Comparison of radiocephalic fistulas placed in the proximal forearm and in the wrist

The Alpha to Omega of Dialysis Access: Arteriovenous Fistula and Graft (Part 1)

Background: Vascular access is a critical determinant of hemodialysis efficacy in patients with end-stage kidney disease (ESKD). The choice between arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs) influences long-term dialysis outcomes, with AVFs offering superior patency but higher maturation failure rates and AVGs providing immediate usability at the expense of increased complications. Recent advancements in endovascular techniques and biomaterials have introduced novel approaches to optimizing vascular access. Purpose: This review examines the latest evidence on AVF and AVG creation, focusing on factors affecting maturation, long-term patency, and emerging minimally invasive techniques, such as percutaneous AVF creation, to enhance hemodialysis access outcomes. Research Design: A systematic review of current literature, clinical guidelines, and innovations in vascular access for dialysis patients was conducted. Emphasis was placed on comparative effectiveness studies, patency and complication rates, and new endovascular approaches. Study Sample: Data were sourced from clinical trials, registry reports, and systematic reviews evaluating AVF and AVG outcomes, as well as emerging endovascular fistula technologies. Data Collection and/or Analysis: Key parameters such as patency rates, infection rates, thrombosis incidence, and maturation success were analyzed. Particular attention was given to procedural innovations, including bioengineered grafts and percutaneous fistula creation, assessing their impact on long-term dialysis access viability. Results: AVFs maintain superior long-term patency but are hindered by primary failure rates, necessitating interventions for maturation. AVGs, while more prone to infection and thrombosis, offer a viable alternative when native vessels are unsuitable. Endovascular AVF creation has demonstrated high technical success and promising long-term outcomes, reducing the need for traditional surgical approaches. Advances in biomaterials and adjunctive pharmacologic therapies may further improve vascular access durability. Conclusions: Individualized vascular access planning remains essential to optimizing hemodialysis outcomes. The evolution of minimally invasive techniques, coupled with improved patient selection criteria and emerging biomaterials, offers new opportunities for enhancing dialysis access longevity. Future research should focus on refining endovascular approaches and integrating novel technologies to minimize complications and improve access patency.

Comparison of distal radiocephalic fistula vs proximal radiocephalic fistula

Background:

Distal radiocephalic fistula (DRCF) at wrist is the first option of vascular access in patients undergoing hemodialysis. In patients with a failed DRCF or unsuitable for DRCF the current recommendation is to perform a brachiocephalic fistula. Proximal forearm radiocephalic fistulas (PRCF) are created less frequently. The aim of the present study was to evaluate the outcomes of PRCF and DRCF.

Material and Methods:

A longitudinal study was conducted in the department of MKCG Medical College from January 2018 to July 2019. Data was collected and entered in Microsoft excel. The analysis was done by R version 3.6.1. Quantitative data were presented in the form of Mean and SD and were tested by unpaired t-test. Categorical data were presented as count and proportion and was tested by Chi-square test or if applicable Fischer's exact test. Comparison between two procedures was done by Kaplan-Meier method and evaluated by the log-rank test. With the 95% of Level of significance, P value <0.05 was consider statistically significant during analysis.

Results:

The demographic data of the two patient groups were similar except that those with PRCF were more likely to have had a previous access and caliber of distal vessel was less. Early failure was lower for PRCF than DRCF (6.06% vs 15%). Primary patency rate at one year was 87.87% in PRCF vs 70% in DRCF.

Conclusion:

A PRCF can be a suitable alternative to a brachiocephalic fistula in patients who cannot receive a DRCF.

Two-year cumulative patency of endovascular arteriovenous fistula

BACKGROUND AND OBJECTIVES

The recent advent of a device to create a proximal radial artery arteriovenous fistula using an endovascular approach to create the anastomosis represents a significant advance in dialysis access creation. This endovascular arteriovenous fistula offers the beneficial attributes of the proximal radial artery arteriovenous fistula while adding the advantages of avoiding a surgical procedure. The endovascular arteriovenous fistula can be created safely, functions well, has excellent patency, and has a high degree of patient satisfaction. The purpose of this study is to report the 2-year cumulative patency rate for a large multicenter cohort of endovascular arteriovenous fistula cases.

DESIGN

An endovascular arteriovenous fistula was created in 105 patients using either local or regional anesthesia and conscious sedation. Patient data were obtained from each program's electronic health record system. Data collection was truncated at 2 years postprocedure and used to calculate cumulative patency. Post-access creation patient satisfaction was assessed.

RESULTS

A physiologically mature arteriovenous fistula (blood flow ⩾500 mL/min and a target vein internal diameter ⩾4 mm) was obtained in 98%. A clinically functional arteriovenous fistula (supporting two-needle dialysis according to the patient's dialysis prescription) was demonstrated in 95%. Access failure resulting in the loss of access occurred in eight cases during the study period. The cumulative patency rate at 6, 12, 18, and 24 months was 97.1%, 93.9%, 93.9%, and 92.7%, respectively. The post-procedure patient evaluation emphasized a high level of patient satisfaction.

CONCLUSION

The proximal radial artery arteriovenous fistula created using an endovascular approach for the anastomosis is associated with excellent 2-year cumulative patency and is associated with a high level of patient satisfaction.

