バスキュラーアクセス機能評価における狭窄径・血流量・RIの有用性

抄録

[Background] Ultrasound examination of vascular access (VA) is non-invasive method and can evaluate the morphology and blood flow in the vessel. Therefore, it has become to be performed in a number of dialysis facilities. But at present, there has not been established its way, parameters and those normal values to be recommended.
[Patients and Methods] In our study, we chose three parameters, blood flow volume, resistance index, and stenosis diameter as predictive values for VA failure. We measured those parameters to 137 chronic hemodialysis patients and evaluated the usefulness and cut-off value.
[Results] Of 137 cases, mean blood flow volume of the brachial artery was 1344±791 mL/min, and resistance index was 0.51±0.11, respectively. Among them, stenosis was detected 52 cases (38%), and mean stenosis diameter was 2.14±0.41 mm, respectively. After the measurement, we followed them for six months, and detected 12cases (8.8%) as VA failure, who underwent reconstructive surgery or surgical closure.
In a detailed study, the risk factors of VA failure were blood flow volume below 300 mL/min and/or resistance Index above 0.7 and/or stenosis diameter below1.5 mm. With 1 or more parameters matched, we can identify the VA failure with an accuracy of 93.4%, sensitivity of 75.0% and specificity of 95.2%.
[Conclusion] These results suggest that those parameters, blood flow volume, resistance index , and stenosis diameter in ultrasound examination are clinically useful for predicting VA failure