Safty Evaluation Of Renal Pelvic Pressure Monitoring During Retrograde Intrarenal Surgery With Syringe Irrigation

Objective To monitor intraluminal renal pelvic pressure during retrograde intrarenal surgery(RIRS) with syringe irrigation. To investigate the safty and feasibility of this irrigation method.Methods Seven patients with kidney calculi and indewlling nephrostomy tube admitted for the flexible ureteroscopic lithotripsy were enrolled from March 2014 to May 2015 in the Second Affiliated Hospital of Zhengzhou University. Two males and five femals, with the age from 29 to 58 years. The pressure was monitored through the nephrostomy tube. The basic flow:all equipments and devices were strictly sterilized at first. Then the measuring pressure apparatus was connected with the nephrostomy tube, making the renal pelvic in a status as similar as the normal RIRS. The pressure channel was comfirmed to be unobstructed.The measuring pressure apparatus was fixed onto the horizontal plane of renal pelvis after a zero adjustment. The lithotripsy was performed until only very small stones fragements(<2mm) were remained.The renal pelvic pressure was real-time monitored during RIRS. All cases were operated by the same surgeon and assistant who pushed water. The patient's temperature, routine blood examination and renal function were measured after RIRS, evaluating the patient's postoperative condition. Ureter, and bladder X-ray (KUB) was performed on postoperative day 1 in all cases, in order to assess the residual stone fragments and position of the double-J stent.Results Seven cases' pelvic pressure monitoring completed 7 times successfully. The mean intra-pelvic pressure(IPP) was 54.8,13.4,22.1,21.8,5.1,17.2, 25.1(cmH2O) (1cmH20=0.098kPa), respectively; The maximum intra-pelvic pressure (IPPmax) was 158,85,88,42,12,46,115(cmH2O), respectively; But the duration of IPPmax was short, lasting about l-3s. The intra-pelvic pressure's (>40cmH2O) duration was 31.12,0.56,2.33,0.00,0.00,0.10,2.31(min), respectively.The time of lithotripsy was 54.73,23.12,28.55,14.45,8.25,9.93, 30.08(min), respectively (median time,23.12min); The water consumption was 2300, 640,950,450,250,270, 1000(ml), respectively(median water consumption 640ml); The mean irrigation rate was 42.02,27.68,33.27,31.14,30.30,27.19, 33.24(ml/min), respectively(median irrigation rate,31.14ml/min). The real-time pressure-time graphs were drawn during RIRS. All patients didn't had a postoperative fever and renal function decline.The white cell count were all nomal. No significant residual stones were retained, and the position of double J tube was good through rechecking the KUB on postoperative day 1.Conclusions The syringe irrigation mothod can control intraluminal renal pelvic pressure less than 40cmH2O during retrograde intrarenal surgery(RIRS). The syringe irrigation method is a feasible, safe and effective irrigation mothod.