Intra-access blood flow in patients with newly created upper-arm arteriovenous native fistulae for hemodialysis access

Hemodialysis Arteriovenous Fistulas: A Nineteenth Century View of a Twenty First Century Problem

This is a literature review which approaches the problem of successful use of arteriovenous fistulas for dialysis within the construct of Virchow's triad. By organizing the literature with regard to Virchow's concepts of blood flow, vascular injury, and thrombophilia an improved understanding arteriovenous fistula placement, maintenance and repair can be obtained. This process is designed to increase understanding and options for treatment by looking at this problem and using scientific knowledge gained in cardiology, oncology and vascular surgery medicine. Future approaches to fistulas will hopefully be a multifaceted and based in cellular pathophysiology as well as surgical and radiologic interventions and repairs.

Evolution of Hemodialysis Access Resistance: A Longitudinal 5-Year Model using Functional Principal Components Analysis

Purpose

Arteriovenous fistulae (AVF) and grafts (AVG) are the preferred accesses in hemodialysis (HD). By monitoring Access Resistance (AR) one can potentially identify problems with an established HD access, but little is known about how these changes in AR occur, or the variations between the two access types as they mature longitudinally. We postulated that AR evolves differentially between AVF and AVG, a critical aspect to further understanding of the natural history of HD accesses. To describe these changes, we applied a novel statistical methodology of Functional Principal Component (FPC) analysis.

Methods

Using ultrasound dilution flow studies, we retrospectively studied 479 functional HD accesses in which a total of 4573 assessments were made. Accounting for patient factors of age, race, gender and diabetes mellitus (DM) status, we employed a multivariate, mixed-effects model. Using the mean effects of those covariates, we then applied FPC analyses to assess the longitudinal, time-dependent changes between AVFs and AVGs over a 5-year period.

Results

Both types of upper-arm access were associated with a lower initial AR. Older age and DM were associated with a higher AR. Longitudinal AR varied significantly for both AVF and AVG, between the upper arm and lower arm. As a function of time, AVG was associated with an increasing AR. Conversely, AVF, especially upper-arm ones, demonstrated a longitudinal drop in AR.

Conclusions

Evolutionally AR can be predicted not only by the type of access, but also by the location along the arm of that access and by clinical patient factors. Longitudinal change in AR does differ between AVG and AVF. Our report provides the foundation of observed changes over time and provides insight as to how these variations are affected. We endorse ongoing surveillance to screen for clinical sequelae, even years from initial placement.

Arteriovenous Access: Infection, Neuropathy, and Other Complications

Complications of vascular access lead to morbidity and may reduce quality of life. In this module, we review both infectious and noninfectious arteriovenous access complications including neuropathy, aneurysm, and high-output access. For the challenging patients who have developed many complications and are now nearing their last vascular access, we highlight some potentially novel approaches.

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

BACKGROUND

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSION

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

Radial Artery–Perforating Vein Fistula for Hemodialysis

BACKGROUND

The proximal forearm antecubital fistula described by Gracz is a valuable option for autogenous vascular access for hemodialysis in patients with destroyed forearm veins or advanced arteriosclerotic and calcified radial arteries. Results obtained with a variant of the Gracz fistula are presented.

STUDY DESIGN

Patients with forearm vein destruction or failed distal radiocephalic fistulas were selected to have a variant of the Gracz fistula created and were followed up for 36 months. In each patient, the radial artery was anastomosed side to end or end to end to the perforating vein. Additionally, in some patients, the median cephalic or basilic vein was relocated subcutaneously to increase the accessibility of veins for puncture.

SETTING & PARTICIPANTS

Native arteriovenous fistulas (AVFs) in the cubital region using a perforating vein were created in 77 patients (34 women, 43 men) referred to the Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, Poland, from 1992 to 2006.

OUTCOMES & MEASUREMENTS

Percentages of successful fistula creation and primary patency rates, defined from fistula placement to any maintaining intervention, and cumulative patency, defined from placement to fistula abandonment, were assessed.

RESULTS

AVF creation was successful in 56 patients (73%). Primary patency rates during the follow-up period were 47% after 1 year, 43% after 2 years, and 39% after 3 years. Cumulative patency rates were 67% after 1 year, 56% after 2 years, and 53% after 3 years.

LIMITATIONS

These results reflect performance of a single center and thus may not be generalizable to surgeons less experienced in this technique.

CONCLUSIONS

Radial artery-perforating vein fistulas have an acceptable survival rate and do not produce circulatory complications. This method may be applicable for AVF creation in patients with forearm vein destruction/abnormalities and as a rescue procedure for an old clotted fistula after kidney transplant failure.