 0.001). The fastest eGFR slope patients (the first quartile or < − 10 min/ml/1.73 m²/year) had the lowest percentage of vascular access created timely. In the multivariable logistic regression analysis, only higher eGFR upon vascular access creation (P = 0.001) and eGFR slope (P = 0.009) were significantly associated with vascular access created timely. The adjusted odds ratios of each quartile of eGFR slopes for vascular access created timely were 0.46 (95% confidence interval 0.27–0.86), 1.30 (0.62, 2.72), 1.00 (reference), and 0.95 (0.48–1.87), respectively. eGFR slope is associated with the timely creation of vascular access for the initiation of hemodialysis in a reverse-J-shaped pattern and may help determine the time of vascular access creation.

Prevention of tunneled cuffed catheter dysfunction with prophylactic use of a taurolidine urokinase lock: A randomized double-blind trial

Background

The efficacy and cost-effectiveness of prophylactic thrombolytic locks in hemodialysis patients at high-risk of thrombotic dialysis catheter dysfunction is uncertain. We investigated this question in a double-blinded randomized controlled study.

Methods

Prevalent hemodialysis patients from 8 Belgian hemodialysis units, with ≥2 separate episodes of thrombotic dysfunction of their tunneled cuffed catheter during the 6 months before inclusion, were randomized to either: taurolidine heparin locks thrice weekly (control arm) or the same locks twice a week combined with taurolidine urokinase locks once a week before the longest interval without HD (TaurolockU arm). The primary efficacy outcome was the incidence rate of catheter thrombotic dysfunction requiring thrombolytic locks to restore function.

Results

68 hemodialysis patients (32 controls, 36 urokinase) were followed during 9875 catheter days between May 2015 and June 2017. Incidence rate of thrombotic catheter dysfunction was 4.8 in TaurolockU vs 12.1/1000 catheter days in control group (rate ratio 0.39; 95%CI 0.23–0.64). 15/36 (42%) catheters in the treatment group required at least one therapeutic urokinase lock vs 23/32 (72%) in the control group (P = 0.012). The two groups did not differ significantly in catheter-related bloodstream infection and combined cost of prophylactic and therapeutic catheter locks. The TaurolockU group had a numerically higher number of episodes of refractory thrombosis.

Conclusions

Prophylactic use of urokinase locks is highly effective in reducing the number of thrombotic catheter dysfunctions in catheters with a history of recurring dysfunction. Prophylactic use of urokinase locks did not reduce the overall costs associated with catheter locks and was associated with a numerically higher number of episodes of refractory thrombosis.

Trial registration

ClinicalTrials.gov Identifier: NCT02036255.

Substitution of citrate with tissue plasminogen activator (rt-PA) for catheter lock does not improve patency of tunnelled haemodialysis catheters in a randomised trial

Backround

The study aim was to establish if substitution of citrate with rt-PA for catheter lock once weekly can reduce the incidence of catheter-related blood stream infections (CR-BSI) or improve patency of tunneled haemodialysis catheters.

Methods

All incident patients undergoing insertion of a tunneled haemodialysis catheter were screened and included except those suffering infection or using oral anticoagulation. Study participants were randomized into two arms according to the solution applied as catheter lock: receiving either trisodium citrate (Citra-LockTM 4%) only or rt-PA (Actilyse® 1 mg/ml) on the middle session each week with citrate used on the first and third sessions. The incidence of CR-BSI (confirmed by positive blood culture), catheter non-function (complete obstruction), and malfunction (blood flow < 250 ml/min) was recorded. Statistical significance was tested with ANOVA, post hoc analysis was performed by means of multiple linear regression.

Results

Totally, 18 patients were included and followed during 655 haemodialysis sessions. No episode of CR-BSI was detected while 6 catheter non-functions (0.9% sessions) and 101 malfunctions (15.4% sessions) were recorded. The incidence of both events was equal between the study arms: 4 non-functions and 55 malfunctions in the rt-PA arm and 2 non-functions and 46 malfunctions in the citrate arm (p = 0.47 and p = 0.24, respectively). Additionally, the mean blood flow achieved did not differ significantly between the arms: 326 ± 1,8 and 326 ± 1,9 ml/min (p = 0.95) in rt-PA and citrate arms, respectively. Post hoc analysis identified time elapsed since previous session (β = 0.12, p = 0.005) and malfunction on previous session (β = 0.25, p < 0.001) as significant factors affecting the occurrence of malfunction. By contrast, the study arm, rt-PA application on previous session, and catheter vintage did not enter the model.

Conclusion

Substitution of citrate with rt-PA for catheter lock does not reduce the incidence of catheter malfunction neither does it affect the blood flow achieved during haemodialysis. Catheter patency is related rather to the time interval between sessions and to previous malfunction (thus probably reflecting undefined individual factors). The incidence of CR-BSI within pre-selected haemodialysis population is sporadic (less than 1 per 4.3 patient years in our sample).

Trial registration

Australian New Zealand Clinical Trials Registry, ACTRN12612000152820. Retrospectively registered 03/02/2012.

