Role of early postoperative ultrasonography in prediction of AV fistula failure in hemodialysis patients

Abstract

Background: Doppler ultrasonography (US) is the main imaging modality of hemodialysis AV fistula as it is safe non-invasive accurate modality. This study is to measure the arteriovenous (AV) fistula blood flow during early postoperative period (7–14 days) and assess its predictive role in AV fistula failure in hemodialysis patients. Color Doppler ultrasonography (CDU) was used to estimate the blood flow in the AV fistula of 100 patients at (7–14 days) after the fistula creation. The performance of fistula blood flow during early postoperative periods for predicting fistula failure was evaluated, and optimal cutoff value was determined. Results: During the follow-up period (6 months), we classified the fistulas as 82 mature, and 18 failed. The blood flow was considerably lower in the failure group than that in the mature group at the early postoperative period (P value = 0.001). The areas under the curves (AUC) were 0.952, and the cutoff value was 200.5 ml/min. The sensitivity of CDU in prediction of fistula failure is 99% with negative predictive value 94% and accuracy 97%, and with specificity 89% and positive predictive value 98%. Conclusion: Measuring blood flow of the AV fistula at the early postoperative period probably has a predictive role in the AV fistula failure. There is risk of failure if the blood flow less than 200 ml/min at (day 7–14).