The impact of siphoning effect on renal pelvis pressure during ureteroscopy using an in vitro kidney and ureter model

• Published in: World journal of urology Vol. 42; no. 1; p. 415
• Main Authors: Kim, Hyung Joon, Louters, Marne M., Dau, Julie J., Hall, Timothy L., Ghani, Khurshid R., Roberts, William W.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 16.07.2024; Springer Nature B.V
• Subjects: Catheters; Kidneys; Lasers; Medicine; Medicine & Public Health; Nephrology; Oncology; Pelvis; Sensors; Silicones; Suctioning; Ureter; Urology; Flowrate; Irrigation; Siphoning effect; Renal pelvis pressure; Ureteroscopy
• ISSN: 1433-8726; 0724-4983; 1433-8726
• DOI: 10.1007/s00345-024-05120-z

Purpose To experimentally measure renal pelvis pressure (P RP ) in an ureteroscopic model when applying a simple hydrodynamic principle, the siphoning effect. Methods A 9.5Fr disposable ureteroscope was inserted into a silicone kidney-ureter model with its tip positioned at the renal pelvis. Irrigation was delivered through the ureteroscope at 100 cm above the renal pelvis. A Y-shaped adapter was fitted onto the model’s renal pelvis port, accommodating a pressure sensor and a 4 Fr ureteral access catheter (UAC) through each limb. The drainage flowrate through the UAC tip was measured for 60 s each run. The distal tip of the UAC was placed at various heights below or above the center of the renal pelvis to create a siphoning effect. All trials were performed in triplicate for two lengths of 4Fr UACs: 100 cm and 70 cm (modified from 100 cm). Results P RP was linearly dependent on the height difference from the center of the renal pelvis to the UAC tip for both tested UAC lengths. In our experimental setting, P RP can be reduced by 10 cmH 2 0 simply by lowering the distal tip of a 4 Fr 70 cm UAC positioned alongside the ureteroscope by 19.7 cm. When using a 4 Fr 100 cm UAC, P RP can drop 10 cmH 2 0 by lowering the distal tip of the UAC 23.3 cm below the level of the renal pelvis. Conclusion Implementing the siphoning effect for managing P RP during ureteroscopy could potentially enhance safety and effectiveness.