Preventing Vascular Access Dysfunction: Which Policy to Follow

Abstract

In the USA, three Clinical Performance Measures are currently in place: increasing the number of autologous arteriovenous fistulas (AVFs) among incident hemodialysis patients to 50% and to 40% in prevalent hemodialysis patients; to foster the surveillance of accesses with pre-emptive correction of problems before accesses thrombose or fail, and to reduce the use of catheters in prevalent patients to less than 10%. Reduction of catheters will automatically result from initiatives that increase the construction of AVFs and pre-emptive monitoring and surveillance of accesses for dysfunction. Therefore, policies that promote the latter two vascular access aspects are most important to develop and follow. Of these two, however, the most impact will be made by promoting a policy to increase AVF creation in the timeliest manner possible. Strategies and resources needed to achieve these policies are presented. The need for a team approach is emphasized.

Vascular Access Monitoring: Methods and Procedures – Something to Standardize?

“…Unfortunately, any pressure monitoring is far less reliable in native fi stulas (AVF) because of different pressure profi les from that of synthetic grafts (AVG) [11] and because of the frequent development of collateral vessels through which blood is drained without any signifi cant pressure increase in the access itself. This can be documented by our own data [12] ( table 1 ): PV and PIA values (calculated as (PA + PV)/2) were evaluated in 46 welldocumented accesses (30 forearm AVF, 5 upper arm AVF, and 11 AVG) in which balloon angioplasty (PTA) had eventually to be performed because of a stenosis.…”

Static intra-access pressure ratio does not correlate with access blood flow

“…The SIAPR method is based on the presumption that high SIAPR is an indirect indicator of low Qa associated with hemodynamically significant stenosis [2,3], and the value and utility of SIAPR for surveillance is therefore dependent on such a relationship existing between SIAPR and Qa. In fact, a number of studies have suggested that no correlation exists between SIAPR and Qa [5][6][7][8][9][10], while others suggest that this relationship does exist [2,3,11,12]. We could not find a published mathematical or theoretical basis for a correlation or surrogate relationship between SIAPR and Qa.…”

“…Therefore, without knowledge of the baseline Qa or the ability to quantify Qa at any given SIAPR, it is unlikely that trend analysis, using pressure (static or dynamic) alone, can be used to determine the appropriate timing for intervention, which is critical in order to avoid excessive unnecessary and costly interventions [2]. In an attempt to avoid excessive referrals using SIAPR surveillance, and to minimize costs and staff time, a hybrid model combining SIAPR and Qa surveillance protocols has been recommended [2,11]. However, if a Qa measurement tool is not available, another option would be to wait for an upward trend in SIAPR, and then attempt to confirm dysfunction by physical examination of the access or another noninvasive study-before referring the patient for invasive diagnostic evaluation and intervention.…”

Multislice Computed Tomographic Angiography in Evaluating Dysfunction of the Vascular Access in Hemodialysis Patients

“…Hemodialysis access failure is the most frequent cause of hospitalization of end-stage renal disease patients and also the main cause for the largest number of hospital days in some hemodialysis centers. The development of stenosis is the major cause of vascular access dysfunction, and, therefore, early diagnosis and treatment (including revising surgery and percutaneous intervention) of the stenosis is crucial to prolong the survival of dialysis shunts [1, 2]. …”