Clot accumulation at the tip of hemodialysis catheters in a large animal model

Background:

The issue of side holes in the tips of the tunneled cuffed central venous catheters is complex and has been subject to longstanding debate. This study sought to compare the clotting potential of the side-hole-free Pristine hemodialysis catheter with that of a symmetric catheter with side holes.

Methods:

Both jugular veins of five goats were catheterized with the two different catheters. The catheters were left in place for 4 weeks and were flushed and locked with heparin thrice weekly. The aspirated intraluminal clot length was assessed visually prior to each flushing. In addition, the size and weight of the clot were recorded upon catheter extraction at the end of the 4-week follow-up

Results:

The mean intraluminal clot length observed during the entire study follow-up measured up to a mean of 0.66 cm in the GlidePath (95% CI, 0.14–1.18) and 0.19 cm in the Pristine hemodialysis catheter (95% CI, −0.33 to 0.71), the difference being statistically significant (p = 0.026). On average, 0.01 g and 0.07 g of intraluminal clot were retrieved from the Pristine and GlidePath catheters, respectively (p = 0.052).

Conclusion:

The Pristine hemodialysis catheter was largely superior to a standard side hole catheter in impeding clot formation, and, contrary to the side hole catheter, allowed for complete aspiration of the intraluminal clot.

Sex differences in the vascular access of hemodialysis patients: a cohort study

Background

We describe differences for probability of receiving a fistula attempt, achieving fistula use, remaining catheter-free and the rate of access-related procedures as a function of sex.

Methods

Prospectively collected vascular access data on incident dialysis patients from five Canadian programs using the Dialysis Measurement Analysis and Reporting System to determine differences in fistula-related outcomes between women and men. The probability of receiving a fistula attempt and the probability of fistula use were determined using binary logistic regression. Catheter and fistula procedure rates were described using Poisson regression. We studied time to fistula attempt and time to fistula use, accounting for competing risks.

Results

We included 1446 (61%) men and 929 (39%) women. Men had a lower body mass index (P < 0.001) and were more likely to have coronary artery disease (P < 0.001) and peripheral vascular disease (p < 0.001). A total of 688 (48%) men and 403 (43%) women received a fistula attempt. Women were less likely to receive a fistula attempt by 6 months {odds ratio [OR] 0.64 [95% confidence interval (CI) 0.52-0.79]} and to achieve catheter-free use of their fistula by 1 year [OR 0.38 (95% CI 0.27-0.53)]. At an average of 2.30 access procedures per person-year, there is no difference between women and men [incidence rate ratio (IRR) 0.97 (95% CI 0.87-1.07)]. Restricting to those with a fistula attempt, women received more procedures [IRR 1.16 (95% CI 1.04-1.30)] attributed to increased catheter procedures [IRR 1.50 (95% CI 1.27-1.78)]. There was no difference in fistula procedures [IRR women versus men 0.96 (95% CI 0.85-1.07)].

Conclusion

Compared with men, fewer women undergo a fistula attempt. This disparity increases after adjusting for comorbidities. Women have the same number of fistula procedures as men but are less likely to successfully use their fistula.

Vascular access type and mortality in haemodialysis: a retrospective cohort study

Background

Haemodialysis patients have a high mortality rate. Part of this can be attributed to vascular access complications. Large retrospective studies have shown a higher mortality in patients dialysed with a catheter, which is mostly ascribed to infectious complications. Since we observe very little infectious complications in our haemodialysis patients, the aim of our study was to assess if we could still detect a difference in survival according to vascular access type.

Methods

Patients that started chronic haemodialysis treatment between 1/1/2007 and 31/12/2016 at the ‘Universitair Ziekenhuis Brussel’ were retrospectively studied. The time to death was studied as a function of the two main vascular access types using survival analysis, considering the type of vascular access at the initiation of dialysis or as time varying, and accounting for the available baseline characteristics.

Results

Of 374 patients 309 (82.6%) initiated haemodialysis with a catheter, while 65 patients initiated with an arteriovenous access. Vascular access type during follow-up did not change in 74% of all patients. A Kaplan Meier plot did not suggest a survival dependent on the vascular access type at start. An extended cox proportional hazard analysis showed that vascular access type was not independently correlated with mortality. However, age, history of congestive heart failure and active cancer at initiation of dialysis were independently associated with mortality.

Conclusions

In this retrospective cohort study, haemodialysis vascular access type was not independently correlated with patient survival, even after taking into account change of vascular access over time.

Vascular access as a survival factor for the hemodialysis population: a retrospective study

BACKGROUND

The creation of vascular access is an essential condition for providing hemodialysis, which remains the only option for most patients suffering from end-stage renal disease. Selection of the type of vascular access affects patients' clinical outcomes, access maintenance frequency, risk of infection and major adverse cardiac events during dialysis. To improve the decision-making process, we performed a retrospective clinical data analysis of dialyzed patients and critically compared the survival rates between two types of vascular access applied during dialysis therapy during a 5 years follow-up period.

