Two-Stage Offers No Advantages over Single-Stage Arteriovenous Creation: An Analysis of Multicenter National Data

Abstract

Traditionally, arteriovenous fistulas (AVF) involving the basilic vein (BV) have been created in 1 or 2 stages to allow time for the vein to enlarge before superficialization for potential better fistula maturation. Previous single institution studies and meta-analyses have found conflicting outcomes between single-stage and 2-stage procedures. Our study aims to use a large national database to assess the difference in outcomes between single-stage and 2-stage procedures for dialysis access. We studied all patients undergoing BV AVF creation in the Vascular Quality Initiative (VQI) from 2011 to 2021. Patients were split into single-stage or a planned 2-stage procedure for dialysis access. Primary outcomes included dialysis use with index fistula, maturity rate, and number of days from surgery to fistula use. Secondary outcomes included patency (defined by physical exam or imaging on follow-up), 30-day mortality, and postoperative complications (bleeding, steal syndrome, thrombosis, or neuropathy). Logistic regression models were used to assess the association between staged dialysis access procedures and primary outcomes of interest. The cohort consisted of 22,910 individuals of which 7,077 (30.9%) had a 2-staged dialysis access procedure and 15,833 (69.1%) had a single-staged procedure. Average follow-up was 345days in the single stage and 420days for 2-stage. Baseline characteristics were significantly different between the 2 groups in terms of medical comorbidities. Primary outcomes were significant for more patients in the 2-stage group undergoing dialysis with the index fistula compared to single stage (31.5% vs. 22.2%, P<0.0001), significant decrease in days to use in current dialysis patients (103.9days single stage versus 141.0days 2-stage, P<0.0001), and no difference in maturity at follow-up (19.3% single-stage and 17.4% 2-stage, P=0.354). Secondary outcomes revealed no difference in 30-day mortality or patency (89.8% single-stage and 89.1% 2-stage, P=0.383), but a significant difference in postoperative complications with a 2-stage procedure compared to 1-stage (1.6% vs. 1.1%, P=0.026). Finally, a spline model was used to determine that a preoperative vein of 3mm or less could be a cutoff in which a 2-stage procedure might be beneficial. This study demonstrates that when dialysis access fistulas are created using the BV, there is no difference in maturity rate or 1-year patency when assessing single-stage versus 2-stage procedures. However, 2-stage procedures significantly delay the time of first use of the fistula and increase postoperative complications. Therefore, we suggest performing single stage procedures when the vein is of appropriate diameter to minimize multiple procedures, complications and expedite time to maturity.