PROGNOSTIC VALUE OF INTRAOPERATIVE BLOOD-FLOW MEASUREMENTS IN VASCULAR ACCESS SURGERY

Background. The purpose of this study was to correlate intraoperative blood flow measurements with outcome in vascular access surgery. Metho ds. In 303 patients, 389 vascular access operations were performed. In traoperative blood flow measurements were made immediately following c onstruction of 227 autogenous and 162 prosthetic arteriovenous fistula s (AVFs) using a handheld flowprobe. Blood flow measurements were stra tified by demographic variables such as age, race, sex, and presence o f diabetes and were correlated with primary and secondary (assisted) p atency. Statistical methods included life-table analysis and Cox propo rtional hazards model. Results. Blood flow increased progressively fro m distal to proximal access sites and was not significantly affected b y age, race, sex, or presence of diabetes. Autogenous AVFs with flow r ates at or below 320 mL/min and polytetrafluoroethylene (PTFE) grafts with flow rates at or below 400 ml/min had significantly worse primary and secondary patency rates compared to their higher flow counterpart s at all sites. Using hazard analysis flow rate was the single most im portant determinant of primary and secondary patency. PTFE grafts with flow rates at or below 400 mL/min also required more interventions (1 .58 per patient-year) and failed sooner (median time, 0.5 +/- 4.7 mont hs) than grafts with flow rates above 400 mL/min (1.08 interventions p er patient-year; P = .03; median time, 1.6 +/- 5.0 months; P = . 003). Conclusions. Intraoperative measurements of access blood flow provide objective, reliable data that correlate with outcome. Routine use of this technology might lead to more efficient management of patients un dergoing hemodialysis access surgery.