METHODS

Using nationally representative data from 18 dialysis centers across Slovakia, we explore and compare survival rates of 960 adult patients undergoing hemodialysis using either a central venous catheter (CVC) or an arteriovenous fistula (AVF). Length of dialysis, protein malnutrition and comorbidities were examined as possible covariates that might influence survival rates.

RESULTS

Chances of surviving for a one-year period were higher by 52% in AVF patients compared to CVC patients (HR 1.52; 95% CI 1.27-1.83; P<0.001) regardless of age, sex, nutritional status, time spent on dialysis and comorbidities. The presence of cardiac congestion (HR 1.26 [95% CI 1.06-1.50], P<0.01) and malnutrition (protein malnutrition: HR 0.98 [95% CI 0.96-1.00], P<0.05; lean tissue index: HR 0.79 [95% CI 0.67-0.93], P<0.01) decreases chances for survival.

CONCLUSIONS

A functional arteriovenous fistula is a significant predictor of survival in the population dependent on hemodialysis, independently of sociodemographic parameters and serious comorbidities. Therefore, if various types of vascular accesses are applicable for the patient, AVF should be prioritized over CVC.

The effects of vascular access types on the survival and quality of life and depression in the incident hemodialysis patients

Background

Although arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis (HD), the association between vascular access types and quality of life is not well-known. We investigated the relationships between HD vascular access types and all-cause mortality, health-related quality of life (HRQOL) and the degree of depression in a large prospective cohort.

Methods

A total of 1461 patients who newly initiated HD were included. The initial vascular access types were classified into AVF, arteriovenous graft (AVG), and central venous catheter (CVC). The primary outcomes were all-cause mortality and HRQOL and depression. The secondary outcome was all-cause hospitalization. Kidney Disease Quality of Life Short Form 36 (KDQOL-36) and Beck’s depression inventory (BDI) scores were measured to assess HRQOL and depression.

Results

Among 1461 patients, we identified 314 patients who started HD via AVF, 76 via AVG, and 1071 via CVC. In the survival analysis, patients with AVF showed significantly better survival compared with patients with other accesses (p < .001). The AVF and AVG group had higher KDQOL-36 score and lower BDI score than CVC group at 3 months and 12 months after the initiation of HD. The frequency of hospitalization was higher in patients with AVG compared to those with AVF (AVF 0.7 vs. AVG 1.1 times per year) (p = .024).

Conclusions

The patients with AVF had better survival rate and low hospitalization rate, and the patients with AVF or AVG showed both higher HRQOL and lower depression scores than those with CVC.

Non-invasive tunnelled catheter reposition (NTCR): A simple and safe method to restore central tunnelled catheter function for haemodialysis

Despite all efforts, still many end-stage kidney disease (ESKD) patients are dialysed using a central tunnelled catheter (CTC) as vascular access. When the CTC blood flow becomes ineffective, a number of protocols are advised. However, all of them are time- and cost-consuming. The manoeuvre of a non-invasive tunnelled catheter reposition (NTCR) was introduced to restore the CTC function. NTCR was based on gentle movements of the CTC, with or without a simultaneous flushing of the CTC lines, which resulted in a quick reposition of the CTC tip. This study comprises the analysis of a total of 297 NTCRs, which were performed in 114 patients, thus enabling an effective blood flow after 133 procedures (44.7%).Partially effective blood flow followed 123 procedures (41.4%), and it failed altogether in 41 cases (13.9%). Overall, 86% of conducted NTCRs improved the CTC patency to perform a haemodialysis session. The procedure could be successfully repeated, with a similar result after the first and the second attempt. Complications were observed only after 3.4% of all interventions. The novel NTCR manoeuvre was safe and effective in the majority of the CTC dysfunction episodes. It seemed to reduce fibrinolytic usage, allowed an immediate haemodialysis session commencement, therefore, it might save both the costs and the nursing staff time.

The benefit of early survival on PD versus HD—Why this is (still) very important

There are a number of misconceptions around the identified early survival benefit of peritoneal dialysis (PD) relative to hemodialysis (HD), including that such benefits “even out in the end” since the relative risk of death over time eventually encompasses 1.0 (or even an estimate that is unfavorable to PD); that the early benefit is, in fact, most likely due to unmeasured confounding; and such benefits are only due to the influence of central venous catheters and “crash starters” in the HD group. In fact, the early survival benefit results in a substantial gain of patient life years in PD cohorts relative to HD ones, even if it the benefit appears to “even out in the end,” is relatively insensitive to unmeasured confounding, and persists even when the effects of central venous catheters are accounted for. In this review, the calculations and arguments are made to support these tenets. Survival on dialysis is still one of the most important considerations for all stakeholders in the end-stage kidney disease community, including patients who rank it among their top priorities. Shared decision-making is a fundamental patient right and requires both balanced information and an iterative mechanism for a consensual decision based on shared understanding and purpose. A cornerstone of this process should be an explicit discussion of the early survival benefit of PD relative to HD.

