A Practical Guide for Intra-Renal Temperature and Pressure Management during Rirs: What Is the Evidence Telling Us

Abstract

Introduction: One of the main limitations of Ho:YAG lithotripsy is represented by its advancement speed. The need for faster lithotripsy has led to the introduction of high-power laser equipment. This general trend in increasing Ho:YAG lithotripsy power has certain points that deserve to be considered and analyzed. The objective is to carry out a narrative review on intrarenal temperature and pressure during ureteroscopy. Methods: A literature search using PUBMED database from inception to December 2021 was performed. The analysis involved a narrative synthesis. Results: Using more power in the laser correlates with an increase in temperature that can be harmful to the kidney. This potential risk can be overcome by increasing either the irrigation inflow or outflow. Increasing irrigant flow can lead to high intrarenal temperature (IRP). The factors that allow the reduction of intrarenal pressure are a low irrigation flow, the use of a ureteral access sheath of adequate diameter according to the equipment used, and the occupation of the working channel by the laser or basket. Conclusion: To maintain a safe temperature profile, it has been proposed to use chilled irrigation fluid, intermittent laser activation or to increase irrigation flow. This last recommendation can lead to increased IRP, which can be overcome by using a UAS. Another option is to use low power laser configurations in order to avoid temperature increases and not require high irrigation flows.

Technique, Feasibility, Utility, Limitations, and Future Perspectives of a New Technique of Applying Direct In-Scope Suction to Improve Outcomes of Retrograde Intrarenal Surgery for Stones

“…(f) Whilst we could not measure temperature and intrarenal pressure whilst using DISS, other reports have conclusively proven that adding suction potentiates this effect in RIRS, mitigating potential complications related to uncontrolled temperatures and pressures in the pelvicalyceal system, especially when using newer powerful lasers [ 16 , 17 , 19 ]. None of our patients in either cohort had pelvicalyceal injuries, life-threatening sepsis, or readmission for infectious-related complications.…”

“…Pop-dusting or pure dusting technique was used as needed in both groups [ 18 ]. We deployed continuous irrigation throughout, ensuring that the pelvicalyceal system was adequately drained by saline and to ensure intrarenal temperature was properly maintained, without compromising any principles of RIRS surgery [ 19 ]. The 3-way adapter for suction was sequentially opened either when a snow-globe effect was noted to aspirate the fragments or intermittently after lithotripsy to aspirate the dust [ 10 ].…”

Outcome of combining 7.5Fr disposable electronic flexible ureteroscope with 10Fr ureteral access sheath in the treatment of renal stones < 2cm: initial experience

“…It is possible to meet standards of clinical lithotripsy when the perfusion pressure is 500 H 2 Ocm, the IPP is only 25.9 H 2 Ocm, and the perfusion ow is 64.4 ml/min. [13]. The success rate of the UAS insertion increased by reducing its diameter, while simultaneously lessening the pressure the sheath exerted on the ureter, which reduced the risk of ischemia injury [2,14].…”

Retrograde intra renal surgery and safety: pressure and temperature. A systematic review

“…As a consequence of mistargeting the stone with the activated laser, the emitted pulses are delivered in a mixture of urine, saline solution, water or iodinated contrast agent, with specific induced vapor bubbles characteristics [32]. This could lead to direct (mucosae laser injuries) and indirect (thermal) damages [33 ▪ ].…”