[Urodynamic behavior of intestinal neobladder: our experience]

To analyze the urodynamic behavior of the intestinal neobladders in our series.

The study comprised 20 patients with a detubularized intestinal neobladder. The ileal segment was utilized in 15 (13 Melchior, 1 Camey and 1 Padovana), the ileocecal segment in 4 (3 Mainz, 1 Le Bag) and detubularized sigmoid in one patient. A urodynamic study was performed in all patients to determine neobladder capacity, presence of peristaltic waves, filling and voiding pressures, peak and mean urinary flow and postvoid residual urine. The patients were also asked about continence, if a collecting device was required and the overall degree of satisfaction.

Mean neobladder capacity was 508 ml., mean reservoir accommodation was 38 ml/cm H2O and 66.7% presented significant peristaltic contractions. Maximum filling pressure was 27 cm H2O. All patients showed peaks in the flowmetry due to the abdominal pressure, with a mean maximum peak flow of 16.6 ml/sec. Mean postvoid residual urine was 43.6 ml. Eighty percent of the patients were continent during the day, 55% were continent during the night and 25% were completely continent. All patients used abdominal pressure for voiding and generally in the sitting position. The overall degree of satisfaction was moderate to high in all but two patients; one required self catheterization and the other had frequent interruptions during work due to leaks during the day, but refused to use a collecting device.

If renal function is preserved and the criteria for radical oncologic treatment are observed, substitution of the compromised bladder should be attempted with a reservoir as physiological as possible. The ideal continent urinary diversion must meet the following prerequisites: adequate capacity, low pressure inside the reservoir, absence of pressure waves, continence and absence of postvoid residual urine. The mean capacity of the intestinal neobladders in this study, as well as the maximum pressure inside the reservoirs were found to be adequate. However, many patients presented peristaltic contractions with urinary leaks in some cases, and the percentage of patients with residual urine also appears to be high. Most of these patients do not require the use of pads during the day, while almost all of the patients require some type of collecting device at night for incontinence. Nevertheless, the patients in this series were generally satisfied with their neobladder.