逆行输尿管镜碎石术中肾盂内压变化的体外研究

In vitro study of intrapelvic pressures using retrograde ureteroscope lithotripsy

摘要:

目的：研究逆行输尿管镜术中不同输尿管硬镜和软镜对肾盂内压的影响。方法：采用离体猪泌尿系统进行模拟手术。使用Wolf F6/7.5输尿管硬镜、Wolf F8/9.8输尿管硬镜、Polyscope输尿管软镜和奥林巴斯P6输尿管软镜中置入200 μm的钬激光光纤。输尿管硬镜放置在输尿管下段、中段和输尿管肾盂交界处，输尿管软镜放置在输尿管肾盂交界处，在灌注压为分别为50、100、200、300、400、500 cmH2O情况下，测量肾盂内压变化。结果：肾盂内压与灌注压之间成线性相关。输尿管硬镜位于输尿管下段时肾盂内压力上升较慢，位于输尿管肾盂交界处时肾盂内压力上升最快。同一灌注压力下，Wolf F6/7.5输尿管镜肾盂内压力小于Wolf F8/9.8输尿管镜。同样置于输尿管肾盂交界处时，使用输尿管硬镜时肾盂内压力明显高于输尿管软镜。根据直线回归方程预测肾盂内压≤ 40 cmH2O时灌注压力大小，可知输尿管硬镜位于输尿管中上段时较小的灌注压力（34.950~44.284 cmH2O）即可使肾盂内压达到临界压力，输尿管硬镜位于输尿管下段时安全灌注压力较大（205.345~313.659 cmH2O）。输尿管软镜可以承受最大的灌注压力而使肾盂内压保持在安全压力范围内，奥林巴斯P6输尿管软镜的安全灌注压（400.457 cmH2O）高于Polyscope组合输尿管软镜（238.419 cmH2O）。结论：为了保障肾盂内低压，处理输尿管中下段结石推荐使用更细的输尿管硬镜处理，处理输尿上段结石时，推荐使用输尿管软镜。

Abstract:

Objective：To evaluate intrapelvic pressures during laser lithotripsy using different semi-rigid and flexible ureteroscopes. Methods：Intrapelvic pressures was measured on a porcine cadaveric urinary system model with two size of semi-rigid ureteroscopes （Wolf F6/7.5 and Wolf F8/9.8） and two models of flexible ureteroscopes（Polyscope and Olympus URF-P6）. 200 μm Holmium laser fiber was placed into the working cannel previously. The semi-rigid ureteroscopes were placed in distal ureter，middle ureter and ureteropelvic junction and the flexible ureteroscopes were fixed in ureteropelvic junction. Intropelvic pressure was recorded at irriga－tion pressures of 50，100，200，300，400，500 cmH2O. Results：There is a linear correlation between intrapelvic pressures and irrigation pressures. The intrapelvic pressures raised slowly when the semi-rigid ureteroscopes were put at distal ureter. The intrapelvic pres－sures raised at the fastest pace when the semi-rigid ureteroscopes were placed at ureteropelvic junction. The intrapelvic pressures using Wolf F6/7.5 ureteroscope were lower than that using Wolf F8/9.8 ureteroscope at the same irrigation pressure. The intrapelvic pres－sures of semi-rigid were higher than those of the flexible ones when ureteroscopes were placed at ureteropelvic junction. According to the equation of linear regression，the value of irrigation pressures was estimated when the intrapelvic pressure reaching 40 cmH2O，and it is found that a low irrigation pressure（34.950 to 44.284 cmH2O） could rise the intrapelvic pressures to 40 cmH2O when the se－mi-rigid ureteroscopes being put at the middle and upper ureter. The safe irrigation pressure was higher（205.345 to 313.659 cmH2O） when the semi-rigid ureteroscopes being placed at the distal ureter. The flexible ureteroscopes could withstand the maximum irrigation pressure keeping the intrapelvic pressures within the safe range，and the safe irrigation pressure of Olympus URF-P6（400.457 cmH2O） was higher than Polyscope（238.419 cmH2O）. Conclusion：In order to maintain the intrapelvic pressures at a low level，thin－ner semi-rigid ureteroscope should be used in the treatment of middle and distal ureteral calculi，and flexible rather than semi-rigid ureteroscope should be used to handle proximal ureteral calculi.