Abstract:

Objective Autogenous arterio-venous fistulas(AVF) are regarded as the optimal vascular access for chronic hemodialysis(CHD) patients. This study was conducted to investigate the association of clinical indexes and vascular access thrombosis in chronic hemodialysis patients. Methods Fifty-six CHD patients with AVF were followed up for over 6 months. Vascular access blood flow was measured by the ultrasound dilution technique. Their clinical indexes were collected. Thrombotic events were recorded during follow-up. Results A total of 11 thrombotic events in 56 accesses were documented throughout this study duration. Patients were divided into two groups: thrombotic group and non-thrombotic group. They were comparable in age, gender, and weight index. It was found that the access blood flow was much more decreased in the thrombotic group than in nonthrombotic patients at the beginning of this study〔(337.3±236.9)mL/min vs (748.5±386.7)mL/min; P=0.001〕. However, there was no statistically significant difference in the blood pressure, hemoglobin concentration, blood plaque, clotting time and blood lipids. The dialysis adequacy(KT/v) was reduced in the thrombotic group compared to the other group(1.3±0.3 vs 1.5±0.3, P=0.038). The AVF cumulative survival rate was about 65.2%, when their access flow was less than 500 mL/min. There was a 4.5 fold increase in the relative risk of thrombosis for patients with an access blood flow less than 500 mL/min compared to those with more than 500 ml/min. Conclusion In CHD patients with AVF, the less access blood flow was, the more possible the vascular access thrombosis. When vascular access blood flow was blow 500 mL/min, it was a strong predictive factor for thrombosis. It was necessary to correct the reduced flow to improve the dialysis adequacy.

Key words: hemodialysis, autogenous arterio-venous fistulas, thrombosis