Storage detrusor pressure in bilateral hydroureteronephrosis

To determine the detrusor pressure (P(det)) during the storage phase associated with upper urinary tract (UUT) dilatation.

Twenty-seven patients with bilateral hydroureteronephrosis, neither due to organic obstruction nor vesicoureteral reflux, were included. Water cystometry was done according to the recommendations of the International Continence Society [Abrams P., et al.: Scand J Urol Nephrol 1988(suppl 114):5-19]. P(det) at 25, 50, 75 and 100% of bladder capacity was determined using the tag function of a computerized urodynamic system.

The age of the patients ranged from 16 to 81 years; 3 were females and 6 had renal insufficiency. In these 27 patients, high P(det) >15 cm H2O was sustained throughout the storage phase in only 11% of patients, and at 50 and 75% of bladder capacity in 44 and 88% of patients. About half (13/27) of the patients had a P(det) <40 cm H(2)O at capacity. Patients with renal insufficiency had a mean P(det) higher and more sustained over the storage phase compared to patients with normal renal function. The mean P(det) at all measured bladder volumes was significantly higher than in a control group of patients without hydroureteronephrosis.

A P(det) >15 cm H(2)O but not necessarily 40 cm H2O, sustained for part of the storage phase but not necessarily throughout the whole storage phase, was associated with UUT deterioration. A higher and more sustained P(det) during the storage phase was associated with renal insufficiency.