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Updated: Jan 29, 2026

Retzius-Sparing Robot-Assisted Radical Prostatectomy
Published on: May 19, 2022
Improved Outcomes Utilizing a Valveless-Trocar System during Robot-assisted Radical Prostatectomy (RARP)
Mohammed Shahait1, Ross Cockrell1, Mona Yezdani1
1Department of Surgery, Division of Urology, University of Pennsylvania, Philadelphia, PA.
Introduction:
To evaluate the effect of valveless trocar system (VTS) on intra-operative parameters, peri-operative outcomes, and 30-day postoperative complications in patients undergoing robotic-assisted laparoscopic prostatectomy.
Methods:
A total of 200 consecutive patients undergoing Robot-assisted radical prostatectomy by a single surgeon were prospectively evaluated using either the valveless trocar (n = 100) or standard trocars (n = 100). Patient demographics, intra-operative parameters, length of stay, presence or absence of postoperative nausea and vomiting, analog pain score at 0-6 hours, 6-12 hours, 12-18 hours, and >24 hours, and 30-day postoperative complications were analyzed.
Results:
There were no significant differences in estimated blood loss, intra-operative urine output, length of stay, or 30-day complication rates between the two groups. While the VTS group had higher Body Mass Index (BMI) (28.45 vs. 27.23; P = 0.049), the operative time was significantly shorter in the VTS group (146 minutes vs. 167 minutes; P < .005). The VTS group experienced fewer episodes of nausea (2% vs. 10%; P = 0.0172). The VTS group had less pain intensity compared to the control in the first 18 hours: 0-6 hours (1.9 vs. 2.5; P = 0.034), 6-12 hours (2.8 vs. 3.6; P = 0.044), and 12-18 hours (2.2 vs. 3.1; P = 0.049), respectively.
Conclusion:
The use of a valveless trocar system during robot-assisted robotic prostatectomy may shorten operative times, and reduce postoperative pain scores and nausea episodes without increasing the 30-day complication rate. Further prospective randomized trials should be performed to validate these findings.
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