Comparison of automated irrigation systems using an in vitro ureteroscopy model

Abstract

Introduction: Two automated irrigation systems have been released for use during endoscopic procedures such as ureteroscopy: the Cogentix RocaFlow® (CRF) and Thermedx FluidSmart® (TFS). Accurate pressure control using automated systems may help providers maintain irrigation pressures within a safe range while also providing clear visualization. Our objective was to directly compare these systems based on their pressure accuracy, pressure-fl ow relationships, and fl uid heating capabilities in order to help providers better utilize the temperature and pressure settings of each system. Materials and Methods: An in vitro ureteroscopy model was used for testing, consisting of a short semirigid ureteroscope (6/7, 5F, 31cm Wolf 425612) connected to a continuous digital pressure transducer (Meriam m1550). Each system pressure output and fl ow-rate, via 100mL beaker fi lling time, was measured using multiple trials at pressure settings between 30 and 300mmHg. Output fl uid temperature was monitored using a digital thermometer (Omega DP25-TH). Results: The pressure output of both systems exceeded the desired setting across the entire tested range, a difference of 15.7±2.4mmHg for the TFS compared to 5.2±1.5mmHg for the CRF (p <0.0001). Related to this fi nding, the TFS also had slightly higher fl ow rates across all trials (7±2mL/min). Temperature testing revealed a similar maximum temperature of 34.0⁰C with both systems, however, the TFS peaked after only 8 minutes and started to plateau as early as 4-5 minutes into the test, while the CRF took over 18 minutes to reach a similar peak. Conclusions: Our in vitro ureteroscopy testing found that the CRF system had better pressure accuracy than the TFS system but with noticeably slower fl uid heating capabilities. Each system provided steady irrigation at safe pressures within their expected operating parameters with small differences in performance that should not limit their ability to provide steady irrigation at safe pressures.

Under pressure: irrigation practice patterns during flexible ureteroscopy

“…11 While there are no data on the most commonly chosen irrigation pressures in North America, a recent bench study of automated irrigation systems conducted by urologists in the United States were done at pressure settings with a maximum of 300 mmHg to mimic clinical practice. 12 In another US bench study where a setting of 200 mmHg with the pressurized saline bag was used, it was noted that a pressure in excess of 300 mmHg may occur in the operating room. 13 We found that North American practice was different to that in Europe where most surgeons used pressurized saline and practiced more uniformly; it was the only region to have more than half of all respondents prefer one irrigation method.…”

Ergonomics and Surgeon Comfort During Flexible Ureteroscopy

“… 26–28 Alternatively, automated irrigation systems have been shown to provide steady irrigation at safe pressures with better visibility 29–31 There are different types of automatic irrigation pumps include Uromat Pump, Thermedx FluidSmart (TFS) ® and the Cogentix RocaFlow (CRF) ® . 30 …”