Variation of renal intrapelvic pressure of three body positions during percutaneous nephrolithotomy

Abstract

Objective To explore the affection of different body positions on intrapelvic pressure during percutaneous nephrolithotomy ( PCNL ).Methods Ninety-one patients who underwent PCNL at our hospital were studied,and these patients were divided into three groups based on their body position ( prone position,n=32; lateral position,n=30; obliqu.e supine position,n=29 ).An open-end 6 F ureteral catheter was inserted into the target ureter.The average irrigation fluid was about 337 ml/min;average irrigation pressure was 176 mm Hg ( 1 mm Hg=0.133 kPa ).Intrapelvic pressures were collected once per second with urodynamic work stations,and the data was analyzed.Results The average intrapelvic pressure of different positions during PCNL,prone position,lateral position,and oblique supine position,were ( 30.53 ± 4.79 ),( 31.76 ± 3.55 ),( 18.33 ± 2.71 ) cm H2O ( 1 cm H2O=0.098kPa ),respectively.Intrapelvic pressure of oblique supine position was significant lower than that of prone position and lateral position ( P ＜ 0.01 ),but there was no difference in intrapelvic pressure between prone position and lateral position ( P ＞ 0.05 ).Conclusions Intrapelvic pressures of different positions during PCNL were lower than the safety level ( 40 cmH2O ).The intrapelvic pressure of oblique supine position for PCNL was lower than that of prone and lateral position,but there were no significant difference in intrapelvic pressure between prone and lateral position. Key words: Percutaneous nephrolithotomy; PCNL; Renal pelvic pressure; Intrarenal pressure