Novel Dual-Action Pump Shows Promise to Reduce Intra-Renal Pressure and Improve Irrigant Flow in Flexible Ureteroscopy

Abstract

Background/Objective: To describe a novel dual-action pump (DAP) which is hypothesised to reduce mean intrarenal pressure (IRP) and increase irrigation flow during flexible ureterorenoscopy (fURS). The DAP incorporates a low-volume, user-controlled pumping/suctioning unit, to precisely control fluid boluses into the upper urinary tract via a ureterorenoscope and simultaneously draws out an identical volume of the delivered irrigant via a syphoning UAS. This human cadaveric study aims to assess the DAP’s impact on IRP and the irrigant flow rate compared to a traditional UAS. Methods: Twelve fresh frozen human cadaver renal units were studied in situ. An 11/13 UAS was placed under fluoroscopic guidance and a fURS was introduced. Continuous pressure was monitored. The DAP and syphoning UAS were compared to a conventional irrigation system in terms of IRP and irrigant flow at variable irrigant fluid heights and during fluid bolus administration. Results: The mean IRP was reduced by 79–141%. Maximum IRP was reduced by up to 180%. The mean irrigation flow rate was improved by 44–86%. The small sample size of 12 limits the results obtained. Conclusions: The novel DAP system shows promise in reducing intra-renal pressure and improving irrigant flow in flexible ureteroscopy.