Intrarenal temperature measurement associated with holmium laser intracorporeal lithotripsy in an ex vivo model

Abstract

Introduction The aim of this article was to quantify the effect of the use of holmium laser during intracorporeal lithotripsy in an ex vivo model. Material and methods A simulated model for laser nephro-lithotripsy was designed. Two ex vivo porcine kidneys were used. Electronic thermometer electrodes were inserted on the upper calyx. Intracorporeal lithotripsy was simulated with a holmium laser. Intrarenal temperature was recorded both at the beginning and after one minute of laser use with delta temperature (DT) defined as the difference between them. Measurements were made at different irrigation heights (30, 40, and 50 cm H 2 O), frequency (Hz), and laser energy (J) in addition to the presence or absence of the access sheath. Analysis of factors associated with temperature change was performed. Results Thirty-eight observations were recorded. The measurement without the use of access sheath showed an average DT of 4.9, 5.1, and 6.5°C for 5, 10, and 15 Hz, respectively; however, with a sheath, DTs were 0.2, 0.5, and 1.5°C. In terms of energy, mean DTs of 4.3, 6.1, 5.2, and 13.9°C for 0.5, 0.8, 1.0, and 1.5 J were recorded; in contrast, with a sheath, averages of 0.4, 0.5, 0.5, and 3.8°C, respectively were noted. In the adjusted model, energy, frequency, and use of sheath and water height were significant. Conclusions The configuration of the laser significantly modifies the intrarenal temperature and height of the bladder irrigation. The use of an access sheath provides lower intrarenal temperatures regardless of laser configuration and water height.

Comparison of temperature and renal tissue thermal damage by holmium laser with different energy parameters during lithotripsy: in vitro porcine kidney model

“…Although previous researchers have conducted some similar experiments in vitro and in vivo. However, most of the previous experiments on isolated animal organs or equipment were only for the purpose of observing temperature changes, and less attention was paid to actual histopathological damage [5]. In vivo animal experiments, the in uence of blood ow on temperature changes is fully considered, and the monitored temperature is closer to the reality[6], but it is very di cult to make a urinary calculus model in vivo animals, and the accuracy of temperature monitoring is not as good as that in vitro.…”

Turning up the HEAT: Surgical simulation of the Moses 2.0 laser in an anatomic model

“…Their work sought to adapt their previous findings to an in vivo porcine model and found that temperatures capable of tissue damage were easily achieved but can be negated by increasing irrigation flow rate 15 . Other labs have also evaluated irrigation rates and have determined that increased irrigation rates can mitigate temperature increases during active lasing, as too can the use of a UAS [16][17][18] .…”

“…Other studies have been performed utilizing ex vivo and in vivo models with or without UAS that can simulate the complete ureteral length. It is well-recognized that using a UAS can facilitate higher irrigation flow rates and modulate temperature increases easier, in addition to reducing intrarenal pressures during irrigation 17,23 .…”

The heat is on: the impact of excessive temperature increments on complications of laser treatment for ureteral and renal stones

“…In their study, Gallegos et al [ 8 ] reported that using a ureteral access sheath (UAS) provides lower intrarenal temperatures regardless of laser configuration and irrigation solution height. The rise in temperature obtained per minute with an irrigation height of 50 cm H 2 O, an energy of 1 J, and a frequency of 15 Hz was higher when UAS was not utilized (5.8 °C versus 3.8 °C) [ 8 ]. Similarly, Noureldin et al [ 9 ] investigated the effects of irrigation rates and UAS size on intrarenal temperature during flexible ureteroscopy in a live-anesthetized porcine model.…”