Computational study on the haemodynamic and mechanical performance of electrospun polyurethane dialysis grafts

Compliance mismatch between an arteriovenous dialysis graft (AVG) and the connected vein is believed to result in disturbed haemodynamics around the graft–vein anastomosis and increased mechanical loading of the vein. Both phenomena are associated with neointimal hyperplasia development, which is the main reason for AVG patency loss. In this study, we use a patient-specific fluid structure interaction AVG model to assess whether AVG haemodynamics and mechanical loading can be optimised by using novel electrospun polyurethane (ePU) grafts, since their compliance can be better tuned to match that of the native veins, compared to gold standard, expanded polytetrafluoroethylene (ePTFE) grafts. It was observed that the magnitude of flow disturbances in the vein and the size of anastomotic areas exposed to highly oscillatory shear (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {OSI} >0.25$$\end{document}OSI>0.25) and very high wall shear stress (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$>40 \hbox { Pa}$$\end{document}>40Pa) were largest for the ePTFE graft. Median strain and von Mises stress in the vein were similar for both graft types, whereas highest stress and strain were observed in the anastomosis of the ePU graft. Since haemodynamics were most favourable for the ePU graft simulation, AVG longevity might be improved by the use of ePU grafts.

High success rate in salvage of catheter-related bloodstream infections due to Staphylococcus aureus, on behalf of project group of Italian society of nephrology

BACKGROUND

Catheter-related bloodstream infections caused by Staphylococcus aureus represent one of the most fearful infections in chronic haemodialysis patients with tunnelled central venous catheters. Current guidelines suggest prompt catheter removal in patients with positive blood cultures for S. aureus. This manoeuvre requires inserting a new catheter into the same vein or another one and is not without its risks.

METHODS

A protocol based on early, prompt diagnosis and treatment has been utilized in our renal unit since 2012 in an attempt to salvage infected tunnelled central venous catheters. We prospectively observed 247 tunnelled central venous catheters in 173 haemodialysis patients involving 167,511 catheter days.

RESULTS

We identified 113 catheter-related bloodstream infections (0.67 episodes per 1000 days/tunnelled central venous catheter). Forty were caused by S. aureus, including 19 by methicillin-resistant S. aureus (79% saved) and 21 by methicillin-sensitive S. aureus (90% saved), of which 34 (85%) were treated successfully. Eight recurrences occurred and six (75%) were successfully treated. A greater than 12 h time to blood culture positivity for S. aureus was a good prognostic index for successful therapy and tunnelled central venous catheter rescue.

CONCLUSION

Our data lead us to believe that it is possible to successfully treat catheter-related bloodstream infection caused by S. aureus and to avoid removing the tunnelled central venous catheter in many more cases than what has been reported in the literature. On the third day, it is mandatory to decide whether to replace the tunnelled central venous catheter or to carry on with antibiotic therapy. Apyrexia and amelioration of laboratory parameters suggest continuing systemic and antibiotic lock therapy for no less than 4 weeks, otherwise, tunnelled central venous catheter removal is recommended.

Influence of gender and age on haemodialysis practices: a European multicentre analysis

Background

Women of all ages and elderly patients of both genders comprise an increasing proportion of the haemodialysis population. Worldwide, significant differences in practice patterns and treatment results exist between genders and among younger versus older patients. Although efforts to mitigate sex-based differences have been attempted, significant disparities still exist.

Methods

This retrospective cohort study included all 1247 prevalent haemodialysis patients in DaVita units in Portugal (five dialysis centres, n = 730) and Poland (seven centres, n = 517). Demographic data, dialysis practice patterns, vascular access prevalence and the achievement of a variety of Kidney Disease: Improving Global Outcomes (KDIGO) treatment targets were evaluated in relation to gender and age groups.

Results

Body weight and the prescribed dialysis blood flow rate were lower in women (P < 0.001), whereas treated blood volume per kilogram per session was higher (P < 0.01), resulting in higher single-pool Kt/V in women than in men (P < 0.001). Haemoglobin was significantly higher in men (P = 0.01), but the proportion of patients within target range (10–12 g/dL) was similar. Men more often had an arteriovenous fistula than women (80% versus 73%; P < 0.01) with a similar percentage of central venous catheters. There were no gender-specific differences in terms of dialysis adequacy, anaemia parameters or mineral and bone disorder parameters, or in the attainment of KDIGO targets between women and men >80 years of age.

Conclusions

This large, multicentre real-world analysis indicates that haemodialysis practices and treatment targets are similar for women and men, including the most elderly, in DaVita haemodialysis clinics in Europe.

Evaluation of the efficacy of an interdialytic "ethanol 40% v/v - enoxaparin 1000 U/mL" lock solution to prevent tunnelled catheter infections in chronic hemodialysis patients: a multi-centre, randomized, single blind, parallel group study

BACKGROUND

Tunnelled dialysis catheter (TC) infections are a major health complication and are associated with increased antibiotic consumption, hospital stays, health costs and mortality. Experimental data provide evidence that Ethenox, a mixture of enoxaparine 1000 U/mL in 40% v/v ethanol, could be a promising lock solution. The aim of the study is to compare an interdialytic lock solution of Ethenox with reference lock solutions, unfractionated heparin (UFH) or citrate 4% for the prevention of TCI in hemodialysis patients.

