Hemostasis and Safety Analysis of Norepinephrine Irrigation Fluid in Su-FURS Combined With NPUAS Lithotripsy. (Su-FURS: Single-use Flexible Ureteroscope, NPUAS: Negative Pressure Ureteral Access Sheath)
Urinary stone disease is globally prevalent with rising incidence and recurrence, imposing heavy socioeconomic burdens. Flexible ureteroscopy has advanced stone treatment. Single-use flexible ureteroscopes (su-fURS) combined with negative pressure ureteral access sheath (NPUAS), recommended by urology guidelines, improve surgical safety and stone-free rates and can treat stones ≤3 cm. However, su-fURS has poorer image quality, bleeding during lithotripsy may blur vision, frequently impairing efficiency and safety. Norepinephrine (NE), a tyrosine-derived sympathomimetic amine, mainly activates α1 and β1 receptors. Doses above 3 μg/min trigger predominant α1-mediated vasoconstriction of arteries and veins. It can act on mucosal surfaces via irrigation fluid, making it favorable for initial hemostasis of injured mucosa. Firstly, this study aims to evaluate the efficacy and safety of low-concentration norepinephrine (NE) irrigation solution for hemostasis during lithotripsy performed with single-use flexible ureteroscope (su-fURS) combined with NPUAS, fifteen subjects will be enrolled in the study. Secondly, we explore the dose-effect relationships of four concentrations: 2 mg/3 L, 4 mg/3 L, 6 mg/3 L and 8 mg/3 L, and determine the optimal concentration by comprehensively evaluating hemostatic efficacy and safety. A total of 40 subjects will be enrolled, with 10 subjects in each concentration.
• Age 18-75 years of either sex.
• Clinically and radiologically confirmed renal or upper-ureteral stone with operative indication for super flexible ureteroscopic lithotripsy combined with negative pressure ultrasound lithotripsy (su-fURS + NPUAS).
• Subjects with definite surgical indication for upper urinary tract stones, tolerate general anesthesia, and agree to receive the targeted operative procedure.