Intravesical prostatic protrusion predicts the outcome of a trial without catheter following acute urine retention.

PURPOSE: We prospectively evaluated a simple, noninvasive method to predict the outcome of a voiding trial following acute urine retention (ARU) based on intravesical prostatic protrusion (IPP) using transabdominal ultrasound.
MATERIALS AND METHODS: Males older than 50 years presenting with an initial episode of ARU were included in the study. Patients with prostatic cancer, urinary tract infection, bilateral hydronephrosis or neurological disease were excluded. The duration of catheterization, residual urine volume, serum prostate specific antigen and prostate volume were recorded. The patient bladder was filled with 200 ml normal saline via a catheter in situ. IPP was measured in the mid sagittal section using transabdominal ultrasound. The degree of protrusion was classified as grades 1--5 mm or less, 2--greater than 5 to 10 mm and 3--greater than 10 mm. Uroflowmetry and post-void residual urine were recorded after catheter removal. The voiding trial was judged to be unsuccessful if the patient failed to reestablish satisfactory micturition, with post-void residual urine greater than 100 ml and maximum urine flow less than 10 ml per second.
RESULTS: A total of 100 patients were included in the study. The failure rate of the voiding trial based on grades 1 to 3 IPP were 36% (13 of 36 cases), 58% (11 of 19) and 67% (30 of 45). This rate was significant (chi-square test for trend 0.007).
CONCLUSIONS: IPP is a useful predictor for evaluating the success of a voiding trial following ARU. Patients with a grade 1 prostate may benefit from a trial without a catheter. However, patients with a grade 3 prostate are less likely to do so and would require a more definitive surgical procedure.