Peri-Operative Surgical and Anaesthetic Predictors of Autogenous Arteriovenous Fistula (AVF) Maturation: A Retrospective Cohort Analysis.

Abstract

Objective: The maturation of autogenous arteriovenous fistulas (AVFs) remains unpredictable despite being the preferred vascular access for haemodialysis. Early identification of at-risk AVFs could improve outcomes and reduce unnecessary interventions. The 2019 Kidney Disease Outcomes Quality Initiative (KDOQI) recommends a volume flow (Qa) threshold of >500 mL/min, replacing the 2006 >600 mL/min benchmark, as a marker of fistula health. This study evaluates whether perioperative and follow-up Qa measurements are associated with AVF maturation, with particular focus on pre-operative and immediate post-operative Qa, which remain underexplored. The influence of anaesthetic and demographic factors was also assessed.

Methods: This single-centre retrospective cohort study included 31 patients undergoing AVF creation. Inflow artery Qa was measured pre-operatively, immediately post-operatively, and at follow-up. Demographics, comorbidities, anaesthetic parameters, and AVF characteristics were obtained from clinical records. Successful maturation was defined as Qa ≥500 mL/min on duplex ultrasound at six weeks and the ability to sustain dialysis (two-needle access for ≥ two-thirds of sessions in the first month without functional concerns).

Results: Of 31 AVFs created, 22 (71%) matured by follow-up, either directly (n = 15, median Qa 1050 mL/min) or after fistuloplasty (n = 7, median Qa 800 mL/min). Nine (29%) failed to mature of which six did not undergo fistuloplasty (median Qa 270 mL/min), and three failed despite fistuloplasty (median Qa 332 mL/min). Successful AVFs demonstrated higher median Qa pre-operatively (91 vs 70 mL/min, p = 0.08), post-operatively (495 vs 234 mL/min, p = 0.02), and at follow-up (925 vs 280 mL/min, p < 0.001). The majority of AVF with Qa >700 mL/min at follow-up matured (OR 22.17, 95% CI 3.25-151.3, p = 0.002). No significant associations were found with age, smoking, diabetes, or anaesthetic factors.

Conclusion: Perioperative Qa measurement is a practical, low-cost predictor of AVF maturation. The >500 mL/min Qa threshold supports current KDOQI guidance. Pre-operative Qa differences represent a promising area for future research, while demographic and anaesthetic factors showed limited predictive value.