Characterizing flow distributions in AV fistulae for haemodialysis access

Background. The arteriovenous fistula is the most widely used means of enab ling vascular access for chronic haemodialysis. When interest in vascular a ccess was at its height, in the 1970s, a substantial amount of work was car ried out on the physiology of arteriovenous fistulae and on the relationshi p between fistula flow and patency. One omission in the catalogue of studie s was research into the distribution of flow in the fistula and the effects on surgical outcome. Method. To address this issue, 30 patients with end-to-side radiocephalic f istulae were studied. Flow measurements were made intraoperatively, and at various intervals postoperatively using colour-how ultrasonography. Results. In 22 cases, the development of the fistula was monitored at regul ar intervals for periods of up to 27 months. In seven of the 30 fistulae, f low in the distal artery was antegrade, while in the remaining 23, distal a rtery flow was retrograde. The proportion of fistula flow supplied by the p roximal and distal arteries varied considerably. Conclusion. Despite the wide range of flow distributions in the fistulae st udied, flow distribution did not appear to affect fistula maturation or lon g-term function.