%0 Journal Article
%T Temperature profiles of calyceal irrigation fluids during flexible ureteroscopic Ho:YAG laser lithotripsy.
%A Teng J
%A Wang Y
%A Jia Z
%A Guan Y
%A Fei W
%A Ai X
%J Int Urol Nephrol
%V 53
%N 3
%D Mar 2021
%M 32989671
%F 2.266
%R 10.1007/s11255-020-02665-x
%X OBJECTIVE: To evaluate calyceal irrigation fluid temperature changes during flexible ureteroscopic Ho:YAG laser lithotripsy.
METHODS: Between May 2019 and January 2020, patients with kidney stones undergoing flexible ureteroscopic Ho:YAG laser lithotripsy were enrolled. A K-type thermocouple was applied for intraoperative temperature measurement. Laser was activated at different power (1 J/20 Hz and 0.5 J/20 Hz) and irrigation (0 ml/min, 15 ml/min and 30 ml/min) settings, temperature-time curve was drawn and time needed to reach 43 °C without irrigation was documented.
RESULTS: Thirty-two patients were enrolled in our study. The temperature-time curve revealed a quick temperature increase followed by a plateau. With 15 ml/min or 30 ml/min irrigation, 43 °C was not reached after 60 s laser activation at both 1 J/20 Hz and 0.5 J/20 Hz. At the power setting of 1 J/20 Hz and irrigation flow rate of 15 ml/min, the temperature rise was significantly higher than other groups. Without irrigation, the time needed to reach 43 °C at 1 J/20 Hz was significantly shorter than that at 0.5 J/20 Hz (8.84 ± 1.41 s vs. 13.71 ± 1.53 s).
CONCLUSIONS: Ho:YAG laser lithotripsy can induce significant temperature rise in calyceal fluid. With sufficient irrigation, temperatures can be limited so that a toxic thermal dose is not reached, when irrigation is closed, the temperature increased sharply and reached 43 °C in a few seconds.