Department of Urology, Ninewells Hospital, Dundee, Scotland.
J Endourol. 2010 Dec;24(12):1915-20. doi: 10.1089/end.2010.0188. Epub 2010 Nov 10.
Our aim was to determine the optimal size of access sheath for ureteroscopy and stone lasertripsy to achieve good irrigant flow while maintaining the lowest possible intrarenal pressure.
We used an in vitro anatomic model into which a pressure transducer was incorporated. Cook Peel-Away 10F, Flexor 12F, 14F, 16F single lumen, and a new 14F Flexor dual-lumen sheath were tested. Irrigant flow and intrarenal pressure were measured with an empty ureteroscope working channel and with a 1.4F or 2.4F basket within the working channel with a hydrostatic pressure of 1 m and 2 m, respectively. For the dual-lumen sheath, the irrigation was either connected to the scope or the second channel of the access sheath. Two other configurations were tested: 4F ureteral catheter placed alongside a 10F sheath (configuration 1) or a 5F ureteral catheter within a 16F access sheath (configuration 2).
With an empty working channel, irrigant flow increased with sheath diameter. The presence of a 1.4F or 2.4F basket, however, reduced flow up to 65% and 90%, respectively. Increasing the hydrostatic column to 2 m height improved the irrigant flow but with a predisposition to a higher intrarenal pressure. Using configurations 1 and 2, the flow rates improved by 250% and 700%, respectively, with a 2.4F basket in the working channel, and could also be used with a 2 m hydrostatic column without raising the intrarenal pressure.
Increased access sheath diameter does not improve flow when the working channel of a flexible ureteroscope is occupied. Our proposed configuration of a ureteral access catheter placed inside or alongside the access sheath provides by far the highest flow rates without a rise in the intrarenal pressure.
本研究旨在确定输尿管镜和激光碎石术中最佳的输尿管鞘管大小，在保持最低肾内压的同时实现最佳的冲洗液流量。
我们使用了一种内置压力传感器的体外解剖模型。分别对 Cook Peel-Away 10F、Flexor 12F、14F、16F 单腔管和新的 14F Flexor 双腔管鞘进行了测试。在输尿管镜工作通道内插入空镜和 1.4F 或 2.4F 篮筐，分别施加 1m 和 2m 静水压力，测量冲洗液流量和肾内压。对于双腔管鞘，冲洗可以连接到镜体或鞘管的第二通道。还测试了另外两种配置：4F 输尿管导管置于 10F 鞘管旁（配置 1）或 5F 输尿管导管置于 16F 鞘管内（配置 2）。
在空工作通道中，随着鞘管直径的增加，冲洗液流量增加。然而，当工作通道内存在 1.4F 或 2.4F 篮筐时，流量分别减少了 65%和 90%。将静水柱升高到 2m 高度可以提高冲洗液流量，但肾内压也会升高。在工作通道内使用 2.4F 篮筐时，配置 1 和 2 的流量分别提高了 250%和 700%，并且可以在不增加肾内压的情况下使用 2m 静水柱。
当柔性输尿管镜的工作通道被占用时，增加输尿管鞘管直径并不能提高流量。我们提出的将输尿管导管置于或置于鞘管旁的配置可提供迄今为止最高的流量，而不会增加肾内压。
