Clinical Value of Intraoperative Transit-Time Flow Measurement for Autogenous Radiocephalic Arteriovenous Fistula in Patients with Chronic Kidney Disease

Abstract

Background: The intraoperative assessment of autogenous arteriovenous fistulas (AVF) is crucial for achieving an optimal surgical outcome; however, it is not easy to predict the adequacy of surgically created AVF. We used the transit-time flow measurement (TTFM) method to assess the anastomotic quality of AVF and to identify the cutoff value for predicting prognosis of established AVF. Methods: Retrospective study, a total of 187 patients were included in this study. History of diabetes mellitus, hypertension, preoperative vein size, blood pressure, and other demographic data were collected. Surgery for creating radiocephalic AVF was performed by one surgeon, and intraoperative TTFM was performed. Flow parameters were recorded, including the maximal, mean, and minimal flow, and the pulsatility index (PI). Only mean flow <= 70 mL/min regarded as failure. We reviewed patients' follow-up, and we defined "successful AVF" when the patients who managed hemodialysis using established AVF without clinical problems during follow-up. Results: All patients had a successful operation with adequate mean flow. The established mean flow from the radial artery to the cephalic vein was 199.8 +/- 92.7 mL/min, and the PI was 0.57 +/- 0.16. None of the patients had any complication during the immediate postoperative period, including infection. Mean follow-up period were 72.4 +/- 42.7 weeks. Hemodialysis was maintained in 77.5% of the patients by using the established AVF, and the time to first hemodialysis with the established AVF after surgery was 61.0 +/- 22.7 days. Correlation analysis revealed that the time to first hemodialysis was related with mean flow (P = 0.049) and PI (P = 0.009) and successful AVF was related only with PI (P = 0.028). According to curve fit and regression analysis, PI for 95% limit of successful AVF was from 0.43 to 0.77. Conclusions: Intraoperative TTFM is valuable for the assessment of the quality of established AVFs. Especially PI was correlated successful hemodialysis management for over 12 months, the recommended acceptable range was 0.43-0.77.