Doppler ultrasound assessment of well-functioning native hemodialysis access: comparison with sufficient dialysis

ABSTRACT

Malfunction of vascular accesses is a common cause of morbidity in hemodialysis patients. The purpose of the present study was to evaluate the flow volume and the diameter of the feeding artery in asymptomatic, well-functioning hemodialysis access with Doppler ultrasound. From March 2006 to February 2007, we examined the functioning mature arteriovenous fistula [AVF] of 69 hemodialysis patients by Doppler ultrasound in Imam Reza hospital, Mashhad. The measured flow volume, primary renal disease, AVF type and location, and the demographic data were recorded. All statistical analyses were performed with the Chi square test, the Student's t test and one-way ANOVA. Pearson correlation coefficient was also calculated. Of the 69 patients, 30 [43%] had an antecubital AVF. Overall, the mean +/- SD flow volume was 1665 +/- 554 mL/min. The majority of accesses [n = 52] had normal flow volume [500-1200 mL/min], 15 patients had high-flow fistulas [>1200 mL/min] and 4 had critical flow rates of < 500 mL/min. The flow volume was significantly higher in the antecubital AVF than that placed in more distal positions. The mean diameter of the feeding artery at the measurement site was 6.0 mm. There is a linear correlation between the diameter of the feeding artery and the mean flow rate [r = 0.76, p < 0.001]. No significant difference was observed between the type of anastomosis and the flow rate [p = 0.14]. There is a high level of abnormalities, especially high flow volume, in well-functioning mature AVFs. Color Doppler ultrasonography makes early detection of the patients with a higher risk possible and it can also guide the surgeon to select the surgical procedure