Dr. Nina Harke presented just such a trial. In previous work, her group and others have demonstrated the safety of suprapubic tubes without urethral catheterization for urinary drainage after robotic-assisted radical prostatectomy with equivalent oncologic and functional outcomes to traditional urethral catheterization. Here she presented new data in which 198 men were randomized to RARP with urinary drainage via one of three methods: Group A received an indwelling urethral catheter which was removed on postoperative day (POD) 5; Group B received a suprapubic tube (SPT) which was removed on postoperative day 5; and Group C received a suprapubic tube which was clamped on POD 2 and then was removed on POD 5, which allowed the patient to initiate micturition on POD 2.
The initial primary outcome was not specified in the abstract or presentation, however it seems that the trial was primarily intended to show an improvement postoperative patient comfort while demonstrating equivalent functional outcomes, however Dr. Harke noted that the research team was surprised to find that continence was significantly improved at the time of catheter removal, 3 months postoperatively, and 12 months postoperatively in Group C relative to the other groups. This was quantified by 12-hour pad weights immediately following catheter removal (30 vs 24 vs 14 ml respectively, p = 0.007) as well as the rate of complete continence (defined as 0 ppd, numbers reproduced in the table below). There was no difference in postoperative discomfort, although the difference in amount of postoperative pain medication required approached significance favoring group C (p=0.07 numerical values not given). Baseline characteristics of the groups were similar, indicating good randomization, and there was no difference in any kind of complications with 0 bladder neck contractures observed. Two patients required uncapping of their SPT for urinary retention on POD 2, but these catheters were still removed as expected on POD 5.
One of the defining features of our current era of robotic prostatectomy is the progressively more extreme changes in technique that surgeons are willing to try to for relatively modest improvements in functional outcomes. The Rocco stitch, autologous retropubic urethral sling, AmnioFix, and the Retzius-sparing approach all spring to mind. The last of these is perhaps the most striking in how it seems to have generated a remarkable level of enthusiasm and despite its marked difficulty to learn and a large randomized trial which recently failed to show benefit1. Thus one might expect the emergence of level I evidence for a technique which requires no learning curve would be immediately practice changing, but when moderator Dr. Alex Gorbonos asked for a show of hands of those in the room who would be adopting the Group C practice pattern, not a single hand in the room was raised.
To be fair, the study has some limitations. As mentioned before, it seems that continence was a secondary endpoint in this trial, and there was apparently no correction for multiple testing, which raises the chances of a type II error, although the fact that the effect was seen relatively consistently by different measurements and at different time points make this less likely. Social continence rates (<=1 pads per day) were 100%, suggesting a high level of surgical skill in a favorable patient population, which may limit generalizability to other contexts. The fact that German patients are routinely required to remain hospitalized for 5 days postoperatively may also limit generalizability. Next, while blinding is understandably largely impossible in the immediate postoperative period, the extent to which outcome evaluators at the 3 month and 12 month periods were blinded to treatment allocation is unclear. Finally, Dr. Harke declined to speculate regarding the mechanism by which this improvement in continence might arise.
That said, one wonders whether the biggest barrier to adoption of this technique will be true concerns regarding the data or instead the degree to which this technique defies surgical dogma demanding a stented and drained anastomosis. (Although my own experience in managing bladder spasms after RARP has often lead me to wonder to what extent an indwelling urethral catheter actually achieves either one of those goals.) For those who are able to get past this intuitive hurdle, the next question is obvious. How long will it be before we see the first trial of RARP with foley removal on POD 1, or even a totally tubeless RARP?
Presented by: Nina Harke, MD, St. Antonius Hospital, Gronau, Germany
Written by: Marshall Strother, MD, Chief Resident, Division of Urology, University of Pennsylvania, Philadelphia PA at American Urological Association's 2019 Annual Meeting (AUA 2019), May 3 – 6, 2019 in Chicago, Illinois
References:
1. Menon M, Dalela D, Jamil M, et al. Functional Recovery, Oncologic Outcomes and Postoperative Complications after Robot-Assisted Radical Prostatectomy: An Evidence-Based Analysis Comparing the Retzius Sparing and Standard Approaches. J Urol. 2018;199(5):1210-1217.
2. Nguyen HG, Punnen S, Cowan JE, et al. A Randomized Study of Intraoperative Autologous Retropubic Urethral Sling on Urinary Control after Robotic Assisted Radical Prostatectomy. J Urol. 2017;197(2):369-375.