De novo detrusor underactivity after laparoscopic radical prostatectomy

Objective: The aim of this study was to investigate bladder function following laparoscopic radical prostatectomy, with a focus on de novo detrusor underactivity. Methods: Records on pre- and postoperative urodynamic studies were retrospectively investigated in 110 patients who underwent laparoscopic radical prostatectomy. Patients exhibiting de novo detrusor underactivity were selected on the basis of an overt strain voiding pattern during the postoperative pressure flow study with detrusor pressure at a maximum flow rate < 10 cm H2O accompanied by an increase in abdominal pressure. In these patients, a follow-up urodynamic study was performed to assess subsequent long-term changes in the bladder function. Results: Of the 110 patients, 10 (9.1%) were observed to exhibit de novo detrusor underactivity during the postoperative urodynamic study. During the voiding phase of the pre- and postoperative pressure flow study in these 10 patients, the mean detrusor pressure at maximum flow rate showed a significant decrease postoperatively from 57.6 to 3.0 cm H2O (P < 0.001), although the mean abdominal pressure at maximum flow rate significantly increased from 23.1 to 102.5 cm H2O (P < 0.001). The follow-up urodynamic study performed on seven patients at 36 months following surgery revealed no significant change in each urodynamic parameter. De novo detrusor underactivity persisted even over the long term following surgery, and no improvement in bladder function was observed. Conclusions: Detrusor contractility may be impaired during radical prostatectomy. Postoperative detrusor underactivity following radical prostatectomy seems to be an irreversible phenomenon persisting even over the long term.