Impact of food intake on urodynamic features of orthotopic urinary reservoirs.

Abstract

The inconsistency of urodynamic characteristics among patients with similar, well detubularized urinary reservoirs together with the persistence of nocturnal incontinence in almost a third of such patients has motivated many groups to study in depth the inherent physiological characters of the intestinal segments used. One of the most critical criteria is the effect of food intake on such isolated segments. We determined the effect of food intake on the urodynamic behavior of urinary intestinal reservoirs. A total of 50 male patients with well detubularized orthotopic reservoirs (hemiKock or W neobladders) after radical cystectomy underwent medium fill enterocystometry while fasting for 8 hours. Patients were then given a standardized caloric diet and the test was repeated 2 hours after food intake. Comparisons were made in the whole group of patients and subsets according to continence status, reservoir configuration and reservoir duration. The only significant and consistent finding was the decrease in maximum enterocystometric capacity. This decrease was statistically significant when calculated for the fasting and postprandial states in the whole group (mean +/- SD 539.1 +/- 155.7 and 495.9 +/- 146.2 ml), in continent patients (538 +/- 177 and 505 +/- 168.5 ml) and in patients with enuresis (539 +/- 177 and 481 +/- 106.8 ml, respectively). While the frequency and amplitude of phasic contractions were notably increased postprandially, baseline pressure at mid and maximum capacity were observed to be lowered. However, neither effect achieved statistical significance. Definite urodynamic changes occur in intestinal urinary reservoirs in response to food intake, denoting that these detubularized intestinal segments retain at least in part their native behavior in response to eating. The consistent decrease in maximum capacity together with increased phasic motor activity in a subset of these patients may explain their incontinence episodes. Changing food composition and habits may improve the continence state in this subset of patients.