METHOD

This study will monitor a multicentre, prospective, single blind, randomized, controlled, parallel group trial. The main inclusion criteria are patients > 18 years old with end-stage renal disease, treated with chronic hemodialysis/hemodiafiltration three times a week, with incident or prevalent non-impregnated internal jugular TCs inserted for at least 2 weeks and able to give informed consent. Exclusion criteria are TCI in the previous 4 weeks and anti-infective treatment for TCI in the previous 2 weeks. Patients will be randomized to receive either study treatment Ethenox in the intervention group or reference solutions in the control group, unfractionated heparin (UFH) or citrate 4% w/v according to usual practice. The primary outcome measure will be time to first TCIs assessed by an endpoint adjudication committee blinded to the study arm according to predefined criteria. Patients will receive the study treatment for up to 12 months. Intention-to-treat analysis of the primary endpoint will be performed with a marginal Cox proportional hazard model. Prospective power calculations indicate that the study will have 90% statistical power to detect a clinical significant two-fold increase in median infection-free survival if 200 patients are recruited into each arm over a period of 24 months.

DISCUSSION

Firm evidence of the efficacy of the Ethenox lock in preventing TCI could be of major clinical benefit for patients. The results of this study will allow the development of new guidelines based on a high level of evidence.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03083184 , date of registration March 17 2017 and European Clinical Trials Database Identifier: EudraCT 2016-A00180-51), date of registration July 11 2016.

Hemodialysis vascular access and subsequent transplantation: a report from the ESPN/ERA-EDTA Registry

BACKGROUND

Current guidelines advocate use of arteriovenous fistula (AVF) over central venous catheter (CVC) for children starting hemodialysis (HD). European data on current practice, determinants of access choice and switches, patient survival, and access to transplantation are limited.

METHODS

We included incident patients from 18 European countries who started HD from 2000 to 2013 for whom vascular access type was reported to the ESPN/ERA-EDTA Registry. Data were evaluated using descriptive statistics, logistic and Cox regression models, and cumulative incidence competing risk analysis.

RESULTS

Three hundred ninety-three (55.1%) of 713 children started HD with a CVC and were more often females, younger, had more often an unknown diagnosis, glomerulonephritis, or vasculitis, and lower hemoglobin and height-SDS at HD initiation. AVF patients were 91% less likely to switch to a second access, and two-year patient survival was 99.6% (CVC, 97.2%). Children who started with an AVF were less likely to receive a living donor transplant (adjusted HR, 0.30; 95% CI, 0.16-0.54) and more likely to receive a deceased donor transplant (adjusted HR, 1.50; 95% CI, 1.17-1.93), even after excluding patients who died or were transplanted in the first 6 months.

CONCLUSIONS

CVC remains the most frequent type of vascular access in European children commencing HD. Our results suggest that the choice for CVC is influenced by the time of referral, rapid onset of end-stage renal disease, young age, and an expected short time to transplantation. The role of vascular access type on the pattern between living and deceased donation in subsequent transplantation requires further study.

Precurved non-tunnelled catheters for haemodialysis are comparable in terms of infections and malfunction as compared to tunnelled catheters: A retrospective cohort study

Background:

The main limitations of central venous catheters for haemodialysis access are infections and catheter malfunction. Our objective was to assess whether precurved non-tunnelled central venous catheters are comparable to tunnelled central venous catheters in terms of infection and catheter malfunction and to assess whether precurved non-tunnelled catheters are superior to straight catheters.

Materials and methods:

In this retrospective, observational cohort study, adult patients in whom a central venous catheter for haemodialysis was inserted between 2012 and 2016 were included. The primary endpoint was a combined endpoint consisting of the first occurrence of either an infection or catheter malfunction. The secondary endpoint was a combined endpoint of the removal of the central venous catheter due to either an infection or a catheter malfunction. Using multivariable analysis, cause-specific hazard ratios for endpoints were calculated for tunnelled catheter versus precurved non-tunnelled catheter, tunnelled catheter versus non-tunnelled catheter, and precurved versus straight non-tunnelled catheter.

Results:

A total of 1603 patients were included. No difference in reaching the primary endpoint was seen between tunnelled catheters, compared to precurved non-tunnelled catheters (hazard ratio, 0.91; 95% confidence interval, 0.70–1.19, p = 0.48). Tunnelled catheters were removed less often, compared to precurved non-tunnelled catheters (hazard ratio, 0.65; 95% confidence interval, 0.46–0.93; p = 0.02). A trend for less infections and catheter malfunctions was seen in precurved jugular non-tunnelled catheters compared to straight non-tunnelled catheters (hazard ratio, 0.60; 95% confidence interval, 0.24–1.50; p = 0.28) and were removed less often (hazard ratio, 0.41; 95% confidence interval, 0.18–0.93; p = 0.03).

