Heerwagen Søren T, Lönn Lars, Schroeder Torben V, Ladefoged Søren D, Hansen Marc A
Department of Interventional Radiology, Rigshospitalet, Copenhagen, Denmark.
J Vasc Access. 2012 Jan-Mar;13(1):45-50. doi: 10.5301/JVA.2011.8443.
The purpose of this study was to perform bench and clinical testing of a catheter-based intravascular system capable of measuring blood flow in hemodialysis vascular accesses during endovascular procedures.
We tested the Transonic ReoCath Flow Catheter System which uses the thermodilution method. A simulated vascular access model was constructed for the bench test. In total, 1960 measurements were conducted and the results were used to determine the accuracy and precision of the catheters, the effects of external factors (e.g., catheter placement, injection duration), and to test for systematic bias. In the clinical study, two interventional radiologists conducted a total of 250 measurements in 14 patients with arteriovenous fistulas to determine clinical precision and enable testing for bias between measurers.
Accuracy was excellent for both catheters with a high level of agreement between results from the ReoCath Flow Catheter System and the reference flowmeter. Clinical precision, expressed as the mean coefficient of variation, was 5.9% and 4.7% for the antegrade and retrograde catheters, respectively. Flow measurements were significantly affected by the distance between a stenosis and the tip of a retrograde catheter with the effect being proportional to the degree of stenosis. There was no systematic bias between measurers.
The Reocath Flow Catheter System was found to be accurate and precise. Reliable results require careful attention to catheter placement. Blood flow measurements provide unique information on the hemodynamic status of a vascular access and have the potential to optimize results of interventions.
本研究旨在对一种基于导管的血管内系统进行实验台测试和临床测试，该系统能够在血管内手术过程中测量血液透析血管通路中的血流量。
我们测试了采用热稀释法的Transonic ReoCath血流导管系统。构建了一个模拟血管通路模型用于实验台测试。总共进行了1960次测量，结果用于确定导管的准确性和精密度、外部因素（如导管放置、注射持续时间）的影响，并检测系统偏差。在临床研究中，两名介入放射科医生对14例动静脉内瘘患者共进行了250次测量，以确定临床精密度并检测测量者之间的偏差。
两种导管的准确性都非常好，ReoCath血流导管系统的结果与参考流量计的结果高度一致。以平均变异系数表示的临床精密度，顺行导管和逆行导管分别为5.9%和4.7%。血流测量受狭窄部位与逆行导管尖端之间距离的显著影响，其影响程度与狭窄程度成正比。测量者之间没有系统偏差。
发现Reocath血流导管系统准确且精密。要获得可靠结果需要仔细注意导管放置。血流量测量提供了关于血管通路血流动力学状态的独特信息，并且有可能优化干预结果。
