EAU 2007 ABST[71] - Renal pelvic pressure in patients with stone disease in the course of treatment

Mudraya, I., Khodyreva, L.

Introduction & Objectives:

Renal pelvic pressure (RPP) is the complex urodynamic parameter concerning the both structural (anatomic, hystologic) and functional (smooth muscle tone and contractility) upper urinary tract (UUT) characteristics. As soon as high elevations of the RPP may be harmful for renal function they should be known for in time prevention.

The purpose was to study RPP in patients with stone obstruction in the course of treatment in order to elucidate the factors contributing high pressure elevations.

Material & Methods:

RPP was measured electromanometrically in 41 patients who had transcutaneous nephrostomy indwelling catheter with the UUT stone obstruction and after lythotripsy. Of them 14 patients were investigated during procedure of stone removal by ESWL («Dornier», Germany, “Lit-Urat” and “Medolit”, Russia) or contact lithotripsy; 15 patients with residual stone fragments and steinstrasse were examined in the course of their conservative treatment and between the repeated lithotripsy procedures; and 12 patients were stone-free.

Results:

Basal RPP (19.5+1.5 cm H2O) increased during ESWL procedure by 31+10% in 10 minutes, 66+7% - in 20 minutes and by 87+5% at the end of treatment. RPP monitoring during lithotrypsy didn’t reveal its significant reactions to the change of the lithotriptor’s model, or its mode of operation. However pronounced pressure increments (maximal 61 cm H2O) were found in patients receiving massive fluid infusion (range 200-600 ml). Peristaltic pressure fluctuations disappeared in long-time course ESWL (range 12-40 minutes), and the basal pressure tended to approach the peristaltic component. During contact lithotripsy the highest RPP peaks (maximal 61 cm H2O) were short and more pronounced at the time of urinary tract instrumentation (instrument indwelling and stone fragments mechanical removal) than after the fluid irrigation (range 150-400 ml). In patients receiving spasmolitics or α-adrenoblockers these pressure elevations were less drastic. It should be noted that RPP kept being increased in 80% patients at the time between the repeated lithotripsy procedures (range 14-22 cm H2O mean 17.0+0.8 cm H2O) as well as in 58% stone-free patients (range 13.5-23 cm H2O, mean 14.3+1.1 cm H2O). We suggest the patients with high RPP should be investigated in more grater detail for reason underlay.

Conclusions:

Obtained data reveal the RPP elevations during lithotripsy that depend on the fluid volume infusing, time of the procedure and urinary tract instrumentation. Moreover, RPP in stone-free patients might keep high despite functioning nephrostomy indwelling catheter after lithotripsy. Hence it should be controlled in the course of treatment and stone removal in order to diminish its elevations and harmful renal effects to avoid remote complications.