Conclusion:

Tunnelled central venous catheters and precurved non-tunnelled central venous catheters showed no difference in reaching the combined endpoint of catheter-related infections and catheter malfunction. Tunnelled catheters get removed less often because of infection/malfunction than precurved non-tunnelled catheters.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

How arteriovenous grafts could help to optimize vascular access management

A one-size-fits-all approach to vascular access for dialysis may be prejudicial. Arteriovenous fistulae (AVF) have high primary failure, failure to mature rate, and late-stage complications making them unsuitable choice for many patients. Aging of population with chronic kidney disease (CKD) coupled with venous injury during CKD stages depletes suitable superficial veins for AVF creation. The National Institutes of Health consortium demonstrated the difficulty in attaining a functional AVF in hemodialysis patients. Recognition of flaws in AVF and the quest to reduce catheter use bring to the fore the benefits of arteriovenous grafts (AVG). Advances in catheter technologies, flow, care, and antibiotic locks have resulted in significant improvement in catheter-related infections. However, widespread recognition of catheter-related complications like central vein stenosis, metastatic infections, and exhaustion of venous access sites preclude their being a viable alternative to AVF, furthering the need to explore AVG as a substitute. Placement of "early cannulation" AVG is a catheter sparing option in patients who are likely to have inadequate fistula maturation. Advances in biohybrid technology and tissue-engineered grafts are providing a robust opportunity to develop biocompatible graft materials with minimal tissue reactivity and thrombogenicity. Xenografts (bovine carotid artery grafts) are proving to be comparable and, in many cases, better than conventional polytetrafluoroethylene material. Older age, dialysis dependence, and smaller vein size are related to the appropriateness of AVG creation. An individualized approach in selecting optimal upper extremity vascular access option using patient-specific factors while incorporating the benefits of an AVG would greatly aid in achieving low catheter usage in the dialysis population.

Dialysis arteriovenous access monitoring and surveillance according to the 2017 Spanish Guidelines

The Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology (S.E.N.), vascular surgery (SEACV), interventional radiology (SERAM-SERVEI), infectious diseases (SEIMC), and nephrology nursing (SEDEN)), along with the methodological support of the Iberoamerican Cochrane Centre, has developed the Spanish Clinical Guidelines on Vascular Access for Hemodialysis. This article summarizes the main issues from the guideline's chapter entitled "Monitoring and surveillance of arteriovenous access." We will analyze the current evidence on conflicting topics such as the value of the flow-based screening methods for the arteriovenous access surveillance or the role of Doppler ultrasound as the imaging exploration to confirm suspected stenosis. In addition, the concept of significant stenosis and the criteria to perform the elective intervention for stenosis were reviewed. The adoption of these guidelines will hopefully translate into a reduced risk of thrombosis and increased patency rates for both arteriovenous fistulas and grafts.

Sex and gender disparities in the epidemiology and outcomes of chronic kidney disease

Improved understanding of sex and gender-specific differences in the aetiology, mechanisms and epidemiology of chronic kidney disease (CKD) could help nephrologists better address the needs of their patients. Population-based studies indicate that CKD epidemiology differs by sex, affecting more women than men, especially with regard to stage G3 CKD. The effects of longer life expectancy on the natural decline of glomerular filtration rate (GFR) with age, as well as potential overdiagnosis of CKD through the inappropriate use of GFR equations, might be in part responsible for the greater prevalence of CKD in women. Somewhat paradoxically, there seems to be a preponderance of men among patients starting renal replacement therapy (RRT); the protective effects of oestrogens in women and/or the damaging effects of testosterone, together with unhealthier lifestyles, might cause kidney function to decline faster in men than in women. Additionally, elderly women seem to be more inclined to choose conservative care instead of RRT. Dissimilarities between the sexes are also apparent in the outcomes of CKD. In patients with predialysis CKD, mortality is higher in men than women; however, this difference disappears for patients on RRT. Although access to living donor kidneys among men and women seems equal, women have reduced access to deceased donor transplantation. Lastly, health-related quality of life while on RRT is poorer in women than men, and women report a higher burden of symptoms. These findings provide insights into differences in the underlying pathophysiology of disease as well as societal factors that can be addressed to reduce disparities in access to care and outcomes for patients with CKD.

Sex and gender disparities in the epidemiology and outcomes of chronic kidney disease

Improved understanding of sex and gender-specific differences in the aetiology, mechanisms and epidemiology of chronic kidney disease (CKD) could help nephrologists better address the needs of their patients. Population-based studies indicate that CKD epidemiology differs by sex, affecting more women than men, especially with regard to stage G3 CKD. The effects of longer life expectancy on the natural decline of glomerular filtration rate (GFR) with age, as well as potential overdiagnosis of CKD through the inappropriate use of GFR equations, might be in part responsible for the greater prevalence of CKD in women. Somewhat paradoxically, there seems to be a preponderance of men among patients starting renal replacement therapy (RRT); the protective effects of oestrogens in women and/or the damaging effects of testosterone, together with unhealthier lifestyles, might cause kidney function to decline faster in men than in women. Additionally, elderly women seem to be more inclined to choose conservative care instead of RRT. Dissimilarities between the sexes are also apparent in the outcomes of CKD. In patients with predialysis CKD, mortality is higher in men than women; however, this difference disappears for patients on RRT. Although access to living donor kidneys among men and women seems equal, women have reduced access to deceased donor transplantation. Lastly, health-related quality of life while on RRT is poorer in women than men, and women report a higher burden of symptoms. These findings provide insights into differences in the underlying pathophysiology of disease as well as societal factors that can be addressed to reduce disparities in access to care and outcomes for patients with CKD.

