An AVF is the result of a direct surgical anastomosis between an artery and a vein. This direct communication allows the vein to increase in size and \u201carterialize\u201d due to the increased pressure transmitted from the artery1<\/sup>. \u00a0Some authors refer to arterialization as venous remodeling because the entire vascular bed must undergo dramatic remodeling to accommodate blood-flow rates that have increased by a factor of 10-50 times over baseline values2<\/sup>.<\/p>\n Though several forms of AVF are possible, the classic AVF construction involves the radial artery and cephalic vein at the wrist (radiocephalic, wrist, or Cimino fistula), the brachial artery and cephalic vein in the anticubital fossa (brachiocephalic or upper arm fistula) or brachial artery and basilic vein (transposed brachiobasilic fistula) in the upper arm. Both American and Canadian guidelines recommend beginning with the most distal native vessel fistula possible (preferably the radiocephalic)3,4<\/sup>. The brachiocephalic and brachiobasilic fistulae are the second and third choices, respectively4<\/sup>. This order of AVF placement allows the later creation of a more proximal AVF if the distal AVF becomes unusable. Selection of the non-dominant arm is preferable in order to facilitate activities of daily living4<\/sup>.<\/p>\n When classic AVF construction is not possible, alternative upper extremity fistulae may be created through connection of the ulnar artery and basilic vein4<\/sup>. Fistula in the lower extremity, such as the superficial femoral-common femoral with thigh transpositions, are rare because of their inconvenient location and concerns about the possible development of distal ischemia. However, adequate outcomes (particularly decreased postoperative ischemia) have been reported with appropriate patient selection and selective intraoperative femoral vein tapering5<\/sup>.<\/p>\n Access decisions have a significant impact on patient outcome6<\/sup>. United States Renal Data System (<\/span>USRDS) data confirm that AVF have the lowest complication rates of any available vascular access (0.64 procedures per patient year versus 1.61 for arteriovenous grafts (AVG)6,7<\/sup>. Both diabetic and non-diabetic patients with AVF have a significantly lower relative risk of death than those with AVG and catheter8,9<\/sup>. For these reasons, the National Kidney Foundation-Dialysis Outcomes Quality Initiative (KDOQI) Clinical Practice Guidelines for Vascular Access recommend placement of an AVF access in preference to AVG or dialysis catheters. AVF placement is recommended at least 6 months prior to the initiation of chronic HD to allow sufficient time for AVF maturation and for possible revision4<\/sup>.<\/p>\n A functioning AVF may be difficult to achieve in some patient populations. Choosing a suitable \u201chealthy\u201d artery and vein, together with expert surgical technique is critical for adequate maturation and long term AVF success2<\/sup>.<\/p>\n Timely referral to a nephrologist and preoperative imaging to assess the presence of an adequate inflow artery and outflow vein is a prerequisite for appropriate AVF placement6<\/sup>. The Dialysis Outcomes and Practice Patterns (DOPPS) III reports that patients were less likely to use an AVF if they were female, of older age, had a greater body mass index or had diabetes, peripheral vascular disease or recurrent cellulitis\/gangrene10<\/sup>. These patient characteristics are associated with a high (approximately 40%) AVF primary failure rate11<\/sup>.<\/p>\n P\/N 101032-01\u00a0 Rev A 02\/2021<\/span><\/p>\nReferences:<\/h4>\n
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