Ultrasound-Guided Reverse Needle Cannulation of a Thrombosed Arteriovenous Fistula to Improve Dialysis Adequacy: A Case Report

Background: Dialysis adequacy is commonly assessed using Kt, a measure of urea clearance. Vascular access dysfunction, particularly thrombosis and access recirculation, may compromise dialysis efficiency despite apparently adequate treatment parameters. Ultrasound assessment of vascular anatomy can help identify individualized cannulation strategies to optimize dialysis delivery. Case Presentation: We report the case of a 78-year-old man undergoing maintenance hemodialysis who exhibited persistently low Kt values despite adequate dialysis time and blood flow. Doppler ultrasound revealed complete occlusive thrombosis involving the cephalic vein, resulting in altered venous drainage. Based on these findings, the conventional cannulation configuration was reversed by exchanging the arterial and venous needle positions. Dialysis adequacy during 11 consecutive sessions using reverse cannulation was compared with that of the previous 12 conventional sessions matched for treatment duration and dialysis volume. Results: Reverse needle cannulation was associated with improved dialysis adequacy. Mean Kt increased from 46.9 ± 6.7 L with conventional cannulation to 57.3 ± 5.8 L after reverse cannulation (p = 0.002), while dialysis duration and processed blood volume remained comparable between both periods. Conclusions: In selected patients with complex vascular anatomy secondary to arteriovenous fistula thrombosis, ultrasound-guided reverse needle cannulation may improve dialysis adequacy without changing treatment duration or the prescribed extracorporeal blood flow rate. This case highlights the value of individualized vascular access assessment and tailored cannulation strategies in patients with vascular access dysfunction.