Abstract：
To maintain visualization and control temperature elevation during ureteroscopy, higher irrigation rates are necessary, but this can increase intrarenal pressure (IRP) and lead to adverse effects like sepsis. The IRP is also dependent on outflow resistance but this has not been quantitatively evaluated in a biological system. In this study, we sought to characterize the IRP as a function of irrigation rate in an in vivo porcine model at different outflow resistances. Ureteroscopy was performed in a porcine model with a 9.5 Fr prototype ureteroscope containing a pressure sensor. A modified ureteral access sheath (UAS) (11/13 Fr, 36 cm) was configured to adjust outflow resistance. IRP-irrigation rate curves were generated at four different outlet resistances representing different outflow scenarios. At lower irrigation rates, the pressure change in response to increased irrigation was gradual and non-linear, likely reflecting a \"compliant\" phase of the renal collecting system. Once IRP reached the range of 35-50 cm H2O, the pressure increased in a linear fashion with irrigation rate, suggesting that the distensibility of the collecting system had become saturated. The relationship between IRP and irrigation rate becomes linear during in vivo porcine studies once the initial compliance of the system is saturated. IRP is more sensitive to changes in irrigation rate in systems with higher outflow resistance. The modified UAS is a novel research tool which allows variance of outflow resistance to mimic different clinical scenarios. Knowledge of outflow resistance may simplify the decision to use an UAS.
摘要：
为了在输尿管镜检查期间保持可视化并控制温度升高，更高的灌溉率是必要的，但这会增加肾内压力（IRP）并导致败血症等不良反应。IRP也取决于流出阻力，但尚未在生物系统中进行定量评估。在这项研究中,我们试图将IRP表征为在不同流出阻力下的体内猪模型中灌溉速率的函数。在猪模型中使用9.5Fr原型输尿管镜（包含压力传感器）进行输尿管镜检查。改良输尿管入路鞘管(UAS)(11/13Fr,36cm）被配置为调节流出阻力。在代表不同流出情况的四个不同出口阻力下生成IRP-灌溉速率曲线。在较低的灌溉率下，响应于灌溉增加的压力变化是渐进的和非线性的，可能反映了肾脏收集系统的“顺从”阶段。一旦IRP达到35-50厘米H2O的范围，压力随灌溉速率呈线性增加，这表明收集系统的扩张性已经饱和。一旦系统的初始顺应性饱和,IRP和冲洗速率之间的关系在体内猪研究期间变为线性。在具有较高流出阻力的系统中，IRP对灌溉速率的变化更敏感。改良的UAS是一种新颖的研究工具，可以改变流出阻力以模拟不同的临床情况。了解流出阻力可以简化使用UAS的决定。
