Abstract
Small branching veins that arise from the venous outflow of surgical arterial-venous fistulas (AVFs) are frequently seen during fistulograms performed to evaluate for poorly functioning AVFs. It is hypothesized that the presence of escape veins can decrease the performance of native AVFs during hemodialysis by diverting flow. Though interventional methods for exclusion of escape veins are effective, the mechanism of disruption these small branching vessels cause on flow through AVFs is unknown. Furthermore, an objective method for identifying escape veins that cause significantly diminished venous flow has not been defined. The following describes the detrimental nature of escape veins using tenants of physics and electrical circuitry. Subsequently, the proceeding study shows the identification of small branching escape veins in patients during fistulography. Intravascular pressure measurements were obtained proximal and distal to the ostium of the offending collaterals in these patients. Escape veins causing a pressure gradient of at least 5 mmHg were treated, and pressure measurements were repeated following intervention. The patients were entered into a database and hemodialysis blood flow rates were monitored to determine if escape vein intervention increased AVF performance.
Highlights
Escape vein collaterals are quite common after the creation of native arterial-venous fistulas (AVFs) and many times unavoidable, as the surgical exposure performed to create the arterialvenous (AV) anastomosis does not always allow the surgeon to identify these venous side branches [1]
The inclusion criteria for this study consisted of patients that had malfunctioning AVFs or complications of native AVF placement, and/or a venous pressure differential of at least 5 mmHg across any small branching escape vein
It has been shown with the results presented in this study that do escape vein cause impairment of native AVFs, but interventional methods for salvaging AVFs can be conducted
Summary
Escape vein collaterals are quite common after the creation of native arterial-venous fistulas (AVFs) and many times unavoidable, as the surgical exposure performed to create the arterialvenous (AV) anastomosis does not always allow the surgeon to identify these venous side branches [1]. The consequences of escape veins are thought to be the diversion of flow from the main channel of the fistula, as well as disruption of laminar flow, leading to decreased performance during hemodialysis (HD) [2]. In newly created native fistulas, escape veins can prevent equal pressurization across the anastomosis and venous outflow, leading to immature arterialization of the venous tract [3]. Escape veins are often inadvertently punctured during hemodialysis access, which can cause poor flow through the dialysis circuit, leading to prolonged or incomplete treatment times [4].
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
