Measurement of renal pelvic pressure during minimally invasive percutaneous nephrolithotomy

Abstract

Objective To introduce a new method to measure renal pelvic pressure in vivo during minimally invasive percutaneous nephrolithotomy （MPCNL）, and investigate its clinical significance. Methods Renal pelvic pressure was measured by baroceptor which was connected to Mindray PM9000 monitor IBP channel and nreteric catheter positioned in renal pelvis during MPCNL, and a computer collected the renal pelvic pressure data each second. Results Renal pelvic pressure was measured in 112 cases during MPCNL, and the influence factors of renal pelvic pressure and its correlation with postoperative fever were analyzed. Conclusion Renal pelvic pressure generally remained lower than a level to back-flow [30 mm Hg （1 mm Hg =0. 133 kPa）] during MPCNL. Any factors which brought about a bad drainage would result in a temporal elevated intrapelvic pressure greater than 30 mm Hg. It＇ s necessary for the surgeons to adjust their manipulation to keep a low renal pelvic pressure. A spurt high renal pelvic pressure greater than 30 mmHg wouldn＇t cause a postoperative fever, while a status of renal pelvic pressure greater than 30 mmHg （longer than 50 s） or a mean renal pelvic pressure greater than 20 mmHg all through the procedure may lead to an enough back-flow, resulting in a postoperative fever. Key words: Percutaneous nephrolithotomy; Renal pelvic pressure; Postoperative fever