To compare the variation in pneumoperitoneum and physiologic effects of patients undergoing laparoscopic renal surgery using the valveless trocar insufflation system (VI) vs a conventional insufflation system (CI).

We conducted a single-center, randomized controlled trial in patients undergoing renal surgery at 15 mm Hg insufflation using a VI system vs a CI system. The primary outcome measured was variation in insufflation pressure, and end-tidal CO₂ at 10 and 25 minutes.

Fifty-six patients (VI n = 28 or CI n = 28) met inclusion criteria and were randomized. There was significantly less variability in pressure readings, as measured by coefficient of variation, during VI compared to CI (7.8% vs 15.6%, P < .001). There was significantly less time spent within the range with pressure readings ≥18 mm Hg (median 0.2% vs 16.5%, P < .001) and ≤12 mm Hg (median 1.7% vs 5.6%, P = .011) during VI compared to CI. Additionally, there was significantly less time spent with pressure readings in the “unacceptable” range of ≥20 mm Hg (median 0% vs 0.08%, P < .001) and ≤10 mm Hg (median 0.09% vs 2.6%, P < .001) during the cases with VI compared to CI. End-tidal CO₂ was significantly lower at 10 minutes (P = .036) after insufflation in the valveless trocar group compared to the conventional treatment group. There were no other significant differences in physiologic metrics.

Compared with a CI, the VI provides a significantly more stable pneumoperitoneum during laparoscopic renal surgery and lower end-tidal CO₂ at 10 minutes.