Dialysis Access, Infections, and Hospitalisations in Unplanned Dialysis Start Patients: Results from the Options Study

Introduction

Unplanned dialysis start (UPS) associates with worse clinical outcomes, higher utilisation of healthcare resources, lower chances to select dialysis modality and UPS patients typically commenced in-centre haemodialysis (HD) with central venous catheter (CVC). We evaluated patient outcomes and healthcare utilisation depending on initial dialysis access (CVC or PD catheter) and subsequent pathway of UPS patients.

Methods

In this study patient demographics, access procedures, hospitalisations, and major infectious complications were analysed over 12 months in 270 UPS patients. PD technique survival and impact of switching from HD to PD was examined along with logistic regression to investigate factors predicting AV fistula formation.

Results

72 UPS patients started with PD catheter and 198 with CVC. PD patients were older and more comorbid but had a significantly lower number of access procedures while there was no difference in hospitalisation or major infections. 13/72 initial PD patients switched to HD and 1-year technique survival was 79%. 158/198 patients remained on HD and 73/158 reported permanent access formation. Older age, OR = 0.34 (CI, 0.17-0.68) and cardiac failure, OR = 0.31(CI, 0.13–0.78), were significant negative predictors of receiving fistula. Younger patients, OR = 0.29 (CI, 0.11–0.79) and those who received AVF, OR = 0.11 (CI, 0.03–0.38), had significantly lower odds of death.

Discussion

UPS with initial PD was possible in many patients and was associated with lower requirement for access procedures. AVF formation in UPS patients starting on HD was associated with better 1-year survival. Modality switching in UPS patients requires careful clinical management, including clinical practice patterns promoting permanent HD access formation.

Predictors of nonfunctional arteriovenous access at hemodialysis initiation and timing of access creation: A registry-based study

Determinants of nonfunctional arteriovenous (AV) access, including timing of AV access creation, have not been sufficiently described. We studied 29 945 patients who had predialysis AV access placement and were included in the French REIN registry from 2005 through 2013. AV access was considered nonfunctional when dialysis began with a catheter. We estimated crude and adjusted odds ratio (OR) with 95% confidence intervals (CI) of nonfunctional versus functional AV access associated with case-mix, facility characteristics, and timing of AV access creation. Analyses were stratified by dialysis start condition (planned or as an emergency) and comorbidity profile. Overall, 18% patients had nonfunctional AV access at hemodialysis initiation. In the group with planned dialysis start, female gender (OR 1.43, 95% CI 1.32–1.56), diabetes (OR 1.28, 95% CI 1.15–1.44), and a higher number of cardiovascular comorbidities (OR 1.27, 95% CI 1.09–1.49, and 1.31, 1.05–1.64, for 3 and >3 cardiovascular comorbidities versus none, respectively) were independent predictors of nonfunctional AV access. A higher percentage of AV access creation at the region level was associated with a lower rate of nonfunctional AV access (OR 0.98, 95% CI 0.98–0.99 per 1% increase). The odds of nonfunctional AV access decreased as time from creation to hemodialysis initiation increased up to 3 months in nondiabetic patients with fewer than 2 cardiovascular comorbidities and 6 months in patients with diabetes or 2 or more such comorbidities. In conclusion, both patient characteristics and clinical practices may play a role in successful AV access use at hemodialysis initiation. Adjusting the timing of AV access creation to patients’ comorbidity profiles may improve functional AV access rates.

Vascular access conversion and patient outcome after hemodialysis initiation with a nonfunctional arteriovenous access: a prospective registry-based study

BACKGROUND

Little is known about vascular access conversion and outcomes for patients starting hemodialysis with nonfunctional arteriovenous (AV) access. We assessed mortality risk associated with nonfunctional AV access at hemodialysis initiation, taking subsequent changes in vascular access into account.

METHODS

We studied the 53,092 incident adult hemodialysis patients included in the French REIN registry from 2005 through 2012. AV access placed predialysis was considered nonfunctional when dialysis began with a central venous catheter. Information about vascular access changes was obtained from treatment modality updates.

RESULTS

At hemodialysis initiation, AV access was functional for 47% of patients and nonfunctional for 9%; 44% had a catheter alone. After a 3-year follow-up, 63% of patients beginning hemodialysis with a nonfunctional AV access had changed to a functional one, 4% had had a transplant, 19% had died before any vascular access change, and 13% still used a catheter. Cox proportional hazard models with vascular access treated as a time-dependent variable showed an adjusted mortality hazard ratio (95% confidence interval) for patients with nonfunctional AV access who subsequently converted to functional access of 0.95 (95% CI 0.89-1.03) compared with the reference group with functional AV access since first hemodialysis, versus 1.43 (95% CI 1.31-1.55) for those who did not convert.

