RESUMO
Vascular access is a critical issue in the management of patients with end-stage renal failure and is the leading cause of hospitalization in this group of patients. The object of this study was to find out whether it would be possible to predict vascular access patency rates based on preoperative Doppler assessment of vessel size. Furthermore, this study sought to define the relationship between access flow rate and access patency. This was a prospective cohort conducted at St. Mary Hospital, London, between 2002 and 2005, where a group of 83 patients who underwent venous and arterial Doppler prior to creation of arteriovenous access underwent regular postoperative assessment at 3-month intervals of their access using flow rate and usability of the access as outcome measures. The collected data showed a positive correlation between vein size and access patency rate. Preoperative vein diameters of 1.5-3.9 mm showed a patency rate of 71.08% at follow-up at 13.8 months (range, 12-42 months). Although large-sized vessels are correlated with long-term patency, smaller vein diameters (1.5-2 mm) were found to have an acceptable patency rate at 20% over 12 months. Furthermore, data indicated a positive correlation between access flow rate and access patency, with flow rates of above 700 ml/min being associated with a patency rate of 70% at 12-month follow-up.