Dahn M S, Ballerstadt R, Lange M P, Schultz J
Department of Surgery, Department of Veterans Affairs Medical Center, Detroit, MI, USA.
Crit Care Med. 1999 Aug;27(8):1598-602. doi: 10.1097/00003246-199908000-00036.
To develop a liver-specific biosensor system/catheter assembly that can be used to localize and cannulate the hepatic venous system without the need for fluoroscopic imaging. This would permit the bedside placement of a hepatic venous catheter for monitoring purposes without radiographic guidance.
Experimental, in vitro.
Experimental laboratory at a university center.
This was a simulation study to evaluate the ability of a cardiovascular monitoring catheter mounted with a liver-specific biosensor to anatomically identify a side arm tributary. The experimental system used for this study mimics the hepatic vein draining into the inferior vena cava and allows its localization without the need for assisted imaging. The biosensor design and catheter/sensor assembly function were studied in this in vitro model.
A liver-specific biosensor was developed by housing a homogeneous affinity fluorescence assay system sensitive to galactose in a microdialysis hollow fiber receptacle. A polyvinyl chloride tube containing a side arm was constructed to mimic the confluence of a venous tributary (i.e., the hepatic vein) with a major vascular channel (i.e., the vena cava). In this simulation, the side arm was continuously perfused with a liver-sensitive analyte (galactose) and the main channel was perfused with galactose-free buffer. A cardiovascular catheter containing a fiberoptic waveguide mounted with a galactose-sensitive fluorescent probe was advanced along the main conduit to assess its ability to identify the location of the galactose side arm infusion site.
The response of the fiberoptic sensor to different galactose concentrations was assessed and found to be almost linear over the concentration range of 0 to 2 mM, which encompasses the expected utilization range of this system. The variability in identifying the galactose infusion point (simulated hepatic vein) in a 15-cm conduit was 1.7 to 2.8 mm, or 1.1% to 1.9%.
The construction of a catheter/sensor system with the ability to provide accurate spatial/anatomical localization data for the hepatic venous system is feasible. This assembly will eliminate the need for ancillary imaging systems for catheter/sensor delivery to an individual organ system and potentially can be positioned at the bedside in a fashion similar to the pulmonary artery flotation catheter.
开发一种肝脏特异性生物传感器系统/导管组件，可用于在无需荧光透视成像的情况下定位和插入肝静脉系统。这将允许在无放射学引导的情况下在床边放置肝静脉导管以进行监测。
体外实验。
大学中心的实验实验室。
这是一项模拟研究，旨在评估安装有肝脏特异性生物传感器的心血管监测导管在解剖学上识别侧支支流的能力。本研究使用的实验系统模拟了流入下腔静脉的肝静脉，并允许在无需辅助成像的情况下对其进行定位。在这个体外模型中研究了生物传感器的设计和导管/传感器组件的功能。
通过将对半乳糖敏感的均相亲和荧光测定系统置于微透析中空纤维容器中，开发了一种肝脏特异性生物传感器。构建了一个带有侧臂的聚氯乙烯管，以模拟静脉支流（即肝静脉）与主要血管通道（即腔静脉）的汇合处。在这个模拟中，侧臂持续灌注对肝脏敏感的分析物（半乳糖），主通道灌注无半乳糖的缓冲液。将一根装有对半乳糖敏感的荧光探针的光纤波导的心血管导管沿着主管道推进，以评估其识别半乳糖侧臂注入部位位置的能力。
评估了光纤传感器对不同半乳糖浓度的响应，发现在0至2 mM的浓度范围内几乎呈线性，该浓度范围涵盖了该系统的预期使用范围。在15厘米长的管道中识别半乳糖注入点（模拟肝静脉）的变异性为1.7至2.8毫米，即1.1%至1.9%。
构建一种能够为肝静脉系统提供准确空间/解剖定位数据的导管/传感器系统是可行的。这种组件将消除将导管/传感器输送到单个器官系统时对辅助成像系统的需求，并且有可能以类似于肺动脉漂浮导管的方式放置在床边。