Factors Associated with Secondary Functional Patency After Percutaneous Transluminal Angioplasty of the Early Failing or Immature Hemodialysis Arteriovenous Fistula

PURPOSE

To evaluate the efficacy of percutaneous transluminal angioplasty for early failing hemodialysis arteriovenous fistulas (AVFs) and predictors of secondary functional patency (FP).

METHODS

A review of our endovascular registry database showed that 61 patients with early failure after a surgically created AVF underwent endovascular intervention between 2011 and 2016. Median time from AVF creation to first intervention was 5.6 weeks. Median duration of follow-up was 14 months. Items related to the technical success rate and primary and secondary FP, and factors associated with secondary FP were analyzed.

RESULTS

Technical success was achieved in 55 (90%) of 61 patients. The primary and secondary FP rates were 42% and 65% at 12 months, respectively. Multivariate analysis showed that lesion length (HR; 1.15, P = 0.001) and lesions including juxta-AVF (the portion of fistula vein within 2 cm of the arteriovenous anastomosis, HR; 6.23, P = 0.008) were factors associated with reduced secondary FP. ROC curve analysis indicated lesion length with cutoff value ≥ 9 cm as a risk factor for reduced secondary FP. Secondary FP at 12 months for patients with no risk factors, with 1, and with 2 was 86%, 65%, and 0%, respectively. There was a significant difference in secondary FP rates among these groups (P = 0.001).

CONCLUSIONS

A lesion length and juxta-AVF lesion are the risk factors for reduced secondary FP. The secondary FP rate at 12 months is acceptable in patients without risk factors.

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.

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.

The snuffbox fistula should be preferred over the wrist arteriovenous fistula

OBJECTIVE

The snuffbox arteriovenous fistula (SBAVF) is the most distal native vascular access. Although published data show a favorable outcome, the SBAVF is not strongly recommended by the guidelines. The present study compared the patency of SBAVFs and wrist AVFs (WAVFs).

METHODS

All 416 AVFs created by the same nephrologist from March 2006 to October 2014 were reviewed. From 416 procedures, 47 SBAVFs and 77 WAVFs with vessels suitable for a SBAVF were selected.

RESULTS

Although vessel diameters used for construction of the SBAVFs were smaller than those used for WAVFs, the outcome of vascular access was similar. At 18 months, primary patency was 72% for SBAVF and 65% for WAVF (P = .48), and secondary patency was 93% for SBAVF and 94% for WAVF (P = .89).

CONCLUSIONS

In our experience, a SBAVF performs as well as a WAVF up to 18 months after creation. We suggest favoring SBAVF, especially in young patients without comorbidities, as the primary vascular access.

Effect of a Rapid Clinical Protocol to the Conversion from Central Venous Hemodialysis Catheter to Arteriovenous Access

Purpose

Evaluation of the rapid conversion protocol that includes an ambulatory dialysis access center (DAC), and a three-step clinical pathway, to the conversion rate from central venous hemodialysis (HD) catheter to functioning arteriovenous (AV) access.

Methods

Prospective data were collected on 97 consecutive catheter-dependent HD patients. DAC is defined as an ambulatory unit, able to accommodate clinic visits, ultrasound examinations, surgical, interventional and hybrid procedures. Step I: initial evaluation, vein mapping and creation of AV access. Step II: clinical evaluation in two weeks and if failure identified, secondary procedure to restore function. Step III: evaluation in four weeks after creation, and additional procedure to promote maturation if indicated. The success rate, time to conversion and time to catheter removal were recorded.

Results

From the 97 consecutive referred patients, eight patients were excluded. From the remaining 89 patients, 99% were successfully converted to AV access. Seventy-three percent of the patients were converted to native arteriovenous fistulae and 27% of the patients to prosthetic arteriovenous shunts. The median time from creation to HD catheter removal was 63 (SD 41) days. Fifty-two percent of the patients required at least one additional secondary procedure to accomplish successful conversion

Conclusions

High rates of timely conversion from catheter to AV access, primarily AV fistulae, can be accomplished within the context of the rapid conversion protocol.

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.

Primary patency rate of native AV fistula: long term follow up

The number of end stage of renal disease patients that need dialysis or renal transplantation increased in the world. Insertion and maintenance functional vascular access remain the challenging problem. Arteriovenous fistula is the common access for dialysis but complication and its failure is the main problem. The aim of this study is to evaluate patients with arteriovenous fistula during 4 years and describe the probable influenced factors on fistula patency. In this analytical descriptive study, we fallowed 245 patients during 4 years and evaluated them for primary failures and effective factors on vascular patency. The patients were asked about demographic data, how to caring condition arteriovenous fistula, dialysis and complications. The mean age of the patients was 47.77 years. The underline diseases were hypertension (43.3%), hypertension and diabetes mellitus (21.2%) and diabetes mellitus (4.5%). According Log rank test there were meaningful results between arteriovenous patency with sex and dialysis (P < 0.05). Our result of primary patency at 6 months, 1, 2, 3 and 4 years for all patients were 79.5%, 70%, 65%, 60.5% and 48%. Our study showed dialysis could increase the fistula patency rate. Other factors were not associated with primary patency. It seems ESRD patients undergoing dialysis have better fistula patency, may be due to homeostasis abnormalities induced by their particular conditions.