CONCLUSIONS

Among patients starting hemodialysis with a nonfunctional AV access, a substantial percentage may never experience successful vascular access conversion. Poor survival seems to be limited to these patients, while those who subsequently convert to functional AV access have similar mortality risk compared to patients with such access since hemodialysis initiation. Every effort should be made to obtain functional AV access in all suitable patients.

Offering Patients Therapy Options in Unplanned Start (OPTiONS): Implementation of an educational program is feasible and effective

Background

Patients with unplanned dialysis start (UPS) have worse clinical outcomes than non-UPS patients, and receive peritoneal dialysis (PD) less frequently. In the OPTiONS study of UPS patients, an educational programme (UPS-EP) aiming at improving care of UPS patients by facilitating care pathways and enabling informed choice of dialysis modality was implemented. We here report on impact of UPS-EP on modality choice and clinical outcomes in UPS patients.

Methods

This non-interventional, prospective, multi-center, observational study included 270 UPS patients from 26 centers in 6 European countries (Austria, Germany, Denmark, France, United Kingdom and Sweden) who prior to inclusion presented acutely, or were being followed by nephrologists but required urgent dialysis commencement by an acutely placed CVC or PD catheter. Effects of UPS-EP on choice and final decision of dialysis therapy and outcomes within 12 months of follow up were analysed.

Results

Among 270 UPS patients who had an unplanned start to dialysis, 214 were able to receive and 203 complete UPS-EP while 56 patients - who were older (p = 0.01) and had higher Charlson comorbidity index (CCI; p < 0.01) - did not receive UPS-EP. Among 177 patients who chose dialysis modality after UPS-EP, 103 (58%) chose PD (but only 86% of them received PD) and 74 (42%) chose HD (95% received HD). Logistic regression analysis showed that diabetes 1.88 (1.05 – 3.37) and receiving UPS-EP, OR = 4.74 (CI, 2.05 – 10.98) predicted receipt of PD. Patients choosing PD had higher CCI (p = 0.01), higher prevalence of congestive heart failure (p < 0.01) and myocardial infarction (p = 0.02), and were more likely in-patients (p = 0.02) or referred from primary care (p = 0.02). One year survival did not differ significantly between PD and HD patients. Peritonitis and bacteraemia rates were better than international guideline standards.

Conclusions

UPS-EP predicted patient use of PD but 14% of those choosing PD after UPS-EP still did not receive the modality they preferred. Patient survival in patients choosing and/or receiving PD was similar to HD despite age and comorbidity disadvantages of the PD groups.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0419-z) contains supplementary material, which is available to authorized users.

Vascular access should be tailored to the patient

A cornerstone of hemodialysis treatment is the creation of a functional and durable dialysis vascular access. Every patient with chronic kidney disease should have a plan of renal replacement therapy and access site protection. Factors having a crucial impact on vascular access selection include age, comorbidity, vessel quality, prognosis, dialysis urgency, and surgeon's preferences. Our medical group have reviewed these factors in our patients and, based on recently published data, developed a clinical decision tree for dialysis access in the chronic kidney disease patient. Vascular access care should be patient-centered with the aim to maximize patient survival without loss of vascular access options; and not focused only the primary patency rates of dialysis access procedures.

Vascular access scenario in Italy: evolution and comparison by two surveys (1998-2013)

PURPOSE

Dialysis settings have generally improved over the last decades, but the vascular access setting did not see significant advances and experienced a progressive worsening in epidemiology and clinical features. The aim of the study was to describe and compare evolution of vascular access in Italy over time.

METHODS

A national survey implemented in Italy last year is presented and compared to a previous survey performed in 1998. Present survey collected data from almost 50% of centers involved in vascular access.

RESULTS

The nephrologist participates in the management of vascular access in 97% of centers. Almost 40% of centers declare more than 40% of central venous catheters (CVCs) at first dialysis with maximum value being 60%. Prevalence of CVCs is greater than 20% in chronic prevalent patients in 38.8% of centers. According to the 2013 survey, CVCs account for 51.6% of procedures, while arteriovenous fistulae (AVF) and prostheses represent 42.4% and 6%, respectively. Nephrologists perform 73% of procedures on CVCs.From 1998 to 2013, a sharp increase in CVC prevalence was seen, in both incident and prevalent dialysis patients. This activity, mostly due to CVC management, is almost completely carried by nephrologists.

DISCUSSION

The variability in CVC utilization among centers suggests the lack of a shared policy in patients and access coupling. Quantitative criteria should be used to reduce inappropriate strategy in vascular access creation. Since this activity in Italy is organized at a local level without a shared organizational model, we should inquire whether a system managed so well in the past should now be rebuilt on the model of organ transplantation.