A new postoperative predictor of time to urinary continence after laparoscopic radical prostatectomy: the urine loss ratio

Abstract

Objectives: To assess the correlation of a newly defined parameter, "urine loss ratio" (ULR), with the time to continence and probability for incontinence after laparoscopic radical prostatectomy (LRP).

Materials and methods: A standardized "micturition protocol" that uses 24-h pad testing to objectively quantify urine loss after removal of the catheter was obtained from 939 patients who underwent LRP and were provided complete follow-up regarding continence. ULR was defined as the weight of urine loss in the pad divided by daily micturition volume, distinguishing between ULR on the first day after catheter removal and the last day of hospital stay. The time to continence was classified as early (0-3 mo), midterm (4-12 mo), and late continence (13-24 mo).

Results: Early continence was attained in 69.8% (n=655) of patients, midterm continence in 18.4% (n=173), and late continence in 3.5% (n=33). Of 939 patients in whom first-day ULR was quantified, 495 patients were not discharged immediately and their last-day ULR was quantified (2.3 d following catheter removal). There was a linear correlation between time to continence and ULR, which was more significant for last- than first-day ULR (p<0.001). A cutoff point of more than 15% of urine loss indicates a high risk of incontinence (ie, 8-fold for first-day ULR, 55-fold for last-day ULR).

Conclusion: ULR predicts the time to continence and may be used to select patients for specific rehabilitation programs and early adjuvant medical therapy, particularly when urine loss exceeds 15%.